A radio system proposal for widespread low-power tetherlesscommunications

It is suggested that low-power digital radio as an access technology could be integrated into a local exchange network to provide a ubiquitous personal communications network (PCN). High-quality tetherless communications services that could be provided by such an exchange-network-based PCN are described. A possible low-power exchange access digital radio system for providing these exchange-network based PCS services is discussed. The radio system uses a spectrum-efficient time-division multiple-access (TDMA) architecture made possible by advanced digital signal processing techniques. Control of the frequency reuse system is described, and frequency spectrum needs are indicated     

个人通信网和个人通信服务

作为第三代移动通信的创新概念“个人通信”被提出以来，个人通信网和个人通信服务从定义、理论、技术、设备等各方面得到不断发展和明显进步，得到全世界通信学界的极大重视，本文依据个人通信网的定义和现实发展，对个人通信网的研究发展方向，技术重点，实现个人通信服务所需求的功能和应用前景等进行讨论。     

Polling deregistration for unlicensed PCS

The FCC has allocated the spectrum between 1850-1910 and 1930-1990 MHz for licensed personal communications services (PCS) and the band between 1920-1930 MHz for unlicensed PCS (UPCS). This paper describes a polling deregistration protocol for a wireless access communications network which would support interoperability between licensed personal communications services (PCS) and unlicensed-PCS (UPCS). We show how the protocol can be efficiently implemented in the personal access communications system (PACS) for licensed PCS and in the PACS-Unlicensed Version B (PACS-UB). An analytical model is proposed to analyze the performance of the polling protocol. A cost function is derived, which can be used to estimate the optimal polling frequency     

Spread spectrum technology: a solution to the personalcommunications services frequency allocation dilemma

The spectrum allocation problems posed by the establishment of personal communications services (PCS) are discussed, and some conclusions are drawn from the recent experience of licensing personal communications networks (PCNs) in the UK. A proposal for spectrum sharing is presented, focusing on the criteria to be met and the use of code-division multiaccess technology for its implementation     

Personal communications services: the next technological revolution

The US Federal Communications Commission (FCC) has issued a Notice of Inquiry (NOI) to consider whether to allocate frequencies for personal communications services (PCS), the particular PCS offerings to authorize, the technical standards that licensees should follow, and the regulatory policies tha should govern PCS operations, including who may be eligible for PCS licenses. An overview is given of the reaction that the NOI has generated and the critical threshold decisions that the FCC will be making. These are discussed in the context of the need for PCS spectrum allocation and industry structure issues     

The cost structure of personal communication services

The costs of constructing and operating personal communications service (PCS) systems are examined to assess the potential spectrum requirements of these services. The cost model developed for this task estimated the costs of building and operating a new PCS network, as well as the costs of providing PCSs using existing infrastructure such as the telephone, cable television, and cellular telephone networks. Based on these estimates, this study finds economies in using each of these infrastructures. Moreover, no justification exists, based on the characteristics of the cost functions, for limiting the number of licenses to the PCS market for licensing of 20 MHz of spectrum or more, and 20 MHz may be a sufficient spectrum allocation for implementing low-cost PCS systems     

Global development of PCS

A brief survey of international efforts to address spectrum and incumbency issues and implement new personal communications services (PCS) is presented. Worldwide frequency allocations agreed to in the 1992 World Administrative Radio Conference (WARC 92) are discussed. The development of personal communication services in European, Asian, and North American countries is reviewed     

Heterogeneous personal communications services: integration of PCSsystems

Personal communications services (PCS) are being introduced to offer ubiquitous communication. In its first phase PCS consists of a plethora of systems that address cellular, vehicular, cordless phone, and a variety of other services. The integration of these different systems is referred to as “heterogeneous PCS (HPCS)”. We describe the various PCS systems available and address in detail the issue of PCS systems integration. Key implementation issues for integrating PCS systems are defined and discussed     

Personal communications networks bridging the gap between cellularand cordless phones

Today's cellular radiotelephone systems currently serve some 12 million subscribers but at average costs of $70/month for service, cellular remains a business, not a consumer, service. On the other hand, cordless phones are already a consumer product in over 40% of US households and annual sales of new cordless phones are already greater than sales of regular corded phones. Personal Communications Networks (PCN) providing Personal Communications Services (PCS) are designed to bridge the gap between expensive public cellular and private cordless services. In this paper we explore PCN/PCS topics including: a definition of the service, identification of the underlying technologies, and discussion of tradeoffs between the technologies     

Broadband CDMA for personal communications systems

Multipath propagation in a broadband CDMA environment is described. A propagation model for broadband spread-spectrum signals is presented. Experimental results relating to the sharing of the band by fixed service microwave users and mobile personal communications network (PCN) users are discussed. Field tests indicate that PCN systems can provide high-quality communications when sharing the spectrum with fixed-service microwave systems in suburban and urban areas     

The FCC on personal wireless

In a landmark decision announced in September 1993, the Federal Communications Commission (FCC) outlined the rules to be followed in the United States by the up-and-coming personal communications services (PCS) industry. This industry is structuring itself to offer new mobile and portable wireless services in direct competition to those that already exist, such as paging, cellular, and private radio services. The FCC's decision was essential in paving the way. It allocated 160 MHz of radio spectrum, determined the size of the geographic service areas, and laid down eligibility requirements for the service providers. It also outlined broad technical standards and construction requirements, and established guidelines for evaluating the exposure of users to the radio-frequency (RF) radiation emitted by PCS devices. This action heralds auctions of the first licenses in 1994     

Integrated Services over ATM/MAN-Based Personal Communication Networks

IEEE 802.6 metropolitan area networks (MANs) providean efficient architecture for supporting wirelesspersonal communication services (PCSs) overmetropolitan areas by interconnecting wireless basestations into personal communication networks (PCNs).They also serve as peripheral gathering networks totransport PCS traffic over a wide area broadbandintegrated services digital network employingasynchronous transfer mode (ATM), enabling integrationof PCNs in different cities into a global PCN. Bycombining the various access methods and employing adynamic bandwidth integration scheme, a MAN canfunction as a powerful distributed switch forintegrating different types of local traffic.Simulation results are presented to illustrate theadvantages of the integration scheme. To provideubiquitous PCS, we also propose a simplesuffix-dialing method for integrating telephone, fax,paging and email services over the ATM/MAN-based PCNsusing a single personal telecommunication number. Withthis method, the current practice of printing a longlist of phone numbers on one's business card will nolonger be necessary.     

Performance of personal access communications system-unlicensed B

The FCC has allocated the band between 1920 MHz and 1930 MHz for unlicensed personal communications services (UPCS) using isochronous or circuit operation. The UPCS spectrum is between the licensed PCS spectrum bands of 1850-1910 MHz and 1930-1990 MHz. Terminal interoperability in both the UPCS spectrum on private indoor wireless systems and the licensed spectrum on public PCS systems is desirable and encouraged by the FCC. This paper presents a port channel assignment process for the personal access communications system-unlicensed B (PACS-UB) which abides by the FCC etiquette for UPCS and discusses the corresponding uplink and downlink performance. Uplink power control is employed to improve the uplink performance. PACS-UB has a high degree of commonality with licensed PACS to permit economical licensed/unlicensed terminals and common network services. The results of our simulation show that, at 1% to 2% blocking probability, 99% of downlink local-mean signal-to-noise plus interference ratio (SINR) values are above 17 dB for a 10 to 20 m port separation. For a three-dimensional office environment, the uplink limits the SINR performance, however, with uplink power control, a 5.5 to 7 dB improvement in the uplink SINR can be achieved even for high traffic load     

Satellite systems for personal communications

A number of industrial groups are planning to construct satellite systems to provide personal communications services (typically voice, data, and fax) to users who will employ 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 (Odyssey and ICO) will employ medium Earth orbit (six-hour 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 personal communications services (PCS) market are then described, and some of the technical challenges inherent in each are indicated. The paper concludes with speculation on the factors influencing the likelihood of business success for the various PCS systems     

Wireless loops: What are they?

Several loop applications of wireless technology are aimed at reducing the cost of deploying communications services ranging from telephone to wideband video. In these applications, wireless links replace a portion of a wireline loop from a central location (a central office or cable headend) to a subscriber. The replacement of labor-intensive wireline technology by complex mass-produced integrated electronics in wireless transceivers is projected to reduce the overall cost of the resulting loop. These wireless loop applications attempt to provide existing communications services or small modifications to existing communications services. A different interpretation of a wireless loop makes use of low-power digital radio technology to provide the last thousand feet or so of a loop. Low-power low-complexity wireless loop technology in small base units can be integrated with network intelligence to provide the fixed-infrastructure network needed to support economical personal communications services (PCS) to small, lightweight, low-power personal voice and/or data communicators. Low-complexity communicators can provide many hours of “talk time” or data transmission time and perhaps several days of standby time from small batteries (≤ 1.5 oz). Because this application of wireless loop technology can reduce the inherent costs in several parts of a wireline loop, it has the potential to provide convenient widespread PCS at less costs than providing telephone services over conventional wireline loops. This low-power wireless loop application does not fit into any existing communications system paradigm. Wireless technology with tetherless access and wide-ranging mobility, e.g., the personal access communications system (PACS), does not fit the accumulated wisdom of the wireline telephony paradigm. It also does not fit the paradigm of existing cellular radio that has sparsely distributed expensive cell sites, and it is not targeted at fixed video services as is wireless cable. Because a significant change in thinking is required in addressing this new low-power low-complexity widespread wireless loop paradigm, its large economic advantages and service benefits have not yet been embraced by many of the existing communications providers, who appear to be more comfortable pursuing the better-known paradigms of video using wireless cable, or of cellular radio in the guise of high-tier PCS, or in the guise of rapid economical deployment of telephone services in developing nations. This paper discusses the inherent economic advantages and service benefits of low-power low-complexity wireless loop technology integrated with network intelligence aimed at providing economical low-tier PCS to everyone.     

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     

The ideal communications service [PCN]

The development of personal communications network (PCN) technology in the United Kingdom is reviewed. It is argued that the perceived benefits of PCN, smaller handsets, improved communication quality, and increased capacity of the PCN technology, as compared with the competing cellular networks, are expected to give the personal communications concept mass-market appeal. Future technological developments for PCNs and issues concerning PCN development, including competition, pricing strategy and penetration, market confusion, and technological limitations, are discussed     

A CDMA-distributed antenna system for in-building personalcommunications services

To investigate applications of spread spectrum code division multiple access (CDMA) technology to in-building personal communications services (PCS), comprehensive studies have been conducted for a CDMA PCS distributed antenna system in the 1.8 GHz band. The CDMA PCS distributed antenna system was set up with three nodes, each having two time-delayed elements, in a Qualcomm two story office building in San Diego. This paper presents measurement and modeling results on coverage, voice quality (frame error rate), reduction of transmit power, and path diversity for the in-building CDMA PCS distributed antenna system. Wideband CDMA signal coverage was predicted by using a ray tracing tool to find optimum placement of the distributed antennas. Using three nodes mounted in the ceiling space between the first and second floors, with each active element transmitting at -5 dBm in the system, the ray-tracing prediction shows good signal coverage in both floors of the building. The prediction results are confirmed by measurements at numerous discrete points with a standard deviation of 3.3 dB. Measurements using various combinations of number of nodes and delay elements showed significant time and path diversity advantages for the CDMA-distributed antenna system in indoor radio environments. Trade-offs between diversity gain and self-interference due to uncaptured finger energy in fringe areas are discussed     

A portable multimedia terminal

A personal communications system (PCS) that centers on integration of services to provide access to data and communications using a specialized, wireless multimedia terminal is described. The possible applications and support systems for such a terminal are outlined. Several of the major design issues behind portable multimedia terminals, including spectrally efficient picocellular networking, low-power digital design, video data compression, and integrated wireless RF transceivers, are discussed. It is argued that optimizing performance in each of these areas is crucial in meeting the performance requirements of the overall system and providing a small, lightweight terminal for personal communications