中文摘要：

针对单基地多输入多输出（multiple input multiple output,MIMO）雷达波达方向（direction of arrival,DOA）估计问题,该文提出一种低复杂度的实值求根多重信号分类（multiple signal classification, MUSIC）方法。该方法首先通过降维变换降低接收数据的维数,利用酉变换将复值数据协方差矩阵实值化,然后构造基于酉MUSIC的求根多项式,采用保角映射将复系数多项式映射为实系数多项式,最后通过求解该实系数多项式的根来得到目标的DOA估计。该方法不需要进行谱峰搜索,所涉及的特征值分解和多项式求根运算均只在实数域进行,在大大降低算法运算复杂度的同时可以获得更好的角度估计性能。仿真结果验证了所提算法的有效性。

英文摘要：

A low complexity direction of arrival （DOA） estimation method based on the real-valued root-multiple signal classification （MUSIC） algorithm is proposed for DOA estimation in monostatic multiple input multiple output （MIMO） radar. Firstly, the dimension of the received data is reduced by the reduced-dimensional transformation and the real-valued covariance matrix of the received data is obtained by unitary transformation. Then a unitary MUSIC-based polynomial is constructed in the low-dimensional space to estimate the DOA of targets. To further reduce the computational complexity, the complex polynomial is mapped into a real-valued one by conformal mapping, and finally the DOAs can be obtained by finding the roots of the real polynomial. The method requires no peak searching and the eigenvalue decomposition and polynomial rooting are all carried out in the real domain, and it can obtain improved angle estimation performance with greatly reduced computational complexity. Simulation results verify the effectiveness of the proposed algorithm.