一种高效稳健的均匀圆阵互耦校正方法

紧凑均匀圆阵（UCA）的强电磁互耦效应严重影响波束赋形（BF）和波达方向（DoA）估计的性能，本文利用UCA的特殊圆对称性，提出了一种稳健高效的互耦参数校正方法.该方法只需要单个信源和单次校正实验，并且信源方向并不需要事先精确校准.首先互耦矩阵在离散傅里叶空间被转化为具有中心对称的一个参矢量，随后在一个有限的先验二维空间角域内进行搜索，从而根据基于对称性的目标函数将互耦参数估计出来.仿真对比实验验证了新校正算法的有效性和鲁棒性，同时揭示了秩损（RARE）校正方法不够稳健，为基于UCA的雷达、移动通信等应用提供了简单且高效的互耦误差校正方法.

An Efficient and Robust Calibration Method of Mutual Coupling for Uniform Circular Array

The strong electromagnetic mutual coupling effect of a compact uniform circular array (UCA) will severely degrade the performance of beamforming (BF) or direction-of-arrival (DoA) estimation.Based on the special circular symmetry of a UCA,a new efficient and robust calibration method is proposed for the mutual coupling effect.Only one single signal source and one trial are required to complete the calibration,and the direction of the signal source does not need to be calibrated beforehand.First in discrete Fourier transform (DFT) space,the mutual coupling matrix (MCM) is transformed to be a centrosymmetric vector.Then in a prior 2D spatial angular domain,limited angle searching is carried out to get the estimate of the parameters according to a novel objection ftnction based on the symmetry.Comparative simulations verify the effectiveness and robustness of the new algorithm and at the same time reveal that method based on rank reduction (RARE) lacks robustness,and thus a simple and efficient approach for mutual coupling calibration is provided when UCA is applied in radar,mobile communication system etc.