DFT宽带波束形成器简化权系数法性能分析

Performance Analaysis of DFT Wideband Beamforming Using Simplified Weight Coefficient Distribution Method

由于处理芯片内存空间是有限的,在实际声呐和雷达信号处理机中应用DFT宽带波束形成器时,通常采用简化权系数分配法降低加权向量的存储量,使其能够完全存储于处理芯片的内存中,为处理机的实时性提供了可靠保证。简化权系数分配法会降低波束形成器的阵增益,并使得输出信号产生相位差,从而影响系统检测和估计性能。本文给出了该近似方法的性能分析,并通过仿真实验验证了其对阵增益和相位的影响,最后结合仿真结果说明如何进行相位补偿以及如何选取简化权系数法的频段宽度以保证系统的稳健性。

In order to make sure that the system can work in real time,the DFT wideband beamformer using simplified weight coefficient distribution method is usually applied in practical sonar or radar system. This method can greatly reduce the memory of the storage of weight coefficients. Compared with traditional method,simplified metod gready decreases the Array Gain of heamformer and results in the phase offset. In this article ,the performance analysis of thismethod is presented. PC based simulation results validate the theoretical performance analysis of Array Gain and the phase offset, and illuminate how to select parameter of the simplified weight coefficient distribution method and how to compensate the phase offset to keep system robust.