基于非均匀子阵划分的MIMO雷达阵列设计研究

本文提出一种非均匀子阵划分的MIMO雷达阵列设计方法，其不但具有和均匀子阵划分的MIMO雷达（也称为相控阵-MIMO雷达）相同的优势—能同时获得相干处理增益和波形分集增益；并且，不同孔径的子阵使子波束的形成更加灵活；更大的子阵孔径给发射端提供了额外的自由度。 理论分析表明，与相控阵-MIMO雷达相比，采用常规波束形成，当干噪比比较低时，所提的非均匀子阵划分的MIMO雷达的输出信干噪比（SINR）更高。仿真实验也证明了上述理论分析的正确性，并表明所提的非均匀子阵的划分方法可以获得更低的副瓣电平。在最小方差无畸变响应波束形成下，零陷更深，输出SINR更高并且抗干扰能力更强。

MIMO radar array design based on unequal subarrays

The idea of dividing the transmitting array of MIMO radar into unequal subarrays was proposed in the paper. This kind of MIMO radar obtains the coherent processing gain and the waveform diversity gain which the MIMO radar with equal subarrays (called it phased-MIMO radar) enjoys. Furthermore, different sizes of subarrays form multiple beams; the greater apertures of subarrays provide more degree of freedom at the transmitting side. Theoretical analysis shows that compared with the phased-MIMO radar, the MIMO radar with unequal subarrays enjoys higher output signal-to-interference-plus-noise ratio (SINR) at low interference-to-noise ratios (INRs) by nonadaptive beamforming. Simulation results validate the correctness of the above theoretical analysis, and shows that the proposed MIMO radar with unequal subarrays can achieve lower sidelobe levels, deeper null steering, and higher output SINR by minimum variance distortionless response (MVDR), which is contributed to the its ability to reject interference combined with its robustness against sensor noise.