A Network-Coded Diversity Protocol for Collision Recovery in Slotted ALOHA Networks

TL;DR

This paper introduces a network-coded collision recovery protocol for slotted ALOHA that enhances throughput and energy efficiency by leveraging physical layer network coding and addressing practical synchronization issues.

Contribution

It presents a novel collision recovery scheme using physical layer network coding over Galois Fields, improving throughput and energy efficiency in slotted ALOHA networks.

Findings

Higher maximum throughput compared to previous schemes

High energy efficiency with optimized transmission probability

Remarkable normalized throughput performance

Abstract

We propose a collision recovery scheme for symbol-synchronous slotted ALOHA (SA) based on physical layer network coding over extended Galois Fields. Information is extracted from colliding bursts allowing to achieve higher maximum throughput with respect to previously proposed collision recovery schemes. An energy analysis is also performed, and it is shown that, by adjusting the transmission probability, high energy efficiency can be achieved. The paper also addresses several practical aspects, namely frequency, phase, and amplitude estimation, as well as partial symbol asynchronism. A performance evaluation is carried out using the proposed algorithms, revealing remarkable performance in terms of normalized throughput.