Abstract. Microwave staring correlated imaging (MSCI) is a staring high-resolution microwave imaging technique, employing the temporal–spatial stochastic radiation field (TSSRF). The imaging capability of MSCI depends on the spatial correlation of the TSSRF, which is equivalent to the incoherence of the sensing matrix in discrete form. A waveform design method for MSCI using multifrequency signals to reduce the spatial correlation of the TSSRF is proposed. The amplitude of each frequency component in the multifrequency signals serves as the design variable. Considering the power and the amplitude constraints in the practical radar system, we first form the waveform design as a constrained optimization problem. Then, it is reformulated as a nonsmooth unconstrained optimization problem by the penalty function method. With the smoothing approximation, the reformulated problem is solved by alternating minimization. Numerical experiments show that the proposed method can decrease the spatial correlation of the TSSRF and improve the imaging performance of MSCI as a result.

中文翻译：

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基于空间相关最小化的微波凝视相关成像随机辐射场优化

摘要。微波凝视相关成像 (MSCI) 是一种凝视高分辨率微波成像技术，采用时空随机辐射场 (TSSRF)。MSCI 的成像能力取决于 TSSRF 的空间相关性，这相当于离散形式的传感矩阵的不相干性。提出了一种利用多频信号降低TSSRF空间相关性的MSCI波形设计方法。多频信号中每个频率分量的幅度用作设计变量。考虑到实际雷达系统中的功率和幅度约束，我们首先将波形设计形成为一个约束优化问题。然后，通过惩罚函数方法将其重新表述为非光滑无约束优化问题。使用平滑近似，重新制定的问题通过交替最小化来解决。数值实验表明，所提出的方法可以降低TSSRF的空间相关性，从而提高MSCI的成像性能。