Ideal sensor response is always desirable in multiple-input multiple-output (MIMO) system. In practical application, however, sensors may be susceptible to unknown mutual coupling (MC), which seriously decreases the angle estimation accuracy. This letter addresses the scenario where MIMO sensors are corrupted by the direction-dependent MC effect. Taking the banded symmetric and Toeplitz characteristics of the MC matrices into consideration, a closed-form algorithm is introduced for angle estimation. The core of the proposed algorithm is to release the MC effect via selection matrices, and then obtain the angle by exploiting rotational invariance techniques. The proposed algorithm is capable of automatically paired angle estimation in MIMO system with direction-dependent MC, and it is much more efficient than current spectrum search approach. The numerical results show the validity and superiority of the proposed method.

中文翻译：

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具有方向相关互耦的 MIMO 系统中的快速角度估计


在多输入多输出 (MIMO) 系统中始终需要理想的传感器响应。然而在实际应用中，传感器可能容易受到未知互耦（MC）的影响，从而严重降低角度估计精度。这封信解决了 MIMO 传感器被方向相关的 MC 效应损坏的情况。考虑MC矩阵的带状对称性和Toeplitz特性，引入闭式角度估计算法。该算法的核心是通过选择矩阵释放MC效应，然后利用旋转不变性技术获得角度。该算法能够在具有方向相关MC的MIMO系统中自动进行配对角度估计，并且比当前的频谱搜索方法更加高效。数值结果表明了该方法的有效性和优越性。