一种OFDM雷达通信共享信号优化设计方法

Optimal Design Method of OFDM Radar Communication Shared Signal

摘要:

多载波体制的雷达通信共享信号主要采用正交频分复用(orthogonal frequency division multiplexing, OFDM)技术进行设计。基于OFDM 的雷达通信共享信号的循环前缀具有消除码间串扰、维持各个子载波正交的重要作用。但循环前缀会使信号模糊函数产生“伪峰”,降低能量利用率,影响雷达性能。针对该问题,提出了一种利用空白保护间隔的方法,在不影响通信质量的前提下消除“伪峰”,同时有效降低模糊函数的峰值旁瓣比。在此基础上进一步利用互补P4码和OFDM 相结合的方式生成新的雷达通信共享信号。经仿真验证,相比于16阶正交幅度调制(16QAM)与OFDM 相结合生成的16QAM-OFDM 信号,新的雷达通信共享信号距离模糊图的峰值旁瓣比降低了1.871dB。

Abstract:

The radar communication shared signal of multi-carrier system is mainlydesigned by orthogonal frequency division multiplexing (OFDM). The cyclic prefix in theradar communication shared signal based on OFDM plays an important role in eliminatingintersymbol crosstalk and maintaining the orthogonality of each subcarrier, However, cyclicprefix causes "pseudo peak of signal ambiguity function, reduces energy utilization andaffects radar performance. To so ve the problem .a method of using blank guard interva isproposed to eliminate the "pseudo peak" without affecting the communication quality,and toeffectively reduce the peak sidelobe ratio (PSLR) of ambiguity function, On the basis of themethod,a new radar communication shared signal is generated by the combination oicomplementary P4 code and OFDM. The simulation results show that compared with theshared signal based on 16 guadrature amplitude modulation and OFDM (16QAM-OFDM).the peak sidelobe ratio of range ambiguity map of the new radar communication shared signalis reduced by 1.871 dB.