OFDM雷达通信共享信号距离旁瓣抑制研究

Range Side Lobe Suppression of Integrated Radar and Communication Signals Based on OFDM

在采用自适应调制技术的正交频分复用(OFDM)雷达通信一体化系统中,共享信号通常具有非矩形且变化的功率谱,这导致传统旁瓣抑制方法出现主旁瓣比降低及信噪比损失增加等问题。针对该情况,提出了一种新的OFDM共享信号距离旁瓣抑制方法,根据发射信号功率谱自适应设计幅度加权函数,将旁瓣抑制问题转化为优化问题求解。仿真结果表明,该方法在发射信号频谱变化甚至断续的情况下,都能有效抑制OFDM共享信号的距离旁瓣,且具有远小于常规方法的信噪比损失。

In the integrated radar and communication(RadCom)system which using adaptive modulation technology and orthogonal frequency division multiplexing(OFDM)signals,the RadCom signal usually has a non-rectangular and varying power spectrum,which leads to the deterioration of the traditional side lobe suppression methods,such as the reduction of the peak to side lobe ratio and the increase of SNR loss.To solve this problem,a new range side lobe suppression method for OFDM RadCom signals was proposed.In this method,an adaptive amplitude weighting function is designed according to the power spectrum of emission signals,and the side lobe suppression problem is transformed into an optimization problem.The simulation results show that the range side lobe of OFDM RadCom signal is effectively suppressed under the condition of the spectrum variation or even discontinuous of transmitted signal,and the signal-to-noise ratio loss of this method is much smaller than that of conventional methods.