基于Laguerre滤波器等价设计的IIR宽带波束形成

常规IIR宽带波束形成器可以获得比FIR宽带波束形成器更好的性能,但其需要多极点的自适应调整过程,存在稳定性无法保证,计算复杂度较高等问题.本文提出一种新的基于IIR滤波器的宽带波束形成算法.该算法基于高阶Laguerre宽带波束形成器,利用双线性变换和函数束方法设计相应的低阶等价IIR宽带波束形成器.仿真实验及理论分析表明,该方法无需常规IIR宽带波束形成器的多极点自适应调整过程,在保证算法稳定性的同时,减少了计算复杂度,并提高了输出信干噪比(SINR).

A Novel IIR Wideband Beamforming Algorithm Based on the Equivalent Design of Laguerre Filter

Conventional broadband beamforming structures make use of finite-impulse-response(FIR)filters in each channel.It has been proven that the optimal frequency-dependent array weightings of broadband beamformers could be better approximated by infinite-impulse-response(IIR)filters.However,some potential problems,such as stability monitoring and the high computational complexity,of the IIR filters due to the adaptive algorithm required to adjust the poles make the implementation of the IIR beamformers difficult.In this paper,a novel broadband IIR beamformer is proposed to solve these problems.Based on the high order Laguerre beamformer,an equivalent lower order IIR beamformer is designed by using the method of bilinear transformation and pencil-of-functions.The simulations illustrate that without the process of adjusting the poles,the proposed method can ensure the stability,reduce the computational complexity and improve the output SINR.