Matched-field inversion of sound speed profile in shallow water using a parallel genetic algorithm

A sound speed profile plays an important role in shallow water sound propagation. Concurrent with in-situ measurements, many inversion methods, such as matched-field inversion, have been put forward to invert the sound speed profile from acoustic signals. However, the time cost of matched-field inversion may be very high in replica field calculations. We studied the feasibility and robustness of an acoustic tomography scheme with matched-field processing in shallow water, and described the sound speed profile by empirical orthogonal functions. We analyzed the acoustic signals from a vertical line array in ASIAEX2001 in the East China Sea to invert sound speed profiles with estimated empirical orthogonal functions and a parallel genetic algorithm to speed up the inversion. The results show that the inverted sound speed profiles are in good agreement with conductivity-temperature-depth measurements. Moreover, a posteriori probability analysis is carried out to verify the inversion results.