Affine projection algorithm with decremental projection order and optimally-designed step size

The proposed algorithm introduces a novel scheme for obtaining an optimal step size and proposes a criterion for decrementing the projection order, which would lead to fast convergence and a small steady-state estimation error with low computational complexity. The scheme is based on an analysis of the mean square deviation (MSD) for the tap weight and its estimated value at each iteration. The criterion is obtained by calculating the steady-state MSD. Experimental results show that the proposed algorithm has faster convergence and a smaller steady-state error than the existing affine projection algorithms with a variable step size or variable projection order.