工程科学学报
工程科學學報
공정과학학보
Journal of University of Science and Technology Beijing
2015年
8期
1098-1104
,共7页
肖楠%梁俊%刘玉磊%冉淏丹%朱巍%陈刘伟
肖楠%樑俊%劉玉磊%冉淏丹%硃巍%陳劉偉
초남%량준%류옥뢰%염호단%주외%진류위
卫星通信%认知无线电%功率控制%延迟%算法
衛星通信%認知無線電%功率控製%延遲%算法
위성통신%인지무선전%공솔공제%연지%산법
satellite communication%cognitive radio%power allocation%delay%algorithms
针对卫星通信网频谱资源利用率低下的问题,以信道有效容量最大化为优化目标,提出了一种支持时延约束的卫星Underlay认知无线网络功率控制与优化算法。首先根据网络拓扑结构建立了功率干扰模型,通过引入时域信道相关系数,推导了完全与非完全信道环境下基于时延约束的认知用户有效容量优化目标函数,并利用Lagrange方法求解得到不同场景下认知用户的最佳功率调整策略,简化了功率控制优化过程,最后通过实验仿真分析了影响认知用户信道有效容量的因素。结果表明,该算法能够根据业务时延约束条件和信道衰落特性变化动态调整认知用户的最佳发送功率,与等功率分配算法相比认知用户的信道有效容量得到了明显提高。
針對衛星通信網頻譜資源利用率低下的問題,以信道有效容量最大化為優化目標,提齣瞭一種支持時延約束的衛星Underlay認知無線網絡功率控製與優化算法。首先根據網絡拓撲結構建立瞭功率榦擾模型,通過引入時域信道相關繫數,推導瞭完全與非完全信道環境下基于時延約束的認知用戶有效容量優化目標函數,併利用Lagrange方法求解得到不同場景下認知用戶的最佳功率調整策略,簡化瞭功率控製優化過程,最後通過實驗倣真分析瞭影響認知用戶信道有效容量的因素。結果錶明,該算法能夠根據業務時延約束條件和信道衰落特性變化動態調整認知用戶的最佳髮送功率,與等功率分配算法相比認知用戶的信道有效容量得到瞭明顯提高。
침대위성통신망빈보자원이용솔저하적문제,이신도유효용량최대화위우화목표,제출료일충지지시연약속적위성Underlay인지무선망락공솔공제여우화산법。수선근거망락탁복결구건립료공솔간우모형,통과인입시역신도상관계수,추도료완전여비완전신도배경하기우시연약속적인지용호유효용량우화목표함수,병이용Lagrange방법구해득도불동장경하인지용호적최가공솔조정책략,간화료공솔공제우화과정,최후통과실험방진분석료영향인지용호신도유효용량적인소。결과표명,해산법능구근거업무시연약속조건화신도쇠락특성변화동태조정인지용호적최가발송공솔,여등공솔분배산법상비인지용호적신도유효용량득도료명현제고。
A power allocation algorithm supporting delay constrains which maximizes the channel effective capacity of secondary users for satellite “Underlay” cognitive radio networks is proposed to improve the spectrum utilization of a satellite communication system. A power interference model is established based on the topology of satellite cognitive radio networks first, and then the object functions of effective capacity are derived both in perfect and imperfect channel state information environments. The Lagrange method is used to obtain the optimized transmitting power of secondary users by introducing the time-domain channel correlation coefficient. Optimized power adjusting strategies under different scenes are discussed while the power allocating and optimizing process is simpli-fied. Factors which affect the effective capacity of secondary users are analyzed by simulation. The results indicate that the proposed power allocation algorithm can adjust the transmitting power of secondary users according to delay constrains with channel fading char-acteristics, and the channel effective capacity of secondary users is improved obviously compared to the traditional equal power alloca-tion policy.