邻近强干扰下波达方向的梯度下降估计算法

DOA estimation algorithm based on gradient descent method for signal under strong adjacent interference

针对目标信号邻近方向存在强干扰的问题,在已知目标信号部分先验信息的条件下,提出一种基于梯度下降的波达方向估计算法。该算法首先构建斜投影算子分离非正交的目标信号和干扰信号,然后利用干扰信号和目标信号的功率差异以及目标信号的相关特性,设计梯度下降算法,实现干扰信号与目标信号波达方向的联合迭代估计。仿真结果表明,该算法在干扰信号与目标信号波达方向接近的场景中,能够实现对目标信号波达方向的准确估计,估计性能优于MUSIC算法和RELAX算法,并且具有较低的计算复杂度。

The algorithm of direction-of-arrival（DOA）estimation for the signal under strong adjacent interference is proposed based on gradient descent method,where partial information about the target signal is known.Firstly an oblique projection operator is constructed to separate the non-orthogonal target signal and the interference signal.Then the power difference between the interference signal and the target signal,and the correlation of the target signal are utilized to design a gradient descent algorithm which can achieve a joint iterative DOA estimation of both the interference signal and the target signal.The simulation results show that the given algorithm can accurately estimate DOA of the target signal in the case where the interference signal is close to the direction of the target signal.The proposed algorithm outperforms the MUSIC algorithm and the RELAX algorithm under the scenario of strong adjacent interference and partial information available about target signal.It is also shown that compared to MUSIC algorithm,the given algorithm has lower computational complexity.