This work considers a layered coding approach for efficient transmission of data over a wireless block fading channel without transmitter channel state information (CSI), which is connected to a limited capacity reliable link, known as the bottleneck channel. Two main approaches are considered, the first is an oblivious approach, where the sampled noisy observations are compressed and transmitted over the bottleneck channel without having any knowledge of the original information codebook. The second approach is a non-oblivious decode-forward (DF) relay where the sampled noisy data is decoded, and whatever is successfully decoded is reliably transmitted over the bottleneck channel. The bottleneck channel from relay to destination has a fixed capacity $C$ . We examine also the case where the channel capacity can dynamically change due to variable loads on the backhaul link. The broadcast approach is analyzed for cases that only the relay knows the available capacity for next block, and for the case that neither source nor relay know the capacity per block, only its capacity distribution. Fortunately, it is possible to analytically describe in closed form expressions, the optimal continuous layering power distribution which maximizes the average achievable rate. Numerical results demonstrate the achievable broadcast rates.

中文翻译：

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信息瓶颈通道的广播方法

这项工作考虑了一种分层编码方法，用于在没有发射机信道状态信息（CSI）的无线块衰落信道上有效传输数据，该信道连接到有限容量的可靠链路（称为瓶颈信道）。考虑了两种主要方法，第一种是遗忘方法，其中在不了解原始信息码本的情况下，将采样的噪声观测值压缩并通过瓶颈通道进行传输。第二种方法是非遗忘解码转发（DF）中继，其中对采样的有噪数据进行解码，并且成功解码的任何内容都会在瓶颈通道上可靠地传输。从中继到目的地的瓶颈通道具有固定的容量 $ C $ 。我们还研究了由于回程链路上的可变负载而导致信道容量可能动态变化的情况。对于仅中继站知道下一个块的可用容量的情况，以及对于源和中继站都不知道每个块的容量的情况，仅广播广播块的容量分布，将对广播方法进行分析。幸运的是，可以用封闭形式分析地描述最佳连续分层功率分布，该分布使平均可达到的速率最大化。数值结果证明了可以达到的广播速率。