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Showing papers on "Wi-Fi array published in 1999"


Book
15 Sep 1999
TL;DR: This title introduces the basic concepts and specific applications of antennas and propagation to wireless systems, covering terrestrial and satellite radio systems in both mobile and fixed contexts.
Abstract: From the Publisher: This title introduces the basic concepts and specific applications of antennas and propagation to wireless systems, covering terrestrial and satellite radio systems in both mobile and fixed contexts. Includes: Illustrations of the significance and effect of the wireless propagation channelOverview of the fundamental electromagnetic principles underlying propagation and antennasBasic concepts of antennas and their application to specific wireless systemsPropagation measurement, modeling, and predication for fixed links for macrocells, microcells, picocells, and megacellsNarrowband and wideband channel modeling and the effect of the channel on communication system performanceMehtods that overcome and transform channel impairments to enhance performance using diversity, adaptive antennas, and equalizersExamples of real-world practical system problems of communications design and operationExtensive worked examplesEnd-chapter questionsTopical and relevant information for and about the wireless communications industry.

1,367 citations


Journal ArticleDOI
01 Aug 1999
TL;DR: In this article, 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 are discussed in the context of the next evolutionary step of wireless communication networks.
Abstract: 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.

688 citations


Patent
22 Nov 1999
TL;DR: In this article, a method and system for simultaneously sharing wireless communications among multiple wireless handsets deployed in a wireless network having at least one cell site associated therewith includes a first and second wireless handset for transmitting a request for the same wireless communication.
Abstract: A method and system for simultaneously sharing wireless communications among multiple wireless handsets deployed in a wireless network having at least one cell site associated therewith includes a first and second wireless handset for transmitting a request for the same wireless communication. The wireless network then assigns a first wireless receive channel to the first wireless handset and the second wireless handset and simultaneously transmits the requested wireless communication to the first and second wireless handsets for receipt by the first wireless receive channel. If the requested wireless communication originates from a source handset, and the first and second handsets are located in direct communication proximity to the source handset, the source handset itself negotiates the common wireless receive channel for receiving the requested wireless communication.

499 citations


Patent
21 Sep 1999
TL;DR: In this paper, a system and method of exchanging information between a wireless network and an external system is disclosed, where the wireless network detects trigger events related to communications with wireless subscribers.
Abstract: A system and method of for exchanging information between a wireless network and an external system is disclosed. The wireless network detects trigger events related to communications with wireless subscribers. Certain event triggers cause the wireless system to create a message and to send that message to the external system. In response the external system may respond by sending data or information to the wireless system. The messages created by the wireless system may be in the form of query messages. The wireless system may create messages for the external system upon detection of handoff, origination, status, registration or other activity by the wireless subscriber.

484 citations


Patent
26 May 1999
TL;DR: In this article, a device for providing wireless Internet access has been described, which includes an antenna for receiving wireless queries and transmitting wireless responses, and a program for converting the wireless queries into Internet compatible protocols.
Abstract: A device for providing wireless Internet access has been described. The device includes an antenna. The antenna is for receiving wireless queries and transmitting wireless responses. The device includes a program. The program is for converting the wireless queries into Internet compatible protocols. The program is for receiving the Internet protocol formatted responses. These responses are then converted in to the wireless responses.

469 citations


Patent
26 May 1999
TL;DR: In this article, a method for effectively implementing a wireless television system comprises a wireless base station that processes and combines various program sources to produce a processed stream, which a transmitter then responsively transmits the processed stream as a broadcast output stream to various portable wireless display devices for flexible viewing at variable remote locations.
Abstract: A method for effectively implementing a wireless television system comprises a wireless base station that processes and combines various program sources to produce a processed stream. A transmitter then responsively transmits the processed stream as a broadcast output stream to various portable wireless display devices for flexible viewing at variable remote locations.

450 citations


Proceedings ArticleDOI
01 Aug 1999
TL;DR: WTCP is rate-based, uses only end-to-end mechanisms, performs rate control at the receiver, and uses inter-packet delays as the primary metric for rate control, and can improve on the performance of comparable algorithms such as TCP-NewReno, TCP-Vegas, and Snoop-TCP by up to 200% for typical operating conditions.
Abstract: Wireless wide-area networks (WWANs) are characterized by very low and variable bandwidths, very high and variable delays, significant non-congestion related losses, asymmetric uplink and downlink channels, and occasional blackouts. Additionally, the majority of the latency in a WWAN connection is incurred over the wireless link. Under such operating conditions, most contemporary wireless TCP algorithms do not perform very well. In this paper, we present WTCP, a reliable transport protocol that addresses rate control and reliability over commercial WWAN networks such as CDPD. WTCP is rate-based, uses only end-to-end mechanisms, performs rate control at the receiver, and uses inter-packet delays as the primary metric for rate control. We have implemented and evaluated WTCP over the CDPD network, and also simulated it in the ns-2 simulator. Our results indicate that WTCP can improve on the performance of comparable algorithms such as TCP-NewReno, TCP-Vegas, and Snoop-TCP by between 20% to 200% for typical operating conditions.

293 citations


Patent
John R. Hind1, Marcia L. Peters1
21 May 1999
TL;DR: In this article, a method and system for enabling wireless devices to be paired or permanently associated by a user or a network administrator is presented, which utilizes well known public key cryptography and machine unique identifiers to establish a secure channel and associate the devices with eachother.
Abstract: A method and system for enabling wireless devices to be paired or permanently associated by a user or a network administrator. The method and system utilize well known public key cryptography and machine unique identifiers to establish a secure channel and associate the devices with eachother. This is extremely useful for associating a wireless headset with a telephone or associating a wireless mouse with a computer.

249 citations


Patent
17 Dec 1999
TL;DR: An apparatus for interfacing a wireless local area network with a wide area, cellular or public switched telephone network including the function of a wireless LAN base station or access point, and a gateway as mentioned in this paper.
Abstract: An apparatus for interfacing a wireless local area network with a wide area, cellular or public switched telephone network including the function of a wireless LAN base station or access point, and a gateway. The interface may contain one or more different types of gateways, including a PSTN voice gateway, an analog modem gateway, and others. The apparatus may also include a well designed to receive the handset or mobile computer device to recharge the battery as well as to automatically transfer data when the phone or device is secured in the well.

245 citations


Patent
16 Mar 1999
TL;DR: In this article, an apparatus and method to determine a position of a mobile wireless transceiver is presented. But the method is not suitable for use in dense urban and other environments when line-of-sight to the satellites is somewhat obscured.
Abstract: An apparatus and method to determine a position of a mobile wireless transceiver. The invention merges GPS position location and wireless communication technologies to achieve a precise position location in dense urban and other environments when line-of-sight to the satellites is somewhat obscured. The inventive apparatus and method use signals from only two GPS satellites (60, 70, 80, 90) and the serving terrestrial base station. In a most general sense, the inventive method includes the steps of receiving at a base station (10) a first signal transmitted from a first GPS satellite and a second signal transmitted from a second GPS satellite. The mobile's transmitter (200) and receiver (100) are adapted to receive these GPS signals as well and transmit a third signal to the base station in response thereto. The base station (10) receives the third signal and uses it to calculate the position of the wireless unit (20).

229 citations


Proceedings ArticleDOI
19 Sep 1999
TL;DR: The paper presents an ad-hoc architecture for wireless sensor networks and other wireless systems similar to them that is energy-sensitive, distributed, scalable, and able to form a connected network rapidly.
Abstract: The paper presents an ad-hoc architecture for wireless sensor networks and other wireless systems similar to them. In this class of wireless system the physical resource at premium is energy. Bandwidth available to the system is in excess of system requirements. The approach to solve the problem of ad-hoc network formation here is to use available bandwidth in order to save energy. The method introduced solves the problem of connecting an ad-hoc network. This algorithm gives procedures for the joint formation of a time schedule (similar to a TDMA schedule) and activation of links therein for random network topologies. This self-organization method is energy-sensitive, distributed, scalable, and able to form a connected network rapidly.

Journal ArticleDOI
TL;DR: The key issues in wireless fair queuing are identified, a wireless fair service model is defined, a generic framework for designing wirelessfair queuing algorithms are presented, and solutions within this framework are explored.
Abstract: Fair queuing has long been a popular paradigm for providing bounded delay channel access and separation between flows in wireline networks. However, adapting fair queuing to the wireless domain is not a trivial task because of the unique problems in wireless channels such as location-dependent and bursty channel error. In this article we identify the key issues in wireless fair queuing, define a wireless fair service model, present a generic framework for designing wireless fair queuing algorithms, and explore solutions within this framework. Using simple examples, we show that some of the wireless fair queuing algorithms proposed in literature can achieve wireless fair service.

Patent
21 Jul 1999
TL;DR: In this paper, a system for determining the location of a mobile station is described, which includes a transceiver operating in a wireless network and a GPS receiver for obtaining ephemeris data.
Abstract: In accordance with the invention, there is disclosed a system for determining location of a mobile station. The mobile station includes a transceiver operating in a wireless network and a GPS receiver. The system includes a wireless network control system including GPS receivers for obtaining ephemeris data. The control system develops assistance information from the ephemeris data and transmits the assistance information to the mobile station via the wireless network. The assistance information represents range at a fixed location in the wireless network in proximity to the mobile station at a select time, and derivatives of the range, relative to plural select satellites in the GPS. The mobile station utilizes received assistance information for searching the composite received signals from the plural select satellites in the GPS to measure a code phase for plural ones of the select satellites in the GPS and returning the measured code phases to the wireless network control system via the wireless network. The wireless network control system computes location of the mobile station in the wireless network utilizing a fixed location and the measured code phases.

Journal ArticleDOI
TL;DR: A basic overview of MAC protocol concepts is presented, and a framework is developed on which to base qualitative comparisons, based on multimedia traffic requirements.
Abstract: This article presents a survey on medium access control protocols for multimedia traffic in wireless networks. A basic overview of MAC protocol concepts is presented, and a framework is developed on which to base qualitative comparisons. The MAC protocols covered include third-generation TDMA and CDMA schemes intended for use in a single-hop wireless system. The operation of each protocol is explained, and its advantages and disadvantages ore presented. Finally, a qualitative comparative outline of the discussed protocols is provided, based on multimedia traffic requirements.

Patent
06 Jul 1999
TL;DR: In this article, a method and apparatus for internet-worked communication between first and second wireless networks containing first-and second-pluralities of wireless nodes, respectively, is presented.
Abstract: A method and apparatus for internetworked communication between first and second wireless networks containing first and second pluralities of wireless nodes, respectively, is disclosed herein. In a preferred implementation an internetworking node participates in both the first and second wireless networks, and receives a first set of network information identifying each of the first plurality of wireless nodes and the services offered thereby. The internetworking node is configured to transmit the first set of network information to a master node of the second wireless network. The internetworking node also receives, from the second wireless network, a second set of network information identifying each of the second plurality of wireless nodes and the services offered thereby. In addition, the internetworking node may also transmit the second set of network information to a master node of the first wireless network. The first master node may be configured to broadcast information relating to the services offered by each of the first plurality of wireless nodes and the second wireless network. Likewise, the second master node may be configured to broadcast information relating to the services offered by each of the second plurality of wireless nodes and the second wireless network. In a preferred embodiment each of the first plurality of wireless nodes transmits an advertisement to the first master node specifying its address and services offered thereby. Similarly, each of the second plurality of wireless nodes transmits an advertisement to the second master node specifying its address and services offered thereby.

Patent
02 Aug 1999
TL;DR: In this paper, a wireless device, system and method for receiving and playing multimedia files streamed from a multimedia server over a wireless telecommunications network is described, where a desired multimedia file is selected from one or more multimedia files stored in the multimedia server, which server is operatively connected to the wireless network.
Abstract: A wireless device, system and method for receiving and playing multimedia files streamed from a multimedia server over a wireless telecommunications network. A desired multimedia file is selected from one or more multimedia files stored in the multimedia server, which server is operatively connected to the wireless telecommunications network. Successive blocks of data from the desired multimedia file are streamed over the wireless telecommunications network in a digitized and compressed format and received by the wireless telecommunications device. The received blocks of data from the streamed multimedia file are temporarily stored in a buffer in the wireless device, decoded and decompressed, and successively played through an audio and/or video output in the wireless device. The wireless device monitors the blocks of data stored in the buffer and signals the wireless telecommunications network to increase the rate that the data blocks are transmitted over the wireless network in the event that the data stored in the buffer falls below a minimum threshold level.

Patent
05 Nov 1999
TL;DR: In this article, the location of a user's wireless communication device relative to a number of network zones in the wireless communication network is used to assign a record to each of the operating zones.
Abstract: A method for dynamic location-based zone assignment for a wireless communication network is provided. The method utilizes the location of a user's wireless communication device relative to a number of network zones in the wireless communication network. The network zones and their respective coverage areas change from time-to-time. The method comprises receiving the location of the user's wireless communication device and accessing a geographical area definition of the user, wherein the geographical area definition includes at least one operating zone. The geographical area definition is translated to a current network area definition. The location of the user's wireless communication device is compared to the current network area definition in order to locate the user's wireless communication device relative to the operating zones. A record is then assigned based on which operating zone the user's wireless communication device is located.

Patent
09 Jul 1999
TL;DR: In this article, a packet-centric wireless point-to-multi-point (P2M) telecommunications system is proposed, which includes a wireless base station coupled to a first data network, one or more host workstations coupled to the first datacenter, and one or multiple CPE stations in wireless communication with the wireless BS over a shared bandwidth using a packetcentric protocol.
Abstract: A packet-centric wireless point to multi-point telecommunications system includes: a wireless base station coupled to a first data network; one or more host workstations coupled to the first data network; one or more subscriber customer premise equipment (CPE) stations in wireless communication with the wireless base station over a shared bandwidth using a packet-centric protocol; and one or more subscriber workstations coupled to each of the subscriber CPE stations over a second network; a resource allocation device optimizing end-user quality of service (QoS) and allocating shared bandwidth among the subscriber CPE stations; device for analyzing and scheduling an internet protocol (IP) flow over the shared wireless bandwidth, wherein the analyzing device comprises: identifying device identifying the IP flow.

Patent
29 Apr 1999
TL;DR: In this article, the authors proposed a network gateway that provides access to a network of computers to various wireless network carriers having different wireless network characteristics by using airlinks (or network drivers) to support the communications between the network gateway and the various wireless networks.
Abstract: The invention relates to centralized network access for wireless network carriers providing network access to wireless communication devices. The invention provides a network gateway (or proxy server) that provides access to a network of computers to various wireless network carriers having different wireless network characteristics. In one embodiment, the invention uses airlinks (or network drivers) to support the communications between the network gateway and the various wireless network carriers.

Patent
30 Nov 1999
TL;DR: In this paper, the number of packet routing addresses utilized within a wired subnet offering wireless services via subnet base stations is reduced by assigning a packet routing address to a wireless device accessing a wireless subnet upon power up of the wireless device.
Abstract: The number of packet routing addresses utilized within a wired subnet offering wireless services via subnet base stations is reduced by assigning a packet routing address to a wireless device accessing a wired subnet upon power up of the wireless device. A Dynamic Host Configuration Protocol (DHCP) server is utilized to assign the packet routing addresses, and supplies addresses either directly or indirectly via a node acting as a DHCP relay for a DHCP server. If the assigned packet routing address is a care-of address for a foreign domain, the address is released upon wireless device power down or upon handoff of the wireless device to a new domain. If the assigned packet routing address is an address for the wireless device within a home domain, the address is released upon wireless device power down.

Patent
Paul H. Boudreaux1
16 Dec 1999
TL;DR: In this paper, a method of controlling handover of real-time packet data flow within a wireless telecommunications system packet domain without disrupting communication between user equipment and the anchor packet gateway is presented.
Abstract: A method of controlling handover of real-time packet data flow within a wireless telecommunications system packet domain without disrupting communication between user equipment and the anchor packet gateway. In a preferred embodiment, the wireless telecommunications system includes user equipment such as a wireless telephone, a serving wireless gateway, a drift wireless gateway, and an anchor packet gateway. Once it is determined that handover of real-time packet data flow is needed, the drift wireless gateway is prepared to become the serving wireless gateway. The anchor packet gateway is then prepared for serving wireless gateway relocation by having the anchor packet gateway initiate bicasting of downlink packet data flow. Uplink and downlink packet data flows are then monitored at the drift wireless gateway and the drift wireless gateway and the serving wireless gateway are synchronized for relocation. The drift wireless gateway is then utilized as the new serving wireless gateway.

Patent
27 Aug 1999
TL;DR: In this paper, a wireless location-based information-retrieval system includes a transceiver for sending and receiving communications across a wireless communication network, a position-determination device for determining the location of the wireless device, and an Internet browser.
Abstract: A wireless location-based information-retrieval system includes a wireless communication device. The wireless device has a transceiver for sending and receiving communications across a wireless communication network, a position-determination device for determining the location of the wireless device, and an Internet browser. A remote server communicates with the wireless device. The server receives the location data from the wireless device over the network and maintains a web page listing information service options. The information service options are accessible to and selectable by the wireless device via the browser. The server retrieves information from a database based on the location data provided by the wireless device and on the selected service option. The retrieved information is sent to the wireless device over the network.

Patent
16 Sep 1999
TL;DR: In this paper, a wireless server system and method for communicating between a user terminal and Internet a wirelessly is proposed, which is based on the user terminal having a fixed terminal and a terminal unit so that an Internet connection can be made by way of the terminal unit to an appropriate wireless server.
Abstract: A wireless server system and method for communicating between a user terminal and Internet a wirelessly. It is based on a user terminal having a fixed terminal and a terminal unit so that an Internet connection can be made by way of the terminal unit to an appropriate wireless server. The system has at least one wireless server connected to Internet; and a plurality of wireless station devices connected to the wireless server, and the system communicates wirelessly with the terminal unit of the user terminal; wherein one wireless server within a district of communication range of the wireless station devices is designated as a home server for the terminal unit, and the fixed terminal receives data sent wirelessly from Internet by way of the terminal unit.

Patent
13 Dec 1999
TL;DR: In this article, an apparatus and method for disabling wireless communication devices is presented, where one or more capabilities of the wireless communications devices are disabled inside the disabling zone, and the devices are either geographically fixed or moveable.
Abstract: An apparatus and method for disabling wireless communication devices establishes a disabling zone. Inside the disabling zone, one or more capabilities of the wireless communication devices are disabled. The wireless communication devices may include cellular phones, beepers, pagers, portable computers, electronic personal attendants, and/or similar wireless devices. In a first embodiment, the zone is formed in conjunction with a power monitoring unit proximate the zone. In a second embodiment, the zone is formed in conjunction with a position monitoring system determining the geographical position of the wireless communication devices. In both the first and second embodiments, the zone may be either geographically fixed or moveable.

Proceedings ArticleDOI
01 Aug 1999
TL;DR: Scheduling results from the wireline domain do not carry over to wireless systems because wireless channels have unique characteristics not found in wireline channels, namely, limited bandwidth, bursty channel errors and location-dependent channel errors.
Abstract: Recently, there has been widespread interest in the extension of data networks to the wireless domain. However, scheduling results from the wireline domain do not carry over to wireless systems because wireless channels have unique characteristics not found in wireline channels, namely, limited bandwidth, bursty channel errors and location-dependent channel errors.

Journal ArticleDOI
TL;DR: A dynamic channel reservation scheme to improve the utilization of wireless network resources while guaranteeing the required QoS of handoff calls and keep the new call blocking probability as low as possible.
Abstract: We present a dynamic channel reservation scheme to improve the utilization of wireless network resources while guaranteeing the required QoS of handoff calls. The wireless channels are dynamically reserved by using the request probability determined by the mobility characteristics and channel occupancy to guarantee acceptable quality of handoff calls and keep the new call blocking probability as low as possible.

Patent
25 Jun 1999
TL;DR: In this article, the authors describe a communication system that allows for the transmission of voice and data over a wireless network, such as a GSM telephone and a pen input device capable of collecting information about an image written on a writing surface.
Abstract: The systems and methods described herein provide communication systems that allow for the transmission of voice and data over a wireless network. To that end, the systems described herein include a mobile wireless communication system, such as a GSM telephone, and a pen input device capable of collecting information about an image written on a writing surface and capable of transmitting that information into the wireless communication device.

Journal ArticleDOI
TL;DR: The technological challenges and potential solutions in designing these myriad future "wireless terminals" that will handle diverse data types, have limited battery resources, and operate in environments that are unplanned, insecure, and time-varying, and have context-dependent services are described.
Abstract: The current wireless networks are being replaced by emerging wireless networking technologies that are intrinsically designed to support packet data and multimedia services. This will lead to novel networked applications and services, which in turn will require wireless terminals capable of exploiting these services. What shape will these next-generation wireless terminals take? The answer, based on the much talked about notion of "convergence", would appear to be a marriage of the laptop or PC with a wireless phone in the same package. We argue that such a complex one-size-fits-all voice-data integrated wireless terminal will, at best, be a point solution. Rather, with the availability of cheap radio and computing hardware and ubiquitous low-cost indoor and outdoor wireless networking infrastructures, the capability to access a wireless network will soon be embedded into a variety of devices, gadgets, and appliances with specialized functions in our environment. In this article we describe the technological challenges and identify potential solutions in designing these myriad future "wireless terminals" that will handle diverse data types, have limited battery resources, and operate in environments that are unplanned, insecure, and time-varying, and have context-dependent services.

Patent
Hind John Raithel1, Marcia L. Peters1
21 May 1999
TL;DR: In this paper, a method and system for enabling wireless devices distributed throughout an enterprise to be efficiently initialized for secure communications is presented, which utilizes well known public key cryptography and machine unique identifiers to establish a secure channel and initialize the wireless devices.
Abstract: A method and system for enabling wireless devices distributed throughout an enterprise to be efficiently initialized for secure communications. The method and system utilize well known public key cryptography and machine unique identifiers to establish a secure channel and initialize the wireless devices.

Patent
Markku Korpi1, Stefan Karapetkov1
20 Sep 1999
TL;DR: In this article, the authors propose an arrangement and a method with which wireless terminal devices which can usually be reached via a call number of one individual network computer can also be reached when they are located in the wireless communication area of a base station that is connected to another network computer.
Abstract: An arrangement and a method with which wireless terminal devices which can usually be reached via a call number of one individual network computer can also be reached when they are located in the wireless communication area of a base station that is connected to another network computer. To this end, connection information is retrieved via a mobility server, and a connection setup to a corresponding network computer in whose radio area the wireless terminal device is located is controlled via that mobility server. The wireless terminal device delivers information, which is transmitted to the mobility server and from which, together with additional information from the network computer or the base station, this server is able to derive the information for the connection setup to the wireless terminal device. In order to limit the utilized network computers to only a switching function, performance features of the wireless terminal device are realized via a performance feature server, which controls the corresponding network computer via a CTI interface. The mobility servers are likewise connected to the respective network computers via a CTI interface. In this way, it is possible to realize private wireless communication networks with DECT functionality and with a large coverage, in which networks it is possible to reach wireless terminal devices at will, though they are dialed simply via the call number of a single network computer allocated to them.