Joint Cache-Channel Coding over Erasure Broadcast Channels

Roy Timo; Michele Wigger

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arXiv · 1505.01016

Joint Cache-Channel Coding over Erasure Broadcast Channels

Roy Timo·Michele Wigger

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Abstract

We consider a cache-aided communications system in which a transmitter communicates with many receivers over an erasure broadcast channel. The system serves as a basic model for communicating on-demand content during periods of high network congestion, where some content can be pre-placed in local caches near the receivers. We formulate the cache-aided communications problem as a joint cache-channel coding problem, and characterise some information-theoretic tradeoffs between reliable communications rates and cache sizes. We show that if the receivers experience different channel qualities, then using unequal cache sizes and joint cache-channel coding improves system efficiency.

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Roy Timo, Michele Wigger. 2015-05-05. Joint Cache-Channel Coding over Erasure Broadcast Channels. https://arxiv.org/abs/1505.01016

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