询问反馈策略下的门限截断机会波束系统  

A Threshold Truncated Opportunistic Beamforming System under Inquiring Feedback Strategy

作　　者：苏佳 张曙[1] 

机构地区：[1]哈尔滨工程大学信息与通信工程学院,哈尔滨150001

出　　处：《西安交通大学学报》2010年第8期72-77,共6页Journal of Xi'an Jiaotong University

基　　金：国家自然科学基金资助项目(60875020);哈尔滨市优秀学科带头人基金资助项目(2009RFXXG034)

摘　　要：针对目前多用户多输入单输出机会波束中存在的用户数和反馈量过多的问题,提出了一种询问反馈策略下的门限截断机会波束系统——询问截断机会波束.以吞吐量最大化为原则设定截断门限,用户只有被基站询问且接收信干噪比大于系统截断门限时才进行反馈,一旦基站接收到反馈信息就停止对相应波束的询问,并分配给相应用户,重复此过程直到完成所有波束的分配.若某一发射波束在询问所有用户后仍未有反馈,则截断此波束发射.相对于传统机会波束系统,询问截断机会波束能够优选发射波束,降低反馈量.在瑞利衰落信道中对系统性能进行分析和仿真,并与传统机会波束比较,结果表明合理设置截断门限能将反馈量降低到1%以下,并将用户较少时的吞吐量提高了约1.2b/(s·Hz).In order to solve the problem that there are too many users and feedbacks in multi-user multiple-input single-output opportunistic beamforming（OBF）system,a threshold truncated OBF under inquiring feedback strategy（TTOBF-IF）is proposed.A truncating threshold is set based on maximizing the throughput.The user will feed back only when inquired and the ratio of the receiving signal to interference and noise is larger than the pre-set truncating threshold.Once the base station receives feedback information,it will stop inquiring the corresponding beam,and allocate the beam to the corresponding user.Repeat the process until the allocation of beams is completed.If a transmitting beam has no feedback after inquiring all users,it will be truncated.The TTOBF-IF can optimally select transmitting beams and reduce feedbacks.Analysis and simulations in the Rayleigh fading channel and comparisons with the OBF show that through setting threshold reasonably,TTOBF-IF reduces the feedbacks to 1%,and increases the throughput by 1.2b/（s·Hz）when the number of users is less.

关 键 词：截断门限 系统容量 机会波束 多输入单输出 

分 类 号：TN929.5[电子电信—通信与信息系统]