阵元一致性对水听器阵列信噪比增益的影响

摘要：研究了水听器阵列中阵元的一致性对信噪比增益的影响因素,一致性意味着当输入信号相同时,各阵元具有相同的输出,即相位与幅度响应均相同。给出了增益与信号、增益噪声互相关系数的关系。从理论上对阵元存在幅相不一致时的阵增益进行了分析,推导了信号为单频时,2元阵的的增益表达式,并给相位差在10°与幅度差为3dB时的增益。通过仿真对理论分析进行了验证,总结了当幅相一致性变化时,信噪比增益的变化规律,即水听器阵列信噪比增益受到阵元一致性的影响较大,增益随幅相一致性变差而降低,且幅度响应一致性进一步变差时,增益值将为负值。
Abstract： The influence of array element’s consistency on the hydrophone array’s signal-to-noise ratio (SNR) is studied. The consistency of array elements means the outputs of all the array’s elements are the same, that is to say, the outputs have the same phase and amplitude when their inputs are the same. The relationship between the SNR and the correlation coefficient of signal and the relationship between the SNR and the correlation coefficient of noise are given. Hydrophone array’s gain with the output of elements’ inconsistent phase and amplitude is analyzed theoretically. When the signal is single-frequency, the gain expression of two-elements array is deduced. Then the gain is calculated when the phase difference is 10° and the amplitude difference is 3 dB. The theoretical analysis is verified through simulation. The simulation results show the variation rule of array’s SNR when the consistency changes: the array SNR gain is greatly affected by the consistency of the elements’ output and the gain decreases as the consistency decreases and the gain may be negative when the amplitude response becomes worse.