摘要
MIMO雷达中传统正交频分线性调频(OFD-LFM)波形的空域合成信号存在较高的自相关栅瓣。为了解决这一问题,本文在OFD-LFM波形上调制相位编码序列,构造新的正交频分线性调频相位编码(OFD-LFM-PC)波形以消除空域合成信号自相关栅瓣。由于相位编码的调制,使得OFD-LFM-PC波形空域合成信号的自相关栅瓣消除但整体旁瓣水平有所升高,同时,发射功率方向图非全向。为此,基于OFD-LFM-PC波形的时域特性和空域特性分析,本文建立了空时特性优化模型,对调制的相位编码矩阵和载波频率编码序列进行联合优化,并提出了一种嵌套遗传算法的粒子群算法求解该优化问题。仿真结果表明,所优化设计的OFD-LFM-PC波形能够保证发射功率方向图的全向性,并且空域合成信号具有良好的自相关性能。
High gating sidelobes exist in the autocorrelation function of the spatial synthesized orthogonal frequency division-linear frequency modulation(OFD-LFM)waveforms in multiple input multiple output(MIMO)radar.To solve this problem,the phase coded sequences are modulated on the OFD-LFM waveform to construct a new orthogonal frequency division-linear frequency modulation-phase coded(OFD-LFM-PC)waveform to eliminate the autocorrelation grating lobes of the spatial synthesized signal in this paper.Due to the phase modulation,the gating sidelobes of the spatial synthesized OFD-LFM-PC signal are eliminated but the overall sidelobe level is increased,meanwhile,the transmit power pattern is no longer omnidirectional.Therefore,based on the temporal and spatial analysis of the OFD-LFM-PC waveforms,a space-time joint optimization model is established;the phase coded matrix and the carrier frequency coded sequence are jointly optimized;and a particle swarm algorithm nested genetic algorithm is proposed to solve this problem.Simulation results show that the optimized OFD-LFM-PC waveform can obtain the omnidirectional transmit power pattern and ensure that the spatial synthesized signal has good autocorrelation performance.
作者
洪升
董延焘
艾煜
赵志欣
HONG Sheng;DONG Yantao;AI Yu;ZHAO Zhixin(School of Information Engineering, Nanchang University, Nanchang 330031, China)
出处
《雷达科学与技术》
北大核心
2020年第3期313-320,326,共9页
Radar Science and Technology
基金
国家自然科学基金(No.61661032,61461030)
中国博士后科学基金(No.2017M622102)
江西省博士后科研项目(No.2017KY36)
江西省自然科学基金(No.20161BAB212038,20181BAB202002)
南昌大学研究生创新专项资金(No.CX2018159)。
