Showing papers on "Wi-Fi array published in 1991"

Trends in cellular and cordless communications

Abstract: The evolution of wireless information networks is traced from the present first generation systems to next century's third generation. The third generation is envisioned as a unified wireless access replacing the diverse and incompatible second-generation networks with a single means of wireless access to advanced information services. Four issues are examined: the goal a network is designed to achieve, network architecture, radio transmission technology, and the control channels that make it possible for wireless terminals and the remainder of the network to coordinate their operations. In the framework of these issues, present networks are described; the properties of four second-generation networks, GSM, IS-54, CT2, and DECT, are cited; and early work in progress at the Rutgers WINLAB is described. The latter is a packet-reservation multiple-access scheme that can be viewed as a combination of TDMA and slotted ALOHA. >

Access protocol for a common channel wireless network

Abstract: An access protocol and method for a common channel wireless network addresses the functions needed in large scale wireless local or premises area networks where the user stations are or may include battery-powered portable computers and telephones either fixed or moving. The function provided is setup and rapid transfer of data packets or of virtual circuits by segmental packet transmission. Microwave radio frequencies are assumed to be the primary transmission mode, however optical propagation is also a usable medium.

Remote controlled electronic presentation system

Abstract: An electronic presentation system is presented utilizing a wireless remote for controlling a digital computer, one or more display or storage/playback devices and an audience response system. A Terminate and Stay Resident (TSR) program within the digital computer manages the wireless remote. The digital computer running the TSR program enables the wireless remote to operate any applications program, as well as to use the computer to add spontaneously certain special effects to the presentation and to control an audience response system. In addition, the computer downloads into the wireless remote control, via a wireless communications link, data commands and signalling parameters such as modulation scheme and communications protocol with which to enable the wireless remote to generate the correct signalling to operate predefined display or storage/playback device.

Software technology for wireless mobile computing

Abstract: Some of the possibilities and requirements for mobile computing on wireless local area networks (LANs) are discussed from the systems software viewpoint. The design of the Student Electronic Notebook (SEN) is sketched to provide a partial catalog of problems in building a real system for wireless mobile computing. This project was initiated to investigate the potential of wireless mobile computing to reshape education. Some of the key directions for research in software technology for wireless, mobile computing are examined. Some of the authors' experience with wireless LANs is related. >

Enabling technologies for wireless in-building network communications-four technical challenges, four solutions

Abstract: A wireless in-building network is proposed, raising the possibility that at least part of the hard-wired infrastructure may no longer be needed. This wireless network is based on the refinement of cellular radio techniques in the 18 GHz range. The basic set of problems this technology addresses is described. These are the minimum performance and features required of a viable in-building wireless technology, the range of options available in selecting a design approach for such a system, and the technical problems that were faced in developing a microcellular wireless in-building system. >

System and method for linking wireless local area networks

Abstract: A wireless local area network (LAN) station and method for operating the same. The station has a number of antennas for communicating with a similar number of LANs, respectively. Transmissions from one antenna are blocked when the other antenna is receiving RF signals.

Variable partition duplexing for wireless communications

Abstract: A scheme for almost doubling the capacity of wireless communication systems by speech activity detection is proposed. This scheme is called variable partition duplexing (VPD). The key observation is that in conversational speech, except for small overlaps, only one of the two parties is talking at any given time. VPD attempts to use this observation to advantage by dynamically varying the bandwidth assigned to the two parties in a TDMA (time division multiaccess) system. >

Personal communications network

Abstract: Wireless access and egress gives the service providers an added flexibility for personal comm unications which deals with linking people rather than their telephones. Currently, personal communication needs are partially satisfied by several wireless services including cellular mobiles, pagers, satellite and cordless telephones. Based on emerging concepts, architectures and standards, enhancements to existing wireless services and several new services are now under consideration; the new services include digital cellular systems, and wireless PBX and CENTREX services. Globally, each of these services can be based on different standards and have unique characteristics. This may prevent the ubiquitous offering of a 'truly' global wireless services, Personal communications network (PCN) is seen as a vehicle to offer global services. This paper discusses the PCN concept, architecture and evolution.