Finite Length Analysis of Irregular Repetition Slotted ALOHA in the Waterfall Region

TL;DR

This paper introduces a finite length analysis method for irregular repetition slotted ALOHA (IRSA) that accurately predicts its performance in high packet loss scenarios, using a model based on low-density parity-check codes.

Contribution

It provides a novel finite length analysis tailored to the collision channel, enabling precise performance estimation of IRSA in the waterfall region.

Findings

Accurately estimates packet loss probability in the waterfall region

Validates analysis with Monte Carlo simulations

Maps IRSA decoding to LDPC code interference cancellation

Abstract

A finite length analysis is introduced for irregular repetition slotted ALOHA (IRSA) that enables to accurately estimate its performance in the moderate-to-high packet loss probability regime, i.e., in the so-called waterfall region. The analysis is tailored to the collision channel model, which enables mapping the description of the successive interference cancellation process onto the iterative erasure decoding of low-density parity-check codes. The analysis provides accurate estimates of the packet loss probability of IRSA in the waterfall region as demonstrated by Monte Carlo simulations.