Environmentally robust time reversal processing based on multiple constraint method

Abstract

Time-reversal processing (TRP) uses the signals from a probe source to refocus the signal at the probe source location by back-propagating the time-reversed version of the received signal. However, the performance of TRP can be degraded by the mismatches due to the non-static environment where propagation condition changes during the time between receiving a probe signal and back-propagating the time reversed signal. In this presentation, two methods for the environmentally robust TRP based on the multiple signal vectors with singular value decomposition and minimum variance with multiple constraint method has been numerically simulated and compared under the condition of mismatches. Multiple sound speed profile, probe source location and tilted array are used to make the TRP robust. The results show that the focal point using robust TRP is well maintained when compared to the conventional TRP. Both methods are efficient for the robustness of time varying environment.