针对实际工作中波束合成性能下降的问题,推导了理想情况下数字波束合成信噪比相对输入信噪比的增益,研究了 通道失效、幅度加权和幅相误差分别对波束合成信噪比的影响,并推导了信噪比损失的解析式。理论分析和仿真结果表 明:在失效通道比例小于30%的条件下,信噪比损失与失效通道比例近似成线性关系;在同时存在通道失效、幅度加权和 幅相误差的条件下,信噪比损失近似等于通道失效、幅度加权和幅相误差各自引入的信噪比损失之和。

Considering the signal noise ration (SNR) loss of beam forming in practice, the SNR gain of digital beam forming is derivated under the ideal case in this paper. The factors of channel failure, amplitude weighting and amplitude-phase error, which can cause SNR performance deterioration of beam forming, are respectively studied, and the analytical expression of SNR loss is derivated. The simulation results indicate that it is approximately linear dependency between SNR loss and channel failure when the percent of disabled channel is below 30%; the SNR loss resulted from the simultaneous existence of channel failure, amplitude weighting and amplitude-phase error is approximately the sum of SNR loss resulted from them respetively.