Maximum likelihood estimation of multi-path DOA and fading coefficient
多径相干信号到达角和衰落系数的最大似然估计

Focusing on estimating the direction of arrivalDOAand fading coefficientFCin multi-path coherent signal environment, this paper proposed a new approach by using the improved maximum likelihood estimationIMLE. This method estimated DOAs of multi-path coherent signals by using IMLE, gained FC and deduced Cramér-Rao boundary of IMLE. In order to drop the computational complexity of IMLE, used an alternating maximizationAMmethod to reduce dimensions of the search space. The theoretical analysis and experimental results show that the proposed approach has better estimation performance than existing methods. Even if DOAs of multi-path coherent signals coming from different emitters are identical, the presented approach has still a good estimation effect.