基于空时DFT投影实现宽带信号二维角估计

Two-Dimensional Angles Estimation of Wide-Band Signals with Spatial-Temporal DFT Projection

提出了一种基于空时DFT投影的宽带信号二维角估计算法 .该方法采用 3个共面的均匀线阵 ,每一均匀线阵对宽带信号空间采样 ,然后进行空时二维DFT变换 ,在空时频率域对宽带信号进行投影变换 ,用MUSIC算法实现宽带来波信号方向余弦的估计 .利用 3个方向余弦估值进行配对 ,然后求得来波的方位角和仰角估计 .该方法既保留了投影算法的优点 ,即不需要源的先验知识 ;不需变换矩阵和在低信噪比有好的性能 ,又避免二维谱峰搜索 .仿真实验表明了算法是有效的 .

A new method of estimation two dimensional angles of wide band arrival signals is presented with spatial temporal DFT projection. The sensor array is consisted of three coplanar uniform linear arrays (ULA). For every ULA, the wide band signals are sampled in spatial and temporal, then 2 D discrete Fourier transform is carried out. A projection operation on 2 D representation of wide band signals is applied in the spatial temporal frequency domain. The direction cosine relative to the ULA axes is estimated by MUSIC algorithm. Using the direction cosines relative to three ULA axes, the correct pair is obtained, then the azimuth and elevation are estimated. The method has the advantages of projection method that does not require any a prior information about sources and does not require transformation matrices and has good performance at low SNR, and does not require 2 D spectrum searching. Simulation experimental results are presented demonstrating the capabilities of the method.