Adaptive Combination of Distributed Incremental Affine Projection Algorithm with Different Projection Orders

Recently, the distributed incremental affine projection algorithm (DIAPA) has attracted much attention owing to its good performance for correlated input. However, the DIAPA algorithm with high projection order achieves fast convergence rate but suffers from large steady-state misalignment, and that with low projection order has small steady-state misalignment, but it converges slowly. To overcome this trade-off, in this brief, an adaptive combination of the distributed incremental affine projection algorithm with different projection orders (ACDIAPA-DPO) is proposed, which combines the DIAPA using high projection order with that using low projection order by an adaptive mixing parameter. The mixing parameter is obtained by minimizing the mean square deviation. We discuss the computational complexity of the proposed algorithm and other existing algorithms. Moreover, a novel re-initialization mechanism is introduced to further improve the tracking capability of the ACDIAPA-DPO when the system suddenly changes. Simulations results over the incremental network show the superiority of the proposed algorithm.