Low-tier wireless local loop radio systems .2. Comparison ofsystems

For pt.1 see ibid., no.3, p.84 (1997). 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 to provide voice and data services for customers. The authors first provide brief discussions on the Japanese Personal Handyphone System (PHS) and Omnipoint's Combined CDMA/TDMA (CCT) system as potential candidates. The authors do not currently consider them viable alternatives for local loop since the PHS is not suitable for the US environment, and the CCT system will not be available in the near future. The PACS and PWT-E systems are then compared based on their architecture, service, coverage, and operations-related capabilities. The authors also compare them in proposed deployments in Jacksonville and Miami, Florida. Finally, the authors draw some conclusions from their study     

An evaluation of quality of service characteristics of PACS packet channel

A novel application on the recently emerging wireless Personal Communications Systems (PCS) is the multimedia communication. In this paper, we evaluate multimedia communications capability and quality of service characteristics of one of the PCS standards, Personal Access Communications System's (PACS) packet channel (PPC) using simulation modeling. The performance of PPC's slot aggregation and data-sense multiple access techniques are studied by considering the downlink and uplink in a single cell and combined uplink/downlink in two cells and changing various parameters such as the number of users and certain protocol parameters. Interconnection of PPC with the Internet is discussed next. Frame rates of MPEG-1 coded images transmitted in a PACS cell as IP datagrams are determined. Handover characteristics of PPC downlink are studied by changing different parameters such as the cell size, the speed of the mobile host and time between handovers. The results clearly establish that multimedia communication on PPC is only feasible at lower bandwidths and frame rates and only a few users per cell can be supported. Careful tuning of PPC protocol parameters is required. There is one parameter whose variation gives opposite results on the downlink and uplink.     

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     

Architecture for interworking data over PCS

This article presents a new approach for wireless service providers to offer data services by taking advantage of the existing infrastructure for voice services and interworking with existing wireline-based data services. The article presents a framework: for interworking between any wireless radio system and any data application on the wireline network. The interworking is provided by a common interworking function that uses a generic interworking control protocol (ICP). Any radio system capable of using the ISDN-based C-interface and implementing ICP can take advantage of the proposed approach. ICP is a generic protocol and can be implemented using different networks. The article considers an ISDN network for the lower-layer transport of ICP. Though the article focuses on interworking with the PSTN and the Internet, the architecture also allows access to other data networks     

A wireless local loop system based on wideband CDMA technology

This article describes a wireless local loop system based on wideband CDMA technology. The unique features of CDMA technology make it a formidable alternative for fixed wireless telephone applications. The W-CDMA technology used by this WLL system is selected to provide primarily ISDN-like services and data rates to subscribers. This technology also provides a smooth transition into the third generation wireless technology. The air interface used in this WLL system is an interim TTA standard, which specifies a CDMA-based protocol operating in the 2.30-2.40 GHz band. The standard allows two types of bandwidth (5 and 10 MHz). The WLL system described in this article includes the WLL gateway switch, the radio port controller and the radio interface unit. The gateway switch connects the radio system to the PSTN and ISDN. The RPC provides concentration and control functions to a number of base stations called RPs. The RIU is comprised of the fixed units attached to the residential or commercial buildings. Also included are the radio port operation and maintenance (RPOM) unit, which is responsible for maintaining and managing the radio network elements, and the interworking function unit, which is used as a gateway to data services such as the Internet and PSPDN