MIMO雷达方向图与稀疏频率波形联合设计

MIMO Radar Beampattern and Sparse Frequency Waveform Design

发射方向图设计与波形优化是MIMO雷达领域的热点,随着研究的深入越来越需要考虑包括频谱特性在内的雷达系统工作环境特性。针对采用传统波形容易产生互相干扰的频谱拥挤情况,本文提出了一种MIMO雷达方向图与稀疏频率波形联合设计方法。一方面保证了将能量集中辐射到所感兴趣的区域上的探测性能,另一方面由得到的稀疏频率波形可以避免MIMO雷达系统与其他同频工作设备互相干扰。该方法首先根据MIMO雷达方向图与波形矩阵的关系,列出具有稀疏频率约束与恒模约束的目标函数式;然后通过从期望方向图到自相关矩阵,再到恒模稀疏频率波形的步骤,应用循环算法求解目标函数;最后所得结果波形的方向图接近期望方向图,同时结果波形具有稀疏频率特性和良好的自相关特性。仿真结果验证了文中方法的有效性。

Design of beampattern and waveforms is attracting more interest in the field of MIMO radar system, and more working condition should be considered, such as the crowded spectrum. When continuous band is divided into several pieces, sparse frequency radar waveforms play an important role due to the special pattern of the sparse spectrum. In this paper, the idea of the joint design of the MIMO radar beampattern and the sparse frequency waveforms is proposed. On one hand, it ensures the detection performance of the energy concentrated radiation to the area of interest. On the other hand, sparse frequency waveform can avoid the interference between the radar system and other equipment working in the same frequency band. Given an ideal beampattern, we first formulate the optimization problem of obtaining the covariance matrix and then design the realizable beampattern with considering the both constant modulus and sparse frequency waveforms, where a cyclic algorithm is applied to solve these problems. The result with the joint design of the beampattern and wave- forms by our proposed method is close to the ideal beampattern. Furthermore, the obtained waveforms have sparse frequen- cy characteristics and good auto-correlation properties. The simulation results verify the effectiveness of this method.