基于OFDM的雷达通信一体化共波形设计

Common waveform design of radar communicationIntegration based on OFDM

摘要:

为了减小通信信息对一体化波形模糊函数的影响,以连续波信号为基础,提出了一种基于扩频的多OFDM符号调制的雷达通信一体化信号模型,并分别从波形以及雷达模糊函数的角度对其进行分析。通过对通信信息预扩频后采用OFDM调制的方法,可显著改善一体化信号的模糊函数性能,降低距离维旁瓣。理论分析表明,一体化信号的距离旁瓣由所用伪随机编码序列的自相关、互相关特性及调制的通信信息共同决定,为波形的性能改进提供了指导方向。仿真结果表明扩频因子、子载波数目、数据长度的不同取值对雷达通信一体化信号的距离维模糊函数的旁瓣的影响,为优化一体化信号的性能提供依据。设计的雷达通信一体化信号模型可有效改善对通信信息和多普勒频移的敏感性,满足雷达探测波形要求。

Abstract:

In order to reduce the influence of communication information on integrated waveform ambiguity function,it proposes an integrated signal model of radar communication based on spread spectrum modulation with multiple OFDM symbols and analyze it from the angle of waveform and radar ambiguity function respectively. By using the method of OFDM modulation in pre spread spectrum of communication information, the performance of ambiguity function of integrated signal can be significantly improved, and the range sidelobe can be reduced.Theoretical analysis shows that the range sidelobe of the integrated signal is determined by the autocorrelation, cross-correlation characteristics of the pseudo-random coded sequence and modulation communication information , which provides guidance for the performance improvement of the waveform. The simulation results show that the influence of different values of the spreading factor, the number of subcarriers, the length of the data on the radar communication integration signal range ambiguity function sidelobes, and provide the basis for the performance optimization of integrated signal. The design of radar integrated signal model can effectively improve the sensitivity of communication information and Doppler frequency shift to meet the radar detection waveform requirements.