Performance Modeling of an LTE LAA and WiFi Coexistence System Using the LAA Category-4 LBT Procedure and 802.11e EDCA Mechanism

Abstract

This paper studies the performance modeling and analysis of an LAA and WiFi coexistence system using the LAA category-4 LBT procedure and 802.11e EDCA mechanism. Unlike existing work, this study takes into account transmission priorities and the GAP period problem in a coexistence system under an unsaturated condition. A 3-D Markov chain is first built to model an LAA category-4 LBT procedure in the coexistence system, taking into account transmission priorities and the GAP period problem, and a 3-D Markov chain is built to model an 802.11e EDCA procedure, taking into account transmission priorities. Based on the Markov models, theoretical models are further derived for analyzing the performance of the coexistence system in terms of normalized throughput and average channel access delay. The derived analytical models are justified through simulation results and the impacts of major system parameters on the performance of the coexistence system are investigated based on the derived performance models.