A low complexity proportionate affine projection algorithm for echo cancellation

Proportionate-type affine projection algorithms were developed in the context of echo cancellation, as a generalization of the proportionate-type normalized least-mean-square algorithms. A matrix inversion is required within the affine projection algorithm (APA). In the case of proportionate-type A PAs, the update of the matrix to be inverted is very computationally expensive. In this paper, an efficient update of this matrix is proposed and the procedure is applied for a recently developed proportionate-type APA. It is shown that the proposed algorithm achieves similar performance but significantly lowers numerical complexity as compared to known proportionate-type APAs.