Performance Analysis of LTE-LAA Network

3rd generation partnership project (3GPP) has developed 5-GHz unlicensed band long term evolution (LTE), referred to as licensed-assisted access (LAA). LAA adopts listen-before-talk (LBT) operation, resembling Wi-Fi's carrier sense multiple access with collision avoidance (CSMA/CA), to enable collision avoidance capability. However, the frame structure overhead of each LAA downlink burst varies with the ending time of each preceding LBT operation. Given that, the existing analytic models of Wi-Fi cannot be used to evaluate the performance of LAA due to the fact that, unlike Wi-Fi, LAA frame structure overhead varies with the ending time of the preceding LBT operation. In this letter, we propose a novel Markov chain-based analytic model to cope with the variation of the LAA frame structure overhead. Comparison between analysis and simulation results shows that the difference between them is merely 0.2% on average, demonstrating the accuracy of the proposed model.