提出了面阵中基于降维Capon 的二维波达方向(direction of arrival, DOA) 估计算
法. 先求得接受信号的协方差矩阵，再对其变换式进行谱峰搜索估计出一个参数，进而通过最
小二乘估计出第2个参数. 采用一维全局搜索实现二维DOA的联合估计，可避免二维Capon
算法由二维谱峰搜索带来的巨大计算量，从而大大降低了计算复杂度，且角度估计性能非常
接近于二维Capon 算法. 该算法既可以实现二维角度的自动配对，又可以精确地估计出相同
方位角(或仰角)的信源，其优越性均可在文中得到验证.
This paper discusses estimation of two-dimensional (2D) direction of arrival
(DOA) for a planar array, and derives a reduced-dimension Capon (RD-Capon) algorithm.
The first parameter is obtained by searching the spectrum peak of transformation of the
covariance matrix, obtained from the received signal. The second parameter is estimated
using least squares. The algorithm uses one-dimensional global search to achieve a joint estimation
of 2D DOA. This algorithm based on one-dimension local searches can avoid high
computational cost within 2D-Capon algorithm by spectrum peak search, with the performance
close to the 2D-Capon algorithm. The proposed algorithm can obtain automaticallypaired
2D DOA estimation for planar array. It works well for the sources with the same
azimuth (or elevation). Simulation results verify the usefulness of the algorithm.
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