Memetic particle swarm optimization algorithm for DOA estimation under multipath environment

This paper introduces a new combine of Memetic particle swarm optimum (MPSO) and beam-space oblique projection operator method suitable for dealing with direction of arrival (DOA) under a multipath environment. Generally, oblique projection operator is applied to project measurements onto a low-rank subspace along a direction that is oblique to the subspace and it enhance signals while nulling interferences. However, the method will be biased under a multipath environment. Therefore, we have proposed the beam-space oblique projection operator by MPSO scheme for DOA under a multipath environment. The MPSO that incorporates local search techniques applies in the particle swarm optimization (PSO) and the procedure as follow: first, we used the PSO to estimate the signal DOA by oblique projection operator method. Second, the personal best position of the swarm to set up beam-space oblique projection operator and using gradient-based techniques to enhance exact. The MPSO uses beam-space rebuilding oblique projection operator for local search techniques to address the issue of reduce multipath effect and increase find exact DOA estimation. Finally, numerical example with different a multipath environment is presented to illustrate the design procedure and to confirm the performance of the proposed method.