多用户载波索引差分混沌移位键控通信系统及性能分析

Multi-User Carrier Index Differential Chaos Shift Keying Communication System and Performance Analysis

现有载波索引差分混沌移位键控(DCSK)通信系统较传统DCSK系统能耗更低且数据传输速率更高,但其无法应用于多用户通信环境。提出一种多用户载波索引差分混沌移位键控系统,为系统用户分配预定义的私有子载波发送混沌参考信号,所有用户共享剩余子载波发送数据信号以提高子载波利用率,结合公共子载波的索引值与DCSK系统共同传送用户的数据比特,并在加性高斯白噪声和多径Rayleigh衰落信道中计算得到系统的近似误码率。实验结果表明,与MU OFDM-DCSK、HCS-DCSK等多用户系统相比,该系统的误码率更低,在不占用过多带宽的情况下,具有更高的频谱效率。

Compared with the traditional Differential Chaos Shift Keying(DCSK)system,the existing Carrier Index DCSK(CI-DCSK)communication system has lower energy consumption and higher data transmission rate,but it can not be applied to multi-user communication environment.This paper presents a Multi-User Carrier Index DCSK(MU CI-DCSK)system.Predefined private subcarriers are allocated to the system users to send chaotic reference signals,so that all users can share the remaining subcarrier carrier to transmit data signals to improve the utilization of the subcarriers,simultaneously interpreting the data bits of users with the common subcarrier index and the DCSK system.Then the approximate Bit Error Rate(BER)of the system is calculated in the Additive White Gaussian Noise(AWGN)and multipath Rayleigh fading channels.Experimental results show that the BER of the system is lower than that of MU OFDM-DCSK,HCS-DCSK and other multiuser systems,and the system has higher spectral efficiency without occupying too much bandwidth.