On the Achievable Rates of Pairwise Multiway Relay Channels

TL;DR

This paper analyzes how user transmission order affects the maximum achievable rates in pairwise multiway relay channels, identifying optimal orderings and demonstrating their performance advantages at high SNR levels.

Contribution

It introduces a graphical model for pairwise MWRCs and derives optimal user orderings to maximize common and sum rates, providing insights into rate performance.

Findings

Optimal orderings maximize common and sum rates.

Performance gap diminishes at high SNR.

Simulation results validate theoretical findings.

Abstract

In this paper, we study the effect of users' transmission ordering on the common rate and sum rate of pairwise multiway relay channels (MWRCs) with functional-decode-forward strategy. To this end, we first develop a graphical model for the data transmission in a pairwise MWRC. Using this model, we then find the optimal orderings that achieve the maximum common rate and sum rate of the system. The achieved maximum common and sum rate are also found. Moreover, we show that the performance gap between optimal orderings and a random ordering vanishes when SNR increases. Computer simulations are presented for better illustration of the results.