【作者】 吕星哉；

【导师】 朱近康；

【作者基本信息】 中国科学技术大学 ， 通信与信息系统， 2009， 博士

【摘要】 本文研究了多基站协同通信系统的结构和无线资源管理,目标是提出基于现有结构的,低复杂度,高性能,高可实现性的多基站协同资源分配算法.主要研究了新型的有序分布系统结构,多基站功率控制算法和多小区多用户调度算法。首先,本文根据传统蜂窝小区的缺点和无线信号的传播特性,提出了可兼容现有系统的新型的有序分布系统结构。新系统在原本有序的结构中引入了分布式的处理,通过将多个基站覆盖的区域分为单一覆盖区和交叉覆盖区,来充分利用各个基站的资源并抑制共道干扰。本文研究了正三角形小区,正六边形小区等结构,对每种结构进行了系统容量分析,并提出了不同结构下的频率配置和参数设计的方法。将这种新型结构的遍历容量和中断容量与传统蜂窝结构以及全分布式系统做了比较,发现新结构通过引入基站间的宏分集协作和频率复用,可以有效地抑制干扰,提升系统容量。功率控制在多小区系统中是重要的抑制干扰的手段。本文提出了在传统小区或单一覆盖区下基于Stackelberg博弈的功率控制算法。通过将多小区的功率控制问题建模为领导者-追随者模型来综合考虑用户及网络的效用,并利用制订统一全局价格的方法来抑制并剔除信道条件较差的用户,以优化整个系统的容量。然后证明在大规模干扰理想网络内,该博弈会收敛到唯一的最优均衡点,并提出了一个价格更新函数来动态调整整个网络内的发送功率价格。仿真结果表明该算法在大规模系统中有很好的性能。本文还研究了交叉覆盖区和宏分集模式下的功率控制。首先针对单个交叉覆盖区或宏分集小区的情况,在各个小区使用正交空时编码作为宏分集方案时,提出了一种各基站间的功率分配方案。若最小化遍历成对符号差错率上界,其功率分配结果等效于按信道大尺度衰落信息进行注水算法分配。为了降低功率分配的复杂度,通过对最优化问题的近似,提出了一种低复杂度的功率分配算法。该算法为每个分布式基站分配一个权重,根据该权重按比例进行功率分配。在大多数情况下该低复杂度算法可以达到与注水算法相近的性能。在网络中有多个交叉覆盖区或者是宏分集小区时,提出了一种新的主从协同功率控制算法。该算法把为移动台服务的基站分为主基站和从基站,各从基站以主基站分配的功率为参考值分配功率,并可采用低复杂度和开销的分布式形式实现。与现有的分布式系统中功控算法相比,新算法可以显著地提高整个系统的容量。此外,还提出了一种可以在扁平化网络中使用的主从基站通信系统机制。在研究功率控制问题的基础上,本文进一步提出了多小区多用户中的干扰匹配调度机制.其目标是在信干比平衡的功率控制算法下最大化系统的容量。该算法考虑每个用户的信道条件和发送引起的共道干扰,在同一个时刻调度匹配的用户。本文证明这种干扰匹配算法在任何小区数及用户数下都可以最优化系统容量的下界。且干扰匹配调度是一种低复杂度的算法,并可以全分布式的方式实现。仿真结果说明其性能很接近最优算法的性能。同时该算法与先前文献提出的轮转调度和功率匹配调度算法相比有很大的性能增益,当系统范围很大的时候,这种增益尤为明显。更多还原

【Abstract】 This thesis focuses on the architecture and radio resource management of multiple base stations cooperative communication systems.The target is to propose low-complexity,high-performance, broadly applicable radio resource algorithms for multiple base stations cooperative systems.This research mainly includes the novel architecture called orderly distributed communication system,the power control algorithms for multiple base stations, and the multiuser scheduling policy for multicell circumstance.First,in consideration of the drawbacks of the traditional cellular system and the properties of radio propagation,this thesis proposes a novel wireless network architecture called orderly distributed communication system,which is compatible with the extant system. The new architecture introduces the distributed process into a strictly orderly system.It fully utilizes the resource of each base station by dividing the coverage area into uni-covered regions and cross-covered regions.This thesis studies on the regular triangular cell and regular hexangular cell.For each architecture,the system capacity is analyzed,and the rules of choosing the system parameters are given.Comparing the ergodic and outage throughput of the novel architecture with those of traditional cellular systems and fully distributed systems,it can be found that the new architecture can effectively suppress the interference and improve the capacity by introducing both macro diversity and frequency reuse between multiple base stations.Power control is an effective approach to suppress the interference in cellular network. This thesis proposes a power control method which is based on the Stackelberg game for the traditional cellular systems or uni-covered regions.It improves the system capacity by modeling the power control problem as a leader-follower game,and establishing a global price to eliminate the users with bad channel condition.This thesis proves that this game converges to a unique equilibrium in a large-scale interference ideal network,and proposes a price update function to adjust the price of the whole network.Numerical results show that this algorithm performs well especially in a large-scale system.This thesis also studies the power control method for cross-covered regions and macro diversity mode.First,for one cell or cross-covered region case,when the orthogonal spacetime coding is used to obtain the macro diversity gain,this thesis proposes a power allocation scheme among different base stations.To minimize the upper bound of the ergodic pair-wise symbol error rate is equivalent to perform water-filling against the large-scale fading.To reduce the complexity,a novel power allocation method is proposed by approximating the original problem.This method assigns a weight to each base station,and allocates power proportional to these weights.In most situations,the weight-based method can achieve almost the same performance as water-filling.Second,for the multiple cells or cross-covered regions case,this thesis proposes a novel primary-subsidiary cooperative power control method.This algorithm divides the service base stations as primary base stations and subsidiary base stations.The subsidiary base station adjusts its transmit power according to the transmit power of the primary base station.The new algorithm can be implemented in a distributed way,and significantly improve the system capacity while compared with the extant power control method for fully distributed systems.Moreover,a novel primary-subsidiary cooperative communication policy for a flat network is proposed.Based on the study of power control,this thesis further proposes an interference matched multiuser scheduling policy in multicell circumstance.The target is to maximize the system throughput under signal to interference balanced power control method.This policy takes the channel conditions and potential interference of each user into consideration,and schedules matched users in each slot.This thesis proves that the interference matched algorithm optimizes the lower bound of the system capacity irrespective of the cell number and the user number.Moreover,the new algorithm has an extremely low complexity,and can be implemented in a fully distributed way.Simulation results show there is only a very narrow performance gap betweenthe new method and the optimal scheduling.And over the extant round robin scheduling and power matched scheduling,the novel method achieves a great performance gain,especially in a large-scale system.更多还原