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## Publications of Henry Pfister    :chronological  alphabetical  combined listing:

%% Papers Published
@article{fds342383,
Author = {Reeves, G and Pfister, HD},
Title = {The Replica-Symmetric Prediction for Random Linear
Estimation With Gaussian Matrices Is Exact},
Journal = {Ieee Transactions on Information Theory},
Volume = {65},
Number = {4},
Pages = {2252-2283},
Year = {2019},
Month = {April},
url = {http://dx.doi.org/10.1109/TIT.2019.2891664},
Abstract = {© 2019 IEEE. This paper considers the fundamental limit of
random linear estimation for i.i.d. signal distributions and
i.i.d. Gaussian measurement matrices. Its main contribution
is a rigorous characterization of the asymptotic mutual
information (MI) and minimum mean-square error (MMSE) in
this setting. Under mild technical conditions, our results
show that the limiting MI and MMSE are equal to the values
predicted by the replica method from statistical physics.
This resolves a well-known problem that has remained open
Doi = {10.1109/TIT.2019.2891664},
Key = {fds342383}
}

@article{fds342174,
Author = {Schmidt, C and Pfister, HD and Zdeborová, L},
Title = {Minimal sets to destroy the k-core in random
networks.},
Journal = {Physical Review. E},
Volume = {99},
Number = {2-1},
Pages = {022310},
Year = {2019},
Month = {February},
url = {http://dx.doi.org/10.1103/physreve.99.022310},
Abstract = {We study the problem of finding the smallest set of nodes in
a network whose removal results in an empty k-core, where
the k-core is the subnetwork obtained after the iterative
removal of all nodes of degree smaller than k. This problem
is also known in the literature as finding the minimal
contagious set. The main contribution of our work is an
analysis of the performance of the recently introduced
corehd algorithm [Zdeborová, Zhang, and Zhou, Sci. Rep. 6,
37954 (2016)10.1038/srep37954] on random graphs taken from
the configuration model via a set of deterministic
differential equations. Our analyses provide upper bounds on
the size of the minimal contagious set that improve over
previously known bounds. Our second contribution is a
heuristic called the weak-neighbor algorithm that
outperforms all currently known local methods in the regimes
considered.},
Doi = {10.1103/physreve.99.022310},
Key = {fds342174}
}

@article{fds339599,
Author = {Yoo, I and Imani, MF and Sleasman, T and Pfister, HD and Smith,
DR},
Title = {Enhancing Capacity of Spatial Multiplexing Systems Using
Reconfigurable Cavity-Backed Metasurface Antennas in
Clustered MIMO Channels},
Journal = {Ieee Transactions on Communications},
Volume = {67},
Number = {2},
Pages = {1070-1084},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2019},
Month = {February},
url = {http://dx.doi.org/10.1109/TCOMM.2018.2876899},
Abstract = {© 1972-2012 IEEE. We propose a spatial multiplexing system
using reconfigurable cavity-backed metasurface antennas. The
metasurface antennas consist of a printed cavity with
dynamically tunable metamaterial radiators patterned on one
side and fed by multiple radio frequency ports on the other
side (each port representing one communication node),
forming a shared aperture. By individual tuning of the
radiators, the antennas can generate steerable, concurrent
beams that can be adapted to the properties of
multiple-input-multiple-output (MIMO) channels. In this
paper, we present a 2 × 2 MIMO system with simulated
metasurface antennas as transmit and receive antennas
operating at 5.9 GHz. We demonstrate that the flexibility in
beamforming supported by the metasurface antennas can be
used to achieve low spatial correlation and high SNR gain in
clustered MIMO channels, leading to a significant
improvement of the channel capacity. Numerical studies show
2.36-fold, 2.11-fold enhancements of capacity in MIMO
channels with one and two clusters, respectively, compared
with an MIMO system consisting of linear dipoles. The MIMO
system based on the metasurface antennas can be low cost,
low profile, and low power. The metasurface antenna thus has
potential applications in small cell networks requiring high
data rate under bandwidth, energy, and cost
constraints.},
Doi = {10.1109/TCOMM.2018.2876899},
Key = {fds339599}
}

@article{fds342175,
Author = {Sheikh, A and GraellAmat, A and Liva, G and Häger, C and Pfister,
HD},
Title = {On Low-Complexity Decoding of Product Codes for
High-Throughput Fiber-Optic Systems},
Journal = {International Symposium on Turbo Codes and Iterative
Information Processing, Istc},
Volume = {2018-December},
Year = {2019},
Month = {January},
url = {http://dx.doi.org/10.1109/ISTC.2018.8625279},
Abstract = {© 2018 IEEE. We study low-complexity iterative decoding
algorithms for product codes. We revisit two algorithms
recently proposed by the authors based on bounded distance
decoding (BDD) of the component codes that improve the
performance of conventional iterative BDD (iBDD). We then
propose a novel decoding algorithm that is based on
generalized minimum distance decoding of the component
codes. The proposed algorithm closes over 50% of the
performance gap between iBDD and turbo product decoding
(TPD) based on the Chase-Pyndiah algorithm at a bit error
rate of 10-5. Moreover, the algorithm only leads to a
limited increase in complexity with respect to iBDD and has
significantly lower complexity than TPD. The studied
algorithms are particularly interesting for high-throughput
fiberoptic communications.},
Doi = {10.1109/ISTC.2018.8625279},
Key = {fds342175}
}

@article{fds342176,
Author = {Lian, M and Häger, C and Pfister, HD},
Title = {What can machine learning teach us about
communications?},
Journal = {2018 Ieee Information Theory Workshop, Itw
2018},
Year = {2019},
Month = {January},
url = {http://dx.doi.org/10.1109/ITW.2018.8613331},
Abstract = {© 2018 IEEE Information Theory Workshop, ITW 2018. All
rights reserved. Rapid improvements in machine learning over
the past decade are beginning to have far-reaching effects.
For communications, engineers with limited domain expertise
can now use off-the-shelf learning packages to design
high-performance systems based on simulations. Prior to the
current revolution in machine learning, the majority of
communication engineers were quite aware that system
parameters (such as filter coefficients) could be learned
using stochastic gradient descent. It was not at all clear,
however, that more complicated parts of the system
architecture could be learned as well. In this paper, we
discuss the application of machine-learning techniques to
two communications problems and focus on what can be learned
from the resulting systems. We were pleasantly surprised
that the observed gains in one example have a simple
explanation that only became clear in hindsight. In essence,
deep learning discovered a simple and effective strategy
that had not been considered earlier.},
Doi = {10.1109/ITW.2018.8613331},
Key = {fds342176}
}

@article{fds342384,
Author = {Fougstedt, C and Häger, C and Svensson, L and Pfister, HD and Larsson-Edefors, P},
Title = {ASIC Implementation of Time-Domain Digital Backpropagation
with Deep-Learned Chromatic Dispersion Filters},
Journal = {European Conference on Optical Communication,
Ecoc},
Volume = {2018-September},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1109/ECOC.2018.8535430},
Abstract = {© 2018 IEEE. We consider time-domain digital
backpropagation with chromatic dispersion filters jointly
optimized and quantized using machine-learning techniques.
Compared to the baseline implementations, we show improved
BER performance and >40% power dissipation reductions in
28-nm CMOS.},
Doi = {10.1109/ECOC.2018.8535430},
Key = {fds342384}
}

@article{fds342385,
Author = {Häger, C and Pfister, HD},
Title = {Wideband Time-Domain Digital Backpropagation via Subband
Processing and Deep Learning},
Journal = {European Conference on Optical Communication,
Ecoc},
Volume = {2018-September},
Year = {2018},
Month = {November},
url = {http://dx.doi.org/10.1109/ECOC.2018.8535251},
Abstract = {© 2018 IEEE. We propose a low-complexity sub-banded DSP
architecture for digital backpropagation where the walk-off
effect is compensated using simple delay elements. For a
simulated 96-Gbaud signal and 2500 km optical link, our
method achieves a 2.8 dB SNR improvement over linear
equalization.},
Doi = {10.1109/ECOC.2018.8535251},
Key = {fds342385}
}

@article{fds336004,
Author = {Rengaswamy, N and Calderbank, R and Pfister, HD and Kadhe,
S},
Title = {Synthesis of Logical Clifford Operators via Symplectic
Geometry},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2018-June},
Pages = {791-795},
Publisher = {IEEE},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1109/ISIT.2018.8437652},
Abstract = {© 2018 IEEE. Quantum error-correcting codes can be used to
protect qubits involved in quantum computation. This
requires that logical operators acting on protected qubits
be translated to physical operators (circuits) acting on
physical quantum states. We propose a mathematical framework
for synthesizing physical circuits that implement logical
Clifford operators for stabilizer codes. Circuit synthesis
is enabled by representing the desired physical Clifford
operator in \mathbb{C}-{N\times N} as a 2m\times 2m binary
sym-plectic matrix, where N=2-{m}. We show that for an
\!\!\!\![\!\!\![\ {m, m-k}\ ]\!\!\!]\!\!\!\! stabilizer code
every logical Clifford operator has 2-{k(k+1)/2} symplectic
solutions, and we enumerate them efficiently using
symplectic transvections. The desired circuits are then
obtained by writing each of the solutions as a product of
elementary symplectic matrices. For a given operator, our
assembly of all of its physical realizations enables
optimization over them with respect to a suitable metric.
Our method of circuit synthesis can be applied to any
stabilizer code, and this paper provides a proof of concept
synthesis of universal Clifford gates for the well-known
\!\!\!\![\!\!\![\ 6,4,2\ ]\!\!\!]\!\!\!\! code. Programs
implementing our algorithms can be found at
https://github.com/nrenga/symplectic-arxiv18a.},
Doi = {10.1109/ISIT.2018.8437652},
Key = {fds336004}
}

@article{fds337694,
Author = {Hager, C and Pfister, HD},
Title = {Deep Learning of the Nonlinear Schrödinger Equation in
Fiber-Optic Communications},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2018-June},
Pages = {1590-1594},
Publisher = {IEEE},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1109/ISIT.2018.8437734},
Abstract = {© 2018 IEEE. An important problem in fiber-optic
communications is to invert the nonlinear Schrödinger
equation in real time to reverse the deterministic effects
of the channel. Interestingly, the popular split-step
Fourier method (SSFM) leads to a computation graph that is
reminiscent of a deep neural network. This observation
allows one to leverage tools from machine learning to reduce
complexity. In particular, the main disadvantage of the SSFM
is that its complexity using M steps is at least M times
larger than a linear equalizer. This is because the linear
SSFM operator is a dense matrix. In previous work,
truncation methods such as frequency sampling, wavelets, or
least-squares have been used to obtain 'cheaper' operators
that can be implemented using filters. However, a large
number of filter taps are typically required to limit
truncation errors. For example, Ip and Kahn showed that for
a 10 Gbaud signal and 2000 km optical link, a truncated SSFM
with 25 steps would require 70-tap filters in each step and
100 times more operations than linear equalization. We find
that, by jointly optimizing all filters with deep learning,
the complexity can be reduced significantly for similar
accuracy. Using optimized 5-tap and 3-tap filters in an
alternating fashion, one requires only around 2-6 times the
complexity of linear equalization, depending on the
implementation.},
Doi = {10.1109/ISIT.2018.8437734},
Key = {fds337694}
}

@article{fds337695,
Author = {Santi, E and Hager, C and Pfister, HD},
Title = {Decoding Reed-Muller Codes Using Minimum- Weight Parity
Checks},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2018-June},
Pages = {1296-1300},
Publisher = {IEEE},
Year = {2018},
Month = {August},
url = {http://dx.doi.org/10.1109/ISIT.2018.8437637},
Abstract = {© 2018 IEEE. Reed-Muller (RM) codes exhibit good
performance under maximum-likelihood (ML) decoding due to
their highly-symmetric structure. In this paper, we explore
the question of whether the code symmetry of RM codes can
also be exploited to achieve near-ML performance in
practice. The main idea is to apply iterative decoding to a
highly-redundant parity-check (PC) matrix that contains only
the minimum-weight dual codewords as rows. As examples, we
consider the peeling decoder for the binary erasure channel,
linear-programming and belief propagation (BP) decoding for
the binary-input additive white Gaussian noise channel, and
bit-flipping and BP decoding for the binary symmetric
channel. For short block lengths, it is shown that near-ML
performance can indeed be achieved in many cases. We also
propose a method to tailor the PC matrix to the received
observation by selecting only a small fraction of useful
minimum-weight PCs before decoding begins. This allows one
to both improve performance and significantly reduce
complexity compared to using the full set of minimum-weight
PCs.},
Doi = {10.1109/ISIT.2018.8437637},
Key = {fds337695}
}

@article{fds337696,
Author = {Reeves, G and Pfister, HD and Dytso, A},
Title = {Mutual Information as a Function of Matrix SNR for Linear
Gaussian Channels},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2018-June},
Pages = {1754-1758},
Publisher = {IEEE},
Year = {2018},
Month = {August},
ISBN = {9781538647806},
url = {http://dx.doi.org/10.1109/ISIT.2018.8437326},
Abstract = {© 2018 IEEE. This paper focuses on the mutual information
and minimum mean-squared error (MMSE) as a function a
matrix-valued signal-to-noise ratio (SNR) for a linear
Gaussian channel with arbitrary input distribution. As shown
by Lamarca, the mutual-information is a concave function of
a positive semidefinite matrix, which we call the matrix
SNR. This implies that the mapping from the matrix SNR to
the MMSE matrix is decreasing monotone. Building upon these
functional properties, we start to construct a unifying
framework that provides a bridge between classical
information-theoretic inequalities, such as the entropy
power inequality, and interpolation techniques used in
statistical physics and random matrix theory. This framework
provides new insight into the structure of phase transitions
in coding theory and compressed sensing. In particular, it
is shown that the parallel combination of linear channels
with freely-independent matrices can be characterized
succinctly via free convolution.},
Doi = {10.1109/ISIT.2018.8437326},
Key = {fds337696}
}

@article{fds336001,
Author = {Hager, C and Pfister, HD},
Title = {Approaching Miscorrection-Free Performance of Product Codes
with Anchor Decoding},
Journal = {Ieee Transactions on Communications},
Volume = {66},
Number = {7},
Pages = {2797-2808},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2018},
Month = {July},
url = {http://dx.doi.org/10.1109/TCOMM.2018.2816073},
Abstract = {© 1972-2012 IEEE. Product codes (PCs) protect a 2-D array
of bits using short component codes. Assuming transmission
over the binary symmetric channel, the decoding is commonly
performed by iteratively applying bounded-distance decoding
to the component codes. For this coding scheme, undetected
errors in the component decoding - also known as
miscorrections - significantly degrade the performance. In
this paper, we propose a novel iterative decoding algorithm
for PCs which can detect and avoid most miscorrections. The
algorithm can also be used to decode many recently proposed
classes of generalized PCs, such as staircase, braided, and
half-product codes. Depending on the component code
parameters, our algorithm significantly outperforms the
conventional iterative decoding method. As an example, for
double-error-correcting Bose-Chaudhuri-Hocquenghem component
codes, the net coding gain can be increased by up to 0.4 dB.
Moreover, the error floor can be lowered by orders of
magnitude, up to the point where the decoder performs
virtually identical to a genie-aided decoder that avoids all
miscorrections. We also discuss post-processing techniques
that can be used to reduce the error floor even
further.},
Doi = {10.1109/TCOMM.2018.2816073},
Key = {fds336001}
}

@article{fds336002,
Author = {Hager, C and Pfister, HD},
Title = {Nonlinear interference mitigation via deep neural
networks},
Journal = {2018 Optical Fiber Communications Conference and Exposition,
Ofc 2018 Proceedings},
Pages = {1-3},
Year = {2018},
Month = {June},
ISBN = {9781943580385},
Abstract = {© 2018 OSA. A neural-network-based approach is presented to
efficiently implement digital backpropagation (DBP). For a
32×100 km fiber-optic link, the resulting 'learned' DBP
significantly reduces the complexity compared to
conventional DBP implementations.},
Key = {fds336002}
}

@article{fds336003,
Author = {Häger, C and Pfister, HD},
Title = {Nonlinear interference mitigation via deep neural
networks},
Journal = {Optics Infobase Conference Papers},
Volume = {Part F84-OFC 2018},
Publisher = {OSA},
Year = {2018},
Month = {January},
url = {http://dx.doi.org/10.1364/OFC.2018.W3A.4},
Abstract = {© OSA 2018. A neural-network-based approach is presented to
efficiently implement digital backpropagation (DBP). For a
32×100 km fiber-optic link, the resulting “learned“ DBP
significantly reduces the complexity compared to
conventional DBP implementations.},
Doi = {10.1364/OFC.2018.W3A.4},
Key = {fds336003}
}

@article{fds333681,
Author = {Häger, C and Pfister, HD},
Title = {Miscorrection-free Decoding of Staircase
Codes},
Journal = {European Conference on Optical Communication,
Ecoc},
Volume = {2017-September},
Pages = {1-3},
Publisher = {IEEE},
Year = {2017},
Month = {September},
url = {http://dx.doi.org/10.1109/ECOC.2017.8345919},
Abstract = {© 2017 IEEE. We propose a novel decoding algorithm for
staircase codes which reduces the effect of undetected
component code miscorrections. The algorithm significantly
improves performance, while retaining a low-complexity
implementation suitable for high-speed optical transport
networks.},
Doi = {10.1109/ECOC.2017.8345919},
Key = {fds333681}
}

@article{fds328986,
Author = {Charbonneau, P and Li, YC and Pfister, HD and Yaida,
S},
Title = {Cycle-expansion method for the Lyapunov exponent,
susceptibility, and higher moments.},
Journal = {Physical Review. E},
Volume = {96},
Number = {3-1},
Pages = {032129},
Year = {2017},
Month = {September},
url = {http://dx.doi.org/10.1103/physreve.96.032129},
Abstract = {Lyapunov exponents characterize the chaotic nature of
dynamical systems by quantifying the growth rate of
uncertainty associated with the imperfect measurement of
initial conditions. Finite-time estimates of the exponent,
however, experience fluctuations due to both the initial
condition and the stochastic nature of the dynamical path.
The scale of these fluctuations is governed by the Lyapunov
susceptibility, the finiteness of which typically provides a
sufficient condition for the law of large numbers to apply.
Here, we obtain a formally exact expression for this
susceptibility in terms of the Ruelle dynamical ζ function
for one-dimensional systems. We further show that, for
systems governed by sequences of random matrices, the cycle
expansion of the ζ function enables systematic computations
of the Lyapunov susceptibility and of its higher-moment
generalizations. The method is here applied to a class of
dynamical models that maps to static disordered spin chains
with interactions stretching over a varying distance and is
tested against Monte Carlo simulations.},
Doi = {10.1103/physreve.96.032129},
Key = {fds328986}
}

@article{fds327403,
Author = {Jian, YY and Pfister, HD and Narayanan, KR},
Title = {Approaching Capacity at High Rates with Iterative
Hard-Decision Decoding},
Journal = {Ieee Transactions on Information Theory},
Volume = {63},
Number = {9},
Pages = {5752-5773},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2017},
Month = {September},
url = {http://dx.doi.org/10.1109/TIT.2017.2717838},
Abstract = {© 1963-2012 IEEE. A variety of low-density parity-check
(LDPC) ensembles have now been observed to approach capacity
with message-passing decoding. However, all of them use soft
(i.e., non-binary) messages and a posteriori probability
decoding of their component codes. In this paper, we show
that one can approach capacity at high rates using iterative
hard-decision decoding (HDD) of generalized product codes.
Specifically, a class of spatially coupled generalized LDPC
codes with Bose-Chaudhuri-Hocquengham component codes is
considered, and it is observed that, in the high-rate
regime, they can approach capacity under the proposed
iterative HDD. These codes can be seen as generalized
product codes and are closely related to braided block
codes. An iterative HDD algorithm is proposed that enables
one to analyze the performance of these codes via density
evolution.},
Doi = {10.1109/TIT.2017.2717838},
Key = {fds327403}
}

@article{fds326795,
Author = {Kudekar, S and Kumar, S and Mondelli, M and Pfister, HD and Sasoǧlu, E and Urbanke, RL},
Title = {Reed-muller codes achieve capacity on erasure
channels},
Journal = {Ieee Transactions on Information Theory},
Volume = {63},
Number = {7},
Pages = {4298-4316},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2017},
Month = {July},
url = {http://dx.doi.org/10.1109/TIT.2017.2673829},
Abstract = {© 2017 IEEE. We introduce a new approach to proving that a
sequence of deterministic linear codes achieves capacity on
an erasure channel under maximum a posteriori decoding.
Rather than relying on the precise structure of the codes,
our method exploits code symmetry. In particular, the
technique applies to any sequence of linear codes where the
blocklengths are strictly increasing, the code rates
converge, and the permutation group of each code is doubly
transitive. In other words, we show that symmetry alone
implies near-optimal performance. An important consequence
of this result is that a sequence of Reed-Muller codes with
increasing blocklength and converging rate achieves
capacity. This possibility has been suggested previously in
the literature but it has only been proven for cases where
the limiting code rate is 0 or 1. Moreover, these results
extend naturally to all affine-invariant codes and, thus, to
extended primitive narrow-sense BCH codes. This also
resolves, in the affirmative, the existence question for
capacity-achieving sequences of binary cyclic codes. The
primary tools used in the proof are the sharp threshold
property for symmetric monotone Boolean functions and the
area theorem for extrinsic information transfer
functions.},
Doi = {10.1109/TIT.2017.2673829},
Key = {fds326795}
}

@article{fds326794,
Author = {Häger, C and Pfister, HD and GraellAmat, A and Brännström,
F},
Title = {Density evolution for deterministic generalized product
codes on the binary erasure channel at high
rates},
Journal = {Ieee Transactions on Information Theory},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2017},
Month = {July},
url = {http://dx.doi.org/10.1109/TIT.2017.2689783},
Abstract = {© 2017 IEEE. Generalized product codes (GPCs) are
extensions of product codes (PCs), where code symbols are
protected by two component codes but not necessarily
arranged in a rectangular array. We consider a deterministic
construction of GPCs (as opposed to randomized code
ensembles) and analyze the asymptotic performance over the
binary erasure channel under iterative decoding. Our code
construction encompasses several classes of GPCs previously
proposed in the literature, such as irregular PCs, blockwise
braided codes, and staircase codes. It is assumed that the
component codes can correct a fixed number of erasures and
that the length of each component code tends to infinity. We
show that this setup is equivalent to studying the behavior
of a peeling algorithm applied to a sparse inhomogeneous
random graph. Using a convergence result for these graphs,
we derive the density evolution equations that characterize
the asymptotic decoding performance. As an application, we
discuss the design of irregular GPCs, employing a mixture of
component codes with different erasure-correcting
capabilities.},
Doi = {10.1109/TIT.2017.2689783},
Key = {fds326794}
}

@article{fds324463,
Author = {Sabag, O and Permuter, HH and Pfister, HD},
Title = {A Single-Letter Upper Bound on the Feedback Capacity of
Unifilar Finite-State Channels},
Journal = {Ieee Transactions on Information Theory},
Volume = {63},
Number = {3},
Pages = {1392-1409},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2017},
Month = {March},
url = {http://dx.doi.org/10.1109/TIT.2016.2636851},
Abstract = {© 1963-2012 IEEE. An upper bound on the feedback capacity
of unifilar finite-state channels (FSCs) is derived. A new
technique, called the Q-context mapping, is based on a
construction of a directed graph that is used for a
sequential quantization of the receiver's output sequences
to a finite set of contexts. For any choice of Q-graph, the
feedback capacity is bounded by a single-letter expression,
Cfb ≤ sup I (X, S; Y|Q), where the supremum is over p(x|s,
q) and the distribution of (S, Q) is their stationary
distribution. It is shown that the bound is tight for all
unifilar FSCs, where feedback capacity is known: channels
where the state is a function of the outputs, the trapdoor
channel, Ising channels, the no-consecutive-ones
input-constrained erasure channel, and the memoryless
channel. Its efficiency is also demonstrated by deriving a
new capacity result for the dicode erasure channel; the
upper bound is obtained directly from the above-mentioned
expression and its tightness is concluded with a general
sufficient condition on the optimality of the upper bound.
This sufficient condition is based on a fixed point
principle of the BCJR equation and, indeed, formulated as a
simple lower bound on feedback capacity of unifilar FSCs for
arbitrary Q-graphs. This upper bound indicates that a
single-letter expression might exist for the capacity of
finite-state channels with or without feedback based on a
construction of auxiliary random variable with specified
structure, such as the Q-graph, and not with i.i.d
distribution. The upper bound also serves as a non-trivial
bound on the capacity of channels without feedback, a
problem that is still open.},
Doi = {10.1109/TIT.2016.2636851},
Key = {fds324463}
}

@article{fds325508,
Author = {Sabag, O and Permuter, HH and Pfister, HD},
Title = {Single-letter bounds on the feedback capacity of unifilar
finite-state channels},
Journal = {2016 Ieee International Conference on the Science of
Electrical Engineering, Icsee 2016},
Publisher = {IEEE},
Year = {2017},
Month = {January},
ISBN = {9781509021529},
url = {http://dx.doi.org/10.1109/ICSEE.2016.7806200},
Abstract = {© 2016 IEEE. Upper and lower bounds on the feedback
capacity of unifilar finite-state channels (FSCs) are
derived. The upper bound is derived using a new technique,
called the Q-contexts, which is based on a construction of a
directed graph that is used to quantize recursively the
receiver's output sequences to a finite set of contexts. For
any choice of Q-graph, the feedback capacity is bounded by a
single-letter expression, Cfb ≤ sup I (X, S; Y |Q), where
the supremum is over Px|s,q and the distribution of (S, Q)
is their stationary distribution. The bound is tight for all
unifilar FSCs where feedback capacity is known: channels
where the state is a function of the outputs, the trapdoor
channel, Ising channels, the no-consecutive-ones
input-constrained erasure channel and for the memoryless
channel. The upper bound indicates that a single-letter
expression might exist for the capacity of finite-state
channels with or without feedback which are based on a
construction of auxiliary random variable with memory, such
as Q-graph, and not with i.i.d distribution. The lower bound
provides a sufficient condition for the optimality of the
upper bound, however, it is formulated such that independent
lower bounds on feedback capacity may be calculated. The
efficiency of these bounds is demonstrated by deriving a new
capacity result for the dicode erasure channel (DEC). The
upper bound also serves as a non-trivial bound on the
capacity of channels without feedback, a problem that is
still open.},
Doi = {10.1109/ICSEE.2016.7806200},
Key = {fds325508}
}

@article{fds343757,
Author = {Häger, C and Pfister, HD},
Title = {Approaching Miscorrection-free Performance of Product and
Generalized Product Codes.},
Journal = {Corr},
Volume = {abs/1711.07805},
Year = {2017},
Key = {fds343757}
}

@article{fds322709,
Author = {Kumar, S and Calderbank, R and Pfister, HD},
Title = {Beyond double transitivity: Capacity-achieving cyclic codes
on erasure channels},
Journal = {2016 Ieee Information Theory Workshop, Itw
2016},
Pages = {241-245},
Publisher = {IEEE},
Year = {2016},
Month = {October},
ISBN = {9781509010905},
url = {http://dx.doi.org/10.1109/ITW.2016.7606832},
Abstract = {© 2016 IEEE. Recently, sequences of error-correcting codes
with doubly-transitive permutation groups were shown to
achieve capacity on erasure channels under symbol-wise
maximum a posteriori (MAP) decoding. From this, it follows
that Reed-Muller and primitive narrow-sense BCH codes
extend this result to a large family of cyclic codes by
considering codes whose permutation groups satisfy a
condition weaker than double transitivity. The article
combines two simple technical contributions. First, we show
that the transition width of a monotone boolean function is
O(1/log k), where k is the size of the smallest orbit
induced by its symmetry group. The proof is based on
Talagrand's lower bound on influences for monotone boolean
functions. Second, we consider the extrinsic information
transfer (EXIT) function of an Fq-linear cyclic code whose
blocklength N divides qt-1 and is coprime with q-1. We show
that this EXIT function is a monotone boolean function whose
symmetry group contains no orbits of size smaller than the
smallest prime divisor of t. Combining these, we show that
sequences of cyclic codes, whose blocklengths satisfy the
above conditions, achieve capacity on the q-ary erasure
channel if all prime divisors of t tend to
infinity.},
Doi = {10.1109/ITW.2016.7606832},
Key = {fds322709}
}

@article{fds322710,
Author = {Hager, C and Amat, AGI and Pfister, HD and Brannstrom,
F},
Title = {Density evolution for deterministic generalized product
codes with higher-order modulation},
Journal = {International Symposium on Turbo Codes and Iterative
Information Processing, Istc},
Volume = {2016-October},
Pages = {236-240},
Publisher = {IEEE},
Year = {2016},
Month = {October},
ISBN = {9781509034017},
url = {http://dx.doi.org/10.1109/ISTC.2016.7593112},
Abstract = {© 2016 IEEE. Generalized product codes (GPCs) are
extensions of product codes (PCs) where coded bits are
protected by two component codes but not necessarily
arranged in a rectangular array. It has recently been shown
that there exists a large class of deterministic GPCs
(including, e.g., irregular PCs, half-product codes,
staircase codes, and certain braided codes) for which the
asymptotic performance under iterative bounded-distance
decoding over the binary erasure channel (BEC) can be
rigorously characterized in terms of a density evolution
analysis. In this paper, the analysis is extended to the
case where transmission takes place over parallel BECs with
different erasure probabilities. We use this model to
predict the code performance in a coded modulation setup
with higher-order signal constellations. We also discuss the
design of the bit mapper that determines the allocation of
the coded bits to the modulation bits of the signal
constellation.},
Doi = {10.1109/ISTC.2016.7593112},
Key = {fds322710}
}

@article{fds322711,
Author = {Sanatkar, MR and Pfister, HD},
Title = {Increasing the rate of spatially-coupled codes via optimized
irregular termination},
Journal = {International Symposium on Turbo Codes and Iterative
Information Processing, Istc},
Volume = {2016-October},
Pages = {31-35},
Publisher = {IEEE},
Year = {2016},
Month = {October},
ISBN = {9781509034017},
url = {http://dx.doi.org/10.1109/ISTC.2016.7593071},
Abstract = {© 2016 IEEE. In this paper, we consider the rate-loss
problem for spatially-coupled LDPC (SC-LDPC) codes on the
binary erasure channel. Although SC-LDPC codes have good
noise thresholds under belief-propagation (BP) decoding,
they also suffer a rate-loss due to termination that is
significant at moderate blocklengths. Our idea is to attach
additional variable nodes at the boundary using an irregular
degree distribution. Then, this degree distribution is
optimized to improve the code rate without reducing the BP
threshold. The optimization is formulated as an linear
program and solved numerically. Our results show that the
code rate can be increased by a reasonable amount without
decreasing the BP threshold.},
Doi = {10.1109/ISTC.2016.7593071},
Key = {fds322711}
}

@article{fds322712,
Author = {Sabag, O and Permuter, HH and Pfister, HD},
Title = {A single-letter upper bound on the feedback capacity of
unifilar finite-state channels},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {310-314},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541311},
Abstract = {© 2016 IEEE. A single-letter upper bound on the feedback
capacity of a unifilar finite-state channel is derived. The
upper bound is tight for all cases where the feedback
capacity is known. Its efficiency is also demonstrated by
direct application of the bound on the dicode erasure
channel, which results in a new capacity result. The bound
is based on a new technique, called the Q-contexts mapping,
where the channel outputs are recursively quantized to a
finite set, called the contexts set.},
Doi = {10.1109/ISIT.2016.7541311},
Key = {fds322712}
}

@article{fds322713,
Author = {Pfister, HD and Urbanke, R},
Title = {Near-optimal finite-length scaling for polar codes over
large alphabets},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {215-219},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541292},
Abstract = {© 2016 IEEE. For any prime power q, Mori and Tanaka
introduced a family of q-ary polar codes based on q by q
Reed-Solomon polarization kernels. For transmission over a
q-ary erasure channel, they also derived a closed-form
recursion for the erasure probability of each effective
channel. In this paper, we use that expression to analyze
the finite-length scaling of these codes on q-ary erasure
channel with erasure probability ϵ ⋯ (0, 1). Our primary
result is that, for any γ > 0 and δ > 0, there is a q0
such that, for all q ≥ q0, the fraction of effective
channels with erasure rate at most N-γ is at least 1 - ϵ -
O(N-1/2+δ), where N = qn is the blocklength. Since the gap
to the channel capacity 1 - ϵ cannot vanish faster than
O(N-1/2), this establishes near-optimal finite-length
scaling for this family of codes. Our approach can be seen
as an extension of a similar analysis for binary polar codes
by Mondelli, Hassani, and Urbanke.},
Doi = {10.1109/ISIT.2016.7541292},
Key = {fds322713}
}

@article{fds322714,
Author = {Reeves, G and Pfister, HD},
Title = {The replica-symmetric prediction for compressed sensing with
Gaussian matrices is exact},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {665-669},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541382},
Abstract = {© 2016 IEEE. This paper considers the fundamental limit of
compressed sensing for i.i.d. signal distributions and
i.i.d. Gaussian measurement matrices. Its main contribution
is a rigorous characterization of the asymptotic mutual
information (MI) and minimum mean-square error (MMSE) in
this setting. Under mild technical conditions, our results
show that the limiting MI and MMSE are equal to the values
predicted by the replica method from statistical physics.
This resolves a well-known problem that has remained open
Doi = {10.1109/ISIT.2016.7541382},
Key = {fds322714}
}

@article{fds319310,
Author = {Hager, C and Pfister, HD and Graell I Amat and A and Brannstrom,
F},
Title = {Deterministic and ensemble-based spatially-coupled product
codes},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {2114-2118},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541672},
Abstract = {© 2016 IEEE. Several authors have proposed
spatially-coupled (or convolutional-like) variants of
product codes (PCs). In this paper, we focus on a
parametrized family of generalized PCs that recovers some of
these codes (e.g., staircase and block-wise braided codes)
as special cases and study the iterative decoding
performance over the binary erasure channel. Even though our
code construction is deterministic (and not based on a
randomized ensemble), we show that it is still possible to
rigorously derive the density evolution (DE) equations that
govern the asymptotic performance. The obtained DE equations
are then compared to those for a related spatially-coupled
PC ensemble. In particular, we show that there exists a
family of (deterministic) braided codes that follows the
same DE equation as the ensemble, for any spatial length and
coupling width.},
Doi = {10.1109/ISIT.2016.7541672},
Key = {fds319310}
}

@article{fds319311,
Author = {Kumar, S and Calderbank, R and Pfister, HD},
Title = {Reed-muller codes achieve capacity on the quantum erasure
channel},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {1750-1754},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541599},
Abstract = {© 2016 IEEE. The quantum erasure channel is the simplest
example of a quantum communication channel and its
information capacity is known precisely. The subclass of
quantum error-correcting codes called stabilizer codes is
known to contain capacity-achieving sequences for the
quantum erasure channel, but no efficient method is known to
describe a capacity-achieving code sequence for the quantum
erasure channel. In particular, we show that
Calderbank-Shor-Steane (CSS) stabilizer codes constructed
from self-orthogonal binary linear codes are
capacity-achieving on the quantum erasure channel if the
binary linear codes are capacity-achieving on the binary
erasure channel. Recently, Reed-Muller codes were shown to
achieve capacity on classical erasure channels. Using this,
we show that CSS codes constructed from binary Reed-Muller
codes achieve the capacity of the quantum erasure channel.
The capacity-achieving nature of these CSS codes is also
explained from a GF(4) perspective.},
Doi = {10.1109/ISIT.2016.7541599},
Key = {fds319311}
}

@article{fds319312,
Author = {Kudekar, S and Kumar, S and Mondelli, M and Pfister, HD and Urbankez,
R},
Title = {Comparing the bit-MAP and block-MAP decoding thresholds of
reed-muller codes on BMS channels},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2016-August},
Pages = {1755-1759},
Publisher = {IEEE},
Year = {2016},
Month = {August},
ISBN = {9781509018062},
url = {http://dx.doi.org/10.1109/ISIT.2016.7541600},
Abstract = {© 2016 IEEE. The question whether RM codes are
capacity-achieving is a long-standing open problem in coding
theory that was recently answered in the affirmative for
transmission over erasure channels [1], [2]. Remarkably, the
proof does not rely on specific properties of RM codes,
apart from their symmetry. Indeed, the main technical result
consists in showing that any sequence of linear codes, with
doubly-transitive permutation groups, achieves capacity on
the memoryless erasure channel under bit-MAP decoding. Thus,
a natural question is what happens under block-MAP decoding.
In [1], [2], by exploiting further symmetries of the code,
the bit-MAP threshold was shown to be sharp enough so that
the block erasure probability also converges to 0. However,
this technique relies heavily on the fact that the
transmission is over an erasure channel. We present an
alternative approach to strengthen results regarding the
bit-MAP threshold to block-MAP thresholds. This approach is
based on a careful analysis of the weight distribution of RM
codes. In particular, the flavor of the main result is the
following: assume that the bit-MAP error probability decays
as N-δ, for some δ > 0. Then, the block-MAP error
probability also converges to 0. This technique applies to
transmission over any binary memoryless symmetric channel.
Thus, it can be thought of as a first step in extending the
proof that RM codes are capacity-achieving to the general
case.},
Doi = {10.1109/ISIT.2016.7541600},
Key = {fds319312}
}

@article{fds322715,
Author = {Hager, C and Pfister, HD and Amat, AG and Brannstrom,
F},
Title = {Density evolution and error floor analysis for staircase and
braided codes},
Journal = {2016 Optical Fiber Communications Conference and Exhibition,
Ofc 2016},
Year = {2016},
Month = {August},
ISBN = {9781943580071},
Abstract = {© 2016 OSA. We analyze deterministically constructed (i.e.,
non-ensemble-based) codes in the waterfall and error floor
region. The analysis directly applies to several FEC classes
proposed for high-speed OTNs such as staircase and braided
codes.},
Key = {fds322715}
}

@article{fds319313,
Author = {Kudekar, S and Pfister, HD and Kumar, S and Şaşoǧlu, E and Mondelli,
M and Urbanke, R},
Title = {Reed-Muller codes achieve capacity on erasure
channels},
Journal = {Proceedings of the Annual Acm Symposium on Theory of
Computing},
Volume = {19-21-June-2016},
Pages = {658-669},
Publisher = {ACM Press},
Year = {2016},
Month = {June},
ISBN = {9781450341325},
url = {http://dx.doi.org/10.1145/2897518.2897584},
Abstract = {© 2016 ACM. We introduce a new approach to proving that a
sequence of deterministic linear codes achieves capacity on
an erasure channel under maximum a posteriori decoding.
Rather than relying on the precise structure of the codes,
our method exploits code symmetry. In particular, the
technique applies to any sequence of linear codes where the
block lengths are strictly increasing, the code rates
converge, and the permutation group of each code is doubly
transitive. In a nutshell, we show that symmetry alone
implies near-optimal performance. An important consequence
of this result is that a sequence of Reed-Muller codes with
increasing block length and converging rate achieves
capacity. This possibility has been suggested previously in
the literature, but it has only been proven for cases where
the limiting code rate is 0 or 1. Moreover, these results
extend naturally to affine-invariant codes and, thus, to all
extended primitive narrow-sense BCH codes. This is used to
resolve, in the affirmative, the existence question for
capacity-achieving sequences of binary cyclic codes. The
primary tools used in the proofs are the sharp threshold
property for symmetric monotone boolean functions and the
area theorem for extrinsic information transfer (EXIT)
functions.},
Doi = {10.1145/2897518.2897584},
Key = {fds319313}
}

@article{fds322716,
Author = {Kumar, S and Vem, A and Narayanan, K and Pfister,
HD},
Title = {Spatially-coupled codes for write-once memories},
Journal = {2015 53rd Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2015},
Pages = {125-131},
Publisher = {IEEE},
Year = {2016},
Month = {April},
ISBN = {9781509018239},
url = {http://dx.doi.org/10.1109/ALLERTON.2015.7446994},
capacity-achieving coding schemes for write-once memory
(WOM) systems. The construction is based on
spatially-coupled compound LDGM/LDPC codes. Both noiseless
systems and systems with read errors are considered.
Compound LDGM/LDPC codes are known to achieve capacity under
MAP decoding for the closely related Gelfand-Pinsker problem
and their coset decomposition provides an elegant way to
encode the messages while simultaneously providing error
protection. The application of compound codes to the WOM
system is new. The main result is that spatial coupling
enables these codes to achieve the capacity region of the
2-write WOM system with low-complexity message-passing
encoding and decoding algorithms.},
Doi = {10.1109/ALLERTON.2015.7446994},
Key = {fds322716}
}

@article{fds322717,
Author = {Lian, M and Pfister, HD},
Title = {Belief-propagation reconstruction for compressed sensing:
Quantization vs. Gaussian approximation},
Journal = {2015 53rd Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2015},
Pages = {1106-1113},
Publisher = {IEEE},
Year = {2016},
Month = {April},
ISBN = {9781509018239},
url = {http://dx.doi.org/10.1109/ALLERTON.2015.7447132},
Abstract = {© 2015 IEEE. This work considers the compressed sensing
(CS) of i.i.d. signals with sparse measurement matrices and
belief-propagation (BP) reconstruction. In general, BP
reconstruction for CS requires the passing of messages that
are distributions over the real numbers. To implement this
in practice, one typically uses either quantized
distributions or a Gaussian approximation. In this work, we
use density evolution to compare the reconstruction
performance of these two methods. Since the reconstruction
performance depends on the signal realization, this analysis
makes use of a novel change of variables to analyze the
performance for a typical signal. Simulation results are
provided to support the results.},
Doi = {10.1109/ALLERTON.2015.7447132},
Key = {fds322717}
}

@article{fds323532,
Author = {Kudekar, S and Kumar, S and Mondelli, M and Pfister, HD and Sasoglu, E and Urbanke, RL},
Title = {Reed-Muller codes achieve capacity on erasure
channels.},
Journal = {Stoc},
Pages = {658-669},
Publisher = {ACM},
Editor = {Wichs, D and Mansour, Y},
Year = {2016},
ISBN = {978-1-4503-4132-5},
url = {http://dx.doi.org/10.1145/2897518.2897584},
Doi = {10.1145/2897518.2897584},
Key = {fds323532}
}

@article{fds319314,
Author = {Hamidi-Sepehr, F and Chamberland, JF and Pfister,
HD},
Title = {On the Performance of Block Codes over Finite-State Channels
in the Rare-Transition Regime},
Journal = {Ieee Transactions on Communications},
Volume = {63},
Number = {11},
Pages = {3974-3990},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2015},
Month = {November},
url = {http://dx.doi.org/10.1109/TCOMM.2015.2478794},
supporting different connection profiles, including
real-time traffic and delay-sensitive communications. This
creates a need to better understand the fundamental limits
of forward error correction in non-asymptotic regimes. This
paper characterizes the performance of block codes over
finite-state channels and evaluates their queueing
performance under maximum-likelihood decoding. Classical
results from digital communications are revisited in the
context of channels with rare transitions, and bounds on the
probabilities of decoding failure are derived for random
codes. This creates an analysis framework where channel
dependencies within and across codewords are preserved.
These results are subsequently integrated into a queueing
problem formulation.},
Doi = {10.1109/TCOMM.2015.2478794},
Key = {fds319314}
}

@article{fds319315,
Author = {Pfister, HD and Emmadi, SK and Narayanan, K},
Title = {Symmetric product codes},
Journal = {2015 Information Theory and Applications Workshop, Ita 2015
Conference Proceedings},
Pages = {282-290},
Publisher = {IEEE},
Year = {2015},
Month = {October},
ISBN = {9781479971954},
url = {http://dx.doi.org/10.1109/ITA.2015.7309002},
Abstract = {© 2015 IEEE. Product codes were introduced by Elias in 1954
and generalized by Tanner in 1981. Recently, a number of
generalized product codes have been proposed for forward
error-correction in high-speed optical communication. In
practice, these codes are decoded by iteratively decoding
each of the component codes. Symmetric product codes are a
subclass of generalized product codes that use symmetry to
reduce the block length of a product code while using the
same component code. One example of this subclass, dubbed
half-product codes, was introduced by Tanner in 1981 and
then generalized by Justesen in 2011. In this paper, we
discuss some initial results on symmetric product codes. Our
results show that: (i) these codes have a larger normalized
minimum distance than the product code from which they are
derived, (ii) some small constructions achieve the largest
minimum distance possible for a linear code, and (iii) they
can have better performance in both the waterfall region and
the error floor when compared to a product code of similar
length and rate.},
Doi = {10.1109/ITA.2015.7309002},
Key = {fds319315}
}

@article{fds319316,
Author = {Li, S and Huang, YC and Liu, T and Pfister, HD},
Title = {On the limits of treating interference as noise for two-user
symmetric Gaussian interference channels},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2015-June},
Pages = {1711-1715},
Publisher = {IEEE},
Year = {2015},
Month = {September},
ISBN = {9781467377041},
url = {http://dx.doi.org/10.1109/ISIT.2015.7282748},
Abstract = {© 2015 IEEE. The limits of treating interference as noise
are studied for the canonical two-user symmetric Gaussian
interference channel. A two-step approach is proposed for
finding approximately optimal input distributions in the
high signal-to-noise ratio (SNR) regime. First,
approximately and precisely optimal input distributions are
found for the Avestimehr-Diggavi-Tse (ADT) linear
deterministic model. These distributions are then
translated, systematically, into Gaussian models, which we
show can achieve the sum capacity to within O(log
log(SNR)).},
Doi = {10.1109/ISIT.2015.7282748},
Key = {fds319316}
}

@article{fds319317,
Author = {Rengaswamy, N and Pfister, HD},
Title = {Cyclic polar codes},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Volume = {2015-June},
Pages = {1287-1291},
Publisher = {IEEE},
Year = {2015},
Month = {September},
ISBN = {9781467377041},
url = {http://dx.doi.org/10.1109/ISIT.2015.7282663},
Abstract = {© 2015 IEEE. Arikan introduced polar codes in 2009 and
proved that they achieve the symmetric capacity, under
low-complexity successive cancellation decoding, of any
binary-input discrete memoryless channel. Arikan's
construction is based on the Kronecker product of 2-by-2
matrices and it was extended to larger matrices by
Şaşoǧlu et al. in 2010. In this paper, we construct
cyclic polar codes based on a mixed-radix Cooley-Tukey
decomposition of the Galois field Fourier transform.
Ignoring the twiddle factors between stages, the derived
fast Fourier transform is essentially a Kronecker product of
small Fourier transform matrices. Thus, one can define a
successive cancellation decoder and observe that the
coordinate channels polarize. Choosing the locations of the
frozen symbols in the resulting polar code is identical to
choosing the locations of zeros in the Fourier transform of
the codewords and, thus, the code is cyclic.},
Doi = {10.1109/ISIT.2015.7282663},
Key = {fds319317}
}

@article{fds319318,
Author = {Hamidi-Sepehr, F and Pfister, HD and Chamberland,
JF},
Title = {Delay-Sensitive Communication over Fading Channels: Queueing
Behavior and Code Parameter Selection},
Journal = {Ieee Transactions on Vehicular Technology},
Volume = {64},
Number = {9},
Pages = {3957-3970},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2015},
Month = {September},
url = {http://dx.doi.org/10.1109/TVT.2014.2365181},
Abstract = {© 1967-2012 IEEE. This paper examines the queueing
performance of communication systems that transmit encoded
data over unreliable channels. A fading formulation suitable
for wireless mobile applications is considered, where errors
are caused by a discrete channel with correlated behavior
over time. For carefully selected channel models and arrival
processes, a tractable Markov structure composed of queue
length and channel state is identified. This facilitates the
analysis of the stationary behavior of the system, leading
to evaluation criteria such as bounds on the probability of
the queue exceeding a threshold. Specifically, this paper
focuses on system models with scalable arrival profiles,
which are based on Poisson processes, and finite-state
channels with memory. These assumptions permit the rigorous
comparison of system performance for codes with arbitrary
block lengths and code rates. Based on the resulting
characterizations, it is possible to select the best code
parameters for delay-sensitive applications over various
channels. Random codes and BCH codes are then employed as a
means to study the relationship between code parameter
selection and the queueing performance of point-to-point
data links. The methodology introduced herein offers a new
perspective on the joint queueing-coding analysis of
finite-state channels with memory, and it is supported by
numerical simulations.},
Doi = {10.1109/TVT.2014.2365181},
Key = {fds319318}
}

@article{fds319319,
Author = {Häger, C and i Amat, AG and Pfister, HD and Alvarado, A and Brännström, F and Agrell, E},
Title = {On parameter optimization for staircase codes},
Journal = {Optical Fiber Communication Conference, Ofc
2015},
Year = {2015},
Month = {January},
ISBN = {9781557529374},
Abstract = {© OSA 2015. We discuss the optimization of staircase code
parameters based on density evolution. An extension of the
original code construction is proposed, leading to codes
with steeper waterfall performance.},
Key = {fds319319}
}

@article{fds319320,
Author = {Hager, C and Amat, AGI and Pfister, HD and Alvarado, A and Brannstrom,
F and Agrell, E},
Title = {On parameter optimization for staircase codes},
Journal = {Conference on Optical Fiber Communication, Technical Digest
Series},
Volume = {2015-June},
Year = {2015},
Month = {January},
ISBN = {9781557529374},
Abstract = {© 2015 OSA. We discuss the optimization of staircase code
parameters based on density evolution. An extension of the
original code construction is proposed, leading to codes
with steeper waterfall performance.},
Key = {fds319320}
}

@article{fds319323,
Author = {Kumar, S and Young, AJ and Macris, N and Pfister,
HD},
Title = {Threshold saturation for spatially coupled LDPC and LDGM
codes on BMS channels},
Journal = {Ieee Transactions on Information Theory},
Volume = {60},
Number = {12},
Pages = {7389-7415},
Year = {2014},
Month = {December},
url = {http://dx.doi.org/10.1109/TIT.2014.2360692},
Abstract = {© 2014 IEEE. Spatially-coupled low-density parity-check
(LDPC) codes, which were first introduced as LDPC
convolutional codes, have been shown to exhibit excellent
performance under low-complexity belief-propagation
decoding. This phenomenon is now termed threshold saturation
via spatial coupling. Spatially-coupled codes have been
successfully applied in numerous areas. In particular, it
was proven that spatially-coupled regular LDPC codes
universally achieve capacity over the class of binary
memoryless symmetric (BMS) channels under belief-propagation
decoding. Recently, potential functions have been used to
simplify threshold saturation proofs for scalar and vector
recursions. In this paper, potential functions are used to
prove threshold saturation for irregular LDPC and
low-density generator-matrix codes on BMS channels,
extending the simplified proof technique to BMS channels.
The corresponding potential functions are closely related to
the average Bethe free entropy of the ensembles in the
large-system limit. These functions also appear in
statistical physics when the replica method is used to
analyze optimal decoding.},
Doi = {10.1109/TIT.2014.2360692},
Key = {fds319323}
}

@article{fds319324,
Author = {Yedla, A and Jian, YY and Nguyen, PS and Pfister,
HD},
Title = {A simple proof of maxwell saturation for coupled scalar
recursions},
Journal = {Ieee Transactions on Information Theory},
Volume = {60},
Number = {11},
Pages = {6943-6965},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2014},
Month = {January},
url = {http://dx.doi.org/10.1109/TIT.2014.2352296},
Abstract = {© 2014 IEEE. Low-density parity-check (LDPC) convolutional
codes (or spatially coupled codes) were recently shown to
approach capacity on the binary erasure channel (BEC) and
binary-input memoryless symmetric channels. The mechanism
behind this spectacular performance is now called threshold
saturation via spatial coupling. This new phenomenon is
characterized by the belief-propagation threshold of the
spatially coupled ensemble increasing to an intrinsic noise
threshold defined by the uncoupled system. In this paper, we
present a simple proof of threshold saturation that applies
to a wide class of coupled scalar recursions. Our approach
is based on constructing potential functions for both the
coupled and uncoupled recursions. Our results actually show
that the fixed point of the coupled recursion is essentially
determined by the minimum of the uncoupled potential
function and we refer to this phenomenon as Maxwell
saturation. A variety of examples are considered including
the density-evolution equations for: irregular LDPC codes on
the BEC, irregular low-density generator-matrix codes on the
BEC, a class of generalized LDPC codes with BCH component
codes, the joint iterative decoding of LDPC codes on
intersymbol-interference channels with erasure noise, and
the compressed sensing of random vectors with independent
identically distributed components.},
Doi = {10.1109/TIT.2014.2352296},
Key = {fds319324}
}

@article{fds319325,
Author = {Jian, YY and Pfister, HD},
Title = {Convergence of weighted min-sum decoding via dynamic
programming on trees},
Journal = {Ieee Transactions on Information Theory},
Volume = {60},
Number = {2},
Pages = {943-963},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2014},
Month = {January},
url = {http://dx.doi.org/10.1109/TIT.2013.2290303},
Abstract = {Applying the max-product (and sum-product) algorithms to
loopy graphs is now quite popular for best assignment
problems. This is largely due to their low computational
complexity and impressive performance in practice. Still,
there is no general understanding of the conditions required
for convergence or optimality of converged solutions or
both. This paper presents an analysis of both attenuated
max-product decoding and weighted min-sum decoding for
low-density paritycheck (LDPC) codes, which guarantees
convergence to a fixed point when a weight factor, β is
sufficiently small. It also shows that, if the fixed point
satisfies some consistency conditions, then it must be both
a linear-programming (LP) and maximumlikelihood (ML)
decoding solution. For (dv, dc)-regular LDPC codes, the
Doi = {10.1109/TIT.2013.2290303},
Key = {fds319325}
}

@article{fds319326,
Author = {Vem, A and Huang, YC and Narayanan, KR and Pfister,
HD},
Title = {Multilevel lattices based on spatially-coupled LDPC codes
with applications},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {2336-2340},
Publisher = {IEEE},
Year = {2014},
Month = {January},
ISBN = {9781479951864},
url = {http://dx.doi.org/10.1109/ISIT.2014.6875251},
Abstract = {We propose a class of lattices constructed using
Construction D where the underlying linear codes are nested
binary spatially-coupled low-density parity-check codes
(SC-LDPC) codes with uniform left and right degrees. By
leveraging recent results on the optimality of
spatially-coupled codes for binary input memoryless channels
and Forney et al.'s earlier results on the optimality of
construction D, we show that the proposed lattices achieve
the Poltyrev limit under multistage belief propagation
decoding. Lattice codes constructed from these lattices are
shown to provide excellent performance for the three user
symmetric interference channel. They can also be naturally
used in applications such as integer-forcing and
Doi = {10.1109/ISIT.2014.6875251},
Key = {fds319326}
}

@article{fds319327,
Author = {Kumar, S and Vem, A and Narayanan, K and Pfister,
HD},
Title = {Spatially-coupled codes for side-information
problems},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {516-520},
Publisher = {IEEE},
Year = {2014},
Month = {January},
ISBN = {9781479951864},
url = {http://dx.doi.org/10.1109/ISIT.2014.6874886},
Abstract = {For compound LDGM/LDPC codes with maximum a posteriori (MAP)
processing, Wainwright and Martinian showed that the
information-theoretic rate regions of the Wyner-Ziv (WZ) and
Gelfand-Pinsker (GP) problems are achievable. For the same
ensemble, these rates do not appear to be achievable with
message-passing guided decimation (GD). Fortunately,
spatially-coupled (SC) codes seem to provide an elegant
remedy when iterative decoding falls short of MAP decoding.
In particular, Aref et al. recently introduced SC LDGM codes
that approach the rate-distortion region with
belief-propagation guided decimation (BPGD). In this paper,
we show that SC compound LDGM/LDPC codes with BPGD can
approach the rate regions of the WZ and GP problems. © 2014
IEEE.},
Doi = {10.1109/ISIT.2014.6874886},
Key = {fds319327}
}

@article{fds319328,
Author = {Pfister, HD and Narayanan, KR},
Title = {An introduction to spatially-coupled codes via practical
examples},
Journal = {2014 31th Ursi General Assembly and Scientific Symposium,
Ursi Gass 2014},
Publisher = {IEEE},
Year = {2014},
Month = {January},
ISBN = {9781467352253},
url = {http://dx.doi.org/10.1109/URSIGASS.2014.6929240},
Abstract = {© 2014 IEEE. This paper uses examples to illustrate the
ongoing transition in spatially-coupled coding from theory
to practice. In the first example, we find that
spatially-coupled codes have already been implemented by two
different companies for 100 Gb/s optical communications.
Both systems use variants of braided block codes, which were
introduced even before the term spatial coupling. In the
second example, we discuss the multiple-access channel and
observe that some gains from spatial coupling were being
realized in cellular base stations as early as 2007.
Finally, we discuss some open questions regarding
spatially-coupled codes.},
Doi = {10.1109/URSIGASS.2014.6929240},
Key = {fds319328}
}

@article{fds319332,
Author = {Pfister, HD and Vontobel, PO},
Title = {On the relevance of graph covers and zeta functions for the
analysis of SPA decoding of cycle codes},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {3000-3004},
Publisher = {IEEE},
Year = {2013},
Month = {December},
ISBN = {9781479904464},
url = {http://dx.doi.org/10.1109/ISIT.2013.6620776},
Abstract = {For an arbitrary binary cycle code, we show that sum-product
algorithm (SPA) decoding after infinitely many iterations
equals symbolwise graph-cover decoding. We do this by
characterizing the Bethe free energy function of the
underlying normal factor graph (NFG) and by stating a global
convergence proof of the SPA. We also show that the set of
log-likelihood ratio vectors for which the SPA converges to
the all-zero codeword is given by the region of convergence
of the edge zeta function associated with the underlying
NFG. The results in this paper justify the use of
graph-cover pseudo-codewords and edge zeta functions to
characterize the behavior of SPA decoding of cycle codes.
These results have also implications for the analysis of
attenuated sum-product and max-product algorithm decoding of
low-density parity-check (LDPC) codes beyond cycle codes. ©
2013 IEEE.},
Doi = {10.1109/ISIT.2013.6620776},
Key = {fds319332}
}

@article{fds319333,
Author = {Obata, N and Jian, YY and Kasai, K and Pfister, HD},
Title = {Spatially-coupled multi-edge type LDPC codes with bounded
degrees that achieve capacity on the BEC under BP
decoding},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {2433-2437},
Publisher = {IEEE},
Year = {2013},
Month = {December},
ISBN = {9781479904464},
url = {http://dx.doi.org/10.1109/ISIT.2013.6620663},
Abstract = {Convolutional (or spatially-coupled) low-density
parity-check (LDPC) codes have now been shown to approach
capacity for a variety of problems. Yet, most of these
results require sequences of regular LDPC ensembles with
increasing variable and check degrees. Previously, Kasai and
Sakaniwa showed empirically that, for the BEC, this
limitation can be overcome by using spatially-coupled
MacKay-Neal (MN) and Hsu-Anastasopoulos (HA) ensembles. In
this paper, we prove this analytically for (k, 2, 2)-MN and
(2, k, 2)-HA ensembles when k is at least 3. The proof is
based on the simple approach to threshold saturation,
introduced by Yedla et al., which relies on potential
functions. The key step is verifying the non-negativity of a
potential function associated with the uncoupled system.
Along the way, we derive the potential function general
multi-edge type (MET) LDPC ensembles and establish a duality
relationship between dual ensembles of MET LDPC codes. ©
2013 IEEE.},
Doi = {10.1109/ISIT.2013.6620663},
Key = {fds319333}
}

@article{fds319334,
Author = {Tunali, NE and Narayanan, KR and Pfister, HD},
Title = {Spatially-coupled low density lattices based on construction
a with applications to compute-and-forward},
Journal = {2013 Ieee Information Theory Workshop, Itw
2013},
Publisher = {IEEE},
Year = {2013},
Month = {December},
ISBN = {9781479913237},
url = {http://dx.doi.org/10.1109/ITW.2013.6691275},
Abstract = {We consider a class of lattices built using Construction A,
where the underlying code is a non-binary spatially-coupled
low density parity check code. We refer to these lattices as
spatially-coupled LDA (SCLDA) lattices. SCLDA lattices can
be constructed over integers, Gaussian integers and
Eisenstein integers. We empirically study the performance of
SCLDA lattices under belief propagation (BP) decoding.
Ignoring the rate loss from termination, simulation results
show that the BP thresholds of SCLDA lattices over integers
is 0.11 dB (0.34 dB with the rate loss) and the BP
thresholds for SCLDA lattices over Eisenstein integers are
0.08 dB from the Poltyrev limit (0.19 dB with the rate
loss). Motivated by this result, we use SCLDA lattice codes
over Eisenstein integers for implementing a
compute-and-forward protocol. For the examples considered in
this paper, the thresholds for the proposed lattice codes
are within 0.28 dB from the achievable rate of this coding
scheme and within 1.06 dB from the achievable computation
rate of Nazer and Gastpar's coding scheme in [6] extended to
Doi = {10.1109/ITW.2013.6691275},
Key = {fds319334}
}

@article{fds319335,
Author = {Kumar, S and Chamberland, JF and Pfister, HD},
Title = {First-passage time and large-deviation analysis for erasure
channels with memory},
Journal = {Ieee Transactions on Information Theory},
Volume = {59},
Number = {9},
Pages = {5547-5565},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2013},
Month = {August},
url = {http://dx.doi.org/10.1109/TIT.2013.2260593},
Abstract = {This paper considers the performance of digital
communication systems transmitting messages over
finite-state erasure channels with memory. Information bits
are protected from channel erasures using error-correcting
codes; successful receptions of codewords are acknowledged
at the source through instantaneous feedback. The primary
focus of this research is on delay-sensitive applications,
codes with finite block lengths, and, necessarily,
nonvanishing probabilities of decoding failure. The
contribution of this paper is twofold. A methodology to
compute the distribution of the time required to empty a
buffer is introduced. Based on this distribution, the mean
hitting time to an empty queue and delay-violation
probabilities for specific thresholds can be computed
explicitly. The proposed techniques apply to situations
where the transmit buffer contains a predetermined number of
information bits at the onset of the data transfer.
Furthermore, as additional performance criteria, large
deviation principles are obtained for the empirical mean
service time and the average packet-transmission time
associated with the communication process. This rigorous
framework yields a pragmatic methodology to select code rate
and block length for the communication unit as functions of
the service requirements. Examples motivated by practical
systems are provided to further illustrate the applicability
of these techniques. © 1963-2012 IEEE.},
Doi = {10.1109/TIT.2013.2260593},
Key = {fds319335}
}

@article{fds319336,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {Code design for the noisy Slepian-Wolf problem},
Journal = {Ieee Transactions on Communications},
Volume = {61},
Number = {6},
Pages = {2535-2545},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2013},
Month = {June},
url = {http://dx.doi.org/10.1109/TCOMM.2013.032713.120002A},
Abstract = {© 2013 IEEE. We consider a noisy Slepian-Wolf problem where
two correlated sources are separately encoded (using codes
of fixed rate) and transmitted over two independent binary
memoryless symmetric channels. The capacity of each channel
is characterized by a single parameter that is not known at
the transmitter. System performance is evaluated by
computing the set of channel parameters for which the system
can successfully decode. This set is called the achievable
channel parameter region (ACPR). The goal is to design
systems whose ACPRs are as large as possible. The main
result is the design of irregular low-density paritycheck
(LDPC) ensembles whose ACPRs are significantly larger than
previous designs. Some previous attempts to achieve large
ACPRs with LDPC codes failed because systematic codes were
puncture all the systematic bits before transmission. We
also show that additional gains are possible using a
staggered structure which enables codes optimized for
single-user channels to perform well under symmetric channel
conditions. The main analysis tool is a generic
density-evolution framework for the analysis of joint
iterative decoding for this problem.},
Doi = {10.1109/TCOMM.2013.032713.120002A},
Key = {fds319336}
}

@article{fds319338,
Author = {Parag, P and Chamberland, JF and Pfister, HD and Narayanan,
K},
Title = {Code-rate selection, queueing behavior, and the correlated
erasure channel},
Journal = {Ieee Transactions on Information Theory},
Volume = {59},
Number = {1},
Pages = {397-407},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2013},
Month = {January},
url = {http://dx.doi.org/10.1109/TIT.2012.2216501},
Abstract = {This paper considers the relationship between code-rate
selection and queueing performance for communication systems
subject to time-varying channel conditions. While
error-correcting codes offer protection against channel
uncertainties, there exists a natural tradeoff between the
enhanced protection of low-rate codes and the rate penalty
imposed by additional redundancy. In the limiting regime
where codewords are asymptotically long, this tradeoff is
well understood and characterized by the Shannon capacity.
However, for delay-sensitive communication systems and
finite block lengths, a complete characterization of this
tradeoff is not fully developed. This paper offers a new
perspective on the queueing performance of communication
systems with finite block lengths operating over correlated
erasure channels. A rigorous framework that links code rate
to overall system performance for random codes is presented.
Guidelines for code-rate selection in delay-sensitive
systems are identified. These findings are supported by a
Doi = {10.1109/TIT.2012.2216501},
Key = {fds319338}
}

@article{fds319337,
Author = {Jian, YY and Pfister, HD and Narayanan, KR and Rao, R and Mazahreh,
R},
Title = {Iterative hard-decision decoding of braided BCH codes for
high-speed optical communication},
Journal = {Globecom Ieee Global Telecommunications Conference},
Pages = {2376-2381},
Publisher = {IEEE},
Year = {2013},
Month = {January},
ISBN = {9781479913534},
url = {http://dx.doi.org/10.1109/GLOCOM.2013.6831429},
Abstract = {Designing error-correcting codes for optical communication
is challenging mainly because of the high data rates (e.g.,
100 Gbps) required and the expectation of low latency, low
overhead (e.g., 7% redundancy), and large coding gain (e.g.,
>9dB). Although soft-decision decoding (SDD) of low-density
parity-check (LDPC) codes is an active area of research, the
mainstay of optical transport systems is still the iterative
hard-decision decoding (HDD) of generalized product codes
with algebraic syndrome decoding of the component codes.
This is because iterative HDD allows many simplifications
and SDD of LDPC codes results in much higher implementation
complexity. In this paper, we use analysis and simulation to
evaluate tightly-braided block codes with BCH component
codes for high-speed optical communication. Simulation of
the iterative HDD shows that these codes are competitive
with the best schemes based on HDD. Finally, we suggest a
specific design that is compatible with the G.709 framing
structure and exhibits a coding gain of >9.35 dB at 7%
redundancy under iterative HDD with a latency of
approximately 1 million bits. © 2013 IEEE.},
Doi = {10.1109/GLOCOM.2013.6831429},
Key = {fds319337}
}

@article{fds319340,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {Code Design for the Noisy Slepian-Wolf Problem.},
Journal = {Ieee Trans. Communications},
Volume = {61},
Pages = {2535-2545},
Year = {2013},
url = {http://dx.doi.org/10.1109/TCOMM.2013.032713.120002A},
Doi = {10.1109/TCOMM.2013.032713.120002A},
Key = {fds319340}
}

@article{fds319341,
Author = {Kumar, S and Young, AJ and Macris, N and Pfister,
HD},
Title = {A Proof of Threshold Saturation for Spatially-Coupled LDPC
Codes on BMS Channels},
Volume = {abs/1301.6111},
Year = {2013},
Key = {fds319341}
}

@article{fds319342,
Author = {Yedla, A and Jian, YY and Nguyen, PS and Pfister,
HD},
Title = {A simple proof of threshold saturation for coupled scalar
recursions},
Journal = {International Symposium on Turbo Codes and Iterative
Information Processing, Istc},
Pages = {51-55},
Year = {2012},
Month = {December},
ISBN = {9781457721151},
url = {http://dx.doi.org/10.1109/ISTC.2012.6325197},
Abstract = {Low-density parity-check (LDPC) convolutional codes (or
spatially-coupled codes) have been shown to approach
capacity on the binary erasure channel (BEC) and
binary-input memoryless symmetric channels. The mechanism
behind this spectacular performance is the threshold
saturation phenomenon, which is characterized by the
belief-propagation threshold of the spatially-coupled
ensemble increasing to an intrinsic noise threshold defined
by the uncoupled system. In this paper, we present a simple
proof of threshold saturation that applies to a broad class
of coupled scalar recursions. The conditions of the theorem
are verified for the density-evolution (DE) equations of
irregular LDPC codes on the BEC, a class of generalized LDPC
codes, and the joint iterative decoding of LDPC codes on
intersymbol-interference channels with erasure noise. Our
approach is based on potential functions and was motivated
mainly by the ideas of Takeuchi et al. The resulting proof
is surprisingly simple when compared to previous methods. ©
2012 IEEE.},
Doi = {10.1109/ISTC.2012.6325197},
Key = {fds319342}
}

@article{fds319343,
Author = {Narayanan, KR and Pfister, HD},
Title = {Iterative collision resolution for slotted ALOHA: An optimal
uncoordinated transmission policy},
Journal = {International Symposium on Turbo Codes and Iterative
Information Processing, Istc},
Pages = {136-139},
Publisher = {IEEE},
Year = {2012},
Month = {December},
ISBN = {9781457721151},
url = {http://dx.doi.org/10.1109/ISTC.2012.6325214},
Abstract = {We consider a multi-user wireless network in which each user
has one packet of information to transmit to a central
send their packet a random number of times according to a
packets, the receiver performs iterative collision
resolution. Recently, a few studies have shown that the
iterative collision resolution process can be viewed as
message-passing decoding on an appropriately defined Tanner
graph. Using this equivalence, they used standard techniques
to numerically optimize the probability distribution and
demonstrated substantial throughput improvement over slotted
ALOHA. In this paper, we show that the well-known soliton
distribution is an optimal probability distribution and that
the resulting throughput efficiency can be arbitrarily close
Doi = {10.1109/ISTC.2012.6325214},
Key = {fds319343}
}

@article{fds319347,
Author = {Kumar, S and Young, AJ and Maoris, N and Pfister,
HD},
Title = {A proof of threshold saturation for spatially-coupled LDPC
codes on BMS channels},
Journal = {2012 50th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2012},
Pages = {176-184},
Publisher = {IEEE},
Year = {2012},
Month = {December},
ISBN = {9781467345385},
url = {http://dx.doi.org/10.1109/Allerton.2012.6483215},
Abstract = {Low-density parity-check (LDPC) convolutional codes have
been shown to exhibit excellent performance under
low-complexity belief-propagation decoding [1], [2]. This
phenomenon is now termed threshold saturation via spatial
coupling. The underlying principle behind this appears to be
very general and spatially-coupled (SC) codes have been
successfully applied in numerous areas. Recently, SC regular
LDPC codes have been proven to achieve capacity universally,
over the class of binary memoryless symmetric (BMS)
channels, under belief-propagation decoding [3], [4]. In
[5], [6], potential functions are used to prove that the BP
threshold of SC irregular LDPC ensembles saturates, for the
binary erasure channel, to the conjectured MAP threshold
(known as the Maxwell threshold) of the underlying irregular
ensembles. In this paper, that proof technique is
generalized to BMS channels, thereby extending some results
of [4] to irregular LDPC ensembles. We also believe that
this approach can be expanded to cover a wide class of
graphical models whose message-passing rules are associated
with a Bethe free energy. © 2012 IEEE.},
Doi = {10.1109/Allerton.2012.6483215},
Key = {fds319347}
}

@article{fds319344,
Author = {Yedla, A and Jian, YY and Nguyen, PS and Pfister,
HD},
Title = {A simple proof of threshold saturation for coupled vector
recursions},
Journal = {2012 Ieee Information Theory Workshop, Itw
2012},
Pages = {25-29},
Publisher = {IEEE},
Year = {2012},
Month = {December},
ISBN = {9781467302234},
url = {http://dx.doi.org/10.1109/ITW.2012.6404671},
Abstract = {Convolutional low-density parity-check (LDPC) codes (or
spatially-coupled codes) have now been shown to achieve
capacity on binary-input memoryless symmetric channels. The
principle behind this surprising result is the
threshold-saturation phenomenon, which is defined by the
belief-propagation threshold of the spatially-coupled
ensemble saturating to a fundamental threshold defined by
the uncoupled system. Previously, the authors demonstrated
that potential functions can be used to provide a simple
proof of threshold saturation for coupled scalar recursions.
In this paper, we present a simple proof of threshold
saturation that applies to a wide class of coupled vector
recursions. The conditions of the theorem are verified for
the density-evolution equations of: (i) joint decoding of
irregular LDPC codes for a Slepian-Wolf problem with
erasures, (ii) joint decoding of irregular LDPC codes on an
erasure multiple-access channel, and (iii) admissible
protograph codes on the BEC. This proves threshold
saturation for these systems. © 2012 IEEE.},
Doi = {10.1109/ITW.2012.6404671},
Key = {fds319344}
}

@article{fds319345,
Author = {Hamidi-Sepehr, F and Chamberland, JF and Pfister,
HD},
Title = {On the performance of random block codes over finite-state
Journal = {2012 50th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2012},
Pages = {17-25},
Publisher = {IEEE},
Year = {2012},
Month = {December},
ISBN = {9781467345385},
url = {http://dx.doi.org/10.1109/Allerton.2012.6483194},
Abstract = {As the mobile application landscape expands, wireless
networks are tasked with supporting different connection
profiles, including real-time traffic and delay-sensitive
communications. Among many ensuing engineering challenges is
the need to better understand the fundamental limits of
forward error correction in non-asymptotic regimes. This
article seeks to characterize the performance of block codes
over finite-state channels with memory. In particular,
classical results from information theory are revisited in
the context of channels with rare transitions, and bounds on
the probabilities of decoding failure are derived for random
codes. This creates an analysis framework where channel
dependencies within and across codewords are preserved. Such
results can subsequently be integrated into a queueing
problem formulation. Overall, this study offers new insights
about the potential impact of channel correlation on the
performance of delay-aware, point-to-point communication
Doi = {10.1109/Allerton.2012.6483194},
Key = {fds319345}
}

@article{fds319346,
Author = {Nguyen, PS and Yedla, A and Pfister, HD and Narayanan,
KR},
Title = {Threshold saturation of spatially-coupled codes on
intersymbol-interference channels},
Journal = {Ieee International Conference on Communications},
Pages = {2181-2186},
Publisher = {IEEE},
Year = {2012},
Month = {December},
ISBN = {9781457720529},
url = {http://dx.doi.org/10.1109/ICC.2012.6364433},
Abstract = {Recently, it has been observed that terminated
low-density-parity-check (LDPC) convolutional codes (or
spatially-coupled codes) appear to approach the capacity
universally across the class of binary memoryless channels.
This is facilitated by the 'threshold saturation' effect
whereby the belief-propagation (BP) threshold of the
spatially-coupled ensemble is boosted to the maximum
a-posteriori (MAP) threshold of the underlying constituent
ensemble. In this paper, we consider spatially-coupled codes
over intersymbol-interference (ISI) channels under joint
iterative decoding where we empirically show that threshold
saturation also occurs. This can be observed by first
identifying the GEXIT curve that naturally obeys the general
area theorem. From this curve, the corresponding MAP and the
BP threshold estimates are then numerically obtained. Given
the fact that regular LDPC codes can achieve the symmetric
information rate (SIR) under MAP decoding, we conjecture
that spatially-coupled codes with joint iterative decoding
can universally approach the SIR of ISI channels. © 2012
IEEE.},
Doi = {10.1109/ICC.2012.6364433},
Key = {fds319346}
}

@article{fds319348,
Author = {Hamidi-Sepehr, F and Pfister, HD and Chamberland,
JF},
Title = {On the queueing behavior of Gilbert-Elliott channels in the
rare-transition regime},
Journal = {2012 46th Annual Conference on Information Sciences and
Systems, Ciss 2012},
Publisher = {IEEE},
Year = {2012},
Month = {November},
ISBN = {9781467331401},
url = {http://dx.doi.org/10.1109/CISS.2012.6310913},
over the Gilbert-Elliott channel and characterizes the
queueing performance under maximum-likelihood decoding. The
probability of decoding failure is upper bounded using an
approximation that works well in the rare-transition regime
and the bound is used to perform a queueing analysis. A
Poisson arrival process is chosen to allow fair comparisons
between different block lengths and code rates. A Markov
chain, based on the queue length and channel state, is
constructed and used to analyze the tail probability of the
queue. Our methods are used to evaluate both the probability
of decoding failure, under a constraint of the probability
of undetected error, and the queueing performance. The main
result is that, for random coding on the Gilbert-Elliott
channel, the performance analysis based on upper bounds
provides a very good estimate of both the system performance
and the optimum code parameters. © 2012
IEEE.},
Doi = {10.1109/CISS.2012.6310913},
Key = {fds319348}
}

@article{fds319349,
Author = {Jian, YY and Pfister, HD and Narayanan, KR},
Title = {Approaching capacity at high rates with iterative
hard-decision decoding},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {2696-2700},
Publisher = {IEEE},
Year = {2012},
Month = {October},
ISBN = {9781467325790},
url = {http://dx.doi.org/10.1109/ISIT.2012.6284009},
Abstract = {A variety of low-density parity-check (LDPC) ensembles have
now been observed to approach capacity with message-passing
decoding. However, all of them use soft (i.e., non-binary)
messages and a posteriori probability (APP) decoding of
their component codes. In this paper, we analyze a class of
spatially-coupled generalized LDPC codes and observe that,
in the high-rate regime, they can approach capacity under
iterative hard-decision decoding. These codes can be seen as
generalized product codes and are closely related to braided
Doi = {10.1109/ISIT.2012.6284009},
Key = {fds319349}
}

@article{fds319350,
Author = {Nguyen, PS and Yedla, A and Pfister, HD and Narayanan,
KR},
Title = {On the maximum a posteriori decoding thresholds of multiuser
systems with erasures},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {2701-2705},
Publisher = {IEEE},
Year = {2012},
Month = {October},
ISBN = {9781467325790},
url = {http://dx.doi.org/10.1109/ISIT.2012.6284013},
Abstract = {A fundamental connection between the belief propagation (BP)
and maximum a posteriori (MAP) decoding thresholds was
derived by Méasson, Montanari, and Urbanke using the area
theorem for extrinsic information transfer (EXIT) curves.
This connection allows the MAP threshold, for the binary
erasure channel, to be evaluated efficiently via an upper
bound that can be shown to be tight in some cases. In this
paper, a similar analysis is used to extend these results to
several multiuser systems, namely a noisy Slepian-Wolf
problem and a multiple-access channel with erasures. The
simplicity of these channel models allows for rigorous
analysis and enables the derivation of upper bounds on the
MAP thresholds using EXIT area theorems. In some cases, one
can also show these bounds are tight. One interesting
application is that the MAP thresholds can be compared with
the BP thresholds of spatially-coupled codes to verify
threshold saturation for the corresponding systems. © 2012
IEEE.},
Doi = {10.1109/ISIT.2012.6284013},
Key = {fds319350}
}

@article{fds319351,
Author = {Zhang, F and Pfister, HD},
Title = {Verification decoding of high-rate ldpc codes with
applications in compressed sensing},
Journal = {Ieee Transactions on Information Theory},
Volume = {58},
Number = {8},
Pages = {5042-5058},
Year = {2012},
Month = {July},
url = {http://dx.doi.org/10.1109/TIT.2012.2201344},
Abstract = {This paper considers the performance of (j,k)-regular
low-density parity-check (LDPC) codes with message-passing
(MP) decoding algorithms in the high-rate regime. In
particular, we derive the high-rate scaling law for MP
decoding of LDPC codes on the binary erasure channel (BEC)
and the q -ary symmetric channel (q-SC). For the BEC and a
fixed j, the density evolution (DE) threshold of iterative
decoding scales like \Theta (k^{-1}) and the critical
stopping ratio scales like \Theta (k^{-j/(j-2)}). For the
q-SC and a fixed j, the DE threshold of verification
decoding depends on the details of the decoder and scales
like \Theta (k^{-1}) for one decoder. Using the fact that
coding over large finite alphabets is very similar to coding
over the real numbers, the analysis of verification decoding
is also extended to the compressed sensing (CS) of strictly
sparse signals. A DE-based approach is used to analyze the
CS systems with randomized-reconstruction guarantees. This
leads to the result that strictly sparse signals can be
reconstructed efficiently with high probability using a
constant oversampling ratio (i.e., when the number of
measurements scales linearly with the sparsity of the
signal). A stopping-set-based approach is also used to get
stronger (e.g., uniform-in-probability) reconstruction
Doi = {10.1109/TIT.2012.2201344},
Key = {fds319351}
}

@article{fds322718,
Author = {Xia, Z and Huff, GH and Chamberland, JF and Pfister, H and Bhattacharya,
R},
Title = {Direction of arrival estimation using canonical and
crystallographic volumetric element configurations},
Journal = {Proceedings of 6th European Conference on Antennas and
Propagation, Eucap 2012},
Pages = {1436-1439},
Publisher = {IEEE},
Year = {2012},
Month = {July},
ISBN = {9781457709180},
url = {http://dx.doi.org/10.1109/EuCAP.2012.6206123},
Abstract = {Volumetric distributions of receiving antennas are
investigated for their ability to mitigate aliasing and
enhance the direction of arrival (DOA) estimation. Surface
and volumetric distributions in canonical arrangements
(cubic and spherical) of elements and configurations
inspired by crystallographic lattices (cubic, tetragonal,
etc.) are investigated using the Multiple Signal
Classification (MUSIC) algorithm. These are compared to
planar and linear distributions, and experimental
observations from basic transmission measurements are used
to evaluate several of the element distributions and compare
Doi = {10.1109/EuCAP.2012.6206123},
Key = {fds322718}
}

@article{fds319352,
Author = {Jian, Y-Y and Pfister, HD and Narayanan, KR},
Title = {Approaching capacity at high rates with iterative
hard-decision decoding.},
Journal = {Isit},
Pages = {2696-2700},
Publisher = {IEEE},
Year = {2012},
ISBN = {978-1-4673-2580-6},
url = {http://dx.doi.org/10.1109/ISIT.2012.6284009},
Doi = {10.1109/ISIT.2012.6284009},
Key = {fds319352}
}

@article{fds319353,
Author = {Hamidi-Sepehr, F and Chamberland, J-F and Pfister,
HD},
Title = {On the performance of random block codes over finite-state
Journal = {Allerton Conference},
Pages = {17-25},
Publisher = {IEEE},
Year = {2012},
ISBN = {978-1-4673-4537-8},
url = {http://dx.doi.org/10.1109/Allerton.2012.6483194},
Doi = {10.1109/Allerton.2012.6483194},
Key = {fds319353}
}

@article{fds319354,
Author = {Yedla, A and Jian, Y-Y and Nguyen, PS and Pfister,
HD},
Title = {A simple proof of threshold saturation for coupled vector
recursions.},
Journal = {Itw},
Pages = {25-29},
Publisher = {IEEE},
Year = {2012},
ISBN = {978-1-4673-0224-1},
url = {http://dx.doi.org/10.1109/ITW.2012.6404671},
Doi = {10.1109/ITW.2012.6404671},
Key = {fds319354}
}

@article{fds319355,
Author = {Yedla, A and Nguyen, PS and Pfister, HD and Narayanan,
KR},
Title = {Universal codes for the Gaussian MAC via spatial
coupling},
Journal = {2011 49th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2011},
Pages = {1801-1808},
Publisher = {IEEE},
Year = {2011},
Month = {December},
ISBN = {9781457718168},
url = {http://dx.doi.org/10.1109/Allerton.2011.6120387},
Abstract = {We consider transmission of two independent and separately
encoded sources over a two-user binary-input Gaussian
multiple-access channel. The channel gains are assumed to be
unknown at the transmitter and the goal is to design an
encoder-decoder pair that achieves reliable communication
for all channel gains where this is theoretically possible.
We call such a system universal with respect to the channel
gains. Kudekar et al. recently showed that terminated
low-density parity-check convolutional codes (a.k.a.
spatially-coupled low-density parity-check ensembles) have
belief-propagation thresholds that approach their maximum
a-posteriori thresholds. This was proven for binary erasure
channels and shown empirically for binary memoryless
symmetric channels. It was conjectured that the principle of
spatial coupling is very general and the phenomenon of
threshold saturation applies to a very broad class of
graphical models. In this work, we derive an area theorem
for the joint decoder and empirically show that threshold
saturation occurs for this problem. As a result, we
demonstrate near-universal performance for this problem
using the proposed spatially-coupled coding system. © 2011
IEEE.},
Doi = {10.1109/Allerton.2011.6120387},
Key = {fds319355}
}

@article{fds319356,
Author = {Kumar, S and Chamberland, JF and Pfister, HD},
Title = {Large deviations on empirical service for erasure channels
with memory},
Journal = {2011 49th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2011},
Pages = {1641-1648},
Publisher = {IEEE},
Year = {2011},
Month = {December},
ISBN = {9781457718168},
url = {http://dx.doi.org/10.1109/Allerton.2011.6120365},
communication link from a large deviations perspective. The
underlying physical environment is modeled as an erasure
channel with memory. Information is shielded from symbol
erasures using error-correcting codes with finite
block-lengths. At the onset of the communication process,
the transmit buffer is assumed to contain a certain number
of data bits; these bits are partitioned into segments and
subsequently transmitted as coded packets. Acknowledgments
of successful transmissions are obtained through periodic,
reliable feedback. Performance criteria are derived based on
the average service rate and the first-passage time to an
empty queue. The optimization problem is posed in an
asymptotic setting and large deviation principles are
obtained for these two quantities. The proposed analysis
framework provides a methodology tailored to code rate and
block-length selection for delay-sensitive applications.
This study leads to pertinent guidelines on how to choose
system parameters for communication over correlated
channels. Examples obtained through a numerical study are
included to further illustrate the value of the techniques
introduced in this paper. © 2011 IEEE.},
Doi = {10.1109/Allerton.2011.6120365},
Key = {fds319356}
}

@article{fds319357,
Author = {Kim, BH and Pfister, HD},
Title = {Joint decoding of LDPC codes and finite-state channels via
linear-programming},
Journal = {Ieee Journal of Selected Topics in Signal
Processing},
Volume = {5},
Number = {8},
Pages = {1563-1576},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2011},
Month = {December},
url = {http://dx.doi.org/10.1109/JSTSP.2011.2165525},
Abstract = {This paper considers the joint-decoding problem for
finite-state channels (FSCs) and low-density parity-check
(LDPC) codes. In the first part, the linear-programming (LP)
decoder for binary linear codes is extended to perform
joint-decoding of binary-input FSCs. In particular, we
provide a rigorous definition of LP joint-decoding
pseudo-codewords (JD-PCWs) that enables evaluation of the
pairwise error probability between codewords and JD-PCWs in
AWGN. This leads naturally to a provable upper bound on
decoder failure probability. If the channel is a
finite-state intersymbol interference channel, then the
joint LP decoder also has the maximum-likelihood (ML)
certificate property and all integer-valued solutions are
codewords. In this case, the performance loss relative to ML
decoding can be explained completely by fractional-valued
JD-PCWs. After deriving these results, we discovered some
elements were equivalent to earlier work by Flanagan on
linear-programming receivers. In the second part, we develop
an efficient iterative solver for the joint LP decoder
discussed in the first part. In particular, we extend the
approach of iterative approximate LP decoding, proposed by
Vontobel and Koetter and analyzed by Burshtein, to this
problem. By taking advantage of the dual-domain structure of
the joint-decoding LP, we obtain a convergent iterative
algorithm for joint LP decoding whose structure is similar
to BCJR-based turbo equalization (TE). The result is a joint
iterative decoder whose per-iteration complexity is similar
to that of TE but whose performance is similar to that of
joint LP decoding. The main advantage of this decoder is
that it appears to provide the predictability and superior
performance of joint LP decoding with the computational
complexity of TE. One expected application is coding for
magnetic storage where the required block-error rate is
extremely low and system performance is difficult to verify
Doi = {10.1109/JSTSP.2011.2165525},
Key = {fds319357}
}

@article{fds319358,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {Universality for the noisy Slepian-Wolf problem via spatial
coupling},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {2567-2571},
Publisher = {IEEE},
Year = {2011},
Month = {October},
ISBN = {9781457705953},
url = {http://dx.doi.org/10.1109/ISIT.2011.6034032},
Abstract = {We consider a noisy Slepian-Wolf problem where two
correlated sources are separately encoded and transmitted
over two independent binary memoryless symmetric channels.
Each channel capacity is assumed to be characterized by a
single parameter which is not known at the transmitter. The
receiver has knowledge of both the source correlation and
the channel parameters. We call a system universal if it
retains near-capacity performance without channel knowledge
at the transmitter. Kudekar et al. recently showed that
terminated low-density parity-check (LDPC) convolutional
codes (a.k.a. spatially-coupled LDPC ensembles) can have
belief-propagation thresholds that approach their maximum
a-posteriori thresholds. This was proven for binary erasure
channels and shown empirically for binary memoryless
symmetric channels. They also conjectured that the principle
of spatial coupling is very general and the phenomenon of
threshold saturation applies to a very broad class of
graphical models. In this work, we derive an area theorem
for the joint decoder and empirically show that threshold
saturation occurs for this problem. As a result, we
demonstrate near-universal performance for this problem
using the proposed spatially-coupled coding system. A
similar result is also discussed briefly for the 2-user
Doi = {10.1109/ISIT.2011.6034032},
Key = {fds319358}
}

@article{fds319359,
Author = {Hamidi-Sepehr, F and Cai, Y and Pfister, HD and Chamberland,
JF},
Title = {Queueing behavior of the Gilbert-Elliott channel: BCH codes
and Poisson arrivals},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {1806-1810},
Publisher = {IEEE},
Year = {2011},
Month = {October},
ISBN = {9781457705953},
url = {http://dx.doi.org/10.1109/ISIT.2011.6033861},
Abstract = {This paper considers the queueing performance of a
communication system that transmits BCH-coded data over the
correlated-error channel first studied by Gilbert and
Elliott in the 1960s. For some arrival processes, one can
join the queue length and channel state so that the pair
forms a Markov chain; this provides a powerful tool to
analyze the tail probability of the queue. For Bernoulli
packet arrivals, this approach works but does not allow for
fair comparisons between different block-length codes. In
this paper, a Poisson arrival model is assumed in order to
make fair comparisons between codes with arbitrary block
length and code rate. This enables one to optimize code
parameters for delay-sensitive communication systems over
time-varying channels. Finally, the analysis is supported
through a Monte Carlo simulation. © 2011
IEEE.},
Doi = {10.1109/ISIT.2011.6033861},
Key = {fds319359}
}

@article{fds319360,
Author = {Zhang, F and Pfister, HD},
Title = {Analysis of verification-based decoding on the q-ary
symmetric channel for large q},
Journal = {Ieee Transactions on Information Theory},
Volume = {57},
Number = {10},
Pages = {6754-6770},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2011},
Month = {October},
url = {http://dx.doi.org/10.1109/TIT.2011.2165813},
Abstract = {A new verification-based message-passing decoder for
low-density parity-check (LDPC) codes is introduced and
analyzed for the q-ary symmetric channel (q-SC). Rather than
passing messages consisting of symbol probabilities, this
decoder passes lists of possible symbols and marks some
lists as verified. The density evolution (DE) equations for
this decoder are derived and used to compute decoding
thresholds. If the maximum list size is unbounded, then one
finds that any capacity-achieving LDPC code for the binary
erasure channel can be used to achieve capacity on the q -SC
for large q. The decoding thresholds are also computed via
DE for the case where each list is truncated to satisfy a
maximum list-size constraint. Simulation results are also
presented to confirm the DE results. During the simulations,
we observed differences between two verification-based
decoding algorithms, introduced by Luby and Mitzenmacher,
that were implicitly assumed to be identical. In this paper,
the node-based algorithms are evaluated via analysis and
simulation. The probability of false verification (FV) is
also considered and techniques are discussed to mitigate the
FV. Optimization of the degree distribution is also used to
improve the threshold for a fixed maximum list size.
Finally, the proposed algorithm is compared with a variety
of other algorithms using both density evolution thresholds
and simulation results. © 2011 IEEE.},
Doi = {10.1109/TIT.2011.2165813},
Key = {fds319360}
}

@article{fds319361,
Author = {Kim, BH and Pfister, HD},
Title = {An iterative joint linear-programming decoding of LDPC codes
and finite-state channels},
Journal = {Ieee International Conference on Communications},
Publisher = {IEEE},
Year = {2011},
Month = {September},
ISBN = {9781612842332},
url = {http://dx.doi.org/10.1109/icc.2011.5962814},
Abstract = {In this paper, we introduce an efficient method for the
joint linear-programming (LP) decoding of low-density
parity-check (LDPC) codes and finite-state channels (FSCs).
In particular, we extend the approach of iterative
approximate LP decoding proposed by Vontobel and Koetter and
further analyzed by Burshtein. By taking advantage of the
dual-domain structure of the joint decoding LP, we obtain a
convergent iterative algorithm for joint decoding. Our
intent was to find an algorithm very similar to BCJR-based
turbo equalization (TE) and it seems that we have succeeded
in this respect. The result is an iterative solver for the
joint decoding LP whose complexity is similar to TE but
whose performance is similar to joint LP decoding. The main
advantage of this decoder is that it appears to provide the
predictability of joint LP decoding with the computational
complexity of TE. © 2011 IEEE.},
Doi = {10.1109/icc.2011.5962814},
Key = {fds319361}
}

@article{fds319362,
Author = {Nguyen, PS and Pfister, HD and Narayanan, KR},
Title = {On multiple decoding attempts for Reed - Solomon codes: A
rate-distortion approach},
Journal = {Ieee Transactions on Information Theory},
Volume = {57},
Number = {2},
Pages = {668-691},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2011},
Month = {February},
url = {http://dx.doi.org/10.1109/TIT.2010.2095202},
Abstract = {One popular approach to soft-decision decoding of Reed -
Solomon (RS) codes is based on using multiple trials of a
simple RS decoding algorithm in combination with erasing or
flipping a set of symbols or bits in each trial. This paper
presents a framework based on rate-distortion (RD) theory to
analyze these multiple-decoding algorithms. By defining an
appropriate distortion measure between an error pattern and
an erasure pattern, the successful decoding condition, for a
single errors-and-erasures decoding trial, becomes
equivalent to distortion being less than a fixed threshold.
Finding the best set of erasure patterns also turns into a
covering problem that can be solved asymptotically by RD
theory. Thus, the proposed approach can be used to
understand the asymptotic performance-versus-complexity
tradeoff of multiple errors-and-erasures decoding of RS
codes. This initial result is also extended a few
directions. The rate-distortion exponent (RDE) is computed
to give more precise results for moderate blocklengths.
Multiple trials of algebraic soft-decision (ASD) decoding
are analyzed using this framework. Analytical and numerical
computations of the RD and RDE functions are also presented.
Finally, simulation results show that sets of erasure
patterns designed using the proposed methods outperform
other algorithms with the same number of decoding trials. ©
2006 IEEE.},
Doi = {10.1109/TIT.2010.2095202},
Key = {fds319362}
}

@article{fds343273,
Author = {Nguyen, PS and Yedla, A and Pfister, HD and Narayanan,
KR},
Title = {Spatially-Coupled Codes and Threshold Saturation on
Intersymbol-Interference Channels},
Year = {2011},
Key = {fds343273}
}

@article{fds319364,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {Universality for the noisy Slepian-Wolf problem via spatial
coupling.},
Journal = {Isit},
Pages = {2567-2571},
Publisher = {IEEE},
Editor = {Kuleshov, A and Blinovsky, VM and Ephremides, A},
Year = {2011},
ISBN = {978-1-4577-0596-0},
url = {http://dx.doi.org/10.1109/ISIT.2011.6034032},
Doi = {10.1109/ISIT.2011.6034032},
Key = {fds319364}
}

@article{fds319365,
Author = {Yedla, A and Nguyen, PS and Pfister, HD and Narayanan,
KR},
Title = {Universal codes for the Gaussian MAC via spatial
coupling.},
Journal = {Allerton},
Pages = {1801-1808},
Publisher = {IEEE},
Year = {2011},
ISBN = {978-1-4577-1817-5},
url = {http://dx.doi.org/10.1109/Allerton.2011.6120387},
Doi = {10.1109/Allerton.2011.6120387},
Key = {fds319365}
}

@article{fds319366,
Author = {Kudekar, S and Pfister, HD},
Title = {The effect of spatial coupling on compressive
sensing},
Journal = {2010 48th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2010},
Pages = {347-353},
Publisher = {IEEE},
Year = {2010},
Month = {December},
ISBN = {9781424482146},
url = {http://dx.doi.org/10.1109/ALLERTON.2010.5706927},
Abstract = {Recently, it was observed that spatially-coupled LDPC code
ensembles approach the Shannon capacity for a class of
binary-input memoryless symmetric (BMS) channels. The
fundamental reason for this was attributed to a threshold
saturation phenomena derived in [1]. In particular, it was
shown that the belief propagation (BP) threshold of the
spatially coupled codes is equal to the maximum a posteriori
(MAP) decoding threshold of the underlying constituent
codes. In this sense, the BP threshold is saturated to its
maximum value. Moreover, it has been empirically observed
that the same phenomena also occurs when transmitting over
more general classes of BMS channels. In this paper, we show
that the effect of spatial coupling is not restricted to the
realm of channel coding. The effect of coupling also
manifests itself in compressed sensing. Specifically, we
show that spatially-coupled measurement matrices have an
improved sparsity to sampling threshold for reconstruction
algorithms based on verification decoding. For BP-based
reconstruction algorithms, this phenomenon is also tested
empirically via simulation. At the block lengths accesible
via simulation, the effect is rather small but, based on the
threshold analysis, we believe this warrants further study.
Doi = {10.1109/ALLERTON.2010.5706927},
Key = {fds319366}
}

@article{fds322719,
Author = {Chamberland, JF and Pfister, H and Shakkottai,
S},
Title = {First-passage time analysis for digital communication over
erasure channels with delay-sensitive traffic},
Journal = {2010 48th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2010},
Pages = {399-405},
Publisher = {IEEE},
Year = {2010},
Month = {December},
ISBN = {9781424482146},
url = {http://dx.doi.org/10.1109/ALLERTON.2010.5706934},
and code-rate selection for digital communication over
correlated erasure channels. The focus is on non-asymptotic
system analysis, with finite block-lengths and non-vanishing
probabilities of decoding failure. The transmit buffer is
assumed to possess a given initial distribution and
performance is evaluated in terms of the time required for
the queue to become empty. Special attention is given to
channel memory and its impact on the decoding process at the
receiver. The system is ultimately defined in terms of a
finite-state erasure channel. Using a Markov structure, the
evolution of the transmit buffer is characterized and the
distribution of the first-passage time to an empty queue is
obtained. The proposed methodology is employed to optimally
select code-rate. This provides new insights on the natural
tradeoff between error protection and data content in the
Doi = {10.1109/ALLERTON.2010.5706934},
Key = {fds322719}
}

@article{fds319367,
Author = {Kim, BH and Yedla, A and Pfister, HD},
Title = {IMP: A message-passing algorithm for matrix
completion},
Journal = {6th International Symposium on Turbo Codes and Iterative
Information Processing, Istc 2010},
Pages = {462-466},
Publisher = {IEEE},
Year = {2010},
Month = {November},
ISBN = {9781424467457},
url = {http://dx.doi.org/10.1109/ISTC.2010.5613803},
Abstract = {A new message-passing (MP) method is considered for the
matrix completion problem associated with recommender
systems. We attack the problem using a (generative) factor
graph model that is related to a probabilistic low-rank
matrix factorization. Based on the model, we propose a new
algorithm, termed IMP, for the recovery of a data matrix
from incomplete observations. The algorithm is based on a
clustering followed by inference via MP (IMP). The algorithm
is compared with a number of other matrix completion
algorithms on real collaborative filtering (e.g., Netflix)
data matrices. Our results show that, while many methods
perform similarly with a large number of revealed entries,
the IMP algorithm outperforms all others when the fraction
of observed entries is small. This is helpful because it
reduces the well-known cold-start problem associated with
collaborative filtering (CF) systems in practice. © 2010
IEEE.},
Doi = {10.1109/ISTC.2010.5613803},
Key = {fds319367}
}

@article{fds319368,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {LDPC code design for transmission of correlated sources
across noisy channels without CSIT},
Journal = {6th International Symposium on Turbo Codes and Iterative
Information Processing, Istc 2010},
Pages = {467-471},
Publisher = {IEEE},
Year = {2010},
Month = {November},
ISBN = {9781424467457},
url = {http://dx.doi.org/10.1109/ISTC.2010.5613829},
Abstract = {We consider the problem of transmitting correlated data
after independent encoding to a central receiver through
orthogonal channels. We assume that the channel state
information is not known at the transmitter. The receiver
state information. We provide a generic framework for
analyzing the performance of joint iterative decoding, using
density evolution. Using differential evolution, we design
punctured systematic LDPC codes to maximize the region of
achievable channel conditions, with joint iterative
decoding. The main contribution of this paper is to
demonstrate that properly designed LDPC can perform well
simultaneously over a wide range of channel
parameters.},
Doi = {10.1109/ISTC.2010.5613829},
Key = {fds319368}
}

@article{fds319369,
Author = {Jian, YY and Pfister, HD},
Title = {Convergence of weighted min-sum decoding via dynamic
programming on coupled trees},
Journal = {6th International Symposium on Turbo Codes and Iterative
Information Processing, Istc 2010},
Pages = {487-491},
Publisher = {IEEE},
Year = {2010},
Month = {November},
ISBN = {9781424467457},
url = {http://dx.doi.org/10.1109/ISTC.2010.5613901},
Abstract = {Applying the max-product (and belief-propagation) algorithms
to loopy graphs is now quite popular for constraint
satisfaction problems. This is largely due to their low
computational complexity and impressive performance in
practice. Still, there is no general understanding of the
conditions required for convergence and/or the optimality of
converged solutions. This paper presents an analysis of
weighted min-sum (a.k.a. attenuated max-product) decoding
for LDPC codes that guarantees convergence to a fixed point
when the weight β is sufficiently small. It also shows
that, if the fixed point satisfies all the constraints, then
it must be both the linear-programming (LP) and
maximumlikelihood (ML) solution. For (dv, dc)-regular LDPC
codes, the weight must satisfy 1/β > dv - 1 whereas the
result of Koetter and Frey requires instead that 1/β > (dv
- l)(dc - 1). A counterexample is also given that shows a
fixed point might not be the ML solution if 1/β < dv - 1.
Finally, connections are explored with recent work by Arora
et al. on the threshold of LP decoding.},
Doi = {10.1109/ISTC.2010.5613901},
Key = {fds319369}
}

@article{fds319370,
Author = {Wilson, MP and Narayanan, K and Pfister, HD and Sprintson,
A},
Title = {Joint physical layer coding and network coding for
bidirectional relaying},
Journal = {Ieee Transactions on Information Theory},
Volume = {56},
Number = {11},
Pages = {5641-5654},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2010},
Month = {November},
url = {http://dx.doi.org/10.1109/TIT.2010.2068750},
Abstract = {We consider a communication system where two transmitters
wish to exchange information through a central relay. The
transmitter and relay nodes exchange data over synchronized,
average power constrained additive white Gaussian noise
channels with a real input with signal-to-noise ratio (SNR)
of ssr. An upper bound on the capacity is 1/2 log (1+ ssr)
bits per transmitter per use of the multiple access phase
and broadcast phase of the bidirectional relay channel. We
show that, using lattice codes and lattice decoding, we can
obtain a rate of 1/2 log (1/2 + ssr) bits per transmitter,
which is essentially optimal at high SNR. The main idea is
to decode the sum of the codewords modulo a lattice at the
relay followed by a broadcast phase which performs
SlepianWolf coding. We also show that if the two
transmitters use identical lattices with minimum angle
decoding, we can achieve the same rate of 1/2 log(1/2 +
snr). The proposed scheme can be thought of as a joint
physical-layer network-layer code which outperforms other
recently proposed analog network coding schemes. © 2006
IEEE.},
Doi = {10.1109/TIT.2010.2068750},
Key = {fds319370}
}

@article{fds319371,
Author = {Nguyen, PS and Pfister, HD and Narayanan, KR},
Title = {A rate-distortion exponent approach to multiple decoding
attempts for Reed-Solomon codes},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {1095-1099},
Year = {2010},
Month = {August},
ISBN = {9781424469604},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513703},
Abstract = {Algorithms based on multiple decoding attempts of
Reed-Solomon (RS) codes have recently attracted new
attention. Choosing decoding candidates based on
rate-distortion theory, as proposed previously by the
authors, currently provides the best performance-versus-complexity
trade-off. In this paper, an analysis based on the
rate-distortion exponent is used to directly minimize the
exponential decay rate of the error probability. This
enables rigorous bounds on the error probability for
finite-length RS codes and leads to modest performance
gains. As a byproduct, a numerical method is derived that
computes the rate-distortion exponent for independent
non-identical sources. Analytical results are given for
Doi = {10.1109/ISIT.2010.5513703},
Key = {fds319371}
}

@article{fds319372,
Author = {Kim, BH and Pfister, HD},
Title = {On the joint decoding of LDPC codes and finite-state
channels via linear programming},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {754-758},
Year = {2010},
Month = {August},
ISBN = {9781424469604},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513614},
Abstract = {In this paper, the linear programming (LP) decoder for
binary linear codes, introduced by Feldman, et al. is
extended to joint-decoding of binary-input finite-state
channels. In particular, we provide a rigorous definition of
LP joint-decoding pseudo-codewords (JD-PCWs) that enables
evaluation of the pairwise error probability between
codewords and JD-PCWs. This leads naturally to a provable
upper bound on decoder failure probability. If the channel
is a finite-state intersymbol interference channel, then the
LP joint decoder also has the maximum-likelihood (ML)
certificate property and all integer valued solutions are
codewords. In this case, the performance loss relative to ML
decoding can be explained completely by fractional valued
Doi = {10.1109/ISIT.2010.5513614},
Key = {fds319372}
}

@article{fds319373,
Author = {Parag, P and Chamberland, JF and Pfister, HD and Narayanan,
KR},
Title = {On the queueing behavior of random codes over a
gilbert-elliot erasure channel},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {1798-1802},
Publisher = {IEEE},
Year = {2010},
Month = {August},
ISBN = {9781424469604},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513296},
Abstract = {This paper considers the queueing performance of a system
that transmits coded data over a time-varying erasure
channel. In our model, the queue length and channel state
together form a Markov chain that depends on the system
parameters. This gives a framework that allows a rigorous
analysis of the queue as a function of the code rate. Most
prior work in this area either ignores block-length (e.g.,
fluid models) or assumes error-free communication using
finite codes. This work enables one to determine when such
assumptions provide good, or bad, approximations of true
behavior. Moreover, it offers a new approach to optimize
parameters and evaluate performance. This can be valuable
for delay-sensitive systems that employ short block lengths.
Doi = {10.1109/ISIT.2010.5513296},
Key = {fds319373}
}

@article{fds319374,
Author = {Zhang, F and Pfister, HD and Jiang, A},
Title = {LDPC codes for rank modulation in flash memories},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {859-863},
Year = {2010},
Month = {August},
ISBN = {9781424469604},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513603},
Abstract = {An LDPC code is proposed for flash memories based on rank
modulation. In contrast to previous approaches, this enables
the use of long ECCs with fixed-length modulation codes. For
ECC design, the rank modulation scheme is treated as part of
an equivalent channel. A probabilistic model of the
equivalent channel is derived and a simple high-SNR
approximation is given. LDPC codes over integer rings and
finite fields are designed for the approximate channel and a
low-complexity symbol-flipping verification-based (SFVB)
message-passing decoding algorithm is proposed to take
advantage of the channel structure. Density evolution (DE)
is used to calculate decoding thresholds and simulations are
used to compare the low-complexity decoder with sum-product
Doi = {10.1109/ISIT.2010.5513603},
Key = {fds319374}
}

@article{fds322720,
Author = {Parag, P and Chamberland, JF and Pfister, H and Narayanan,
K},
Title = {Code rate, queueing behavior and the correlated erasure
channel},
Journal = {Ieee Information Theory Workshop 2010, Itw
2010},
Publisher = {IEEE},
Year = {2010},
Month = {July},
ISBN = {9781424463725},
url = {http://dx.doi.org/10.1109/ITWKSPS.2010.5503186},
Abstract = {This paper considers the relationship between coderate
selection and queueing performance for communication systems
with time-varying parameters. While error-correcting codes
offer protection against channel unreliability, there is a
tradeoff between the enhanced protection of low-rate codes
and the increased information transfer of high-rate codes.
Hence, there exists a natural compromise between
packet-level error protection and information rate. In the
limiting regime where codewords are asymptotically long,
this tradeoff is well-understood and characterized by the
Shannon capacity. However, for delay-sensitive communication
systems and finite code-lengths, a complete characterization
of this tradeoff is still not fully developed. This paper
offers a new perspective on the queueing performance of
communication systems with finite block-lengths operating
over correlated erasure channels. A rigorous framework that
links code rate to overall system performance for random
codes is presented. Guidelines for code rate selection in
delay-sensitive systems are identified.},
Doi = {10.1109/ITWKSPS.2010.5503186},
Key = {fds322720}
}

@article{fds343275,
Author = {Kim, B-H and Yedla, A and Pfister, HD},
Title = {Message-Passing Inference on a Factor Graph for
Collaborative Filtering},
Year = {2010},
Key = {fds343275}
}

@article{fds319375,
Author = {Kim, B-H and Pfister, HD},
Title = {An Iterative Joint Linear-Programming Decoding of LDPC Codes
and Finite-State Channels},
Volume = {abs/1009.4352},
Year = {2010},
Key = {fds319375}
}

@article{fds319376,
Author = {Kim, B-H and Pfister, HD},
Title = {On the joint decoding of LDPC codes and finite-state
channels via linear programming.},
Journal = {Isit},
Pages = {754-758},
Publisher = {IEEE},
Year = {2010},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513614},
Doi = {10.1109/ISIT.2010.5513614},
Key = {fds319376}
}

@article{fds319377,
Author = {Nguyen, PS and Pfister, HD and Narayanan, KR},
Title = {A rate-distortion exponent approach to multiple decoding
attempts for Reed-Solomon codes.},
Journal = {Isit},
Pages = {1095-1099},
Publisher = {IEEE},
Year = {2010},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513703},
Doi = {10.1109/ISIT.2010.5513703},
Key = {fds319377}
}

@article{fds319378,
Author = {Parag, P and Chamberland, J-F and Pfister, HD and Narayanan,
KR},
Title = {On the queueing behavior of random codes over a
gilbert-elliot erasure channel.},
Journal = {Isit},
Pages = {1798-1802},
Publisher = {IEEE},
Year = {2010},
url = {http://dx.doi.org/10.1109/ISIT.2010.5513296},
Doi = {10.1109/ISIT.2010.5513296},
Key = {fds319378}
}

@article{fds319379,
Author = {Nguyen, PS and Pfister, HD and Narayanan, KR},
Title = {On Multiple Decoding Attempts for Reed-Solomon
Codes},
Volume = {abs/1005.4461},
Year = {2010},
Key = {fds319379}
}

@article{fds343274,
Author = {Pfister, HD},
Title = {The Capacity of Finite-State Channels in the High-Noise
Regime},
Year = {2010},
Key = {fds343274}
}

@article{fds319383,
Author = {Zhang, F and Pfister, HD},
Title = {Modulation codes for flash memory based on load-balancing
theory},
Journal = {2009 47th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2009},
Pages = {1039-1046},
Publisher = {IEEE},
Year = {2009},
Month = {December},
ISBN = {9781424458714},
url = {http://dx.doi.org/10.1109/ALLERTON.2009.5394880},
Abstract = {In this paper, we consider modulation codes for practical
multilevel flash memory storage systems with q cell levels.
[2], [4], we maximize the average amount of information
stored per cell-level, which is defined as storage
efficiency. Using this framework, we show that the
worst-case criterion [7], [1], [2] and the average-case
criterion [4] are two extreme cases of our objective
function. A self-randomized modulation code is proposed
which is asymptotically optimal, as q → ∞, for an
arbitrary input alphabet and i.i.d. input distribution. In
practical flash memory systems, the number of cell-levels q
is only moderately large. So the asymptotic performance as q
→ ∞ may not tell the whole story. Using the tools from
load-balancing theory, we analyze the storage efficiency of
the self-randomized modulation code. The result shows that
only a fraction of the cells are utilized when the number of
cell-levels q is only moderately large. We also propose a
load-balancing modulation code, based on a phenomenon known
as "the power of two random choices" [10], to improve the
storage efficiency of practical systems. Theoretical
analysis and simulation results show that our load-balancing
modulation codes can provide significant gain to practical
flash memory storage systems. Though pseudo-random, our
approach achieves the same load-balancing performance, for
i.i.d. inputs, as a purely random approach based on the
power of two random choices. ©2009 IEEE.},
Doi = {10.1109/ALLERTON.2009.5394880},
Key = {fds319383}
}

@article{fds319384,
Author = {Maduike, D and Pfister, HD and Sprintson, A},
Title = {Design and implementation of physical-layer network-coding
protocols},
Journal = {Conference Record Asilomar Conference on Signals, Systems
and Computers},
Pages = {781-787},
Publisher = {IEEE},
Year = {2009},
Month = {December},
ISBN = {9781424458271},
url = {http://dx.doi.org/10.1109/ACSSC.2009.5469964},
Abstract = {Recently, there has been a growing interest in
physical-layer network-coding techniques that facilitate
information transfer in wireless relay networks.
Physical-layer networkcoding techniques take advantage of
the additive nature of wireless signals by allowing two
terminals to transmit simultaneously to the relay node. This
technique has several performance benefits, such as
improving utilization and throughput of wireless channels
and reducing delay. In this paper, we present an algorithm
for joint decoding of two unsynchronized transmitters to the
modulo-2 sum of their transmitted messages. We address the
problems that arise when the boundaries of the signals do
not align with each other and when their phases are not
identical. Our approach uses a statebased Viterbi decoding
scheme that takes into account the timing offsets between
the interfering signals. Our simulation studies show that
this decoder outperforms previous approaches in the presence
of noise and timing offset. © 2009 IEEE.},
Doi = {10.1109/ACSSC.2009.5469964},
Key = {fds319384}
}

@article{fds319381,
Author = {Nguyen, PS and Pfister, HD and Narayanan, KR},
Title = {A rate-distortion perspective on multiple decoding attempts
for Reed-Solomon codes},
Journal = {2009 47th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2009},
Pages = {1235-1242},
Year = {2009},
Month = {December},
ISBN = {9781424458714},
url = {http://dx.doi.org/10.1109/ALLERTON.2009.5394533},
Abstract = {Recently, a number of authors have proposed decoding schemes
for Reed-Solomon (RS) codes based on multiple trials of a
simple RS decoding algorithm. In this paper, we present a
rate-distortion (R-D) approach to analyze these
multiple-decoding algorithms for RS codes. This approach is
first used to understand the asymptotic performance-versus-complexity
trade-off of multiple error-and-erasure decoding of RS
codes. By defining an appropriate distortion measure between
an error pattern and an erasure pattern, the condition for a
single error-and-erasure decoding to succeed reduces to a
form where the distortion is compared to a fixed threshold.
Finding the best set of erasure patterns for multiple
decoding trials then turns out to be a covering problem
which can be solved asymptotically by rate-distortion
theory. Next, this approach is extended to analyze multiple
algebraic soft-decision (ASD) decoding of RS codes. Both
analytical and numerical computations of the R-D functions
for the corresponding distortion measures are discussed.
Simulation results show that proposed algorithms using this
approach perform better than other algorithms with the same
Doi = {10.1109/ALLERTON.2009.5394533},
Key = {fds319381}
}

@article{fds319382,
Author = {Yedla, A and Pfister, HD and Narayanan, KR},
Title = {Can iterative decoding for erasure correlated sources be
universal?},
Journal = {2009 47th Annual Allerton Conference on Communication,
Control, and Computing, Allerton 2009},
Pages = {408-415},
Publisher = {IEEE},
Year = {2009},
Month = {December},
ISBN = {9781424458714},
url = {http://dx.doi.org/10.1109/ALLERTON.2009.5394794},
Abstract = {In this paper, we consider a few iterative decoding schemes
for the joint source-channel coding of correlated sources.
Specifically, we consider the joint source-channel coding of
two erasure correlated sources with transmission over
different erasure channels. Our main interest is in
determining whether or not various code ensembles can
achieve the capacity region universally over varying channel
conditions. We consider two ensembles in the class of
low-density generator-matrix (LDGM) codes known as
Luby-Transform (LT) codes and one ensemble of low-density
parity-check (LDPC) codes.We analyze them using density
evolution and show that optimized LT codes can achieve the
extremal symmetric point of the capacity region. We also
show that LT codes are not universal under iterative
decoding for this problem because they cannot simultaneously
achieve the extremal symmetric point and a corner point of
the capacity region. The sub-universality of iterative
decoding is characterized by studying the density evolution
Doi = {10.1109/ALLERTON.2009.5394794},
Key = {fds319382}
}

@article{fds343276,
Author = {Zhang, F and Pfister, HD},
Title = {On the Iterative Decoding of High-Rate LDPC Codes With
Applications in Compressed Sensing},
Year = {2009},
Key = {fds343276}
}

@article{fds319385,
Author = {Wang, C and Pfister, HD},
Title = {Upper bounds on the MAP threshold of iterative decoding
systems with erasure noise},
Journal = {2008 5th International Symposium on Turbo Codes and Related
Topics, Turbocoding},
Pages = {7-12},
Publisher = {IEEE},
Year = {2008},
Month = {December},
ISBN = {9781424428632},
url = {http://dx.doi.org/10.1109/TURBOCODING.2008.4658664},
Abstract = {Following the work of Méasson, Montanari, and Urbanke, this
paper considers the maximum a posteriori (MAP) decoding
thresholds of three iterative decoding systems. First,
irregular repeat-accumulate (IRA) and accumulate-repeat-accumulate
(ARA) code ensembles are analyzed on the binary erasure
channel (BEC). Next, the joint iterative decoding of LDPC
codes is studied on the dicode erasure channel (DEC). The
DEC is a two-state intersymbol-interference (ISI) channel
with erasure noise, and it is the simplest example of an ISI
channel with erasure noise. The MAP threshold bound for the
joint decoder is based on a slight generalization of the
EXIT area theorem. © 2008 IEEE.},
Doi = {10.1109/TURBOCODING.2008.4658664},
Key = {fds319385}
}

@article{fds319386,
Author = {Zhang, F and Pfister, HD},
Title = {Compressed sensing and linear codes over real
numbers},
Journal = {2008 Information Theory and Applications Workshop Conference
Proceedings, Ita},
Pages = {558-561},
Publisher = {IEEE},
Year = {2008},
Month = {October},
ISBN = {1424426707},
url = {http://dx.doi.org/10.1109/ITA.2008.4601055},
Abstract = {Compressed sensing (CS) is a relatively new area of signal
processing and statistics that focuses on signal
reconstruction from a small number of linear (e.g., dot
product) measurements. In this paper, we analyze CS using
tools from coding theory because CS can also be viewed as
syndrome-based source coding of sparse vectors using linear
codes over real numbers. While coding theory does not
typically deal with codes over real numbers, there is
actually a very close relationship between CS and
error-correcting codes over large discrete alphabets. This
connection leads naturally to new reconstruction methods and
analysis. In some cases, the resulting methods provably
require many fewer measurements than previous
approaches.},
Doi = {10.1109/ITA.2008.4601055},
Key = {fds319386}
}

@article{fds319387,
Author = {Zhang, F and Mao, X and Zhou, W and Pfister, HD},
Title = {Girth-10 LDPC codes based on 3-D cyclic lattices},
Journal = {Ieee Transactions on Vehicular Technology},
Volume = {57},
Number = {2},
Pages = {1049-1060},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2008},
Month = {March},
url = {http://dx.doi.org/10.1109/TVT.2007.905622},
Abstract = {In this paper, we propose a new method based on
combinatorial designs for constructing high-girth
low-density parity-check (LDPC) codes. We use a 3-D lattice
to generate balanced incomplete block designs based on
planes and lines in the lattice. This gives families of
regular LDPC codes with girths of at least 6, 8, and 10,
whose parity-check matrices are all block circulant. The
main advantage of this construction is that the algebraic
structure leads to efficient encoders and decoders. Based on
the block-circulant structure of a parity-check matrix, we
present an efficient encoder that can be parallelized to
improve the speed of encoding. The simulation results show
that these families of LDPC codes perform very well on
additive-white-Gaussian-noise channels (roughly 0.45 dB from
the channel capacity) and Rayleigh fading channels (roughly
0.51 dB from the channel capacity). © 2008
IEEE.},
Doi = {10.1109/TVT.2007.905622},
Key = {fds319387}
}

@article{fds319389,
Author = {Pfister, HD and Siegel, PH},
Title = {Joint iterative decoding of LDPC codes for channels with
memory and erasure noise},
Journal = {Ieee Journal on Selected Areas in Communications},
Volume = {26},
Number = {2},
Pages = {320-337},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2008},
Month = {February},
url = {http://dx.doi.org/10.1109/JSAC.2008.080209},
Abstract = {This paper investigates the joint iterative decoding of
low-density parity-check (LDPC) codes and channels with
memory. Sequences of irregular LDPC codes are presented that
achieve, under joint iterative decoding, the symmetric
information rate of a class of channels with memory and
erasure noise. This gives proof, for the first time, that
joint iterative decoding can be information rate lossless
with respect to maximum-likelihood decoding. These results
build on previous capacity-achieving code constructions for
the binary erasure channel. A two state intersymbol-interference
channel with erasure noise, known as the dicode erasure
channel, is used as a concrete example throughout the paper.
Doi = {10.1109/JSAC.2008.080209},
Key = {fds319389}
}

@article{fds319388,
Author = {Zhang, F and Pfister, HD},
Title = {Compressed Sensing and Linear Codes over Real
Numbers},
Journal = {2008 Information Theory and Applications
Workshop},
Pages = {278-281},
Publisher = {IEEE},
Year = {2008},
Month = {January},
ISBN = {978-1-4244-2670-6},
Key = {fds319388}
}

@article{fds319390,
Author = {Fan, Z and Pfister, HD},
Title = {List-message passing achieves capacity on the q-ary
symmetric channel for large q},
Journal = {Globecom Ieee Global Telecommunications Conference},
Pages = {283-287},
Publisher = {IEEE},
Year = {2007},
Month = {December},
ISBN = {1424410436},
url = {http://dx.doi.org/10.1109/GLOCOM.2007.60},
Abstract = {We discuss and analyze a list-message-passing decoder with
verification for low-density parity-check (LDPC) codes on
the q-ary symmetric channel (q-SC). Rather than passing
messages consisting of symbol probabilities, we pass lists
of possible symbols and mark very likely symbols as
verified. The density evolution (DE) equations for this
decoder are derived and used to compute decoding thresholds.
If the maximum list-size is unbounded, then we find that any
capacity-achieving LDPC code for the binary erasure channel
can be used to achieve capacity on the q-SC for large q. The
decoding thresholds are also computed via DE for the case
where each list is truncated to satisfy a maximum list-size
constraint. The probability of false verification is
considered for this case, and techniques are discussed to
mitigate the problem. Optimization of the degree
distribution is also used to improve the threshold for a
fixed maximum list size. Finally, the proposed algorithm is
compared with a variety of other algorithms using both
density evolution thresholds and simulation results. © 2007
IEEE.},
Doi = {10.1109/GLOCOM.2007.60},
Key = {fds319390}
}

@article{fds319391,
Author = {Diggavi, S and Mitzenmacher, M and Pfister, HD},
Title = {Capacity upper bounds for the deletion channel},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {1716-1720},
Publisher = {IEEE},
Year = {2007},
Month = {December},
ISBN = {1424414296},
url = {http://dx.doi.org/10.1109/ISIT.2007.4557469},
Abstract = {We present two upper bounds on the capacity of the i.i.d.
binary deletion channel, where each bit is independently
deleted with a fixed probability d. The first can be
numerically evaluated for any fixed d. The second provides
an asymptotic upper bound as d goes to 1. These appeal to be
the fiist non-trivial upper bounds for this probabilistic
Doi = {10.1109/ISIT.2007.4557469},
Key = {fds319391}
}

@article{fds319392,
Author = {Pfister, HD and Sason, I},
Title = {Accumulate-repeat-accumulate codes: Capacity-achieving
ensembles of systematic codes for the erasure channel with
bounded complexity},
Journal = {Ieee Transactions on Information Theory},
Volume = {53},
Number = {6},
Pages = {2088-2115},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2007},
Month = {June},
url = {http://dx.doi.org/10.1109/TIT.2007.896873},
Abstract = {This paper introduces ensembles of systematic
accumulaterepeataccumulate (ARA) codes which asymptotically
achieve capacity on the binary erasure channel (BEC) with
bounded complexity, per information bit, of encoding and
decoding. It also introduces symmetry properties which play
a central role in the construction of new capacity-achieving
ensembles for the BEC. The results here improve on the
tradeoff between performance and complexity provided by
previous constructions of capacity-achieving code ensembles
defined on graphs. The superiority of ARA codes with
moderate to large block length is exemplified by computer
simulations which compare their performance with those of
previously reported capacity-achieving ensembles of
low-density parity-check (LDPC) and irregular
repeataccumulate (IRA) codes. ARA codes also have the
Doi = {10.1109/TIT.2007.896873},
Key = {fds319392}
}

@article{fds319393,
Author = {Soriaga, JB and Pfister, HD and Siegel, PH},
Title = {Determining and approaching achievable rates of binary
intersymbol interference channels using multistage
decoding},
Journal = {Ieee Transactions on Information Theory},
Volume = {53},
Number = {4},
Pages = {1416-1429},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2007},
Month = {April},
url = {http://dx.doi.org/10.1109/TIT.2007.892778},
Abstract = {By examining the achievable rates of a multistage decoding
system on stationary ergodic channels, we derive lower
bounds on the mutual information rate corresponding to
independent and uniformly distributed (i.u.d.) inputs, also
referred to as the i.u.d. information rate. For binary
intersymbol interference (ISI) channels, we show that these
bounds become tight as the number of decoding stages
increases. Our analysis, which focuses on the marginal
conditional output densities at each stage of decoding,
provides an information rate corresponding to each stage.
These rates underlie the design of multilevel coding
schemes, based upon low-density parity-check (LDPC) codes
and message passing, that in combination with multistage
decoding approach the i.u.d. information rate for binary ISI
channels. We give example constructions for channel models
that have been commonly used in magnetic recording. These
examples demonstrate that the technique is very effective
even for a small number of decoding stages. © 2007
IEEE.},
Doi = {10.1109/TIT.2007.892778},
Key = {fds319393}
}

@article{fds319394,
Author = {Zhang, F and Pfister, HD},
Title = {List-Message Passing Achieves Capacity on the q-ary
Symmetric Channel for Large q.},
Journal = {Globecom},
Pages = {283-287},
Publisher = {IEEE},
Year = {2007},
url = {http://dx.doi.org/10.1109/GLOCOM.2007.60},
Doi = {10.1109/GLOCOM.2007.60},
Key = {fds319394}
}

@article{fds319395,
Author = {Hou, J and Smee, JE and Soriaga, JB and Chen, J and Pfister,
HD},
Title = {Link-level modeling and performance of CDMA interference
cancellation},
Journal = {Globecom Ieee Global Telecommunications Conference},
Publisher = {IEEE},
Year = {2006},
Month = {December},
ISBN = {142440357X},
url = {http://dx.doi.org/10.1109/GLOCOM.2006.661},
Abstract = {A general framework is provided to characterize the link
level performance of CDMA systems with interference
cancellation. This closed-form residual power analysis
accounts for the impact of channel estimation errors due to
SNR, channel variation, chip asynchronism, and filter
mismatch. Simulations further quantify the link level
cancellation performance on more realistic sub-chip
multipath channels. This work demonstrates that properly
designed channel estimation and signal reconstruction
techniques achieve high cancellation efficiency over a
IEEE.},
Doi = {10.1109/GLOCOM.2006.661},
Key = {fds319395}
}

@article{fds319396,
Author = {Sason, I and Pfister, HD},
Title = {Recent results on capacity-achieving codes for the erasure
channel with bounded complexity},
Journal = {Ieee Convention of Electrical and Electronics Engineers in
Israel, Proceedings},
Pages = {339-343},
Publisher = {IEEE},
Year = {2006},
Month = {December},
ISBN = {1424402301},
url = {http://dx.doi.org/10.1109/EEEI.2006.321096},
Abstract = {The paper introduces ensembles of accumulate-repeat-accumulate
(ARA) codes which asymptotically achieve capacity on the
binary erasure channel (BEC) with bounded complexity (per
information bit). It also introduces symmetry properties
which play a central role in the construction of various
capacity-achieving ensembles for the BEC. The results
improve on the tradeoff between performance and complexity
provided by the first capacity-achieving ensembles of
irregular repeat-accumulate (IRA) codes with bounded
complexity (constructed by Pfister, Sason and Urbanke). The
superiority of ARA codes with moderate to large block
lengths is exemplified by computer simulations comparing
their performance with those of previously reported
capacity-achieving ensembles of LDPC and IRA codes. ARA
IEEE.},
Doi = {10.1109/EEEI.2006.321096},
Key = {fds319396}
}

@article{fds319397,
Author = {Hou, J and Smee, JE and Pfister, HD and Tomasin, S},
Title = {Implementing interference cancellation to increase the EV-DO
Journal = {Ieee Communications Magazine},
Volume = {44},
Number = {2},
Pages = {96-102},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2006},
Month = {February},
url = {http://dx.doi.org/10.1109/MCOM.2006.1593551},
interference cancellation can be implemented on the EV-DO
Rev A reverse link. It is shown that applying interference
cancellation to CDMA achieves the multiple access channel
sum rate capacity for either frame synchronous or
asynchronous users. The per user SINR gain from space-time
interference cancellation translates directly into a CDMA
capacity gain of the same factor, allowing EV-DO Rev A to
support more users with higher data rates. We demonstrate
how interference cancellation can be added to base station
processing without modifying user terminals, EV-DO
standards, or network coverage. We present commercially
viable receiver architectures for implementing interference
cancellation with the asynchronism and H-ARQ of EV-DO RevA,
and explain why closed loop power control can operate the
same way it does today. Network level simulations over a
wide range of channels confirm that interference
cancellation offers significant capacity gains for all
users, while maintaining the same link budget and system
Doi = {10.1109/MCOM.2006.1593551},
Key = {fds319397}
}

@article{fds319398,
Author = {Sason, I and Pfister, HD},
Title = {Recent results on capacity-achieving codes for the erasure
channel with bounded complexity},
Journal = {2006 Ieee 24th Convention of Electrical & Electronics
Engineers in Israel},
Pages = {343-+},
Publisher = {IEEE},
Year = {2006},
Month = {January},
ISBN = {978-1-4244-0229-8},
Key = {fds319398}
}

@article{fds319399,
Author = {Pfister, HD},
Title = {Finite-length analysis of a capacity-achieving ensemble for
the binary erasure channel},
Journal = {Proceedings of the Ieee Itsoc Information Theory Workshop
2005 on Coding and Complexity, Itw2005},
Pages = {166-170},
Publisher = {IEEE},
Year = {2005},
Month = {December},
ISBN = {078039481X},
url = {http://dx.doi.org/10.1109/ITW.2005.1531880},
Abstract = {In this paper, we consider the finite-length performance of
a capacity-achieving sequence of irregular repeat-accumulate
(IRA) code ensembles. We focus on a sequence of bit-regular
ensembles with degree 3 which was shown to achieve capacity
with bounded complexity [9]. To characterize how fast the
block length of the code must grow with respect to the
truncation point of the degree distribution (i.e., maximum
check degree), we compute an upper bound on the average
weight enumerator. Based on this analysis, we present a
particular truncation sequence that could achieve a minimum
distance which grows like n1/3 even as the gap to capacity
goes to zero. We also consider the performance of these
codes in the waterfall region by extending the finite-length
scaling law [1] from low-density parity-check codes to IRA
codes. This shows that the performance near the iterative
decoding threshold is well characterized by a suitably
scaled Q-function for large enough block length. Numerical
results are given for the scaling parameters of this
ensemble sequence and for a few other IRA codes.
Unfortunately, the simulation results for the
capacity-achieving sequence start to match the scaling law
only for very large block lengths. © 2005
IEEE.},
Doi = {10.1109/ITW.2005.1531880},
Key = {fds319399}
}

@article{fds319400,
Author = {Pfister, HD and Sason, I and Urbanke, R},
Title = {Capacity-achieving ensembles for the binary erasure channel
with bounded complexity},
Journal = {Ieee Transactions on Information Theory},
Volume = {51},
Number = {7},
Pages = {2352-2379},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2005},
Month = {July},
url = {http://dx.doi.org/10.1109/TIT.2005.850079},
Abstract = {We present two sequences of ensembles of non-systematic
irregular repeat-accumulate (IRA) codes which asymptotically
(as their block length tends to infinity) achieve capacity
on the binary erasure channel (BEC) with bounded complexity
per information bit. This is in contrast to all previous
constructions of capacity-achieving sequences of ensembles
whose complexity grows at least like the log of the inverse
of the gap (in rate) to capacity. The new bounded complexity
result is achieved by puncturing bits, and allowing in this
way a sufficient number of state nodes in the Tanner graph
representing the codes. We derive an information-theoretic
lower bound on the decoding complexity of randomly punctured
codes on graphs. The bound holds for every memoryless
binary-input output-symmetric (MBIOS) channel and is refined
for the binary erasure channel. © 2005 IEEE.},
Doi = {10.1109/TIT.2005.850079},
Key = {fds319400}
}

@article{fds319401,
Author = {Pfister, HD and Sason, I},
Title = {Accumulate-repeat-accumulate codes: Systematic codes
achieving the binary erasure channel capacity with bounded
complexity},
Journal = {43rd Annual Allerton Conference on Communication, Control
and Computing 2005},
Volume = {1},
Pages = {30-44},
Year = {2005},
Month = {January},
ISBN = {9781604234916},
Abstract = {The paper introduces ensembles of accumulate-repeat-accumulate
(ARA) codes which asymptotically achieve capacity on the
binary erasure channel (BEC) with bounded complexity per
information bit. It also introduces symmetry properties
which play a central role in the construction of
capacity-achieving ensembles for the BEC. The results here
improve on the tradeoff between performance and complexity
provided by the first capacity-achieving ensembles of
irregular repeat-accumulate (IRA) codes with bounded
complexity per information bit; these IRA ensembles were
previously constructed by Pfister, Sason and Urbanke. The
superiority of ARA codes with moderate to large block length
is exemplified by computer simulations which compare their
performance with those of previously reported
capacity-achieving ensembles of LDPC and IRA codes. The ARA
codes also have the advantage of being systematic.},
Key = {fds319401}
}

@article{fds319402,
Author = {Pfister, HD and Sason, I},
Title = {Capacity-Achieving Ensembles of Accumulate-Repeat-Accumulate
Codes for the Erasure Channel with Bounded
Complexity},
Volume = {abs/cs/0512006},
Year = {2005},
Key = {fds319402}
}

@article{fds319403,
Author = {Pfister, HD and Sason, I and Urbanke, RL},
Title = {Capacity-achieving ensembles for the binary erasure channel
with bounded complexity.},
Journal = {Ieee Trans. Information Theory},
Volume = {51},
Pages = {2352-2379},
Year = {2005},
url = {http://dx.doi.org/10.1109/TIT.2005.850079},
Doi = {10.1109/TIT.2005.850079},
Key = {fds319403}
}

@article{fds322721,
Author = {Pfister, H and Sason, I and Urbanke, R},
Title = {Capacity-achieving ensembles for the binary erasure channel
with bounded complexity},
Journal = {Ieee Convention of Electrical and Electronics Engineers in
Israel, Proceedings},
Pages = {110-113},
Publisher = {IEEE},
Year = {2004},
Month = {December},
ISBN = {078038427X},
url = {http://dx.doi.org/10.1109/eeei.2004.1361101},
Abstract = {We present two sequences of ensembles of non-systematic
irregular repeat-accumulate codes which asymptotically (as
their block length tends to infinity) achieve capacity on
the binary erasure channel (BEC) with bounded complexity.
This is in contrast to all previous constructions of
capacity-achieving sequences of ensembles whose complexity
grows at least like the log of the inverse of the gap to
capacity. The new bounded complexity result is achieved by
allowing a sufficient number of state nodes in the Tanner
graph representing the codes. ©2004 IEEE.},
Doi = {10.1109/eeei.2004.1361101},
Key = {fds322721}
}

@article{fds322722,
Author = {Pfister, H and Sason, I and Urbanke, R},
Title = {Capacity-achieving ensembles for the binary erasure channel
with bounded complexity},
Journal = {Ieee International Symposium on Information Theory
Proceedings},
Pages = {207},
Year = {2004},
Month = {October},
Abstract = {We present two sequences of ensembles of non-systematic
irregular repeat-accumulate codes which asymptotically (as
their block length tends to infinity) achieve capacity on
the binary erasure channel (BEC) with bounded complexity.
This is in contrast to all previous constructions of
capacity-achieving sequences of ensembles whose complexity
grows at least like the log of the inverse of the gap to
capacity. The new bounded complexity result is achieved by
allowing a sufficient number of state nodes in the Tanner
graph representing the codes.},
Key = {fds322722}
}

@article{fds343277,
Author = {Pfister, HD and Sason, I and Urbanke, RL},
Title = {Bounds on the decoding complexity of punctured codes on
graphs},
Year = {2004},
Key = {fds343277}
}

@article{fds319404,
Author = {Soriaga, JB and Pfister, HD and Siegel, PH},
Title = {On the low-rate shannon limit for binary intersymbol
interference channels},
Journal = {Ieee Transactions on Communications},
Volume = {51},
Number = {12},
Pages = {1962-1964},
Year = {2003},
Month = {December},
url = {http://dx.doi.org/10.1109/TCOMM.2003.820724},
Abstract = {For a discrete-time, binary-input Gaussian channel with
finite intersymbol interference, we prove that reliable
communication can be achieved if and only if Eb/No > log
2/Gopt, for some constant Gopt that depends on the channel.
To determine this constant, we consider the finite-state
machine which represents the output sequences of the channel
filter when driven by binary inputs. We then define Gopt as
the maximum output power achieved by a simple cycle in this
graph, and show that no other cycle or asymptotically long
sequence can achieve an output power greater than this. We
provide examples where the binary input constraint leads to
a suboptimality, and other cases where binary signaling is
just as effective as real signaling at very low
signal-to-noise ratios.},
Doi = {10.1109/TCOMM.2003.820724},
Key = {fds319404}
}

@article{fds319405,
Author = {Hou, J and Siegel, PH and Milstein, LB and Pfister,
HD},
Title = {Capacity-Approaching Bandwidth-Efficient Coded Modulation
Schemes Based on Low-Density Parity-Check
Codes},
Journal = {Ieee Transactions on Information Theory},
Volume = {49},
Number = {9},
Pages = {2141-2155+2322},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2003},
Month = {September},
url = {http://dx.doi.org/10.1109/TIT.2003.815777},
Abstract = {We design multilevel coding (MLC) and bit-interleaved coded
modulation (BICM) schemes based on low-density parity-check
(LDPC) codes. The analysis and optimization of the LDPC
component codes for the MLC and BICM schemes are complicated
because, in general, the equivalent binary-input component
channels are not necessarily symmetric. To overcome this
obstacle, we deploy two different approaches: one based on
independent and identically distributed (i.i.d.) channel
adapters and the other based on coset codes. By
incorporating i.i.d. channel adapters, we can force the
symmetry of each binary-input component channel. By
considering coset codes, we extend the concentration theorem
based on previous work by Richardson et al. and Kavčić et
al. We also discuss the relation between the systems based
on the two approaches and show that they indeed have the
same expected decoder behavior. Next, we jointly optimize
the code rates and degree distribution pairs of the LDPC
component codes for the MLC scheme. The optimized irregular
LDPC codes at each level of MLC with multistage decoding
(MSD) are able to perform well at signal-to-noise ratios
(SNR) very close to the capacity of the additive white
Gaussian noise (AWGN) channel. We also show that the
optimized BICM scheme can approach the parallel independent
decoding (PID) capacity as closely as does the MLC/PID
scheme. Simulations with very large codeword length verify
the accuracy of the analytical results. Finally, we compare
the simulated performance of these coded modulation schemes
at finite codeword lengths, and consider the results from
the perspective of a random coding exponent
analysis.},
Doi = {10.1109/TIT.2003.815777},
Key = {fds319405}
}

@article{fds319406,
Author = {Pfister, HD and Siegel, PH},
Title = {The serial concatenation of rate-1 codes through uniform
random interleaves},
Journal = {Ieee Transactions on Information Theory},
Volume = {49},
Number = {6},
Pages = {1425-1438},
Publisher = {Institute of Electrical and Electronics Engineers
(IEEE)},
Year = {2003},
Month = {June},
url = {http://dx.doi.org/10.1109/TIT.2003.811907},
Abstract = {Until the analysis of Repeat Accumulate codes by Divsalar et
al., few people would have guessed that simple rate-1 codes
could play a crucial role in the construction of "good"
binary codes. In this paper, we will construct "good" binary
linear block codes at any rate r < 1 by serially
concatenating an arbitrary outer code of rate r with a large
number of rate-1 inner codes through uniform random
interleavers. We derive the average output weight enumerator
(WE) for this ensemble in the limit as the number of inner
codes goes to infinity. Using a probabilistic upper bound on
the minimum distance, we prove that long codes from this
ensemble will achieve the Gilbert-Varshamov bound with high
probability. Numerical evaluation of the minimum distance
shows that the asymptotic bound can be achieved with a small
number of inner codes. In essence, this construction
produces codes with good distance properties which are also
compatible with iterative "turbo" style decoding. For
selected codes, we also present bounds on the probability of
maximum-likelihood decoding (MLD) error and simulation
results for the probability of iterative decoding
error.},
Doi = {10.1109/TIT.2003.811907},
Key = {fds319406}
}

@article{fds319407,
Author = {Askar, NK and Lin, SC and Pfister, HD and Rogerson, GE and Furuno,
DS},
Title = {Spectral keying/spl trade/: A novel modulation scheme for
UWB systems},
Journal = {2003 Ieee Conference on Ultra Wideband Systems and
Technologies, Uwbst 2003 Conference Proceedings},
Pages = {418-422},
Publisher = {IEEE},
Year = {2003},
Month = {January},
ISBN = {0780381874},
url = {http://dx.doi.org/10.1109/UWBST.2003.1267876},
Abstract = {Spectral keying (SK) is a novel UWB modulation scheme that
combines properties of both frequency shift keying and pulse
position modulation. An SK symbol consists of a number of
pulses where each pulse is from a different frequency band.
It relies on dividing the available spectrum into multiple
bands. The information is encoded by the sequence of the
sent bands. It is found that the SK available symbol set
scales factorially with the number of frequency bands in
use. Theoretical analysis and simulations of a five band SK
system are provided. Measurement results from an
experimental SK system are also included. © 2003
IEEE.},
Doi = {10.1109/UWBST.2003.1267876},
Key = {fds319407}
}

@article{fds319408,
Author = {Soriaga, JB and Pfister, HD and Siegel, PH},
Title = {On the low-rate Shannon limit for binary intersymbol
interference channels.},
Journal = {Ieee Trans. Communications},
Volume = {51},
Pages = {1962-1964},
Year = {2003},
url = {http://dx.doi.org/10.1109/TCOMM.2003.820724},
Doi = {10.1109/TCOMM.2003.820724},
Key = {fds319408}
}

@article{fds319409,
Author = {Soriaga, JB and Pfister, HD and Siegel, PH},
Title = {On approaching the capacity of finite-state intersymbol
interference channels},
Journal = {Information, Coding and Mathematics},
Volume = {687},
Pages = {365-378},
Editor = {Blaum, M and Farrell, PG and VanTilborg, HCA},
Year = {2002},
Month = {January},
ISBN = {1-4020-7079-9},
Key = {fds319409}
}

@article{fds319410,
Author = {Hou, J and Siegel, PH and Milstein, LB and Pfister,
HD},
Title = {Multilevel coding with low-density parity-check component
codes},
Journal = {Conference Record / Ieee Global Telecommunications
Conference},
Volume = {2},
Pages = {1016-1020},
Year = {2001},
Month = {December},
Abstract = {We design multilevel coding (MLC) schemes with low-density
parity-check (LDPC) codes as component codes at each level.
We develop a method to analyze the performance of an LDPC
code at any level as the codeword length goes to infinity
even if the equivalent binary, input component channels are
not symmetric. By joint optimization of code rates and
degree distributions, the optimized irregular LDPC codes at
each level are capable of achieving reliable transmission at
signal-to-noise ratios (SNR) very close to the capacity of
the additive white Gaussian noise (AWGN) channel as the
codeword length tends to infinity. Simulation results show
that the optimized LDPC codes also perform very well at
moderate code-word lengths.},
Key = {fds319410}
}

@article{fds319411,
Author = {Pfister, HD and Soriaga, JB and Siegel, PH},
Title = {On the achievable information rates of finite state ISI
channels},
Journal = {Conference Record / Ieee Global Telecommunications
Conference},
Volume = {5},
Pages = {2992-2996},
Year = {2001},
Month = {December},
Abstract = {In this paper, we present two simple Monte Carlo methods for
estimating the achievable information rates of general
finite state channels. Both methods require only the ability
to simulate the channel with an a posteriori probability
(APP) detector matched to the channel. The first method
estimates the mutual information rate between the input
random process and the output random process, provided that
both processes are stationary and ergodic. When the inputs
are i.i.d, equiprobable, this rate is known as the Symmetric
Information Rate (SIR). The second method estimates the
achievable information rate of an explicit coding system
which interleaves m independent codes onto the channel and
employs multistage decoding. For practical values of m,
numerical results show that this system nearly achieves the
SIR. Both methods are applied to the class of partial
response channels commonly used in magnetic
recording.},
Key = {fds319411}
}

@article{fds319412,
Author = {Hou, J and Siegel, PH and Milstein, LB and Pfister,
HD},
Title = {Design of low-density parity-check codes for bandwidth
efficient modulation},
Journal = {Proceedings 2001 Ieee Information Theory Workshop, Itw
2001},
Pages = {24-26},
Publisher = {IEEE},
Year = {2001},
Month = {January},
ISBN = {0780371194},
url = {http://dx.doi.org/10.1109/ITW.2001.955124},
Abstract = {© 2001 IEEE. We design low-density parity-check (LDPC)
codes for bandwidth efficient modulation using a multilevel
coding (MLC) technique. We develop a method to analyze the
asymptotic performance of the LDPC codes using
message-passing decoding at each level of the MLC scheme as
the codeword length goes to infinity. Simulation of very
large block size LDPC codes verifies the accuracy of the
analytical results. We jointly optimize the code rates and
code parameters of the LDPC codes at each level of the MLC
scheme, and the asymptotic performance of the optimized
irregular LDPC codes is very close to the channel capacity
of the additive white Gaussian noise (AWGN)
channel.},
Doi = {10.1109/ITW.2001.955124},
Key = {fds319412}
}

@article{fds322723,
Author = {Oberg, M and Pfister, HD and Siegel, PH},
Title = {Parity-accumulate codes for magnetic recording},
Journal = {Digests of the Intermag Conference},
Year = {2000},
Month = {January},
Abstract = {A turbo-like architecture for partial-response channels is
presented. The architecture is based on the serial
concatenation of an outer single parity check (SPC) with
uniformly-interleaved rate-1 codes.},
Key = {fds322723}
}

@article{fds319413,
Author = {PFISTER, HL and PFISTER, HD},
Title = {NONCONTACT BODY MEASUREMENT FOR AUTOMATED APPAREL
MANUFACTURING},
Journal = {Factory Automation and Information Management},
Pages = {529-536},
Publisher = {CRC PRESS INC},
Editor = {AHMAD, MM and SULLIVAN, WG},
Year = {1991},
Month = {January},
ISBN = {0-8493-4210-4},
Key = {fds319413}
}



dept@math.duke.edu
ph: 919.660.2800
fax: 919.660.2821

Mathematics Department
Duke University, Box 90320
Durham, NC 27708-0320