新型拉伸电磁矢量传感器的两维高精度波达方向估计

High accuracy 2D DOA estimation with a novel spatially spread electromagnetic vector-sensor

较之传统的共点电磁矢量传感器,拉伸电磁矢量传感器能够显著降低阵元间互耦,且非共点结构在硬件设计上更易于实现。但是现有拉伸电磁矢量传感器无法实现阵列的两维孔径扩展,导致了两维波达方向估计精度较差。针对此问题,提出一种新型的拉伸电磁矢量传感器。该阵列结构由单个拉伸电磁矢量传感器和单个电偶极子组成。利用单个拉伸电磁矢量传感器提供一维孔径扩展,再利用垂直于该拉伸电磁矢量传感器的单个电偶极子实现另一维的孔径扩展。针对该两维孔径扩展阵列,提出一种矢量叉积算法与相位干涉法相结合的算法来获取两维波达方向的高精度估计。所提阵列在降低互耦的同时,利用电磁矢量传感器提供的极化分集与两维孔径扩展带来的空间分集,使得两维波达方向估计精度大大提高。

The spatially spread electromagnetic vector-sensor（EMVS）can greatly reduce the mutual coupling and the hardware cost compared with the traditional collocated EMVS.However,the existing spatially spread EMVS can only extend one dimensional（1D）array aperture,and this is insufficient for the 2D direction of arrival（DOA）estimation.To solve this problem,a new spatially spread EMVS configuration is proposed to extend 2D array aperture and improve 2D DOA estimation accuracy.This array configuration is composed of single spatially spread EMVS and single dipole.The single spatially spread EMVS offers the 1Darray aperture extension,and the single dipole,which locates verticaly to the single spatially spread EMVS,offers another 1D array aperture extension.This array configuration creatively synergizes the＂vector-cross-product＂algorithm and the conventional interferometry method to enhance the DOA estimation accuracy.The proposed configuration not only greatly reduces the mutual coupling,but also improves the 2D DOA estimation accuracy taking advantages of the polarization diversity offered by vector-sensor and the spatial diversity offered by the extended aperture array.