In modern communication systems with feedback, there are increasingly more scenarios where the transmitter has much less power than the receiver (e.g., medical implant devices), which we refer to as noise-asymmetric channels. For such channels, the feedback link is of higher quality than the forward link. However, feedback schemes for cellular communications, such as hybrid ARQ, do not fully utilize the high-quality feedback link. To this end, we introduce Compressed Error Hybrid ARQ, a generalization of hybrid ARQ tailored for noise-asymmetric channels; the receiver sends its estimated message to the transmitter, and the transmitter harmoniously switches between hybrid ARQ and compressed error retransmission. We show that our proposed method significantly improves reliability, latency, and spectral efficiency compared to the conventional hybrid ARQ in various practical scenarios where the transmitter is resource-constrained.

翻译：在现代带反馈的通信系统中，发射机功率远低于接收机（如医疗植入设备）的场景日益增多，我们将其称为噪声非对称信道。在此类信道中，反馈链路质量优于前向链路。然而，蜂窝通信中诸如混合自动重传等反馈方案并未充分利用高质量反馈链路。为此，我们提出压缩误差混合自动重传——一种专为噪声非对称信道设计的混合自动重传泛化方案：接收机将其估计消息发送给发射机，发射机则在混合自动重传与压缩误差重传间进行协调切换。理论分析与仿真表明，在发射机资源受限的多种实际场景中，与传统混合自动重传相比，所提方法可显著提升可靠性、降低时延并提高频谱效率。