无信号内干扰的正交多用户降噪DCSK混沌通信系统  

Orthogonal multiuser noise reduction DCSK communication system with no intra-signal interferences

作　　者：张刚[1] 王星宇 贺利芳[1] ZHANG Gang;WANG Xingyu;HE Lifang(School of Communications and Information Enginerring,Chongqing University of Posts and Telecommunications,Chongqing 400065,China)

机构地区：[1]重庆邮电大学通信与信息工程学院,重庆400065

出　　处：《南京邮电大学学报（自然科学版）》2022年第4期7-15,共9页Journal of Nanjing University of Posts and Telecommunications：Natural Science Edition

基　　金：国家自然科学基金(61771085,61371164);重庆市教育委员会科研项目(KJQN201900601,KJ1600407)资助项目。

摘　　要：为进一步提高正交多用户差分混沌键控(Multiuser Orthogonal Differential Chaos Shift Keying, OMU-DCSK)系统的传输速率和误码率性能,提出一种无信号内干扰的正交多用户降噪差分混沌键控通信系统。在发送端采用一种新型的移位正交混沌信号发生器用以产生四路正交的混沌信号,在一个时隙内用这四路正交的混沌信号分别乘Walsh码用以发送4N个用户的信息比特。同时在发送端将信号复制P次之后,在接收端引入滑动平均滤波器对接收信号进行平均,从而降低噪声的方差,使得系统的误码率性能得到了进一步的提升。推导了该系统在多径瑞利衰落信道以及加性高斯白噪声信道下的误码率公式,并进行了仿真实验,与理论推导值对比。仿真结果表明,该系统的误码率性能以及传输速率有了较为明显的提升,有极大的理论与应用价值。In order to improve the transmission rate and the bit error rate(BER) performance of the orthogonal multiuser differential chaos shift keying(OMU-DCSK) system, we propose an orthogonal multiuser noise reduction DCSK communication system without internal signal interferences. At the transmitter, a new shift orthogonal chaotic signal generator is used to generate four orthogonal chaotic signals. In a single time slot, each of the four orthogonal chaotic signals is multiplied by the Walsh code. Thus the information bits of each user can be sent. Meanwhile, a moving average filter is introduced to average the received signal after the signal is copied twice at the transmitter. Thus the variance of noise can be reduced and the BER performance of the system can be improved. The BER formulas of the system are derived in the multipath Rayleigh fading channel and the additive Gaussian white noise channel, and the simulation results are compared with the theoretical values. The simulation results show that the BER performance and the transmission rate of the system have been significantly improved, and the model has great theoretical and application value.

关 键 词：混沌通信 差分混沌键控 无信号内干扰 降噪 

分 类 号：TN911.3[电子电信—通信与信息系统]