Low-Complexity Coding Techniques for Cloud Radio Access Networks

Nadim Ghaddar; Lele Wang

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arXiv · 2408.14565

Low-Complexity Coding Techniques for Cloud Radio Access Networks

Nadim Ghaddar·Lele Wang

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Abstract

The problem of coding for the uplink and downlink of cloud radio access networks (C-RAN's) with $K$ users and $L$ relays is considered. It is shown that low-complexity coding schemes that achieve any point in the rate-fronthaul region of joint coding and compression can be constructed starting from at most $4(K+L)-2$ point-to-point codes designed for symmetric channels. This reduces the seemingly hard task of constructing good codes for C-RAN's to the much better understood task of finding good codes for single-user channels. To show this result, an equivalence between the achievable rate-fronthaul regions of joint coding and successive coding is established. Then, rate-splitting and quantization-splitting techniques are used to show that the task of achieving a rate-fronthaul point in the joint coding region can be simplified to that of achieving a corner point in a higher-dimensional C-RAN problem. As a by-product, some interesting properties of the rate-fronthaul region of joint decoding for uplink C-RAN's are also derived.

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Nadim Ghaddar, Lele Wang. 2024-08-26. Low-Complexity Coding Techniques for Cloud Radio Access Networks. https://arxiv.org/abs/2408.14565

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