一种改进的变步长仿射投影算法

A Modifled Variable Step-Size Affine Projection Algorithm

变步长的仿射投影算法因具有较传统仿射投影算法收敛快、失调小等优点而受到广泛重视。但是因计算量较大,限制了其在实际中的应用。为降低计算的复杂性和减少计算量,该文根据权值部分更新和步长间歇更新的思想提出一种改进方案,即根据某些原则仅选择部分权值进行更新以及每L次迭代只更新一次步长。文中通过一个具有有色输入的线性系统的辩识验证了改进方法的性能。仿真结果表明,改进算法在保证计算收敛性和计算精度的情况下,可有效地减少计算量。

Variable step - size affine projection algorithm with faster convergence and lower mis - adjustment is investigated broadly. However, the application of the algorithm is restricted by the large computational complexity in practice. To improve the operational characteristics, a modified version is presented by employing weights partial updating and step - size interim updating, i.e. selecting partial weights according to certain principle and changing the step - size once per L iterations. The performance of the algorithm is checked using a system identification simulation with colored input. The result indicates that the computational expense of the proposed algorithm can be reduced effectively with a guarantee of convergence and precision.