The conventional algorithms of sound source bearing estimation are based on the premise that the sound propagates as plane wave, the wave form received by each sensor is the same only the time delay is different. But in a waveguide such as the shallow water channel sound propagates in terms of the normal modes, each of the modes can be interpreted as a horizontal line array plane wave arriving at the receiver at a certain vertical incident angle, which cause the multipath effect. In this situation, the premise of the conventional DOA estimation method is not satisfied. In this paper, multipath effect in shallow water channel is analyzed based on normal mode theory, and the influence of multipath effect in shallow water channel on DOA estimation is analyzed. Finally, the conclusions of the theory analysis are tested by several numerical examples.
展开▼
