多通道声呐接收机幅度相位误差补偿方案

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

多通道声呐接收机的预处理电路由于器件的不一致性,会给后端信号处理带来幅相一致性固定偏差。通过对信号参数测量方法的研究,受多通道雷达幅相均衡的启发,提出了一种基于快速傅里叶变换(FFT)的误差补偿方案,采用FFT测量固定偏差和输入水声信号频率,通过复数相乘实现补偿。该方案为一附加现场可编程门阵列(FPGA)模块,对接收机原结构没有影响。仿真结果表明,补偿后的输出信号幅度误差小于1%,相位误差小于1o,且校正附加延时非常小。

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.