Performance of orthogonal STBC-MIMO with variable-power adaptive modulation and delayed feedback in Nakagami fading channels  

作　　者：YU XiangBin CHEN XiaoMin BI GuangGuo RUI Yun 

机构地区：[1]College of Information Science and Technology, Nanjing University of Aeronautics and Astronautics [2]National Mobile Communications Research Laboratory, Southeast University [3]Shanghai Advanced Research Institute,Chinese Academic of Science

出　　处：《Science China(Information Sciences)》2013年第10期81-90,共10页中国科学（信息科学）（英文版）

基　　金：supported in part by Doctoral Fund of Ministry of Education of China(Grant No.20093218120021);National Natural Science Foundation of China(Grant No.61172077);Fundamental Research Funds for the Central Universities(Grant Nos.NS2012075,NZ2012012);National High Technology Research and Development Program of China(Grant No.2011AA01A105);Shanghai Committee of Science and Technology(Grant Nos.10DZ1500700,11DZ1500500);National Key Project of China(Grant No.2009ZX03003-006-03)

摘　　要：A variable-power （VP） adaptive modulation （AM） scheme with space-time block code （STBC） is developed in MIMO systems, and the corresponding performance is investigated in Nakagami fading channels. The optimum switching thresholds are derived so that the spectrum efficiency （SE） under an average power and a target bit error rate （BER） constraint is maximized. By the switching thresholds, average BER and SE are further derived. As a result, closed-form expressions are obtained. Besides, the exact and approximate BER expressions of VP AM and constant-power （CP） AM systems with delayed feedback are respectively derived. Simulation results show that the theoretical SE and BER can match the corresponding simulation well. The results indicate that VP-AM with STBC provide higher spectrum efficiency than the CP counterparts, and has slighter bite error rate performance degradation when the normalized delay is less than 0.01.A variable-power （VP） adaptive modulation （AM） scheme with space-time block code （STBC） is developed in MIMO systems, and the corresponding performance is investigated in Nakagami fading channels. The optimum switching thresholds are derived so that the spectrum efficiency （SE） under an average power and a target bit error rate （BER） constraint is maximized. By the switching thresholds, average BER and SE are further derived. As a result, closed-form expressions are obtained. Besides, the exact and approximate BER expressions of VP AM and constant-power （CP） AM systems with delayed feedback are respectively derived. Simulation results show that the theoretical SE and BER can match the corresponding simulation well. The results indicate that VP-AM with STBC provide higher spectrum efficiency than the CP counterparts, and has slighter bite error rate performance degradation when the normalized delay is less than 0.01.

关 键 词：orthogonal space-time coding adaptive modulation variable power delayed feedback Nakagamifading 

分 类 号：TN911.5[电子电信—通信与信息系统]