Abstract:

The detection performance of the channel-sensitive processor (CSP) [D. Alexandrou and G. Haralabus, SACLANTCEN Report No. SR-263 (1997)] has been tested in dense multipath conditions. It has been demonstrated that for a known propagation channel the CSP method outperforms the conventional matched filter technique. However, in an uncertain environment, the probability of detection of CSP degrades according to the degree of mismatch between the assumed and the actual channel characteristics. It has been found that the processor is more sensitive to geometric parameters (source range and depth) than to environmental parameters (sound velocity profile, sediment-subbottom interface, sediment depth). To overcome the performance degradation due to channel mismatch, the CSP method has been utilized in conjunction with two nonlinear optimization algorithms: the classical simulated annealing (SA) and the multilayer simulated annealing (MUSA) method. At the expense of processing time, it has been found that the optimization methods reduce the channel mismatch effect and considerably improve the detection performance of the CSP.