摘要
针对传统差分混沌移位键控传输速率低并且传输多用户信息时比特误码率较高的缺点,提出一种改进型正交多用户降噪差分混沌键控通信系统。系统发送端产生的混沌序列经过复制后作为信息承载信号,通过不同的延时分别携带经沃尔什码调制的多用户信息,信号在接收端经过滑动平均滤波器后与自身进行相关运算,以解调出原始信息比特。在瑞利衰落信道下推导了系统的理论比特误码率公式,并进行了蒙特卡罗仿真。分析与仿真结果表明,该系统通过对接收信号的平均运算降低了噪声项方差,系统误码性能得以提高,并且其传输速率相比于差分混沌移位键控系统有所提升,有效地改善了多用户差分混沌移位键控系统的误码性能。
Aiming at the shortcomings of a low transmission rate in traditional Differential Chaos Shift Keying(DCSK)and a high bite error rate when transmitting multi-user information,an improved orthogonal multi-user noise reduction differential chaotic keying(OMU-NRDCSK)is proposed.The chaotic sequence generated at the sending end of the system is used as an information bearing signal after being duplicated,the multi-users’information modulated by the Walsh codes are transmitted respectively through different delays.At the receiver,after passing through the moving average filter,the received signals are correlated with themselves to demodulate the initial information signals.The bit error rate formula for the system under the Rayleigh fading channel is derived and Monte Carlo simulation is carried out.Analytical and simulation results show that the OMU-NRDCSK system reduces the noise term variance by averaging the received signals and improves the bit error performance,with its transmission rate improved compared to the DCSK system,which effectively improves the bit error performance of the multi-user DCSK system.
作者
张刚
刘金惠
张鹏
ZHANG Gang;LIU Jinhui;ZHANG Peng(School of Communication and Information Engineering,Chongqing University of Posts andTelecommunications,Chongqing 400065,China;Academic Affairs Office,Chongqing University of Posts andTelecommunications,Chongqing 400065,China)
出处
《西安电子科技大学学报》
EI
CAS
CSCD
北大核心
2020年第4期1-9,共9页
Journal of Xidian University
基金
国家自然科学基金(61771085)
重庆市教育委员会科研项目(KJ1600407,KJQN201900601)。