3G无线多媒体与NGN网络互连技术研究

3G 32 4M是 3GPP和 3GPP2提出的无线多媒体通信协议 ,而H .32 3/SIP是NGN分组网络中的多媒体通信协议 ,支持两种协议族的设备存在互连互通问题 ,本文研究了支持两者互连的H .2 4 8扩展协议 ,在此基础上提出基于软交换技术实现 3G无线多媒体与NGN网络互连的分离媒体网关方案 ,并对方案的实现机制给予了深入探讨。     

3GPP网络同WLAN互连方案分析

WLAN作为一种无线接入方式,是3G接入技术的一种补充,能为3G用户提供高速稳定的数据业务,因此二者间的互连受到了世界范围内的关注.文章从互连位置的选择出发,总结了主流的紧耦合、网关和松耦合方案.简要介绍了目前3GPP的提议方案,并就各个方案的优缺点进行了比较.     

基于3G-324M和SIP的3G可视电话互通研究

可视电话业务对网络带宽、时延抖动和丢包率都有较高的要求。中国目前的第三代移动通信技术（3G）网络制式使用不同的无线技术,这使得3G网络中可视电话业务在实现的技术方式上也不同。此处主要研究3G网络中基于3G-324M和SIP协议为基础的电路域和分组域可视电话的实现技术,包括控制协议和呼叫流程。同时针对各自不同的实现方式探讨互通的具体形式,在深入分析可视电话互通理论的基础上设计了互通网关的结构,这对于实现不同制式下的可视电话业务互通具有重要的参考价值。     

从IPv4向IPv6的过渡

目前,IPv6及相关协议已经相对成熟.然而,IPv4网络向IPv6网络的过渡和互通仍然是个艰巨的任务,直接影响了IPv6的发展.本文在对现有的各种互通与过渡方案进行综合分析的基础上,针对目前转换与互通中所存在的问题,提出了一种穿透NAT实现IPv6终端互连的隧道机制.该机制可以支持所有常见的NAT类型,无需特殊的IPv6地址前缀,可以向用户提供固定的IPv6地址.另外,针对IPv6网络和IPv4网络间的信息交互的不断增加,而基于通用处理器的IPv4/IPv6转换网关很难满足性能需求的现状,基于专用网络处理器平台研发了高性能的IPv4/IPv6转换网关,在IPv4与IPv6网络间实现了高性能的地址和协议转换,为IPv4网络向IPv6网络的平滑升级提供了保证.     

帧中继与ATM——比较与互通互连

对当今飞速发展的两种重要通信新技术——帧中继与ATM进行了比较;并探讨了二者互通互连的实现方案。通过对帧中继和ATM两者在产生、发展应用诸方面的比较,从工程技术角度对二者进行了分析;从应用的角度对二者在协议互操作性及网络互连互通诸方面进行了研究,得到了一些结果,以供有关工程技术人员参考。     

基于4G的应急通信在安徽电力的应用

为提高应对突发事件的能力,安徽省电力公司建设了基于4G通信技术的应急通信系统.提出了3G 公网,微波自组网多种通信模式互补通信的方案,实现应急区域无盲区覆盖;设计开发了基于 IP软交换技术及 DSP 信号处理技术的多种语音网络互连模块,可以将不同类型的语音通信终端融合起来,实现互连互通,在视频传输方面,利用微波通信技术,解决了公网中断的应急情况下语音视频的实时传输.为应急救援人员提供了新的通信手段.     

野战网与本地网互通信令变换的实现

通过对野战网中继群信令标准和公用网中国1号信令标准的研究,提出了两种网络互连时,两种不同体制信令间的互通方案,编制了相应的协议转换软件,并在设备上进行了实现。     

3GPP网络NWLAN互连方案分析

WLAN作为一种无线接入方式，是3G接入技术的一种补充，能为3G用户提供高速稳定的数据业务，因此二者间的互连受到了世界范围内的关注。文章从互连位置的选择出发，总结了主流的紧耦合、网关和松耦合方案。简要介绍了目前3GPP的提议方案，并就各个方案的优缺点进行了比较。     

固网与移动视频互通方案研究

随着3G网络大规模的部署,3G可视终端用户快速增长,如何促进3G和固网两网的共同快速发展、解决固网和移动用户多媒体可视业务互通是本文研究的主要内容。本文首先介绍了固网与移动视频互通的基本原理,然后从视频互通的关键技术入手,提出3种可行的解决方案并进行了分析和比较,最后以实际案例对固移用户视频互通的组网方案及路由组织进行说明。     

基于IP的核心网侧Iu接口分析与实现

Iu接口是第三代移动通信系统中无线接入网与核心网之间的接口,用于完成控制面和用户面的数据传输,实现无线接入网与核心网的互连互通。介绍了基于IP的Iu接口定位和协议结构,提出了一种核心网侧Iu接口的实现方案,该方案具有配置灵活和可移植性强的特点,并给出了方案的业务处理流程、系统结构和实现流程。     

未来移动通信系统中的无线资源管理

文章结合当前正在研究的后3代(B3G)、第4代(4G)移动通信系统的发展和处于运营及推广阶段的第3代移动通信系统,分析了未来移动通信系统中无线资源管理系统的关键技术,探讨了多体制标准下的无线通信网络和多种业务情况下的无线资源管理的研究方向。     

Radio resource allocation in third generation mobile communicationsystems

Code-division multiple access has been widely accepted as the major multiple access scheme in third-generation mobile communication systems. Wide-band CDMA and its hybrid associate time-division CDMA are key elements of the IMT2000 framework of standards. Since the beginning of the 1990s there has been enormous research activity in analysis of the soft (i.e., interference limited) capacity of these CDMA-based systems. Optimal usage of the soft capacity to provide, maintain, and guarantee QoS for different service classes is now becoming a very important issue. Therefore, interest in radio resource allocation has recently. This article presents an overview of RRA schemes (primarily for CDMA-based systems) that are flexible, support traffic services with various QoS requirements, minimize call/session blocking and dropping probabilities, and have acceptable radio resource utilization     

未来移动通信的展望

第三代移动通信系统虽然仍处于预商用阶段,但许多公司和组织早已对三代以后的移动通信系统及其关键技术开始前瞻性的预研工作了。本文首先分析了未来移动通信系统的发展趋势,认为未来的移动通信系统将具有更高的传输速率、更高的频谱利用率,同时支持与基于IP的其它数据网络的互联互通;最后,分别描述了在未来系统中可能采用的网络结构和多种无线传输技术。     

Applying IP over wmATM technology to third generation wirelesscommunications

With the rapid development of third-generation wireless mobile communication systems worldwide, the wireless mobile ATM enhanced software radio platform has taken the lead in the implementation process, which helps construct a broadband wireless pipe and “IP over wmATM” open signaling suite to support various common air interfaces for the wireless industry. This article presents the implementational issues using the IP over wmATM solution for 3G broadband wireless mobile communication systems. It includes the design of the wmATM medium access controller, protocol stack, wmATM module definition, and software radio platform, as well as IP unified 3G wireless networks     

Direct conversion radio for digital mobile phones-design issues, status, and trends

Applications of direct frequency-conversion techniques have been rapidly getting attention of radio designers worldwide. This paper focuses on bringing out key implementation challenges of direct conversion receivers and transmitters targeted for different second- and third-generation mobile phone standards like global system for mobile communication, code division multiple access (cdmaOne and CDMA 2000), and wide-band code division multiple access. Techniques and tradeoffs to arrive at optimal implementation are highlighted. Some of the commercially available application-specific integrated circuits that are based on direct conversion architecture and their salient features are summarized.     

Heterogeneous Networks to Support User Needs with Major Challenges for New Wideband Access Systems

Third generation mobile radio systems are currently being deployed in different regions of the world. Future systems beyond the third generation are already under discussion in international bodies and forums such as ITU, WWRF and R&D programs of the European Union and in other regions. These systems will determine the research and standardization activities in mobile and wireless communication in the next years. Based on the experience from the third generation future systems will be developed mainly from the user perspective with respect to potential services and applications including traffic demands. This is directly related to the paradigm shifts from the first generation to systems beyond third generation. International bodies are already discussing basic system requirements. The basic system architecture of heterogeneous networks with different complementing access systems is from the today's perspective the most economic approach for systems beyond 3G to satisfy user and operator needs for reasonable cost. Such system architectures enable the deployment of system capacity according to the traffic requirements with the user experience ``Optimally Connected, Anywhere and Anytime' with seamless service provision between different access systems. New radio interface components with high data rate as additional components of systems beyond 3G are being proposed in international bodies. Key issues of such systems are coverage due to reduced range and the huge spectrum demand. In this paper the international context, the user perspective, revenue and traffic expectations are presented. This results in the basic system requirements and the potential system architecture of heterogeneous networks. Major challenges for the new wideband radio interfaces are the impact on range and spectrum demand. Basic investigations are presented on these issues to critically review requirements on future systems.     

Radio Access in a System Beyond 3G

This paper gives an overview of the envisaged requirements and building blocks for mobile communication systems beyond 3G (B3G). It analyzes the drivers for such a system taking into consideration the key areas “services”, “network” and “radio” and presents possible corner stones for an appropriate radio interface. Hence it gives an overview how a future system B3G may look like.     

Relay Technologies for WiMAX and LTE-Advanced Mobile Systems

Relay technologies have been actively studied and considered in the standardization process of next-generation mobile broadband communication systems such as 3GPP LTE-Advanced, IEEE 802.16j, and IEEE 802.16m. This article first introduces and compares different relay types in LTE-Advanced and WiMAX standards. Simulation results show that relay technologies can effectively improve service coverage and system throughput. Three relay transmission schemes are then summarized and evaluated in terms of transmission efficiency under different radio channel conditions. Finally, a centralized pairing scheme and a distributed pairing scheme are developed for effective relay selection. Simulation results show that the proposed schemes can maximize the number of served UE units and the overall throughput of a cell in a realistic multiple-RS-multiple-UE scenario.     

5G技术浅析

随着中国广电网络顺利拿到5G牌照以及顺利上市,未来广电在5G领域的应用将会越来越多,5G在移动领域的应用最为普及,而移动通信系统发展的最重要原因是不断变化的需求。这些需求使得移动通信所期望的需求逐步增加。最初只有语音传输的系统,随后出现了提供高质量多媒体传输和Internet连接的新系统。5G则是目前的热门话题与未来的发展趋势。在移动通信中,从1G到5G的技术发生变化所不断涌现出的新技术推动了整个社会的变革。当前的移动通信标准向其用户提供服务较为有限,还有极大的提升空间。     

软件无线电基站接收单元的实现

由于软件无线电使得通信系统具有很好的通用性、灵活性,并使系统互联和升级变得方便,它已成为个人移动通信发展的关键技术之一.文中基于软件无线电的思想,讨论了个人移动通信系统基站接收单元的实现方案.