Papers Published

1. Vasudevan, S. and Krolik, J.L., Refractivity estimation from radar clutter by sequential importance sampling with a Markov model for microwave propagation, ICASSP, IEEE International Conference on Acoustics, Speech and Signal Processing - Proceedings, vol. 5 (2001), pp. 2905 - 2908 [ICASSP.2001.940254] .
   (last updated on 2007/04/16)

   Abstract:
   This paper address the problem of estimating range-varying parameters of the height-dependent index of refraction over the sea surface in order to predict ducted microwave propagation loss. Refractivity estimation is performed using a Markov model for microwave radar clutter returns from the sea surface. Specifically, the parabolic approximation for numerical solution of the wave equation is used to formulate the problem within a non-linear recursive Bayesian state estimation framework. Solution for the conditional expectation of range-varying refractivity, given log-amplitude clutter versus range data, is achieved using a sequential importance sampling technique. Simulation results are presented which demonstrate the ability of this approach to synoptically estimate range-varying refractivity parameters by "through-the-sensor" remote sensing.

   Keywords:
   Electromagnetic wave propagation;Microwaves;Refractive index;Parameter estimation;Markov processes;Mathematical models;Wave equations;Computer simulation;