应用于双滤波器结构的活跃系数定位算法

Active Coefficient Locating Algorithm for Dual-filter Structure

为提高定位精度,提出用移动窗积分进行活跃系数定位的算法。结合双滤波器结构,利用一级滤波器W1(k)辨识目标系统,对W1(k)进行平方与移动窗积分运算,以最大积分值区间作为活跃系数位置。二级滤波器W2(k)在时域对应活跃系数位置,以精确辨识活跃系数。仿真实验结果表明,与传统定位算法相比,该算法充分利用回声路径的稀疏性,可提高定位精度,使W2(k)有效覆盖所有活跃系数,达到提高收敛速度、降低稳态失调现象的目的。

A new algorithm using Moving Window Integration （MWI） for locating active coefficients is proposed to improve the location accuracy. Combined with the dual-filter structure, the new algorithm uses the first filter Wr （k） to identify the objective system. The square values and moving window integration of W2 （k） are caculated. The region with the maximum is determined to be the active coefficient region. A second filter W2 （k） is used to accurately identify the active coefficients belonging to the located region. Experimental simulation is conducted under the application background of echo cancellation. The results show that compared with the traditional location algorithm, the new algorithm improves the location accuracy and enables W2 （k） to cover all active coefficients exactly, which eventually leads to faster convergence speed and lower misalignment.