MIMO-DCSK通信系统在瑞利衰落信道下的误码性能分析

摘要

The transmission Bit Error Rate(BER) of Multiple-Input-Multiple-Output Differential Chaos Shift Keying(MIMO-DCSK) communication systems under Rayleigh fading channels are analyzed. Gaussian Approximation(GA) method based on the Central Limit Theory(CLT) is presented. The simulation results show that the consistency between GA BER curves and actual simulated curves enhances with an increasing spreading factor. Compared with DCSK, the BER performance of MIMO-DCSK is greatly improved by the increasing number of transmitting and receiving antennas. And the increase of the number of receiving antennas can get more gain than increasing transmitting antennas. With the increase of transmitting antennas, the non-orthogonality of the signals among different antennas leads to a deviation between GA BER curves and simulation curves, which will reduce after the spreading factor increasing.%对多输入多输出差分混沌相移键控(MIMO-DCSK)通信系统在瑞利衰落信道下的性能进行了分析，给出了基于中心极限定理的高斯近似误码率表达公式，并与计算机仿真数据进行比较。仿真结果表明：随着扩频因子的增大，高斯近似误码率曲线与实际仿真误码率曲线的一致性也随之增强；相比 DCSK系统，随着发送天线数量和接收天线数量的增加，MIMO-DCSK系统的误码性能有较大提升，且增加接收天线的数量可以比增加发送天线的数量获得更大的增益；随着发送天线数量的增多，不同天线间信号的非正交性导致理论误码率曲线与仿真曲线出现差别，在扩频因子增大后趋于一致。