摘要
针对互耦误差下多输入多输出(multiple input multiple output,MIMO)雷达的低仰角估计的问题,提出一种目标角度估计的自校准算法。首先分析了收发阵列同时存在互耦误差时的多径回波信号模型,然后利用均匀线阵互耦矩阵的特点对互耦误差下的阵列导向矢量进行变换,最后基于子空间原理推导出目标角度的搜索函数,同时给出多径衰减系数和收发阵列互耦矩阵的计算表达式。推导了各参数的任意无偏估计的Cramer-Rao界(Cramer-Rao bound,CRB)。算法在未知互耦矩阵和存在相干多径信号的情况下可直接进行参数估计,不需要辅助校准源和迭代处理。仿真结果分析了算法估计性能与信噪比、快拍数的关系并与CRB进行了比较。
A method for low elevation estimation in the presence of multipath effect and mutual coupling error for multiple input multiple output （MIMO） radar is proposed. Mutual coupling and multipath effect are taken into account for the signal model. Utilizing the characteristics of the mutual coupling matrix in uniform linear arrays, the steering vector can be transformed. Finally, based on the underlying basis for subspace-based method, the low elevation is obtained. More importantly the reflectance and the mutual coupling matrix can also be achieved simultaneously. Additionally, the Cramer-Rao bound （CRB） is derived. The proposed method can estimate these parameters in the presence of multipath effect without any previous calibration information as initialization. Simulation results illustrate the performance of the algorithm and comparison with the CRB.
出处
《系统工程与电子技术》
EI
CSCD
北大核心
2012年第2期270-275,共6页
Systems Engineering and Electronics
基金
国家自然科学基金(60901068)
长江学者和创新团队发展计划(IRT0645)资助课题
关键词
多输入多输出雷达
互耦误差
多径
低仰角估计
CRAMER-RAO界
multiple input multiple output （MIMO） radar
mutual coupling error
multipath
low elevationestimation
Cramer-Rao bound （CRB）
