On degrees of freedom of the cellular network

来源 :Science China(Information Sciences) | 被引量 : 0次 | 上传用户:rual7007
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (e.g., base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of interference alignment, we are able to exactly characterize the sum degrees of freedom (DoF) of the network when the channel coefficients are timeor frequency-varying, which equals KM K+min(M,K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there also exists the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprising result. In this paper, we consider the capacity limits of the cellular network by modeling it as consisting of two mutually interfering multiple access channels with multiple antennas at each receiver (eg, base station). By developing a tight outerbound as well as an achievable scheme which exploits the idea of ​​interference alignment, we are able to exactly characterize the sum degree of freedom (DoF) of the network when the channel coefficients are time frequency frequency-varying, which equals KM K + min (M, K) (where M and K denote the number of receiver antennas and number of users in per cell, respectively) per cell. From the DoF result, it can be observed that in addition to the multi-user gain which has been reported for the network with single-antenna BSs, there is also the multi-antenna gain in the cellular network. In particular, when the number of users is large, we can nearly achieve the interference-free DoF of a cellular network with multiple-antenna BSs, which is a somewhat surprisingin g result.
其他文献
经典的重铬酸钾法测定铁,是将试样溶解后用氯化亚锡把Fe还原为Fe,为了反应完全,氯化亚锡要适当过量,而过量的氯化亚锡除去时用的是氯化汞,这就是汞法测铁.由于该方法使用的时
在一些高校的"分析化学实验"课中,常以HCl-NHCl体系中各组分的测定作为强酸-弱酸混合酸分析的例子,或必做,或选做,或为设计实验.由于NH的酸性很弱(C
有机化学的发展提供了近千万种有机化合物及其各种类型的反应与相应的理论,有机化学课程内容极其丰富,但授课学时有限(应用化学专业80学时).面对要求高、内容多、学时有限的现
学院以编撰和使用具有新的编排特点的、更适于讲课及学生理解的笔记体的教材为契机,在课堂上与学生充分讨论"有机化学"知识,同时介绍相关的实验,使学生认识到理论和实践的距
会议
"有机化学"是化学学科的4大基础课之一,它相对于其他3门基础课而言,与人类的日常生活、工农业生产、环境保护、国防建设关系更为密切.是化学各专业以及农学、医学、药学、生
会议
同分异构(Isomerism)这个名词出现于19世纪30年代,在有机化学中是一个普遍现象和基本问题.可当时的人们尚未提出价键理论,对碳的正四面体构型等立体化学问题也不清楚,更无构
会议
高质量的教师队伍是培养创新型人才的核心,课堂教学环节是培养创新型人才的关键,实验实践教学是培养创新型人才的重要手段. 在创新教育的尝试中,笔者深切体会到创新教育的
"有机化学"是化学化工、生物、环境和材料等专业的一门基础必修课程,它论述有机化合物的结构与其性能的关系及反应机理和应用.有机化合物数量庞大,同分异构现象普遍存在,它们
会议
"有机化学"是医学院校的一门重要的基础课.自1988年以来,复旦大学化学系先后为上海地区原上海医科大学、上海第二医科大学、上海中医大学和第二军医大学等医科大学的医学类相
会议
<正> 当我接受编辑部的采访房屋建筑班的平常任务,同装修工班长娜塔丽娅·科辛娜相识时,奇迹在我身上发生了。我找到了自己的创作道路,找到了多年的,很可能是一辈子的爱好。探索内心世界娜塔丽娅·科辛娜是一个中年、劳累的妇女,有着一双长年忧伤,象是蒙上灰色灰尘,圣象画般的眼睛。她身上什么东西使我感到惊讶呢?是的,她工作好,她不是单纯地“赶任务”,而是以满腔的爱和极大的兴趣在装饰着自己的住宅。虽然她的工作成绩,已经构成了写作“材料”。但我没有立即离开,这位班长身上象是有什么东西抓住了我,不让我走开。