Modified wiener filter for direction of arrival estimation

When the underwater environment is complicated and the Signal-to-Noise Ratio (SNR) is low, the performance of the Direction Of Arrival (DOA) estimation is poor. To tackle this problem, we propose a spatial-temporal filter based on the modified Wiener filter and the beamforming method to reduce the received noise and estimate the DOA in the low SNR environments. First, the received data is processed by the modified Wiener filter. As a result, the noise is reduced in the time domain. Second, the output data of the modified Wiener filter is processed by the beamforming method. As a consequence, the noise is reduced in the spatial domain. Furthermore, we can obtain the best performance of the DOA estimation by adjusting the modified Wiener filter parameter. The simulation and experimental results show that the output SNR is increased and the Root-Mean-Square Error (RMSE) of the DOA estimation is decreased.