The azimuth-Doppler distribution characteristics of the low-frequency reverberation on the platform-movement condition

The Space-Frequency coupling structure of platform-movement reverberation is important for suppressing LFAS (Low-Frequency high-power Active Sonar systems) reverberation and thereby improving its low-speed target detection performance.The high-resolution spectral analysis methods (e.g.MUSIC and Capon) are used to the beamformer-output reverberation sequences in order to overcome the restraint of the pulse width and hence obtain the LF (low-frequency) reverberation bearing-Doppler distribution more accurate.The South China sea-trial data analyses show that the shallow-water LF reverberation distribution exactly conforms to the Doppler effect and with the feature that its frequency-spread will decrease as the strength tends to increasing in the range-azimuth discrimination cells.Furthermore,the starboard-port reverberation separation characteristics of the platform yaw-moving conditions are deduced according to the Doppler effect and well matched by the experiment results of the same sea-trial.