The covert capacity is characterized for a non-coherent fast Rayleigh-fading wireless channel, in which a legitimate user wishes to communicate reliably with a legitimate receiver while escaping detection from a warden. It is shown that the covert capacity is achieved with an amplitude-constrained input distribution that consists of a finite number of mass points including one at zero and numerically tractable bounds are provided. It is also conjectured that distributions with two mass points in fixed locations are optimal.

中文翻译：

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非相干瑞利衰落信道的隐蔽容量

隐蔽容量的特点是非相干快速瑞利衰落无线信道，其中合法用户希望在逃避管理员检测的同时与合法接收器进行可靠通信。结果表明，隐蔽容量是通过振幅受限的输入分布实现的，该分布由有限数量的质点组成，其中一个质点为零，并且提供了数值上易于处理的边界。还推测在固定位置具有两个质点的分布是最优的。