基于功率域复用的低轨卫星多址技术及性能分析  

Power Domain Multiplexing Based Multiple Access and Performance Analysis in LEO Satellite Communication Systems

作　　者：李田 李国彦[1] 李辉[1] 侯睿 郝学坤 岳新伟 李刚[6] LI Tian;LI Guoyan;LI Hui;HOU Rui;HAO Xuekun;YUE Xinwei;LI Gang(The 54th Research Institute of CETC,Shijiazhuang 050081,China;Beijing University of Posts and Telecommunications,Beijing 100876,China;PMCEDD of CMC,Beijing 100034,China;The 50th Research Institute of China Electronics Technology Group Corporation,Shanghai 200331,China;Beijing Information Science and Technology University,Beijing 100101,China;Shijiazhuang Public Security Bureau,Shijiazhuang 050000,China)

机构地区：[1]中国电子科技集团公司第五十四研究所,河北石家庄050081 [2]北京邮电大学,北京100876 [3]军委装备发展部装备项目管理中心,北京100034 [4]中国电子科技集团公司第五十研究所,上海200331 [5]北京信息科技大学,北京100101 [6]石家庄市公安局技术侦察支队,河北石家庄050000

出　　处：《无线电通信技术》2020年第5期591-597,共7页Radio Communications Technology

基　　金：中国博士后科学基金资助项目(2019M661051);北京信息科技大学促进高校内涵发展项目(5211910924);北京信息科技大学师资补充与支持计划(5111911147)。

摘　　要：针对低轨卫星通信系统中转发器带宽资源紧缺问题,提出了基于功率域复用的多址传输方法。通过挖掘低轨卫星发射信号方向角对等效信道增益带来的影响,设计基于功率因子差异的多信号叠加编码方法,实现波束中心用户和波束边缘用户信息的共载波传输。为验证所设计方法的优势,推导了功率域复用方法和传统频分多址方法所能提供的遍历和速率的解析表达式,并进一步分析了两用户信道增益差异对该方法的性能增益影响。仿真结果证明了所推导的解析表达式的正确性,相对传统频分多址方法,该方法可提供更高的遍历和速率。In this paper,a power domain multiplexing(PDM)based multiple access is proposed to solve the problem of spectrum shortage in low Earth orbit satellite communication systems.By exploiting the difference of the equivalent downlink channel gains,signals for beam-center and beam-edge users can be transmitted simultaneously in the same resource block using superposition coding.Specifically,the performance of the beam-edge user can be enhanced by designing a reasonable power factor allocation strategy.To validate the advancement of the proposed method,analytical expressions for ergodic sum rates of the two users was derived.Furthermore,the impact of the channel gain gap between the two users on the system performance improvement was also analyzed.Simulation results confirm the correctness of the expressions and show that the PDM-based method outperforms the conventional frequency division multiple access scheme in terms of the ergodic sum rate.In addition,the conclusion that the performance advantage grows with the gap of the channel gains is derived.

关 键 词：低轨卫星通信 功率域复用 叠加编码 遍历和速率 性能增益 

分 类 号：TN927[电子电信—通信与信息系统]