Active sonar approximate coherence processing algorithm based on COSTAS waveform
In order to improve the detection of detection processing,effective against the frequency selectivity of the water channel,this text proposed a new algorithm based on the COSTAS waveform.This article first analyzes the principle of coherent fusion,and then based on the assumption that similar frequencies experi-ence approximately coherent channels,it proposes to apply approximate coherent fusion to sonar echo signal processing.The specific implementation method is as follows:Enhance the echo through frequency domain beamforming wave gain;Correlation processing through normalized matching filtering;Weighted summation of complex numbers of different frequencies after matching filtering,and the weighting coefficient is determined by the signal-to-noise ratio.Simulation shows that the receiver curve of the approximate coherent algorithm proposed in this article is significantly better than that of non-coherent processing;at the same time,the lake test results prove that the approximately coherent method has a higher processing gain than the existing non-coherent processing method.The gain is increased by 5-9 dB.
COSTAS signalUnderwater acoustic detectionActive sonar detectionFrequency selective fadingHigh gain
万方数据
维普
