Dai Zhengliang, Cui Weijia, Ba Bin, Wang Daming, Sun Youming
National Digital System Engineering and Technological Research R&D Center, Zhengzhou 450001, China.
Sensors (Basel). 2017 Jun 6;17(6):1300. doi: 10.3390/s17061300.
In this paper, a novel algorithm is proposed for the two-dimensional (2D) central direction-of-arrival (DOA) estimation of coherently distributed (CD) sources. Specifically, we focus on a centro-symmetric crossed array consisting of two uniform linear arrays (ULAs). Unlike the conventional low-complexity methods using the one-order Taylor series approximation to obtain the approximate rotational invariance relation, we first prove the symmetric property of angular signal distributed weight vectors of the CD source for an arbitrary centrosymmetric array, and then use this property to establish two generalized rotational invariance relations inside the array manifolds in the two ULAs. Making use of such relations, the central elevation and azimuth DOAs are obtained by employing a polynomial-root-based search-free approach, respectively. Finally, simple parameter matching is accomplished by searching for the minimums of the cost function of the estimated 2D angular parameters. When compared with the existing low-complexity methods, the proposed algorithm can greatly improve estimation accuracy without significant increment in computation complexity. Moreover, it performs independently of the deterministic angular distributed function. Simulation results are presented to illustrate the performance of the proposed algorithm.
本文提出了一种用于相干分布（CD）源二维（2D）中心到达方向（DOA）估计的新算法。具体而言，我们关注由两个均匀线性阵列（ULA）组成的中心对称交叉阵列。与使用一阶泰勒级数近似来获得近似旋转不变关系的传统低复杂度方法不同，我们首先证明了对于任意中心对称阵列，CD源的角信号分布权重向量的对称特性，然后利用该特性在两个ULA的阵列流形内部建立两个广义旋转不变关系。利用这些关系，分别采用基于多项式根的免搜索方法获得中心仰角和方位角DOA。最后，通过搜索估计的二维角参数的代价函数的最小值来完成简单的参数匹配。与现有的低复杂度方法相比，该算法在不显著增加计算复杂度的情况下可以大大提高估计精度。此外，它的性能与确定性角分布函数无关。给出了仿真结果以说明所提算法的性能。
