Compensation Scheme of Amplitude-Phase Error for Multi-Channel Sonar Receiver

The inconsistency of pretreatment circuit components of a multi-channel sonar receiver may bring fixed deviation of amplitude-phase consistency to the signal processing at backend. Inspired by the amplitude-phase equilibrium of a multi-channel radar, the authors analyze the measurement methods of signal parameters, and present an error compensation scheme based on fast Fourier transform(FFT). In this scheme, FFT is employed to measure the fixed deviation and the frequency of input acoustic signal, and the compensation is hence achieved by complex multiplication. The scheme is an additional field programmable gate array(FPGA) module without any influence on the original structure of a receiver. Simulation shows that the amplitude error of output compensated signal is less than 1%, the phase error is less than 1°, and the additional time delay of correction is very small.