Feedback-based coding algorithms for broadcast erasure channels with degraded message sets
Feedback-based coding algorithms for broadcast erasure channels with degraded message sets
复制标题
具有降级消息集的广播擦除信道的基于反馈的编码算法
DOI：
10.1109/netcod.2012.6261893
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发表时间：
2012
期刊：
影响因子：
--
通讯作者：
C. Fragouli
中科院分区：
文献类型：
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作者：
M. Gatzianas;S. S. Bidokhti;C. Fragouli
我们考虑单跳广播数据包擦除通道（BPEC），其具有降级的消息集和所有接收器定期提供的瞬时反馈，并证明[1]中针对多个单播会话提出的基于虚拟队列的算法的主要原理仍然可以应用于这种设置并导致容量实现算法。具体来说，我们提出了一类通用算法，并直观地描述了其原理和导致其效率的属性。然后，我们将此类算法应用于 BPEC 通道的三个示例（具有不同数量的用户和 2 或 3 个降级消息集），并表明可实现的吞吐量区域与已知容量外界匹配，假设通过单独的公共通道提供反馈。如果反馈通道不是公共的，所有用户仍然可以解码他们的消息，尽管会产生一些开销，这会导致可实现的吞吐量与外部边界相差 O(N/L)，其中 L 是数据包长度。这些算法的操作不需要任何信道统计知识。
We consider single-hop broadcast packet erasure channels (BPEC) with degraded message sets and instantaneous feedback regularly available from all receivers, and demonstrate that the main principles of the virtual-queue-based algorithms in [1], which were proposed for multiple unicast sessions, can still be applied to this setting and lead to capacity-achieving algorithms. Specifically, we propose a generic class of algorithms and intuitively describe its rationale and properties that result in its efficiency. We then apply this class of algorithms to three examples of BPEC channels (with different numbers of users and 2 or 3 degraded message sets) and show that the achievable throughput region matches a known capacity outer bound, assuming feedback availability through a separate public channel. If the feedback channel is not public, all users can still decode their messages, albeit at some overhead which results in an achievable throughput that differs from the outer bound by O(N/L), where L is the packet length. These algorithms do not require any prior knowledge of channel statistics for their operation.