Underwater acoustic model-based signal processing

An underwater acoustic model-based Signal processing algorithm is presented. Its performance was evaluated via computer simulation of various test cases and compared to that predicted by theory. The model-based algorithm, which is used in conjunction with an FFT beamformer for planar arrays, computes phase weights that correct for deterministic, ocean medium, phase effects due to ray bending as a signal propagates in the inhomogeneous ocean medium whose index of refraction (sound-speed profile) is a function of depth. The performance of the model-based signal processing algorithm was evaluated in the context of an underwater acoustic communication problem in order to determine the impact of the model-based algorithm on the probability of detecting single rectangular-envelope continuous wave (CW) and linear frequency modulated (LFM) pulses as a function of the input signal-to-noise power ratio at a single element in the receive array for a given probability of false alarm. Preliminary results for various test cases show significant increases in performance for a correlator receiver.