Analytical Modeling of Wi-Fi and LTE-LAA Coexistence: Throughput and Impact of Energy Detection Threshold

TL;DR

This paper develops an analytical model to evaluate Wi-Fi and LTE-LAA coexistence in unlicensed bands, analyzing how network parameters like energy detection thresholds affect throughput, validated through experiments.

Contribution

It introduces one of the first analytical frameworks for Wi-Fi and LTE-LAA coexistence, incorporating modifications to the Bianchi model and experimental validation.

Findings

Energy detection threshold significantly impacts coexistence performance.

The analytical model accurately predicts throughput in various scenarios.

Experimental validation confirms the model's reliability.

Abstract

With both small-cell LTE and Wi-Fi networks available as alternatives for deployment in unlicensed bands (notably 5 GHz), the investigation into their coexistence is a topic of active interest, primarily driven by industry groups. 3GPP has recently standardized LTE Licensed Assisted Access (LTE-LAA) that seeks to make LTE more co-existence friendly with Wi-Fi by incorporating similar sensing and back-off features. Nonetheless, the results presented by industry groups offer little consensus on important issues like respective network parameter settings that promote "fair access" as required by 3GPP. Answers to such key system deployment aspects, in turn, require credible analytical models, on which there has been little progress to date. Accordingly, in one of the first work of its kind, we develop a new framework for estimating the throughput of Wi-Fi and LTE-LAA in coexistence scenarios via suitable modifications to the celebrated Bianchi \cite{Bianchi} model. The impact of various network parameters such as energy detection (ED) threshold on Wi-Fi and LTE-LAA coexistence is explored as a byproduct and corroborated via a National Instrument (NI) experimental testbed that validates the results for LTE-LAA access priority class 1 and 3.