LTE（Long Term Evolution，长期演进）是由3GPP（第三代合作伙伴计划组织）制定的移动通信体系最新标准。LTE是3G与4G之间的一个过渡，俗称3．9G或者超3G。它以OFDM（正交频分复用）、MIMO（多进多出）等先进的物理层技术为核心，改进...LTE（Long Term Evolution，长期演进）是由3GPP（第三代合作伙伴计划组织）制定的移动通信体系最新标准。LTE是3G与4G之间的一个过渡，俗称3．9G或者超3G。它以OFDM（正交频分复用）、MIMO（多进多出）等先进的物理层技术为核心，改进并增强了3G空中接口技术，展开更多
研究了LTE(Long Term Evolution)系统下行链路的信道估计算法。基于LTE通信协议中参考信号的设计,提出了一种新的信道估计算法。该算法引入ACM(Adaptive Channel Manager,自适应控制器)和噪声抑制滤波器,将ACM的输出与预先设定的门限比...研究了LTE(Long Term Evolution)系统下行链路的信道估计算法。基于LTE通信协议中参考信号的设计,提出了一种新的信道估计算法。该算法引入ACM(Adaptive Channel Manager,自适应控制器)和噪声抑制滤波器,将ACM的输出与预先设定的门限比较,若输出高于此门限则使用噪声抑制滤波器进行滤波。仿真结果表明,此算法相对于LTE信道估计算法在增加很少计算复杂度的情况下,获得了性能改善。展开更多
At present, the major drawback for mobile phones is the issue of power consumption. As one of the alternatives to decrease the power consumption of standard, power-hungry location-based services usually require the kn...At present, the major drawback for mobile phones is the issue of power consumption. As one of the alternatives to decrease the power consumption of standard, power-hungry location-based services usually require the knowledge of how individual phone features consume power. A typical phone feature is that the applications related to multimedia streaming utilize more power while receiving, processing, and displaying the multimedia contents, thus contributing to the increased power consumption. There is a growing concern that current battery modules have limited capability in fulfilling the long-term energy need for the progress on the mobile phone because of increasing power consumption during multimedia streaming processes. Considering this, in this paper, we provide an offline meaning sleep-mode method to compute the minimum power consumption comparing with the power-on solution to save power by implementing energy rate adaptation(RA) mechanism based on mobile excess energy level purpose to save battery power use. Our simulation results show that our RA method preserves efficient power while achieving better throughput compared with the mechanism without rate adaptation(WRA).展开更多
The challenges brought by broadband wireless access technologies to cellular mobile communication technologies speed up the study and standardization of 3G evolution technologies that support higher data rates. Both t...The challenges brought by broadband wireless access technologies to cellular mobile communication technologies speed up the study and standardization of 3G evolution technologies that support higher data rates. Both the 3GPP and the 3GPP2 have launched research programs on the study and standardization of the emerging 3G evolution technologies. The Long Term Evolution (LTE) program of 3GPP has made progress in key technical indexes of air interface, wireless network architecture and high-level protocols. At the same time, the Air Interface Evolution (AIE) program of 3GPP2 has made study achievements in the formulation of air interface standards for Layer 2 and upper layers, as well as for the physical layer.展开更多
长期演进(Long Term Evolution,LTE)作为当前主流的无线通信技术之一,其性能优化是当前研究的热点。文章针对LTE网络中的资源分配问题展开研究,通过分析正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术的基本原理,...长期演进(Long Term Evolution,LTE)作为当前主流的无线通信技术之一,其性能优化是当前研究的热点。文章针对LTE网络中的资源分配问题展开研究,通过分析正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术的基本原理,深入探讨其资源分配问题。针对传统粒子群优化(Particle Swarm Optimization,PSO)算法在资源分配过程中存在的局限性,文章研究一种基于混沌优化的PSO算法,以提高算法的全局搜索能力和收敛速度。通过在NS-3仿真平台上进行实验验证,结果表明混沌优化的PSO算法在不同网络负载情况下均能有效增加系统吞吐量,相比传统PSO算法具有更好的性能表现。展开更多
文章探讨长期演进(Long Term Evolution,LTE)无线通信技术与物联网技术的融合在物联网网关设计中的应用。LTE技术具有网络容量大、吞吐量高和并行传输能力强的优势,结合物联网技术的智能交互和信息化网络环境,共同提升物联网的连接效率...文章探讨长期演进(Long Term Evolution,LTE)无线通信技术与物联网技术的融合在物联网网关设计中的应用。LTE技术具有网络容量大、吞吐量高和并行传输能力强的优势,结合物联网技术的智能交互和信息化网络环境,共同提升物联网的连接效率和数据传输稳定性。基于对LTE无线通信和物联网技术的简要分析,探索基于LTE无线通信的物联网网关设计。使用CMW500无线设备空口综合性测试仪与SecureCRT终端仿真程序测试网关联网功能。测试结果显示,该网关设计能够搜网成功并连接网络,具备一定普适性。展开更多
随着科技的不断发展,人们对信息服务的需求越来越高。在无线通信技术方面,长期演进(Long Term Evolution,LTE)被广泛应用于移动通信领域,因其高速、高质量的数据传输能力而备受青睐。物联网技术的出现和发展为各行各业带来了巨大的机遇...随着科技的不断发展,人们对信息服务的需求越来越高。在无线通信技术方面,长期演进(Long Term Evolution,LTE)被广泛应用于移动通信领域,因其高速、高质量的数据传输能力而备受青睐。物联网技术的出现和发展为各行各业带来了巨大的机遇和挑战。将LTE无线通信技术与物联网技术相结合,可以进一步提高用户的信息服务体验,为后续发展提供坚实的基础。展开更多
LTE(Long Term Evolution,长期演进)是3GPP近两年来启动的最大的新技术研发项目,这种以OFDMFDMA为核心的技术,可以被看作"准4G"技术。它改进并增强了3G的空中接入技术,采用OFDM和MIMO作为其无线网络演进的唯一标准。当前,全...LTE(Long Term Evolution,长期演进)是3GPP近两年来启动的最大的新技术研发项目,这种以OFDMFDMA为核心的技术,可以被看作"准4G"技术。它改进并增强了3G的空中接入技术,采用OFDM和MIMO作为其无线网络演进的唯一标准。当前,全球的移动通信产业对LTE都寄予了厚望,引起普遍关注,期望这一技术能够增强移动通信产业持续发展的能力。在2008全球移动大会上,主流设备厂商不约而同地发布了LTE的研究成果和后续演进策略,LTE被进一步确立了向3G后续演进或者说向4G发展的核心地位。据专家预计,到2014年全球LTE用户数将达3900万,设备收入将达90亿美元。展开更多
Vehicular ad hoc networks （VANETs） that use the IEEE 802.11p communication standard face a number of challenges, not least when it comes to safety messages on the VANET control channel （CCH） where short delay time...Vehicular ad hoc networks （VANETs） that use the IEEE 802.11p communication standard face a number of challenges, not least when it comes to safety messages on the VANET control channel （CCH） where short delay times and reliable delivery are of pri- mary importance. In this paper we propose a vehicular machine-to-machine （VM2M） overlay network that uses Long Term Evolu- tion （LTE） physical random access channel （PRACH） to emulate VANET CCH. The overlay network uses dedicated preambles to separate vehicular traffic from regular LTE traffic and a cartier sense multiple access with collision avoidance （CSMA-CA） layer similar to the one used in IEEE 802.15.4 to avoid the four step handshake and the overhead it incurs. The performance of the pro- posed overlay is evaluated under a wide range of PRACH parameters which conform to the scenarios with high vehicle velocities and large distances between roadside units （RSUs） that may be encountered in rural areas and on highways.展开更多
相对于传统的基于通信的列车运行控制系统(communication based train control,CBTC),下一代列控系统将具有架构可靠、速率快、成本低以及服务质量高等优点,且数据通信系统的可用性能够保障列车的安全和高效运行。面向下一代列控系统,...相对于传统的基于通信的列车运行控制系统(communication based train control,CBTC),下一代列控系统将具有架构可靠、速率快、成本低以及服务质量高等优点,且数据通信系统的可用性能够保障列车的安全和高效运行。面向下一代列控系统,首先设计基于LTE-M(long term evolution-metro,LTE-M)的通信系统结构;然后针对下一代列控系统典型场景,利用确定与随机Petri网(deterministic and stochastic petri nets,DSPN)进行可用性建模,最后进行模型求解和可用性评估。仿真结果显示,基于LTE-M的下一代列控数据通信系统能够满足实际通信需求,其可用性分析方法可以完成数据通信系统的可用性建模与评估。展开更多
文摘研究了LTE(Long Term Evolution)系统下行链路的信道估计算法。基于LTE通信协议中参考信号的设计,提出了一种新的信道估计算法。该算法引入ACM(Adaptive Channel Manager,自适应控制器)和噪声抑制滤波器,将ACM的输出与预先设定的门限比较,若输出高于此门限则使用噪声抑制滤波器进行滤波。仿真结果表明,此算法相对于LTE信道估计算法在增加很少计算复杂度的情况下,获得了性能改善。
基金supported by X-Project funded by the Ministry of Science,ICT&Future Planning under Grant No.NRF-2015R1A2A1A16074929
文摘At present, the major drawback for mobile phones is the issue of power consumption. As one of the alternatives to decrease the power consumption of standard, power-hungry location-based services usually require the knowledge of how individual phone features consume power. A typical phone feature is that the applications related to multimedia streaming utilize more power while receiving, processing, and displaying the multimedia contents, thus contributing to the increased power consumption. There is a growing concern that current battery modules have limited capability in fulfilling the long-term energy need for the progress on the mobile phone because of increasing power consumption during multimedia streaming processes. Considering this, in this paper, we provide an offline meaning sleep-mode method to compute the minimum power consumption comparing with the power-on solution to save power by implementing energy rate adaptation(RA) mechanism based on mobile excess energy level purpose to save battery power use. Our simulation results show that our RA method preserves efficient power while achieving better throughput compared with the mechanism without rate adaptation(WRA).
基金National "863"Program of China (No. 2005AA123410)
文摘The challenges brought by broadband wireless access technologies to cellular mobile communication technologies speed up the study and standardization of 3G evolution technologies that support higher data rates. Both the 3GPP and the 3GPP2 have launched research programs on the study and standardization of the emerging 3G evolution technologies. The Long Term Evolution (LTE) program of 3GPP has made progress in key technical indexes of air interface, wireless network architecture and high-level protocols. At the same time, the Air Interface Evolution (AIE) program of 3GPP2 has made study achievements in the formulation of air interface standards for Layer 2 and upper layers, as well as for the physical layer.
文摘长期演进(Long Term Evolution,LTE)作为当前主流的无线通信技术之一,其性能优化是当前研究的热点。文章针对LTE网络中的资源分配问题展开研究,通过分析正交频分复用(Orthogonal Frequency Division Multiplexing,OFDM)技术的基本原理,深入探讨其资源分配问题。针对传统粒子群优化(Particle Swarm Optimization,PSO)算法在资源分配过程中存在的局限性,文章研究一种基于混沌优化的PSO算法,以提高算法的全局搜索能力和收敛速度。通过在NS-3仿真平台上进行实验验证,结果表明混沌优化的PSO算法在不同网络负载情况下均能有效增加系统吞吐量,相比传统PSO算法具有更好的性能表现。
文摘文章探讨长期演进(Long Term Evolution,LTE)无线通信技术与物联网技术的融合在物联网网关设计中的应用。LTE技术具有网络容量大、吞吐量高和并行传输能力强的优势,结合物联网技术的智能交互和信息化网络环境,共同提升物联网的连接效率和数据传输稳定性。基于对LTE无线通信和物联网技术的简要分析,探索基于LTE无线通信的物联网网关设计。使用CMW500无线设备空口综合性测试仪与SecureCRT终端仿真程序测试网关联网功能。测试结果显示,该网关设计能够搜网成功并连接网络,具备一定普适性。
文摘随着科技的不断发展,人们对信息服务的需求越来越高。在无线通信技术方面,长期演进(Long Term Evolution,LTE)被广泛应用于移动通信领域,因其高速、高质量的数据传输能力而备受青睐。物联网技术的出现和发展为各行各业带来了巨大的机遇和挑战。将LTE无线通信技术与物联网技术相结合,可以进一步提高用户的信息服务体验,为后续发展提供坚实的基础。
文摘LTE(Long Term Evolution,长期演进)是3GPP近两年来启动的最大的新技术研发项目,这种以OFDMFDMA为核心的技术,可以被看作"准4G"技术。它改进并增强了3G的空中接入技术,采用OFDM和MIMO作为其无线网络演进的唯一标准。当前,全球的移动通信产业对LTE都寄予了厚望,引起普遍关注,期望这一技术能够增强移动通信产业持续发展的能力。在2008全球移动大会上,主流设备厂商不约而同地发布了LTE的研究成果和后续演进策略,LTE被进一步确立了向3G后续演进或者说向4G发展的核心地位。据专家预计,到2014年全球LTE用户数将达3900万,设备收入将达90亿美元。
文摘Vehicular ad hoc networks （VANETs） that use the IEEE 802.11p communication standard face a number of challenges, not least when it comes to safety messages on the VANET control channel （CCH） where short delay times and reliable delivery are of pri- mary importance. In this paper we propose a vehicular machine-to-machine （VM2M） overlay network that uses Long Term Evolu- tion （LTE） physical random access channel （PRACH） to emulate VANET CCH. The overlay network uses dedicated preambles to separate vehicular traffic from regular LTE traffic and a cartier sense multiple access with collision avoidance （CSMA-CA） layer similar to the one used in IEEE 802.15.4 to avoid the four step handshake and the overhead it incurs. The performance of the pro- posed overlay is evaluated under a wide range of PRACH parameters which conform to the scenarios with high vehicle velocities and large distances between roadside units （RSUs） that may be encountered in rural areas and on highways.
文摘相对于传统的基于通信的列车运行控制系统(communication based train control,CBTC),下一代列控系统将具有架构可靠、速率快、成本低以及服务质量高等优点,且数据通信系统的可用性能够保障列车的安全和高效运行。面向下一代列控系统,首先设计基于LTE-M(long term evolution-metro,LTE-M)的通信系统结构;然后针对下一代列控系统典型场景,利用确定与随机Petri网(deterministic and stochastic petri nets,DSPN)进行可用性建模,最后进行模型求解和可用性评估。仿真结果显示,基于LTE-M的下一代列控数据通信系统能够满足实际通信需求,其可用性分析方法可以完成数据通信系统的可用性建模与评估。
