Abstract：Traditional meter-wave radar usually suffers from the problem of Beam Split (BS) and Radar Blind Area (RBA) in the situation of low-grazing angle. To alleviate this difficulty, a Frequency Diverse Subaperturing Multiple-Input Multiple-Output (FDS-MIMO) radar is proposed and a theoretical framework for the analytical investigation of multipath characteristics is presented. The specular and perturbational multipath model is built, along with closed-form expression of the joint transmit-receive beampattern gain. Moreover, a notional concept of Multipath Mitigation Area (MMA) is defined together with the corresponding boundary conditions, and the Low Observability Rate (LOR) is defined as a performance benchmarkan to evaluate the FDS-MIMO radar beam overage capability. Next, the FDS-MIMO radar low-altitude beam coverage performance is optimized according to the soutions of the boundary conditions. Both theoretical analysis and numerical results demonstrate the advantages of FDS-MIMO radar over the conventional phased-MIMO radar in terms of low altitude beam coverage performance, and the BS and RBA of meter-wave radar is decreased by ultilizing the range-dependent beampattern.
李星星,王党卫,马晓岩. 多径条件下米波频分MIMO雷达波束性能及优化方法[J]. 电子与信息学报, 2018, 40(8): 1787-1794.
LI Xingxing, WANG, Dangwei, MA Xiaoyan. Beam Performance and Optimization Method for Meter-wave Frequency Diverse MIMO Radar in Multipath Scenario. JEIT, 2018, 40(8): 1787-1794.
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