Affine Projection Algorithm With Variable Projection Order
Increasing the projection order in the affine projection adaptive filtering algorithm speeds up the convergence but also increases the steady-state misalignment. To address this unfavorable compromise, the authors propose a new affine projection algorithm with a variable projection order. This algorithm adaptively changes the projection order according to the estimated variance of the filter output error. The error variance is estimated using the exponential window and moving averaging techniques and employing a variable forgetting factor.