License Assisted Access-WiFi Coexistence with TXOP Backoff for LTE in Unlicensed Band  

作　　者：Salman Saadat Da Chen Kai Luo Mingjie Feng Tao Jiang 

机构地区：[1]School of Electronics Information and Communications, Huazhong University of Science and Technology, Wuhan 430074, China

出　　处：《China Communications》2017年第3期1-14,共14页中国通信（英文版）

基　　金：supported in part by Joint Specialized Research Fund for the Doctoral Program of Higher Education (SRFDP) and Research Grants Council Earmarked Research Grants (RGC ERG) with Grant 20130142140002;National Science Foundation of China with Grants 61531011 and 61471163;Major Program of National Natural Science Foundation of Hubei in China with Grant 2016CFA009

摘　　要：License assisted access(LAA) was proposed as a solution to the challenge of satisfying high throughput requirement in cellular network with limited licensed band. LAA uses long term evolution(LTE) carrier aggregation technique to combine licensed and unlicensed bands, specifically 5 GHz Wi Fi band, in order to achieve high data rates. However, LAA has several critical concerns for services provision on 5 GHz unlicensed band. In this article, an overview of the techniques concerning the coexistence of LTE and Wi Fi on the same unlicensed band is presented. We first present several general approaches including power control of LTE evolved Node B(e NB), carrier selection, LTE duty cycling, self clear to send(CTS) and request to send/CTS(RTS/CTS), and listen before talk(LBT). Then, we focus on LBT techniques for LAA-Wi Fi coexistence and discuss how LBT based coexistence solutions can dynamically respond to the variations in network load and ensure fair coexistence in a distributed manner. Based on the LBT mechanism, we also present a fairness-aware LAA-WiF i coexisting scheme with TXOP(transmitted in a single transmission opportunity) backoff for LAA e NB. Finally, the performances of various LBT solutions for LAA-Wi Fi coexistence are evaluated using Markov chain analytical model.License assisted access（LAA） was proposed as a solution to the challenge of satisfying high throughput requirement in cellular network with limited licensed band. LAA uses long term evolution（LTE） carrier aggregation technique to combine licensed and unlicensed bands, specifically 5 GHz Wi Fi band, in order to achieve high data rates. However, LAA has several critical concerns for services provision on 5 GHz unlicensed band. In this article, an overview of the techniques concerning the coexistence of LTE and Wi Fi on the same unlicensed band is presented. We first present several general approaches including power control of LTE evolved Node B（e NB）, carrier selection, LTE duty cycling, self clear to send（CTS） and request to send/CTS（RTS/CTS）, and listen before talk（LBT）. Then, we focus on LBT techniques for LAA-Wi Fi coexistence and discuss how LBT based coexistence solutions can dynamically respond to the variations in network load and ensure fair coexistence in a distributed manner. Based on the LBT mechanism, we also present a fairness-aware LAA-WiF i coexisting scheme with TXOP（transmitted in a single transmission opportunity） backoff for LAA e NB. Finally, the performances of various LBT solutions for LAA-Wi Fi coexistence are evaluated using Markov chain analytical model.

关 键 词：WiFi unlicensed band LTE coexistence license assisted access listen before talk 

分 类 号：TN929.5[电子电信—通信与信息系统]