改进仿射投影算法及其在电子回声消除中的应用

在电子回声消除应用中,为提高自适应算法的收敛速度,提出一种改进的仿射投影算法及其快速实现形式.新算法利用回声路径的稀疏结构特征,通过收敛步长控制矩阵,按滤波器各系数幅值大小,等比例地为其指定相应收敛步长,以加快大系数收敛,最终达到加快滤波器整体收敛速度的目的.对新算法进行的统计学分析,为其快速收敛于目标系统的算法特性提供了理论依据.仿真实验表明与传统自适应算法相比,新算法能减小稳态失调并大幅提高收敛速度,其低计算复杂度亦保证了系统的实时性.

An Improved Affine Projection Algorithm and Its Application in Network Echo Cancellation

An improved affine projection algorithm for network echo cancellation with its fast version is proposed to increase the convergence speed.On the basis of the sparse structure characteristic of network echo path,each coefficient of adaptive filter in the new algorithm obtains different step-size in proportion to its current absolute value,which leads to high overall convergence speed.Statistical analysis of the new algorithm provides theoretical basis for its outstanding capacity in converging to the objective system.The simulation result verifies that the new algorithm achieves faster convergence speed and lower final misalignment.In addition its low computational complexity satisfies the requirement of real-time system.