一种基于空间时频分布的波达方向估计方法

基于信号空间时频分布的到达角（DOA）估计算法利用Cohen类分布构造时频分布矩阵代替传统的阵列协方差矩阵，既适用于平稳信号的场合又适用于时变、非平稳信号的情形。如何在时频分布矩阵中选择合适的时频点是此类算法的关键。分析了信号项选择和联合对角化的原理，并通过无约束最优化方法在时频平面上寻找单信号项的时频点，通过时频MUSIC方法对线性调频信号进行DOA估计，仿真结果证实了该方法的有效性。

A Method of Direction-of-Arrival Via Spatial Time-frequency Distribution

Based on the spatial time-frequency distribution of signals,direction of arrival method uses the Cohen class time-frequency distribution to construct the time-frequency correlation matrix DXX(t,f) to replace the traditional correlation matrix RXX.The method is suitable for both stationary and time-variation nonstationary signals,how to select appropriate time-frequency locations is the key point of this kind of DOA methods.The paper analyses the principle of auto terms selection and joint-diagonalization.An unconstrained optimization method is used to find the time-frequency location of single auto terms(SAT),time-frequency MUSIC is used to estimate DOA of chirp signal.The simulation results show the effectiveness of the method.