一种新变步长LMS算法及在自适应波束形成中的应用

LMS算法是智能天线自适应波束形成算法中的经典算法,由于其步长固定,造成收敛速度和稳态失调之间的矛盾。为了解决这一问题,提出一种新的变步长LMS算法,并在算法中引入误差信号的自相关估计,大大降低了噪声的干扰,对算法进行仿真,得到了最优的参数设置。利用蒙特卡罗方法对算法进行了性能评估,与传统的LMS算法、NLMS算法相比,新的变步长LMS算法具有更快的收敛速度和较小的稳态误差及优良的抗噪性能。

A New Variable Step LMS Algorithm and Its Application in Adaptive Beamforming

LMS algorithm is classical adaptive beamforming algorithm in smart antenna.Constant step in algorithm leads to the contradiction between convergence speed and maladjustment error.So a new variable step LMS algorithm is proposed.By introducing autocorrelation estimation of signal error,the noise interference is suppressed strongly.Optimal parameters are learned by simulation.Compared with constant step LMS and NLMS algorithms,the new variable step LMS algorithm has faster convergence speed,lesser maladjustment error and more excellent anti noise performance by using the Monte Carlo method for evaluing algorihm performance.