双基地MIMO雷达相干源角度估计方法

Method for angle estimation of coherent sources in bistatic MIMO radar

针对双基地多输入多输出(MIMO)雷达的相干源角度估计问题,分别在空间高斯白噪声和空间高斯色噪声背景下提出基于降维波达方向(DOA)矩阵的角度估计方法.首先对MIMO雷达相干目标的回波进行解相干处理;然后分别在两种噪声背景下构造DOA矩阵,并利用其与信号子空间的关系得到降维DOA矩阵,有效降低了原DOA矩阵法的运算量.之后利用降维DOA矩阵的特征参数与待估参数间的特定关系实现目标离开方向(DOD)和波达方向(DOA)的联合估计.该方法无需二维谱峰搜索,在两种不同噪声背景下均能有效估计相干源的二维角度并实现自动配对,且在接收阵列为非等距线阵的条件下仍具有适用性.仿真实验验证了该方法的有效性.

Aiming at the angle estimation for coherent sources in bistatic MIMO radar,two methods based on the dimension reduction DOA matrix are presented in spatially white noise and in spatially colored noise,respectively.Firstly,the virtual array data of multi-target echoes in MIMO receivers is uncorrelated.Secondly,DOA matrices in different noise environments are constructed.The dimension reduction DOA matrices which reduce the computational complex are obtained by the relationship between signal subspace and DOA matrices.Finally,the joint estimation of DOD and DOA can be obtained by the corresponding relationships between the eigenvalue or eigenvector and the estimated parameters.The proposed methods do not need the multi-dimensional peak search,and can estimate the parameters of coherent sources without pairing in both two noise circumstances.Moreover,it is applicable to receiving arrays without an invariance structure.Numerical results are presented to demonstrate the effectiveness of the method advanced.