基于STFD&SCMUSIC的多跳频信号DOA估计与网台分选

为了在欠定条件下利用跳频信号的空域特征参数进行网台分选，该文提出一种基于STFD&SCMUSIC的跳频信号DOA估计算法。首先在时频域提取跳频信号的有效跳(hop)，并建立该hop的空时频矩阵(STFD)；然后在MUSIC算法基础上，利用噪声子空间降维思想构造SCMUSIC空间谱；最终通过半谱搜索实现DOA快速估计，进而利用DOA信息完成信号的分选；同时为了提高低信噪比算法的性能，采用形态学滤波的方法对时频图进行修正，在修正的时频图上完成跳频信号有效hop的提取。理论分析和仿真实验表明了该算法的有效性和良好的估计性能。 

DOA estimation and network sorting based on STFD&SCMUSIC of multi-FH signal

In order to use the spatial characteristic parameter of frequency hopping (FH) signal to realize FH sorting, an FH signal DOA estimation algorithm based on STFD&SCMUSIC is proposed in this paper. Firstly, extract the effective hop of signal from time and frequency domain and establish the spatial-time-frequency distribution matrix of this hop; then construct the SCMUSIC spatial spectrum using descending dimension method of noise sub-space based on MUSIC algorithm; finally realize fast DOA estimation through half-spectrum searching so that FH sorting can be achieved using DOA information. At the same time, the time-frequency map is amended via morphological filtering method in order to enhance performance of low SNR algorithm. Efficient extraction of hop will be implemented on amended maps. Theoretical analysis and simulation results show that this algorithm has good effectiveness and estimation performance.