摘要
基于一维混沌的调频(FM)信号的相空间结构性强,容易被截获,提出了基于二维Cat映射的调频信号。给出了高维混沌调频信号的信号模型,并将基于二维Cat映射的调频信号分别与一维Bernulli调频信号和线性调频(LFM)信号从不同角度进行详细比较。仿真结果表明,基于二维Cat映射的调频信号与Bernulli调频信号相比,在具有相似的自相关特性、功率谱特性和模糊函数特性的同时,相空间更复杂,具有更低的截获率;与LFM信号相比,具有更高的距离、速度分辨力,不存在距离速度耦合,脉压输出的距离旁瓣更低,但是对多普勒频移更敏感。对该信号的研究可以为对低截获率要求高、多普勒频移范围较小的场合提供参考。
Frequency modulated（ FM） radar signal based on 1D chaotic maps may be likely intercepted,because its phase space structure is strong.Therefore,FM signal based on 2D Cat map is proposed.The signal model is presented,and detailed comparison of FM signal based on 2D Cat map with FM signal based on 1D Bernulli map and linear frequency modulated（ LFM） signal is made.The simulation results show that,FM signal based on 2D Cat map has more complicated structure,lower probability of interception and similar performance in autocorrelation function,power spectrum and ambiguity function with FM signal based on 1D Bernulli map;compared with LFM signal,FM signal based on 2D Cat map has higher directivity and speed resolution,lower distance side-lobe after pulse compression and no range-velocity coupling problem,but it is more sensitive to Doppler frequency.The research can provide a reference for the occasion which has small Doppler frequency and high request for lower probability of interception.
出处
《科学技术与工程》
北大核心
2015年第3期116-119,共4页
Science Technology and Engineering
