Emerging mobile and personal communication systems

The market demand for wireless communications has been demonstrated by the rapid growth of different second-generation wireless technologies that are optimized for particular applications and environments. Obvious examples include: digital cellular systems like GSM, ADC, PDC,and DCS1800 for widespread vehicular and pedestrian services, and cordless telecommunication systems based on CT2, DECT, and PHS standards for residential, business, and public cordless access applications. Efforts are also underway to consolidate the various radio environments and applications under a single standard for third generation wireless, i.e., FPLMTS. In the area of personal mobility, with the recent availability of “personal” numbers in various countries (e.g., 500 numbers in the United States), many fixed network operators are starting to offer such personal mobility services as “personal number service” and “number portability”. These services represent initial stages of full personal mobility that will be provided by UPT in both wireline as well as wireless environments. The expected heavy demand for PCS in the United States and the underlying market/regulatory forces are driving the standardization and business activity. A number of air interface standards for the 1900 MHZ PCS band are being considered, which are based on TDMA, CDMA, and FDMA technologies singly or in combination. Many are variations of existing digital cellular and cordless telecommunications technologies. PCS networking standards are also being developed; both for standalone systems and for systems that will utilize public switched network capabilities     

Low-tier wireless local loop radio systems. I. Introduction

The article provides the results of a set of analyses conducted to compare two major radio technologies, DECT/PWT-E and PACS, for their suitability in the local loop in the United States to provide voice and data services. DECT, digital enhanced cordless telecommunications, is a radio interface standard developed in Europe mainly for indoor wireless applications and being promoted lately for wireless local loop applications as well. PWT, personal wireless telecommunications, is a DECT-based standard developed by the TIA in the United States for the unlicensed PCS applications. PWT-E, enhanced, is the version that is suitable for the licensed PCS applications. PACS, personal access communications systems, is a total system standard (i.e. radio interface and associated network infrastructures) developed in the United States for licensed PCS applications. (PACS-UA and PACS-UB are the standards for the unlicensed PCS applications.) For the wireless local loop (WLL), we make an assumption that the radio technologies operating in the licensed PCS spectrum are more suitable to provide a quality of service that is expected traditionally from a local exchange company (LEC). Therefore, this article focuses on the PACS and PWT-E, rather than PACS-UB and PWT. Also note that the article focuses on the North American version, PWT-E, rather than the European version, DECT. It provides an introduction to the PACS and PWT technologies     

Does the wireless industry really need all of these standards?

There is an ongoing proliferation of standards impacting the development of wireless technology and products. Looking at the large collection of existing and emerging standards supporting the wireless systems that are available on the market, one has to wonder whether the wireless community really need all of these standards. After examining both why and how standards are created, we can say that the more standards available, whether they are competing or complementary, the greater the choices for the market, and thus the greater the chance the market will have access to the best technologies to suit its need. The proliferation of standards in the long term fosters competition, lowers prices to consumers, and allows for innovation in other areas     

Personal communication systems (PCS)

Personal communication systems (PCS) represent a rapidly growing and increasingly important segment of the telecommunication industry. The goal of PCS is to provide truly personal, cost-efficient communication services to users through portable handsets. In this paper, we present a survey on the research and development in PCS, emphasizing several important aspects such as the PCS concept, service requirements, system architecture, operation, and management. Some ongoing field trials are described as well. We focus on the wireless and the mobility-related features of PCS, discuss their impact on the system design and performance, and provide an overview of different technology choices     

PCS mobility support over fixed ATM networks

As broadband multimedia services and wireless services become popular, there is growing interest in the industry to support ATM over a wireless link, and wireless access to fixed ATM networks. We focus on the internetworking of PCS and ATM networks, in which the air interface remains one of the PCS standards and the backbone is an ATM network with mobility support. It is desirable to minimize the impact of the internetworking and mobility support on the existing/emerging PCS and ATM specifications. A network architecture, a protocol reference model, and signaling protocols for PCS mobility support over fixed ATM networks are described. They are compared against other implementation alternatives and the trade-offs are discussed. Some performance results of the proposed architecture are also presented     

Mobility management in next-generation wireless systems

This paper describes current and proposed protocols for mobility management for public land mobile network (PLMN)-based networks, mobile Internet protocol (IP) wireless asynchronous transfer mode (ATM) and satellite networks. The integration of these networks will be discussed in the context of the next evolutionary step of wireless communication networks. First, a review is provided of location management algorithms for personal communication systems (PCS) implemented over a PLMN network. The latest protocol changes for location registration and handoff are investigated for mobile IP followed by a discussion of proposed protocols for wireless ATM and satellite networks. Finally, an outline of open problems to be addressed by the next generation of wireless network service is discussed     

A new cellular architecture based on an interleaved cluster concept

Personal communications services (PCSs) and future broad-band wireless systems are and will continue to be driven mainly by three challenging objectives: high-spectrum reuse efficiency, high-quality channels, and low infrastructure costs. We propose a new interleaved narrow-beam trisector cell (INBTC) architecture with a newly developed interleaved channel assignment (ICA) scheme to achieve these three objectives. Originating from the ICA scheme, we introduce the concept of interleaved cluster, within which a channel set can be assigned more than once. The INBTC architecture with interleaved clusters can enhance the performance of cellular/PCS systems from several perspectives. We demonstrate that to achieve high-spectrum efficiency, specifically in the range of reuse factors N=2-7, the INBTC system improves 3-5 dB at the 90th and 95th percentiles of signal-to-interference ratio (SIR) compared to conventional cellular systems. For a typical cellular environment, with a shadow fading standard deviation σ=8 dB and an SIR requirement of 17 dB at the 90th percentile, the INBTC system can increase system capacity by 75% over current systems. Because the INBTC architecture can utilize the base-station equipment of current cellular/PCS systems, implementing it should be simple and carry no attendant infrastructure costs. Hence, the proposed INBTC system (the cell layout plus the channel assignment scheme) has significant potential value in future cellular/PCS systems, as well as in broad-band wireless applications     

Challenges in the migration to 4G mobile systems

With the rapid development of wireless communication networks, it is expected that fourth-generation mobile systems will be launched within decades. 4G mobile systems focus on seamlessly integrating the existing wireless technologies including GSM, wireless LAN, and Bluetooth. This contrasts with 3G, which merely focuses on developing new standards and hardware. 4G systems supports comprehensive and personalized services, providing stable system performance and quality service. However, migrating current systems to 4G presents enormous challenges. In this article, these challenges are discussed under the headings of mobile station system, and service aspects. Proposed solutions to the research problems in each aspect are also examined.     

Wireless LANs and mobile networking: standards and futuredirections

The emerging widespread use of wireless LAN systems together with the users' desire for such systems to interoperate has created a requirement for standards. Many standards bodies are currently defining standards for wireless systems that relate to different layers of the networking protocol stack. Of these, two influential physical and data link layer standards, IEEE 802.11 and the European HIPERLAN, are described. The article then considers the network layer by discussing extensions that are being made to the widely used Internet protocol (IP) to deal with mobility (wired or wireless). The final standards that are discussed relate to wireless link management. The article concludes by speculating on future directions for wireless LAN systems     

Recent advances in cellular wireless communications

Testimonies of “wireless catching up with wireline” have begun. An information superhighway system is envisioned to fulfill the plethora of demand for wireless communications and the need for multimedia networks with multiservice requirements. The revolution in this technology will eventually free us, as communication users, from being tied down to a particular fixed location in a telephone network to person-to-person communications, via pocket-sized terminals, at an affordable price. This article briefly surveys the state of the art, standards, and technological growth experienced in mobile cellular (terrestrial and satellite) communications since the days of the ingenious inventions of Alexander Graham Bell and Guglielmo Marconi, over a century ago. Subsequently, we describe some emerging technological trends that can improve the capacity of third-generation systems and future outlooks for PCS networks in the next millennium     

个人通信系统中的一种移动用户登记认证协议

假冒和窃听攻击是无线通信面临的主要威胁。在个人通信系统中,为了对无线链路提供安全保护,必须对链路上所传送的数据/话音进行加密,而且在用户与服务网络之间必须进行相互认证。近年来,人们在不同的移动通信网络(如GSM,IS-41,CDPD,Wireless LAN等)中提出了许多安全协议。然而,这些协议在个人通信环境中应用时存在不同的弱点。本文基于个人通信系统的双钥保密与认证模型,设计了用户位置登记认证协议;并采用BAN认证逻辑对协议的安全性进行了形式化证明,也对协议的计算复杂性进行了定性分析。分析表明,所提出的协议与现有的协议相比具有许多新的安全特性。     

Transceiver Architecture Selection: Review, State-of-the-Art Survey and Case Study

Realizing multi-standard transceivers with maximum hardware reuse amongst the given standards is of great importance to minimize the manufacturing cost of emerging multi-defined service wireless terminals. A well architecture in conjunction with a reconfigurable building-block synthesis is essential to building formulate such a kind of tunable transceiver under a wide range of specifications. In this paper, we present both fundamental and state-of-the-art techniques that help selecting transceiver architecture for single-/multistandard design. We begin by reviewing the basic schemes and examining their suitability for use in modern wireless communication systems (GSM, WCDMA, IEEE 802.11, Bluetooth, ZigBee and Ultra Wideband). The justifications are confirmed with the state of-the-art choices through a survey (with 100+ references) of the most frequently used receiver and transmitter architectures reported in 1997 to 2005 IEEE solid-state circuit forums: ISSCC, CICC, VLSI and ESS-CIRC. State-of-the-art techniques for multistandability are analyzed through careful case studies of a cellular receiver for GSM/DCS/PCS/WCDMA, and several WPAN/WLAN transceivers for Bluetooth and IEEE 802.11a/b/g. They disclose, on the architecture and circuit levels, many ideas that have successfully inspired the recent development of wireless circuits and systems     

Design trade-offs in cellular/PCS systems

With the increasing demand for all kinds of wireless access services, including cellular/PCS, wireless local loop, and broadband access, the system architects will have opportunities to design new communication systems, not necessarily based on existing wireless standards. In the design of wireless communication systems, there are usually multiple objectives such as low cost, small size, high reliability, and large capacity. The system architect would need to study the trade-offs among different combinations of modulation, coding, multiple access, and antenna techniques to determine the best design. In this tutorial we focus on the trade-offs between user bandwidth and multi-user interference in order to maximize the system capacity. The design trade-offs are depicted on a B-γ₀ plane. Where B is the user bandwidth and γ₀ is the carrier-to-interference ratio (C/I). For F/TDMA and CDMA systems, the author first shows that the contours of equal system capacity are straight lines with different slope's depending on the propagation environment, and the capacity decreases for increasing B and γ₀. Then as feasible solutions, the author plots the different combinations of modulation and coding with diversity to satisfy a certain quality of service in a multipath environment. The best design is obtained by moving a line with a certain slope from the lower left corner in the B-γ₀ plane until it touches the first feasible solution. From these plots we can see that, for example, while 1/2-rate channel coding is the best choice for F/TDMA systems, 1/3-rate is better for CDMA systems     

Satellite systems for personal communications

A number of industry groups are planning to construct satellite systems that will provide a personal communications service (PCS) (typically voice, data, and fax) to users over small, hand-held, cellular-type telephones. Some of these systems (e.g., Iridium and Globalstar) will be constructed using satellites in low Earth orbit. Two (Ellipso and ICO) will employ medium Earth orbit (3-8-h period), and still others (ACeS and Agrani) will operate from geostationary altitude. The origin and evolution of mobile satellite communications is discussed first, including the Inmarsat system and several land-based mobile satellite systems in operation. The rival approaches to the PCS market are then described, and some of the technical challenges inherent in each are indicated. This paper concludes with speculation on the factors influencing the likelihood of business success for the various PCS systems     

SEMI E133—The Process Control System Standard: Deriving a Software Interoperability Standard for Advanced Process Control in Semiconductor Manufacturing

The process control systems (PCS) SEMI Standard E133 facilitates the integration of PCS into current and future fabs. The standard focuses on defining the portion of ldquointerface Brdquo associated with communication with and between components of PCSs. Specifically, the scope of the standard is the functional groups of run-to-run (R2R) control, fault detection (FD), fault classification (FC), fault prediction (FP), and statistical process control (SPC). The standard specifies PCS interfaces (which utilize ldquointerface Brdquo) that will enable these functional groups to interact effectively and share data among themselves and with the other interdependent factory systems, including systems within the process equipment. Key requirements driving the standard specification include the move to service-oriented and event-driven architectures and a need to define PCS capabilities from an input/output (I/O) perspective along functional boundaries defined by commercial applications. The developed standard addresses these requirements and specifies: 1) the capabilities of all five functional groups; 2) a comprehensive I/O interface data model; 3) an XML representation of that data model (E133.1); 4) a set of common services and behavior classes; 5) extensions of the I/O structure and behavior for each functional group; and 6) an application note that provides an example of PCS integration with equipment data acquisition (EDA) data collection. XML, R2R control, and FD implementation examples illustrate that the standard addresses these requirements, with the FD example further illustrating compatibility with EDA ldquointerface Ardquo standards. The standard to date has mature R2R control and FD specifications with key PCS users and providers indicating that they are using the standard extensively.     

An overview of the standardisation in the area of the broadband fixed wireless access

The broadband fixed wireless access systems will be subject to an increasing development during the next years; these systems will allow to offer the subscriber a full set of services, from the conventional narrow band applications up to the emergent broadband services like Internet access, or leased lines. This rapid growth has carried several initiatives in the telecommunications standardisation bodies, like ETSI in Europe, IEEE in North America, or ITU at international level. These initiatives resulted in the creation of ad hoc groups, for instance the BRAN/Hiperaccess project of ETSI, the IEEE 802.16, or the jrg 8A-9B in ITU standards resulting from this activity are expected in 2000/2001. In parallel to this standardisation activity it appeared necessary to designate, or at least to recommend, dedicated frequency bands for fixed wireless access (fwa) or multimedia wireless systems (mws) applications. In order to satisfy this need the regulation authorities, especially the CEPT in Europe, are preparing decisions and recommendations which are expected to favour a certain level of harmonisation in the use of the spectrum by fwa or mws systems.     

平流层通信及相关技术

蜂窝和个人移动通信系统（ＰＣＳ）需要大量广布的天线塔、基站、有线或微波线路，卫星通信系统地面设施相对较少，但ＧＥＯ系统的用户终端笨重且昂贵，信号时延大；ＭＥＯ和ＬＥＯ卫星相对于地面的快速运动使系统的构成和控制复杂化，并且卫星发射和维护费用高，高空航空平台（ＨＡＡＰ）无线通信系统（即平流层通信）实为折衷方案，本文讨论了此类通信系统的特点和实现的可能性。     

无线宽带接入技术浅析

在无线数据通信系统中,宽带无线接入获得了广泛的关注,对于宽带无线接入技术的选择将会影响未来通信市场的走向。本文对比研究了WiMAX,Wi-Fi,LTE三种无线接入技术遵循的标准和优缺点,对以上三种无线接入技术进行总体性的比较研究,并对未来无线宽带接入技术的发展进行了展望。     

Teletraffic considerations for widespread deployment of PCS

To offer personal communication services (PCS) to large segments of the population, sophisticated digital radio access techniques and extensive use of “Advanced Intelligent Network” services of public wireline networks will be required. To accommodate wireless access on such a wide scale, a broad range of challenging new teletraffic problems will need to be solved. In this article the authors give a brief, high-level overview of some of the important teletraffic issues that they believe will need to be addressed to support widespread deployment of PCS. Much more work is needed in order to refine our understanding of these issues, to prioritize specific problems, and to solve them. The purpose of this article is not to provide an exhaustive list of all PCS teletraffic issues, but rather to stimulate discussion of these problems     

Direction for element managers and network managers

In the past, each new network element of a wireless network had a corresponding management system to provide management capabilities. Each of these management systems had a different user interface, employed a different computing platform, and typically managed one type of network element. The total O&M system was the sum of these independent resources, consuming partial solutions that made network management tasks inefficient, complex, time consuming, and expensive to administer. Large operations costs borne from these inefficiencies were once buffered by large cellular operator profits. With the introduction of PCS, operators became extremely cost conscious and sought to eradicate these large costs. Additionally, wireless service providers moved into a mixed vendor environment, where network elements manufactured by several vendors are used, so they could no longer afford different management systems for each network element. In today's environment, a wireless service provider who can provide better service quality at the lowest price will be the ultimate winner. The key to providing better service quality at the lowest price is to have efficient network management. As the wireless industry strives to push wireless prices on a par with wireline, the necessity for reduced network operation and management costs takes on increasing importance