新型正交多载波降噪差分混沌键控通信系统  

Novel quadrature multicarrier noise reduction differential chaos shift keying system

作　　者：张刚[1] 许可蓉 贺利芳[1] ZHANG Gang;XU Kerong;HE Lifang(School of Communication and Information Engineering,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：《华中科技大学学报（自然科学版）》2022年第3期55-61,共7页Journal of Huazhong University of Science and Technology(Natural Science Edition)

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

摘　　要：针对多载波差分混沌键控(MC-DCSK)传输速率低和误码性能差的问题,提出了一种新型正交多载波降噪差分混沌键控(NQMC-NRDCSK)系统.系统发送端利用开关使奇数帧和偶数帧共享一个参考信号,并用不同频率及相位正交的载波来携带参考信号和经沃尔什码调制后的用户信息,在接收端引入滑动平均滤波器来降低信道噪声对系统的干扰,并通过分配沃尔什码序列识别相应的用户信道再进行相关运算,以解调出对应的信息比特.推导了系统在多径瑞利衰落信道(RFC)和加性高斯白噪声(AWGN)信道下的理论误码率公式,并进行了仿真.结果表明:该系统的误码性能相对于MC-DCSK系统有明显地提升,且其传输速率和能量效率也很大程度上得到了提高.Aiming at the problems of low transmission rate and poor bit error performance in multi-carrier differential chaos shift keying(MC-DCSK),a novel quadrature multi-carrier noise reduction differential chaos shift keying(NQMC-NRDCSK) system was proposed. At the transmitter,the system made odd frame and even frames share a reference signal by using a switch,and bear reference signals and user information modulated by Walsh codes through carriers with different frequencies and quadrature phases.The receiver reduced the interference of channel noise to the system by introducing a moving average filter,and the corresponding Walsh code sequence was assigned to identify the corresponding user channel,and then perform correlation operation to demodulate the users’ information bits.The theoretical bit error rate expression of the system in multi-path Rayleigh fading channel(RFC) and additive white Gaussian noise(AWGN) channel were derived and verified by simulation.Simulation results show that the system is obviously improved compared with the multi-carrier DCSK system,and its transmission rate and energy efficiency are also raised in a great extent.

关 键 词：差分混沌移位键控 多载波 沃尔什码 滑动平均滤波器 传输速率 比特误码率 

分 类 号：TN911.3[电子电信—通信与信息系统]