Signal processing for precise ocean mapping

In this work a bottom return signal model and accompanying signal processor are described for a wide swath bottom mapping system. An incoherent scattering model is employed under the assumptions that the bottom is a random rough surface composed of a large number of independent scatters with spatial correlation distance negligible relative to the ensonified area. The envelope of the signal received from the various spatial directions is modeled as a smooth, nearly Gaussian-shaped function representing the effects of the twoway spatial beam pattern, angle of incidence, and depth corrupted by multiplicative and additive noise stochastic processes. A signal processor is derived which makes use of the a priori information vested in this smooth function to provide a matched filter for the received signal envelope for each spatial direction. Computer simulation results are presented and the performance of the signal processor examined in a qualitative fashion.