一种变阶数自适应滤波算法

Adaptive filter based on coefficient order control and applied to acoustic echo cancellation

通过对回声抵消的实际应用环境进行分析,提出一种新的动态改变自适应滤波器阶数的算法。该算法在权系数的长度与失调误差信号之间建立一种非线性函数关系,具有在环境突变阶段,保持较高的滤波器阶数,而在稳态阶段自动减少阶数的特点,可以极大地降低自适应滤波器算法的运算量。理论分析和计算机仿真结果表明,该算法具有良好的收敛性能和跟踪性能,稳态误差的水平与传统算法保持一致。

By analysing the actual room acoustic environments, this paper presents a novel algorithm for acoustic echo cancellation, it can dynamically change the length of the adaptive filter order. This algorithm builds a nonlinear function relationship between the length and the error signal. The filter keeps a long order when the environment changes suddenly, and the length would be shorter during the steady state. A significant reduction in the computational burden can be achieved by using the new method. Theoretical analysis and computer simulation prove that the convergence and tracking properties of this algorithm is as good as the former ones.