基于实数遗传算法的波达方向最大似然估计算法

摘要

The problem of obtaining the high resolution direction of arrival(DOA) estimation of narrow-band sources lying in the far field of the array is one of the central problems in radar, sonar and seismology. To overcome the local optimal problem existing in some maximum likelihood DOA estimation algorithms, improve the estimation accuracy, a global optimal solution of nonlinear maximum likelihood DOA estimation is obtained by real-valued genetic algorithm proposed in this paper. The proposed real-valued genetic algorithm is composed of real-valued crossover and mutation operators constructed with the information of real number field and objective function. And it is an ideal method for searching the global solution of non-linear real variable functions. Simulational results of non-herent and coherent sources DOA estimation show that the algorithm is better in accuracy over some conventional DOA estimation algorithm, such as the well-known alternating projection method.%对空间多个窄带信号源的高分辨波达方向估计是雷达、声纳和地震等信号处理中的重要问题之一。为克服一些获取波达方向估计最大似然解算法存在的局部极值问题，提高估计精度，本文以作者提出的实数遗传算法为搜索工具，寻求波达方向最大似然估计的非线性全局最优解。所提出的实数遗传算法由含实数域结构和目标函数信息的实数交叉和变异算子构成，是较理想的获取非线性实变量函数全局最优解的方法。对非相参和全相参信源波达方向估计问题的数字仿真结果表明，本方法的估计精度明显优于交替极值等一些常规方法。