提出了一种将信号相位匹配原理和遗传算法相结合的信号波达方向估计方法.根据信号相位匹配原理的最小二乘解所确定的期望信号能量函数,设计了遗传算法的适应度函数.分析了不同信噪比下阵元数和FFT序列长度对波达方向估计精度的影响,给出了不同信噪比时波达方向估计的Monte-Carlo实验结果.计算机仿真表明,该方法不但可在360°范围内快速搜索波达方向,而且还能同时对信号频率进行参数估计.只估计波达方向时,在信噪比为0dB、8阵元、1024点FFT和种群规模为20的情况下,20代遗传进化就可搜索到精度较高的波达方向;同时进行方向和参数估计也取得较好的效果,证明了该方法的有效性.
To rapidly estimate DOA (direction of arrival) within the scope of 360 degrees using the signal phase-matching principle, we propose a genetic searching algorithm whose fitness function is designed by the energy function constructed from the least squares solution of the expected signal. Effects of the array element's number and the sequence length of FFT on the estimation accuracy of DOA were analyzed by Monte-Carlo experimented data under different signal-to-noise ratios (SNR). Computer simulation results show that this method can estimate DOA and parameters of the signal frequency synchronously. When only DOA is estimated, the evolution of twenty generations can execute this task with good accuracy in the case of 0 dB SNR, 8 array elements, 1024 FFT and 20 individuals in population.