Low-Latency Data Sharing in Erasure Multi-Way Relay Channels

TL;DR

This paper introduces low-latency, low-complexity fountain coding schemes for erasure multi-way relay channels, improving data sharing efficiency without feedback channels and approaching theoretical rate bounds.

Contribution

Proposes novel fountain coding-based data sharing schemes for EMWRC, introduces the end-to-end erasure rate metric, and analyzes their performance analytically and via simulations.

Findings

Proposed schemes outperform one-way relaying for small user numbers and erasure rates.

Achievable rates of proposed schemes are close to the theoretical upper bound.

EEER effectively predicts scheme performance and overhead.

Abstract

We consider an erasure multi-way relay channel (EMWRC) in which several users share their data through a relay over erasure links. Assuming no feedback channel between the users and the relay, we first identify the challenges for designing a data sharing scheme over an EMWRC. Then, to overcome these challenges, we propose practical low-latency and low-complexity data sharing schemes based on fountain coding. Later, we introduce the notion of end-to-end erasure rate (EEER) and analytically derive it for the proposed schemes. EEER is then used to calculate the achievable rate and transmission overhead of the proposed schemes. Using EEER and computer simulations, the achievable rates and transmission overhead of our proposed schemes are compared with the ones of one-way relaying. This comparison implies that when the number of users and the channel erasure rates are not large, our proposed schemes outperform one-way relaying. We also find an upper bound on the achievable rates of EMWRC and observe that depending on the number of users and channel erasure rates, our proposed solutions can perform very close to this bound.