We consider a block fading additive white Gaussian noise (AWGN) channel with perfect channel state information (CSI) at the transmitter (CSIT) and the receiver (CSIR). For a given codeword length and non-vanishing average probability of error, we obtain lower and upper bounds on the maximum transmission rate. First, we derive bounds when the transmitter has a time varying peak power constraint imposed by an energy harvesting device; such devices power many modern wireless devices. Next, using the same techniques we obtain bounds for the canonical peak and average power constraint cases. The bounds characterize the finite blocklength back-off from the channel capacity, which is in turn achieved by water-filling power allocation across time. Finally, we derive bounds on the moderate deviations constant for the block fading model. We compare the bounds numerically to bring out the efficacy of our results.

中文翻译：

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能量收集和固定功率约束下块衰落信道的细化渐近性

我们考虑在发射机 (CSIT) 和接收机 (CSIR) 具有完美信道状态信息 (CSI) 的块衰落加性高斯白噪声 (AWGN) 信道。对于给定的码字长度和非零平均错误概率，我们获得最大传输速率的下限和上限。首先，当发射器具有由能量收集设备施加的随时间变化的峰值功率约束时，我们推导出界限；此类设备为许多现代无线设备提供动力。接下来，我们使用相同的技术获得规范峰值和平均功率约束情况的界限。边界表征了信道容量的有限块长度回退，而这又是通过跨时间的注水功率分配来实现的。最后，我们推导出块衰落模型的中等偏差常数的界限。