联合优化方向图合成与频谱兼容的MIMO雷达波形设计

多发射-多接收雷达发射方向图合成是当前波形设计和合成问题的热点，其目的在于实现将发射能量聚焦在感兴趣的空域方向上。而在复杂的电磁环境中，还必须兼顾考虑在拥堵频段上的频谱兼容性和灵活性，避免影响邻近频段通信系统传输性能。该文提出算法设计MIMO雷达发射波形向目标空域聚焦能量的同时，避开拥堵频段的频率范围。即针对发射波形在空域、频域两类要求而联合优化。联合优化问题被建模为加权均方误差代价函数，优化问题是非凸非平滑的。在算法的每一步迭代优化中，首先更新当前步骤的匹配系数，再对均方误差代价函数进行放缩，构造替代函数；进而优化替代函数，得到较小代价函数值对应的波形。该文提出的迭代优化算法，具有接近理想的方向图合成性能与频谱塑形性能，且运算量小。仿真和数值结果证明了该方法的有效性。

MIMO Radar Transmit Waveform Design for Joint Optimizing Beampattern Synthesis and Spectral Compatibility

This paper investigates joint optimization of beampattern synthesis and spectral compatibility of multiple-input multiple-output (MIMO) radar transmit waveform under constant modulus constraint. In complex electromagnetic environments, it is necessary to consider the spectrum compatibility and flexibility in the congested frequency band to avoid poor transmission performance of the communication system in the adjacent frequency band. In this paper, the joint optimization problem is modeled as a weighted mean square error cost function constrained by constant modulus, which is non-convex and non-smooth. In each step of the iterative optimization algorithm, firstly update the matching coefficient of the current step and scale the cost function to construct a majorization function. Next, the majorization function is optimized to obtain a waveform correspond to a smaller cost function value. The performance of the proposed algorithm has a good performance on beampattern synthesis and spectrally compatibility, it also has a small amount of calculation. Simulation and numerical results prove the effectiveness of the proposed method.