无线承载测试

无线承载测试的应用取决于UE上行、下行无线接入能力以及UE支持的电信业务和承载业务。不同的电信业务和承载业务需要不同无线承载。对无线承载配置统一规定，确保了UE和不同网络之间的互操作性，解决了UE和不同网络之间的网络兼容性问题。无线接入承载测试就是来验证UE在建立业务时是否对应规定的无线承载。     

移动无线接入IP承载演进策略探讨

通信业务迅猛发展促进了移动网络IP化进程。针对移动运营商现网架构和业务环境,文章分析了无线接入网的IP化需求,并阐述了无线接入全IP承载的演进方向及过渡解决方案。     

LTE中的RRC协议研究

LTE无线接口协议的作用是建立、重新配置和释放无线承载,它能够为传输EPS承载提供各种方法.描述了UE的状态与状态转换,包括E-UTRAN状态与RAT状态间的移动与信令无线承载(SRB),同时介绍了系统信息广播、寻呼、RRC连接、无线承载的建立、切换、CS语音回落、UE能力转移,以及处理一般错误的工作流程.     

接入网市场简析

接入网作为各种电信业务接入公众网的必经之路,其承载业务的能力和质量直接关系到业务的开展和网络的运营.随着运营商之间的竞争日趋激烈,接入网的建设已成为各运营商近期关注的重点之一.接入网的形态很多,本文仅就目前讨论较多的无线接入、无源光纤网、Cable modem、金属用户线上的XDSL(主要是ADSL)几个方面的市场情况做些简单分析.     

IP城域网业务接入控制层业务备份技术探讨

越来越多的电信业务通过IP网络承载,对IP城域网的可靠性提出了极高的要求.业务接入控制层在IP城域网中是多业务融合承载的关键设备,在网络中承担着承上启下的功能.根据运营实践和业务测试,分析了业务接入控制层设备业务备份目前的技术现状,提出了在新型承载网络架构中构建高可靠性业务接入控制层的方法和建议.     

无线数字家庭网络的发展

家庭网络的无线化是未来家庭网络的发展趋势.根据在不同无线接入承载环境,本文将无线家庭网络分成了四类,并从其应用场合、网络技术和标准上对它们进行了分析.最后,总结出未来无线家庭网络是一个全IP的异构网络,多媒体流传输是它的主要业务之一.网络融合、提高传输速率以及无线资源管理将会成为未来的研究重点.     

SCDMA无线市话系统的短信容量

文章首先分析了SCDMA无线市话系统的短信传输机制和影响短信传输的因素;接着从无线传输承载能力入手,分析了SCDMA系统承载短信群发业务时的短信容量;然后通过在SCDMA无线接入网络的测试,验证了SCDMA无线接入系统的短信容量。     

宽带无线技术—LMDS

随着电信和因特网业务的不断增长,中小型用户接入骨干网络成了棘手的瓶颈问题,而且这种矛盾随着业务量的增加愈来愈突出。这就是人们常说的接入网络中的“最后一公里”问题,它成了制约电信业快速发展的重要因素。以Internet为代表的网络应用正向语音、数据、图像的大信息量快速发展的同时,作为承载电信业务的用户接入技术也必然按照高速宽带接入、承载综合业务     

5G业务无线承载方案探讨

由于5G业务的多样性和网络的复杂性,传统的单独基于信道质量或基于负荷的无线承载策略并不能满足用户差异化的网络需求.因此5G网络需要智能无线承载策略,即以感知提升为目标,综合考虑业务需求、网络负荷、信道质量、终端能力等各种因素,将用户引导到最优目标频点,以实现网络资源与业务需求精确匹配,实现业务体验最优.     

几种WAP承载方式的比较

无线应用协议（WAP）作为无线Internet的解决方案,目前受到了广泛的关注。移动网络的数据承载业务作为实现WAP应用的必由之路起着关键的作用。分析研究了GSM网络中的几种数据承载业务,给出了各种数据承载业务分别作为WAP的承载时的实现方式,并对其优劣之处进行了分析和比较。     

TD-LTE系统ESM层默认承载建立过程的研究与实现

3GPP组织启动了长期演进(LTE)与系统框架演进(SAE)项目。针对未来数据业务高速、突发性的特征,LTE会话管理子层引入了新的QoS机制,即默认承载,当UE附着到网络的同时为该UE建立一条固定速率的承载,提升用户的业务特性。在设计开发上,引入了SDL与TTCN协仿真对ESM代码进行仿真测试,通过默认承载建立过程的协议流程与MSC做对比,实现了预期的目标。     

Performance analysis for UMTS networks with queued radio access bearers

The Universal Mobile Telecommunications System (UMTS) network consists of a core network (CN) and a UMTS terrestrial radio access network (UTRAN). The UTRAN offers radio access bearer (RAB) services between the user equipment (UE) and the CN to support mobile multimedia applications with different quality of service (QoS) requirements. Depending on the requested QoS, different types of RABs can be established at the request of the CN. The UTRAN then has to establish and maintain the RAB with the requested QoS. We study the queueing of RABs as a means for improving the bandwidth utilization while minimizing the RAB blocking probability. We develop an analytical model to study the performance for UTRAN with queued RABs in terms of RAB blocking probability and average queueing time of queued RABs. From an analytic point of view, the main contribution of this paper is the introduction of a novel recursion for the computation of the performance measures.     

Module count-based overflow-control scheme for UMTS high-speed downlink packet access

In the universal mobile telecommunication system, the user equipment (UE) communicates with all cells in the active set through the air interface. Multiple radio links between the UE and the cells may reduce the transmission speed due to interference. In high-speed downlink packet access (HSDPA), only one serving cell is selected in the active set for high-speed downlink transmission. When the radio link quality between the serving cell and the UE degrades below some threshold, the best cell (in terms of the radio characteristics) in the active set is selected as the new serving cell and the UE switches from the old serving cell to the new serving cell. This action is referred to as frame synchronization. The frame-synchronization information may be delivered through more than one wireless transmission, which introduces long delay for the frame-synchronization process. In this paper, we propose an overflow-control scheme with module count for HSDPA, which guarantees that the frame-synchronization information is delivered through one wireless transmission and that when the UE switches wireless link to the new serving cell, no packet frames are lost.     

TD-SCDMA/GSM双模系统两模式间小区选择的研究

TD-SCDMA技术是中国具有自主知识产权的第三代移动通信技术.从中国移动通信的发展现状看,在中国,未来TD-SCDMA网络将和GSM网络长期并存,而小区选择是移动终端能够成功驻留在合适的小区并保证呼叫成功率的重要功能,同样也是不同无线通信系统间的主要互操作行为之一.文中根据协议给出TD-SCDMA/GSM双模终端软件结构图,对TD-SCDMA/GSM双模系统两模式间小区选择问题进行了深入的探讨,并对两模式间小区选择建立过程模型.     

Overflow control for UMTS high-speed downlink packet access

This paper proposes overflow control schemes to support high-speed downlink packet access (HSDPA) mechanism in the universal mobile telecommunication system (UMTS). To access the UMTS services, a user equipment (UE) communicates with all cells (base stations) in an active set. However, multiple links between the UE and the cells in the active set may reduce the transmission speed due to interference. Third-Generation Partnership Project specification TR 25.950 proposes HSDPA. In this mechanism, the UE only selects one cell (referred to as the serving cell) in the active set for high-speed downlink transmission. In HSDPA, the radio network controller sends the packet frames to the cells in the active set. For the serving cell, the packet frames are forwarded to the UE. On the other hand, every nonserving cell in the active set queues the packet frames in a buffer. If the link quality between the serving cell and the UE degrades below some threshold, the UE selects the best cell in the active set as the new serving cell. Since the nonserving cells do not send packet frames to the UE, their buffers may overflow. In this paper, we propose schemes to address the buffer overflow issue. Our schemes guarantee that when the buffer of a nonserving cell is full, the previously received packet frames in the buffer can be safely dropped, and after the UE has switched wireless link to the new serving cell, no packet frames are lost.     

A-GPS终端一致性测试

A-GPS(Assisted Global Positioning System)是一种通过移动通信网络辅助的全球定位技术,此技术结合了两类位置信息,一类是移动台通过自身GPS接收机获得的,而另一类则是移动台通过移动通信网络获取的。A-GPS技术可以在2G,3G以及未来4G的通信网络中部署应用,移动终端应用A-GPS定位业务,需要增加A-GPS接收机及相应信号处理模块。A-GPS的终端一致性认证,即对于移动终端的A-GPS功能部分进行一致性验证,目前国际上采用的包含A-GPS一致性测试规范有3GPP51.010,3GPP34.171,3GPP34.123,3GPP2C.S0036,3GPP2C.S0059,OMA-ETS-SUPL等,本文对上述规范做了详细介绍。     

IPTV业务保障及其关键技术研究

IPTV是当前最热门技术领域之一,主要的电信服务提供商都在努力推出自己的IPTV业务。研究了IPTV业务保障问题及其重要意义,提出了从承载网络、内容传送及业务体验三个方面实现IPTV业务保障并分析了其中的关键技术。     

LTE终端类型分析及其测试

LTE终端存在多种类型以满足运营商的业务差异化需求。本文对标准化组织定义的4种LTE终端类型进行了分析,比较了不同类型终端与网络协商业务承载域的过程,介绍了不同类型之间的转换条件和过程,并对不同LTE终端类型的测试策略进行了比较说明。     

Telephones take flight

That icon of technology, the passenger jet, was one of the last places in the developed world in which it was impossible to make a telephone call. Now this bastion of isolation is succumbing to digital technology. In-flight passenger telephone services, known generically as airborne public correspondence (APC), have now become an established fact of air travel. Here, the author describes how there are two quite different approaches to providing these services for the passenger: some systems use satellites to provide the radio bearer between the aircraft and the ground, while the so-called `terrestrial' systems use direct air-to-ground radio links     

第三代移动通信WCDMA无线接入网

WCDMA（UTRA FDD）是第三代移动通信的主流标准,预计会在全球大多数地区得到广泛的应用。WCDMA的标准化进程会影响到其无线接徼网络（RAN（的研发,生产和运营,从当前标准化进程和技术趋势看,Release 99是必经的阶段,对于无线接入网络设备和相应的网络规划和优化软件,需要按照高的频谱利用率,灵活的多业务承载能力,多样化组网方式等要求来完成,以满足移动难环境和电信运营的需要。