Efficient implementation of the Affine Projection algorithm for Active Noise Control applications

In this paper, an efficient implementation of the Affine Projection algorithm (AP) is introduced in order to avoid the direct computation of matrix inversions. In the presented formulation, a recursive relation is devoted to calculate matrix inversion, thus improving the computational load (as much improvement as greater projection order). Furthermore, the proposed AP version has been introduced for multichannel Active Noise Control (ANC) and the new algorithm is named new efficient multichannel filtered-x affine projection algorithm (new efficient MFXAP). A comparative practical study of different AP implementations with the new approach has been also carried out and validates the use of the proposed method. Simulations and a practical implementation based on the TMS320C40 DSP took part in this study. The most meaningful results are shown throughout the paper.