Performance Evaluation of LTE-LAA and Wifi Coexistence Based on Cat-4 Procedure

Abstract

In recent years, mobile data traffic has significantly increased and licensed bands have become more scared and congested. This occurs when the demand for digital connectivity has grown exponentially over the years as people today heavily rely on technology. For that reason, to enhance the existing LTE performance, a favorable, economically viable and promising initiative was introduced by implementing LTE in the unused spectrum. Licensed Assisted Access (LAA) for LTE has been proposed by the Third Generation Partnership Project (3GPP) for addressing user needs. Despite employing the Listen-Before-Talk (LBT) method, this proposed network has had issues in integration with other networks, WiFi. This is because of the various factors, including the window backoff size and sensing period length. The integration of LTE-LAA and WiFi networks employing the Category-4 (CAT-4) technique is evaluated in this study. Since it conducts similarly to the CSMA/CA protocol that is applied by end users of WiFi, the CAT-4 procedure is chosen. As a result, MATLAB was used in this study's evaluation to simulate the airtime performance for WiFi and LTE-LAA networks. Based on the findings, it was concluded that the performance of both networks during airtime is mostly influenced by the appropriate values of LTE sensing duration and the window backoff size. Hence, when both parameters are tuned to optimal, the best performance for coexistence between the two networks is guaranteed.