We investigate the impact of fading correlation on the performance of the doubly dirty fading multiple access channel (MAC) with non-causally known side information at transmitters. Using Copula theory, we derive closed-form expressions for the outage probability (OP) and the coverage region under positive/negative dependence conditions. We show that a positive dependence structure between the fading channel coefficients is beneficial for the system performance, as it improves the OP and extends the coverage region compared to the case of independent fading. Conversely, a negative dependence structure has a detrimental effect on both performance metrics.

中文翻译：

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相关性在双脏衰落 MAC 与发射机边信息中的作用

我们研究了衰落相关性对双脏衰落多址信道 (MAC) 性能的影响，在发射机上具有非因果已知的辅助信息。使用 Copula 理论，我们推导出正/负相关条件下中断概率 (OP) 和覆盖区域的封闭形式表达式。我们表明，衰落信道系数之间的正相关结构有利于系统性能，因为与独立衰落的情况相比，它提高了 OP 并扩展了覆盖区域。相反，负依赖结构对两个性能指标都有不利影响。