In this letter, we investigate covert communication in relay networks with relay selection. We consider the scenario that while forwarding the source’s message, the selected relay opportunistically transmits its own message to the destination covertly. We derive the probability of detection error (PDE) and the average covert rate (ACR) in a closed form, based on which we analyse the effects of system parameters on the performance of the covert communication. Our analysis indicates that applying relay selection causes a decrease in the PDE, however, it can provide an ACR gain when the transmission rate of the source increases.

中文翻译：

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隐蔽通信与继电器选择

在这封信中，我们将研究具有中继选择功能的中继网络中的秘密通信。我们考虑这样一种情况，即在转发源消息时，所选中继机会会秘密地将其自己的消息传输到目标。我们以封闭形式导出检测错误的概率（PDE）和平均隐蔽率（ACR），在此基础上我们分析系统参数对隐蔽通信性能的影响。我们的分析表明，应用中继选择会导致PDE降低，但是，当源的传输速率增加时，它可以提供ACR增益。