Spatial and Time Domain Model for LAA/Wi-Fi Coexistence

In Release 13 of the 3rd Generation Partnership Project standard, the deployment of long-term evolution (LTE)/LTE-advanced to the unlicensed spectrum called licensed-assisted access (LAA) was introduced to satisfy the high demand of traffic data with a new type of services mostly multimedia streams. The unlicensed spectrum is a shared resource between different radio access terminals such as Wi-Fi and radar system, and listen before talk (LBT) in LTE side makes this coexistence possible. In this letter, we propose a new framework to model and evaluate the performance of LAA/Wi-Fi coexistence based on marked Poisson point process (MPPP) and Markov chain model. The proposed model captures the back-off procedure in the spatial and time domain to provide a more realistic analysis of the channel busy probability and the signal to interference plus noise ratio coverage probability. Numerical results show the validity of the proposed model with the overestimation of the LAA and Wi-Fi nodes density in MPPP model.