The high-speed railway and high-way networks are now expanding at a phenomenal speed in Chinaand in many other parts of the world. The related broadband wireless communication over high-speed trains and highway vehicl...The high-speed railway and high-way networks are now expanding at a phenomenal speed in Chinaand in many other parts of the world. The related broadband wireless communication over high-speed trains and highway vehicles is a very challenging task due to hostile transmission channel conditions. The demand for such services is growing rapidly, following the proliferation of laptop/tablet computers and smart phones. This motivates the research on wireless communications in the high mobility environments.展开更多
With the increasing utilization of High-Speed Trains （HSTs）, the need for a reliable and high-bandwidth Internet access under high-speed mobility scenarios has become more demanding. In static, walking, and low mobi...With the increasing utilization of High-Speed Trains （HSTs）, the need for a reliable and high-bandwidth Internet access under high-speed mobility scenarios has become more demanding. In static, walking, and low mobility environments, TCP/IP （transmission control protocol/Internet protocol） can work well. However, TCP/IP cannot work well in high-speed scenarios because of reliability and handoff delay problems. This is mainly because the mobile node is required to maintain the connection to the corresponding node when it handovers to another access point node. In this paper, we propose a named data networking wireless mesh network architecture for HST wireless communication （NDN-Mesh-T）, which combines the advantages of Wireless Mesh Networks （WMNs） and NDN architectures. We attempt to solve the reliability and handoff delay problems to enable high bandwidth and low latency in Internet access in HST scenarios. To further improve reliability and bandwidth utilization, we propose a Direction-Aware Forwarding （DAF） strategy to forward Interest packet along the direction of the running train. The simulation results show that the proposed scheme can significantly reduce the packet loss rate by up to 51% compared to TCP/IP network architecture. Moreover, the proposed mechanism can reduce the network load, handoff delay, and data redundancy.展开更多
目前,国内高速铁路使用基于全球铁路移动通信系统(Global System for Mobile Communications-Railway,GSM-R)的双向无线通信系统,实现列车与地面之间的安全信息传输。然而,无线通信存在传输延迟和丢包,严重时会影响运行效率,因此需要研...目前,国内高速铁路使用基于全球铁路移动通信系统(Global System for Mobile Communications-Railway,GSM-R)的双向无线通信系统,实现列车与地面之间的安全信息传输。然而,无线通信存在传输延迟和丢包,严重时会影响运行效率,因此需要研究GSM-R系统服务质量(Quality of Service,QoS)参数,以满足实时性和可用性需求。选取传输延时作为待优化的GSM-R无线通信系统QoS参数,定量分析端到端传输延迟时间,提出基于无线传输参数自适应的加强学习优化方案。仿真结果表明,该方法可以显著提升无线通信系统性能。展开更多
针对无线通信技术在高速列车旅客服务中的应用,对第3代通信系统、车载无线网络以及飞机舱内娱乐系统做了技术分析,提出了基于无线局域网(Wireless Local Area Network,WLAN)的高速列车旅客娱乐资讯系统(Passenger Entertainment and Inf...针对无线通信技术在高速列车旅客服务中的应用,对第3代通信系统、车载无线网络以及飞机舱内娱乐系统做了技术分析,提出了基于无线局域网(Wireless Local Area Network,WLAN)的高速列车旅客娱乐资讯系统(Passenger Entertainment and Information System,PEIS)的系统构架,描述了系统的功能特点。该系统的应用可极大提升旅客乘车体验要求。展开更多
数据存储是有效提高系统性能的方法之一.由于受带宽和无线传输速度的限制,将频繁出现的数据存储在移动数据库系统中显得尤为重要.本文实现了一个数据存储的算法(HighFrequent Data Caching),并通过模拟的方法实现了HFDC与经典的LRU(Leas...数据存储是有效提高系统性能的方法之一.由于受带宽和无线传输速度的限制,将频繁出现的数据存储在移动数据库系统中显得尤为重要.本文实现了一个数据存储的算法(HighFrequent Data Caching),并通过模拟的方法实现了HFDC与经典的LRU(Least Recently Used)两个算法在性能上的比较.展开更多
基金supported by the Major State Basic Research Development Program of China(973 Program No.2012CB316100)the National Natural Science Foundation of China(NSFC No.61032002)the Innovative Intelligence Base Project(111 Project No.111-2-14)
文摘The high-speed railway and high-way networks are now expanding at a phenomenal speed in Chinaand in many other parts of the world. The related broadband wireless communication over high-speed trains and highway vehicles is a very challenging task due to hostile transmission channel conditions. The demand for such services is growing rapidly, following the proliferation of laptop/tablet computers and smart phones. This motivates the research on wireless communications in the high mobility environments.
基金supported by the National Natural Science Foundation of China (No. 61309025)the Hunan Provincial Natural Science Foundation of China (No. 2017JJ2332)+1 种基金the National Key Technology R&D Program (No. 2015BAH05F02)the Fundamental Research Funds for the Central Universities of Central South University (No. 2017zzts146)
文摘With the increasing utilization of High-Speed Trains （HSTs）, the need for a reliable and high-bandwidth Internet access under high-speed mobility scenarios has become more demanding. In static, walking, and low mobility environments, TCP/IP （transmission control protocol/Internet protocol） can work well. However, TCP/IP cannot work well in high-speed scenarios because of reliability and handoff delay problems. This is mainly because the mobile node is required to maintain the connection to the corresponding node when it handovers to another access point node. In this paper, we propose a named data networking wireless mesh network architecture for HST wireless communication （NDN-Mesh-T）, which combines the advantages of Wireless Mesh Networks （WMNs） and NDN architectures. We attempt to solve the reliability and handoff delay problems to enable high bandwidth and low latency in Internet access in HST scenarios. To further improve reliability and bandwidth utilization, we propose a Direction-Aware Forwarding （DAF） strategy to forward Interest packet along the direction of the running train. The simulation results show that the proposed scheme can significantly reduce the packet loss rate by up to 51% compared to TCP/IP network architecture. Moreover, the proposed mechanism can reduce the network load, handoff delay, and data redundancy.
文摘目前,国内高速铁路使用基于全球铁路移动通信系统(Global System for Mobile Communications-Railway,GSM-R)的双向无线通信系统,实现列车与地面之间的安全信息传输。然而,无线通信存在传输延迟和丢包,严重时会影响运行效率,因此需要研究GSM-R系统服务质量(Quality of Service,QoS)参数,以满足实时性和可用性需求。选取传输延时作为待优化的GSM-R无线通信系统QoS参数,定量分析端到端传输延迟时间,提出基于无线传输参数自适应的加强学习优化方案。仿真结果表明,该方法可以显著提升无线通信系统性能。
文摘针对无线通信技术在高速列车旅客服务中的应用,对第3代通信系统、车载无线网络以及飞机舱内娱乐系统做了技术分析,提出了基于无线局域网(Wireless Local Area Network,WLAN)的高速列车旅客娱乐资讯系统(Passenger Entertainment and Information System,PEIS)的系统构架,描述了系统的功能特点。该系统的应用可极大提升旅客乘车体验要求。
文摘数据存储是有效提高系统性能的方法之一.由于受带宽和无线传输速度的限制,将频繁出现的数据存储在移动数据库系统中显得尤为重要.本文实现了一个数据存储的算法(HighFrequent Data Caching),并通过模拟的方法实现了HFDC与经典的LRU(Least Recently Used)两个算法在性能上的比较.
