云接入网(Cloud Radio Access Network,C-RAN)中有限带宽的前程链路无法有效应对高铁场景下乘客大量集中式的网络资源请求.针对这一不足,本文对C-RAN架构中的射频拉远头(Remote Radio Head,RRH)配置缓存设备使其具有存储转发资源的功能...云接入网(Cloud Radio Access Network,C-RAN)中有限带宽的前程链路无法有效应对高铁场景下乘客大量集中式的网络资源请求.针对这一不足,本文对C-RAN架构中的射频拉远头(Remote Radio Head,RRH)配置缓存设备使其具有存储转发资源的功能,利用列车运行信息可预知的先验条件,针对乘客数据通信提出基于缓存机制的预下载方案以提升网络系统的吞吐量.仿真结果表明,在前程链路拥挤情况下,基于缓存的预下载方案可明显提升资源的平均传输速率和高铁通信网络的吞吐量,进而提升了乘客的在途通信服务质量(Quality of Service,QoS).展开更多
The centralized radio access cellular network infrastructure based on centralized Super Base Station(CSBS) is a promising solution to reduce the high construction cost and energy consumption of conventional cellular n...The centralized radio access cellular network infrastructure based on centralized Super Base Station(CSBS) is a promising solution to reduce the high construction cost and energy consumption of conventional cellular networks. With CSBS, the computing resource for communication protocol processing could be managed flexibly according the protocol load to improve the resource efficiency. Since the protocol load changes frequently and may exceed the capacity of processors, load balancing is needed. However, existing load balancing mechanisms used in data centers cannot satisfy the real-time requirement of the communication protocol processing. Therefore, a new computing resource adjustment scheme is proposed for communication protocol processing in the CSBS architecture. First of all, the main principles of protocol processing resource adjustment is concluded, followed by the analysis on the processing resource outage probability that the computing resource becomes inadequate for protocol processing as load changes. Following the adjustment principles, the proposed scheme is designed to reduce the processing resource outage probability based onthe optimized connected graph which is constructed by the approximate Kruskal algorithm. Simulation re-sults show that compared with the conventional load balancing mechanisms, the proposed scheme can reduce the occurrence number of inadequate processing resource and the additional resource consumption of adjustment greatly.展开更多
为了更好适应下一代通信网络以内容为中心的特性,在云接入网络(Cloud Radio Access Network,Cloud-RAN)中考虑射频拉远头(Remote Radio Heads,RRHs)具备缓存功能也变得必要。本文考虑在Cloud-RAN中设计优化算法,并通过有效设计缓存方案...为了更好适应下一代通信网络以内容为中心的特性,在云接入网络(Cloud Radio Access Network,Cloud-RAN)中考虑射频拉远头(Remote Radio Heads,RRHs)具备缓存功能也变得必要。本文考虑在Cloud-RAN中设计优化算法,并通过有效设计缓存方案减少系统传输时延。基于混合式自动重传请求(hybrid automatic repeat request,HARQ)的重传机制,前程链路与下行链路频谱信道的正交性,系统采用马尔可夫链理论建立了最小化系统传输时延的优化问题。考虑只能通过递归方式得到优化目标函数表达式,头脑风暴优化(brain storm optimization,BSO)算法被引入解决非凸问题,仿真结果表明,该优化算法可以更有效地减少系统传输时延,满足未来通信需求。展开更多
文摘云接入网(Cloud Radio Access Network,C-RAN)中有限带宽的前程链路无法有效应对高铁场景下乘客大量集中式的网络资源请求.针对这一不足,本文对C-RAN架构中的射频拉远头(Remote Radio Head,RRH)配置缓存设备使其具有存储转发资源的功能,利用列车运行信息可预知的先验条件,针对乘客数据通信提出基于缓存机制的预下载方案以提升网络系统的吞吐量.仿真结果表明,在前程链路拥挤情况下,基于缓存的预下载方案可明显提升资源的平均传输速率和高铁通信网络的吞吐量,进而提升了乘客的在途通信服务质量(Quality of Service,QoS).
基金supported in part by the National Science Foundationof China under Grant number 61431001 the Beijing Talents Fund under Grant number 2015000021223ZK31
文摘The centralized radio access cellular network infrastructure based on centralized Super Base Station(CSBS) is a promising solution to reduce the high construction cost and energy consumption of conventional cellular networks. With CSBS, the computing resource for communication protocol processing could be managed flexibly according the protocol load to improve the resource efficiency. Since the protocol load changes frequently and may exceed the capacity of processors, load balancing is needed. However, existing load balancing mechanisms used in data centers cannot satisfy the real-time requirement of the communication protocol processing. Therefore, a new computing resource adjustment scheme is proposed for communication protocol processing in the CSBS architecture. First of all, the main principles of protocol processing resource adjustment is concluded, followed by the analysis on the processing resource outage probability that the computing resource becomes inadequate for protocol processing as load changes. Following the adjustment principles, the proposed scheme is designed to reduce the processing resource outage probability based onthe optimized connected graph which is constructed by the approximate Kruskal algorithm. Simulation re-sults show that compared with the conventional load balancing mechanisms, the proposed scheme can reduce the occurrence number of inadequate processing resource and the additional resource consumption of adjustment greatly.