基于线性调频时宽的MIMO雷达正交波形设计

MIMO Radar Orthogonal Waveform Set Design Based on Chirp Durations

线性调频(LFM)信号是一种被广泛应用的大时宽带宽积信号,利用LFM信号的多样性可设计多输入多输出(MIMO)雷达的正交波形。该文针对现有波形相关函数存在的问题,以理论分析为基础,提出一种基于LFM时宽的发射波形,并给出了一种相应的正交波形设计方法。该方法以峰值旁瓣电平为准则,利用序列二次规划对各子脉冲LFM信号的时宽进行优化设计。仿真结果表明,与现有方法相比,所设计波形具有较低的自相关旁瓣电平和互相关电平。此外,通过数值实验分析了相关性能随波形个数及子脉冲个数的变化关系。

Due to the large time-bandwidth product, Linear Frequency Modulation （LFM） signals are widely used, and their diversity can be applied to orthogonal waveform set design for MIMO radar. To solve the problems of the correlation functions of the existing waveforms, detailed analysis is made, a new waveform based on chirp durations is proposed, and the orthogonal waveform set design method is given subsequently. Peak sidelobe level is calculated for the cost function, the chirp durations of subpulses are optimized by Sequential Quadratic Programming （SQP）. Simulation results show that the designed waveforms have lower autocorrelation sidelobe level and crosscorrelation level compared with the present method. In addition, relationships among autocorrelation sidelobe level, crosscorrelation level and the size of orthogonal waveforms are studied via numerical experiments.