The Future of Radio Access in 3G

In the last two years, UMTS has progressed from the drawing board to prototypes and pre-release trials. Through the concentrated efforts of manufacturers and operators in the standards bodies, the 3GPP specifications for UMTS, including W-CDMA, TD/CDMA and TD/SCDMA, are currently being developed into deployable equipment for the first UMTS networks. However, human nature dictates that there is always room for improvement, with a constant drive for better performance and higher efficiency. UMTS is by no means the ultimate mobile radio access network, and, even before the first equipment rolls off the production lines, the work of the standards bodies is already looking at enhancements to the system. This paper considers some of these improvements, the evolution of W-CDMA, and the role of TDD in the ongoing developments of third generation mobile radio access.     

Mobility management: from GPRS to UMTS

This paper describes mobility management for the third‐generation mobile networks. We focus on the evolution from General Packet Radio Service (GPRS) to Universal Mobile Telecommunication System (UMTS). In this evolution, the radio access network UTRAN has been introduced, and radio‐related management is moved from the core network to UTRAN. We elaborate on how this architecture change affects the mobility management functionality, including the attach and detach procedures, location update, serving radio network controller relocation and intersystem change between GPRS and UMTS. Copyright © 2001 John Wiley & Sons, Ltd.     

UMTS — the mobile part of broadband communications for the next century

This paper outlines the path from developing broadband ISDN/ATM systems towards the European vision of the next generation mobile system — Universal Mobile Telecommunications System (UMTS).The capabilities of UMTS in terms of services and features compared to the second generation mobile system GSM, and the network technologies behind N-ISDN and B-ISDN, are discussed with proposals for technical developments to satisfy the UMTS requirements. The UMTS radio interface aspects are described and considerations on the network requirements to support these radio aspects are discussed.The requirements within the network for control, switching and transport to support the mobility, service and interconnecting network aspects of UMTS are outlined in conjunction with the technical solutions currently under discussion and some latest thoughts on a potential high-level architecture     

UMTS mobility management

The characteristics of first, second and third generation mobile communication systems are first described. The state of standardisation of the universal mobile telecommunication system (UMTS) is then outlined and the system concept is introduced. A mobility management platform which will provide uniform access to mobility functions for every user or network entity independent of the actual location of the requested function in the network is described. The mobility management platform is based on the intelligent network concept. Mobility management aims to share the processing load in the distributed UMTS environment     

Third generation PCN and the intelligent multimode mobile portable

The radio interfaces required for a third generation personal communications network (PCN), and the attributes of an intelligent multimode portable to operate within the PCN are speculated upon. After discussing key factors in determining spectral efficiency in PCNs, multiple access methods are considered for radio interfaces associated with high-capacity network nodes, microcellular networks, macrocellular networks, megacells, satellite mobile and private mobile radio. Modulation issues are then addressed, followed by source and channel coding. Some elements of a third generation PCN are considered next. Finally the authors present their views on an intelligent multimode mobile portable that will function in many different geographical environments and, in any one, be adaptive in changing its subsystems to variations in the channel conditions and local teletraffic loading     

Indoor Planning for High Speed Downlink Packet Access in WCDMA Cellular Network

The aim of this paper is to show the special characteristics of the indoor environment related to radio propagation and furthermore to radio network planning. The aspects of the radio network planning are highlighted especially for Wideband Code Division Multiple Access (WCDMA) radio access technology that is used widely in the third generation mobile networks. Moreover, the detailed planning parameters in indoor environment are studied for High Speed Downlink Packet Access (HSDPA) in order to support high throughput data applications in Universal Mobile Telecommunications System (UMTS). The final target of the paper is to compare pico cell, distributed antenna system (DAS), and radiating cable network configurations in indoor environment to provide the optimal radio conditions for the data applications, and thus to serve highest number of mobile users. Several measurement campaigns with different antenna configurations have been conducted in order to study the effect of multi path related parameters, as delay spread of the signal. Also other capacity related parameters as received signal levels, interference, throughput, and transmit power levels have been studied in order to find out the optimal solution for HSDPA in UMTS. The results clearly show that pico cells and distributed antenna system have outstanding performance in indoor propagation channel compared to radiating cable. In sense of signal quality, pico cell performance is slightly better compared to distributed antenna system. However, measurements with HSDPA indicate that practical capacity of DAS outperforms pico cells. The measurements also show that separation of the antennas is a key capacity related parameter when planning WCDMA based indoor systems.     

Lightweight Secure Roaming Mechanism Between GPRS/UMTS and Wireless LANs

The third generation partner project (3GPP) has standardized general packet radio service (GPRS) and the universal mobile telecommunications system (UMTS) to provide cell phone communications and wireless Internet services. Although the data transmission rate is lower than that of wireless local area networks (WLANs), GPRS/UMTS covers larger areas. Hence, to achieve higher speed ubiquitous access, we propose a lightweight secure roaming mechanism (LSRM) that integrates GPRS/UMTS and WLAN. Taking advantage of these two technologies, LSRM offers anonymous roaming and friendly subscriber management. Besides, we give a formal security analysis to LSRM based on BAN authentication logic.     

Planning tools for mobile networks

The RACE II project PLATON (Planning Tools for third generation mobile Networks) aims at defining a set of tools to be used for radio planning of the Universal Mobile Telecommunication Systems (UMTS) network. The paper presents studies on cell structures, propagation models, the different services and the corresponding quality-of-service and shows how these are used in the planning tools, the modular structure and the evolution of the software     

A CDMA‐based radio interface for third generation mobile systems

This paper deals with the use of a CDMA-based radio interface in third generation mobile systems (Universal Mobile Telecommunications System – UMTS, and Future Public Land Mobile Telecommunications System – FPLMTS). The paper is not intended as a detailed analysis of the radio interface performance, but as an overview of the main issues arising in a typical CDMA-based mobile system, discussing the different available technical solutions. First of all, the basic requirements of the radio interface in a third generation mobile system are outlined. In particular, the support of variable bit rate transmission, the adaptability to the different propagation and service environments and the flexibility are felt to be important topics to be discussed. Then, the main characteristics of the CDMA access technique are depicted, in relation with the above mentioned requirements, focusing in particular on the DS-CDMA radio interface designed within the RACE II – CODIT Project. In that context the paper describes some of the technical solutions proposed for the provision of advanced features such as macrodiversity, multibearer transmission and variable bit rate services. This revised version was published online in June 2006 with corrections to the Cover Date.     

Management of networks and services in a composite radio context

This article adopts the assumption that different wireless access technologies (e.g., UMTS, HIPERLAN2, and DVB-T) can be cooperating components of a composite radio infrastructure. The coordinated management of services and network in this heterogeneous context is a complex task. This article presents a service and network resource management platform for wireless systems that operate in a composite radio context. Aspects addressed are the requirements, high-level platform design, functionality of the components that conduct monitoring, resource brokerage, service management, and network resource optimization. Indicative results are presented and concluding remarks provided.     

Resource management and quality of service in third generationwireless networks

The third generation networks and services present opportunities to offer multimedia applications and services that meet end-to-end quality of service requirements. The key parts of the standards are already in place, and limited 3G services have already been turned on. While the evolution to 3G occurs, many operators will implement 2.5G interim solutions for a good period of time. We discuss the various evolution scenarios from the present 2G networks to 3G networks. Then we present the UMTS QoS architecture and its requirements, followed by a discussion on QoS in 3G air interfaces, radio access network, and core network     

Wireless Internet access for mobile subscribers based on theGPRS/UMTS network

With the advent of IP technologies and the tremendous growth in data traffic, the wireless industry is evolving its core networks toward IP technology. Enabling wireless Internet access is one of the upcoming challenges for mobile radio network operators. The General Packet Radio Service is the packet-switched extension of GSM and was developed to facilitate access to IP-based services better than existing circuit-switched services provided by GSM. We illustrate how a visited mobile subscriber on a GPRS/UMTS network can access his/her home network via the gateway GPRS support node (GGSN). We also propose some implementation ideas on wireless Internet access for a remote mobile subscriber based on a GPRS/UMTS network     

Topological planning and design of UMTS mobile networks: a survey

In this paper, we present a literature review on the topological planning problem of third generation (3G) cellular networks based on the universal mobile telecommunications system (UMTS) standard. After describing the UMTS architecture, we introduce each subproblem and present major works that have been done. The cell, the access and the core network planning problems have all been considered as well as a more global approach (when more than one subproblems are considered simultaneously). Both planning and expansion algorithms are also included in this review. The goal of this paper is to present and classify the different research works that have been done so that it can be used as a starting point for future research on topological design of UMTS networks. Copyright © 2008 John Wiley & Sons, Ltd.     

第三代移动通信网的技术倾向

简述未来的第三代移动通信网ＩＭＴ ２０００准备提供高速数据业务的基本设想,即在移动核心网中加设“通用分组无线电业务”,以便连往Ｉｎｔｅｒｎｅｔ。进而说明空中接口倾向于使用“宽带码分多址”和“时分双工”的制式,而在无线电接入网中加设“无线电网络控制器”,该控制器与基台之间则利用异步转移模式及其新型适配层的交换技术和信令规约。     

Development of Mobile Communications Systems Beyond Third Generation

Second generation mobile radio systems have been successfully deployed worldwide. These systems are evolved to higher data rates and packet transmission. Third generation mobile radio systems will be initially deployed in 2001 and 2002 in different regions of the world. Advanced multimedia services are under development and first services are already being offered in second generation systems. Due to the megatrend of the rapid growth of Internet type services packet oriented traffic is exceeding circuit switched traffic. Therefore, communication systems will be developed and optimized for packed oriented traffic. This paper presents a vision of a system beyond third generation mobile communications, which comprises a combination of several optimized access systems on a common IP based medium access and core network platform. These different access systems will interwork by horizontal and vertical handover, service negotiation and global roaming. The different access systems are allocated to different mutually complementing cell layers with respect to cell size, coverage and mobility to provide globally optimized seamless services to users.     

Toward a generic "always best connected" capability in integrated WLAN/UMTS cellular mobile networks (and beyond)

The next generation of mobile communications, broadly referred to as 4G, is based on a heterogeneous infrastructure comprising different wireless (and wired) access systems in a complementary manner. 4G mobile users enjoys seamless mobility and ubiquitous access to applications in an always best connected (ABC) mode that employs the most efficient combination of available access systems. The ongoing commercialization of 3G cellular mobile networks and their upcoming enhancement with WLAN radio access provides a wireless platform suitable for the introduction of "ABC" capabilities. We analyze the implications of the "ABC" vision in a UMTS/WLAN network context, and reveal important issues that arise. Further on, we identify major requirements, point out the limitations of current UTMS/WLAN standards from an ABC viewpoint, and discuss key enabling technologies and research efforts. We formulate a generic application model for an ABC capability in the interworked UMTS/WLAN architecture and analyze its complexity proving that, in principle, being always best connected translates to a family of NP-hard problems. To complement our analysis, we present an object-oriented design of a real-time UML model for an ABC mobile system. Finally, we summarize the advantages of our ABC model and provide directions for future work.     

GPRS与UMTS系统网络接入安全机制的比较与研究

详细介绍了GPRS与UMTS系统的网络接入安全机制,分析了GPRS系统中存在的安全漏洞及UMTS较GPRS在网络接入安全性方面的改善,最后分析了UMTS系统中存在的安全缺陷。     

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.     

CAC-RD: an UMTS call admission control

The third wireless network generation (3G) aims to provide fast Internet access with quality of service (QoS) guarantees, especially to multimedia applications. UMTS (Universal Mobile Telecommunication System) is a kind of 3G networks. To provide QoS, the network must use an efficient admission control mechanism. This mechanism needs to prioritize network access to critical classes of applications. This work proposes an UMTS admission control mechanism, called CAC-RD (Call Admission Control—based on Reservation and Diagnosis). It is based on network diagnosis and on channel reservation for handovers. These techniques are associated with new calls blocking when the network reaches utilization thresholds. CAC-RD is a tool that prioritises handovers and conversational applications. The main CAC-RD goals are the handovers blocking reduction and the acceptable performance levels guarantee. Simulation results show that the CAC-RD channel reservation and the diagnosis techniques associated with the intrinsic network signal power control effectively reduces blockings while guarantying performance levels. Due to computational resource limits, simulations cannot answer related to admission control in big networks with thousands of users. This work presents a method to extrapolate scientific questions like CAC’s behavior with thousands of users and many antennas. An artificial neural network approach for CAC-RD in UMTS 3G networks is presented as an extension of the work.