基于改进式特征值二次对角加载的信源数估计方法

Source Number Estimation Method Based on Improved Quadratic Diagonal Eigenvalue Loading

针对应用阵列天线进行信号接收时的信源数估计问题,提出一种基于改进式特征值二次对角加载的信源数估计方法。对天线阵列观测信号协方差矩阵进行特征值分解;对特征值进行一次对角加载,对角加载量取所有特征值的几何平均值,将原始特征值与对角加载值相加,取代原始特征值;重新计算特征值对角加载量,并进行二次对角加载,使加载后的特征值满足噪声特征值的最大最小值之比不超过2的条件,在此基础上,使用信息论准则类方法和随机矩阵理论类方法实现信源数的估计。仿真实验结果表明,该信源数估计方法具有可行性。

To solve the problem of estimating the number of sources when receiving signals with array antennas,a method of estimating the number of sources based on improved quadratic diagonal loading of eigenvalues is proposed.The method comprises the following steps of:carrying out eigenvalue decomposition on an antenna array observation signal covariance matrix;carrying out primary diagonal loading on an eigenvalue,wherein the diagonal loading quantity is taken as the geometric mean value of all eigenvalues,and adding an original eigenvalue and a diagonal loading value to replace the original eigenvalue;For the eigenvalues after the first diagonal loading,the diagonal loading amount of the eigenvalues is recalculated,and the secondary diagonal loading is carried out on the eigenvalues after the first diagonal loading,so that the loaded eigenvalues meet the condition that the ratio of the maximum to the minimum of the noise eigenvalues does not exceed 2.On this basis,the information theory criterion method and the random matrix theory method are used to estimate the number of information sources.The simulation results show that the proposed method is feasible.