将空间谱估计算法应用于毫米波热辐射阵列接收系统对目标进行超分辨率探测, 需要解决目标热辐射信号弱及阵列误差使性能下降这两个主要问题.为此, 建立了低信噪比阵列误差模型, 该模型综合考虑了通道幅相误差对信源和通道噪声的影响, 推导出由它们所造成的阵列接收数据自相关矩阵的特征值扰动范围和信号特征向量空间误差距离.利用该模型提出了一种通道幅相误差校正算法, 使得高分辨率的空间谱估计算法能够很好地应用于毫米波热辐射阵列接收系统, 并通过实验验证了新模型及校正算法的正确性和有效性.

In order to apply spatial spectrum estimation to millimeter-wave thermal radiation array receiving system for detecting targets with superior resolution, it is needed to solve two key problems which are weaknesses of thermal signals’ energy emitted from targets and the decline of performance caused by array errors. To solve these problems, an array error model with low signal-noise ratio(SNR) was presented. In this model, the influences of amplitude and phase errors on signal source and channel noise were considered, and the perturbation range of the eigenvalues and the error distance of the signal eigenvector space of the autocorrelation matrix received by arrays were derived. Then the calibration algorithm for amplitude and phase errors based on the model was proposed, which could make the spatial spectrum estimation with high resolution be used in millimeter-wave radiation array system effectively. The effectiveness and correctness of the model are verified by the experiments.