In this paper, a chaotic communication system based on the combination of Improved–Differential chaos-shift keying (IDCSK) scheme and 2×2 MIMO technique (2T2R), namely 2T2R-IDCSK, is investigated. We point out that there are differences in correlation characteristics between the conventional and time-reversed chaotic sequences. From this aspect, bit-error-rate (BER) performance of the system over an additive white Gaussian noise (AWGN) channel is analyzed taking into account the correlation effect of time-reversed chaotic sequences. BER expressions are verified by Monte-Carlo simulation. The obtained results prove that the 2T2R-IDCSK system performs worse under the correlation effect, however still dramatically outperforms the conventional 2×2 MIMO-DCSK system.

中文翻译：

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时间反转混沌序列对2T2R-IDCSK系统性能的影响

本文提出了一种基于改进差分混沌键控 (IDCSK) 方案和2×2研究了MIMO技术（2T2R），即2T2R-IDCSK。我们指出，常规混沌序列和时间反转混沌序列之间的相关特征存在差异。从这个方面，考虑时间反转混沌序列的相关效应，分析了系统在加性高斯白噪声（AWGN）信道上的误码率（BER）性能。BER 表达式通过 Monte-Carlo 模拟进行验证。所得结果证明2T2R-IDCSK系统在相关效应下表现较差，但仍显着优于传统2×2MIMO-DCSK 系统。