Publications [#66580] of Jeffrey L. Krolik

Papers Published

1. Harmanci, K. and Krolik, J., Matched window processing for mitigating over-the-horizon radar spread Doppler clutter, 1999 IEEE International Conference on Acoustics, Speech, and Signal Processing. Proceedings. ICASSP99 (Cat. No.99CH36258), vol. vol.5 (1999), pp. 2789 - 92, Phoenix, AZ, USA [ICASSP.1999.761325]
   (last updated on 2007/04/16)

   Abstract:
   Ionospheric motion causes spreading of surface clutter in Doppler space which fundamentally limits the detection performance of skywave HF over-the-horizon radars. This paper presents a technique which reduces the effect of so-called “coincident” spread Doppler clutter, i.e., that which results from surface scattering from within the same range resolution cell as the target. The method exploits the spatial correlation of the ionospheric aberration along the geomagnetic field aligned irregularities to obtain a cross-relation between clutter in neighboring range bins. This cross relation is exploited to estimate the Doppler spreading sequence common to neighboring range bins by a technique adapted from blind multichannel system identification. A Chebyshev Doppler window is then designed which is matched to the estimated ionospheric aberration. Simulation and real data results presented here indicate the proposed method provides as much as 10 dB improvement in side-lobe level using a 3 second coherent integration time radar waveform

   Keywords:
   Doppler effect;electromagnetic wave scattering;HF radio propagation;ionospheric electromagnetic wave propagation;radar clutter;radar detection;radar resolution;sequential estimation;telecommunication channels;