Patents Assigned to Nortel Networks, Ltd.
  • Patent number: 6553226
    Abstract: A method of managing inter-satellite links (ISLs) in a LEOS system. Intra-plane ISLs are established between a subject satellite and adjacent satellites in the same orbital plane. These intra-plane ISLs are generally fixed during all operations and will not be severed or reestablished once they have been initially established. Neighbor ISLs are established to minimize offset between a subject satellite and the neighboring satellites with which it has neighbor ISLs. However, satellites in the neighbor plane may be selected for neighbor ISLs which do no currently provide the minimal offset position but soon will based upon the continuing relative motion between the planes. Altering neighbor ISLs for an orbital plane is coordinated within a plane to eliminate loops and inefficient routing paths. Seam ISLs are also managed. When a satellite operates in a teardrop area (area in which the satellite provides some coverage), the satellite establishes seam ISLs to up to two seam satellites in a seam orbital plane.
    Type: Grant
    Filed: August 27, 1999
    Date of Patent: April 22, 2003
    Assignee: Nortel Networks LTD
    Inventor: Jeffrey Lee Watson
  • Patent number: 6553227
    Abstract: A wireless communication system constructed according to the present invention assigns each serviced mobile unit to a serving mobile switching center to minimize mobility management overhead and to equalize loading among a plurality of mobile switching centers. The wireless communication system includes the plurality of mobile switching centers and a base station system which includes a plurality of base station controllers, each of which couples to a plurality of base stations. A plurality of mobile units served by the system are assigned to the mobile switching centers so that loading is equalized. In one particular construction of the wireless communication system, a dispatching switch couples the base station system to the plurality of mobile switching centers and performs the assignments of the mobile units. In an example of operation, upon attachment of a mobile unit, the dispatching switch determines loading of each of the mobile switching centers.
    Type: Grant
    Filed: July 17, 2000
    Date of Patent: April 22, 2003
    Assignee: Nortel Networks LTD
    Inventors: Joseph S. M. Ho, Nhut Nguyen, Hakan Ernam
  • Patent number: 6549771
    Abstract: An improved method for programming a mobile telephone over the air within a mobile telephone communication network is disclosed. The mobile telephone communication network includes an over-the-air function, a customer service center, a mobile switching center, a base station controller, and multiple base transceiver stations. The over-the-air function, using the mobile switching center, the base station controller, and one of the base transceiver stations for transport, initially sends a request over the air to a mobile telephone within the mobile telephone communication network to interrogate the mobile telephone's protocol capability. In response to the request, the mobile telephone sends a protocol capability response message over the air back to the over-the-air function. The protocol capability response message includes a BAND_MODE_CAP field that describes the band and mode capability information of the mobile telephone.
    Type: Grant
    Filed: April 17, 2001
    Date of Patent: April 15, 2003
    Assignee: Nortel Networks Ltd.
    Inventors: Kim Chang, Chenhong Huang, Robert E. Denman
  • Patent number: 6529491
    Abstract: The private/residential wireless communication system uses the code division multiple access air interface to provide communication with radiotelephones. The present invention provides support for both physical and virtual private systems. A radiotelephone monitors the broadcast channel of the public system to obtain private system information. The radiotelephone use the broadcast information together with pre-programmed stored private system information in the radiotelephone memory to acquire and register with the private systems. If the radiotelephone locates a private system that is not stored in its memory, it obtains relevant information for registering with that system. The radiotelephone then stores the information of accepting systems. This information is displayed so that a system can be chosen. The radiotelephone then registers with the chosen system.
    Type: Grant
    Filed: November 5, 1998
    Date of Patent: March 4, 2003
    Assignee: Nortel Networks Ltd.
    Inventors: Kim Chang, Ibrahim Ghaleb, Huang Chenhong
  • Patent number: 6529741
    Abstract: The invention provides a system and method for controlling transmission power of a mobile unit in a wireless communication system which minimizes transmission power overshoot caused by counteracting the effects of deep fading. Sets of power control bits are transmitted from the base station to the mobile unit using &pgr;/4 DQPSK modulation. A first set of the bits indicates to the mobile unit a request to increase the mobile units transmission power by a predetermined amount. A second set of the bits indicates to the mobile unit that the mobile unit should increase its transmission power by an amount which is greater than the predetermined amount. A third set of the bits indicates to the mobile unit a request to decrease the mobile units transmission power by the predetermined amount. A fourth set of the bits indicates to the mobile unit that the mobile unit should decrease its transmission power by the amount which is greater than the predetermined amount.
    Type: Grant
    Filed: April 16, 1999
    Date of Patent: March 4, 2003
    Assignee: Nortel Networks Ltd.
    Inventors: Wen Tong, Evelyn Le Strat
  • Patent number: 6519249
    Abstract: An Internet Protocol (IP) telephony system manages Gatekeeper subscriber load by assigning subscriber load among a plurality of Gatekeepers during the Gatekeeper discovery and registration process. A Registration Load Management Unit (RLMU) is primarily responsible for assigning subscriber load to the plurality of Gatekeepers. In one embodiment, the plurality of Gatekeepers are organized without a hierarchy structure and are made up of a plurality of Gatekeeper service nodes and a plurality of Gatekeeper Database nodes. The Gatekeeper service nodes provide the Registration, Admission, Status, Location, Call Set Up and other operating functions of the Gatekeeper while the plurality of Gatekeeper Database nodes store subscriber information. In a second embodiment, the plurality of Gatekeepers are organized in a hierarchy with a Root Gatekeeper at the top of the hierarchy and a plurality of Gatekeepers residing below the Root Gatekeeper in the hierarchy.
    Type: Grant
    Filed: December 23, 1998
    Date of Patent: February 11, 2003
    Assignee: Nortel Networks LTD
    Inventors: Brian Joseph Bennefeld, Patrick SzeChing Ma, Gregory Scott Graham, Michael Flynn Thomas
  • Patent number: 6519233
    Abstract: A CDMA communication system supports designated mode data bursts on a reverse link contention based channel from a subscriber unit to a base station. The reverse link contention based channel also supports contention-based transmissions from the subscriber unit to the base station. When transmissions are scheduled and serviced in the designated mode data burst, collisions are avoided. Further, because setting up the designated mode data bursts on the reverse link contention based channel require little overhead as compared to the setup of a traffic channel the CDMA system is operated at a greater efficiency. The reverse link contention based channel may be a Reverse Common Control Channel, a Reverse Access Channel or another contention-based channel. Designated mode data bursts on the reverse link contention based channel may consume a single slot or multiple slots.
    Type: Grant
    Filed: June 11, 1999
    Date of Patent: February 11, 2003
    Assignee: Nortel Networks, Ltd.
    Inventor: Alberto Gutierrez
  • Patent number: 6498790
    Abstract: A time division multiple access cellular communication system supports a packet channel is alterable between a packet control channel configuration and a packet traffic channel configuration. In the packet control channel configuration, the packet channel may provide only control functions or a combination of control and traffic functions. The packet channel may also be configured in a packet traffic configuration so that the packet channel provides only packet traffic functions. In this configuration, another packet channel must be configured in the packet control channel configuration to provide control functions for the packet traffic only packet channel. A Digital Control Channel (DCCH) includes information relating to a Beacon Packet Control Channel (PCCH), which contains information on the allocated packet channels. The subscriber unit initiates its packet data operations within the system.
    Type: Grant
    Filed: September 21, 1998
    Date of Patent: December 24, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Kamel M. Shaheen, Akbar Rahman, Chenhong Huang
  • Patent number: 6493351
    Abstract: A controller module is coupled to a plurality of application modules over a backplane. The backplane comprises a differential bus(s) having a TX and RX data signal, a differential clock signal, and a single ended collision detection line. The application modules transmit data to the controller module. The controller module retransmits a recovered version of the data back to the application modules over the collision detection line. Each application module compares the retransmitted data bits with the data bits it originally transmitted. If the data is not the same, a collision has occurred and the application module removes itself from the bus. If the data is the same as that transmitted originally, that particular application module continues to transmit on the bus. Metastability at the controller module's differential receiver enables multiple differential transmitters to be on the differential bus at the same time.
    Type: Grant
    Filed: April 21, 1999
    Date of Patent: December 10, 2002
    Assignee: Nortel Networks Ltd.
    Inventor: Ronald K. Shideler
  • Patent number: 6487083
    Abstract: A technique for improving electrical signal performance in multilayer circuit boards by eliminating the need for electrically conductive vias is disclosed. In one embodiment, the technique is realized as an improved multilayer circuit board having an electrically conductive signal layer disposed beneath at least one dielectric layer. The improvement comprises a cavity in the multilayer circuit board extending through the at least one dielectric layer so as to expose at least a portion of the electrically conductive signal layer within the cavity. The cavity is sized to accommodate an electronic component therein such that the electronic component makes electrical contact with the exposed portion of the electrically conductive signal layer, thereby eliminating the need for an electrically conductive via electrically connected to the electrically conductive signal layer and formed through the at least one dielectric layer or any other layer of the multilayer circuit board.
    Type: Grant
    Filed: August 10, 2000
    Date of Patent: November 26, 2002
    Assignee: Nortel Networks Ltd.
    Inventor: Herman Kwong
  • Publication number: 20020122402
    Abstract: A method, device and base station for using a code division multiple access carrier for wireless reverse link communication between the device and the base station. An operational profile of the device is determined in which the operational profile includes a degree of unit mobility. A first carrier for wireless code division multiple access communication from the device to the base station is selected based on the determined operational profile of the device. A wireless communication link between the device and the base station is established using the first carrier. According to one aspect, the first carrier is one of an asynchronous code division multiple access signal and a synchronous code division multiple access signal.
    Type: Application
    Filed: March 1, 2001
    Publication date: September 5, 2002
    Applicant: Nortel Networks Ltd.
    Inventors: Shalini S. Periyalwar, Bassam M. Hashem, Leo L. Strawczynski
  • Patent number: 6438369
    Abstract: The present invention relates to a cellular and PCS enhanced roaming arrangement for assuring that a roaming mobile station is serviced outside its home service market be a preferred service provider. A mobile station outside its home market, when attempting to register or initiate a call, will attempt to connect to a remote service provider in the geographic region where it is located in the same manner as it would in the home market. The remote service provider will contact the home service provider seeking, among other things, service information and account status. In the event that the home service provider has more favorable arrangements with another service provider in the geographic region where the mobile station is located, the home service provider will transmit redirection instructions to the remote service provider which is transmitted to the mobile station.
    Type: Grant
    Filed: December 14, 1999
    Date of Patent: August 20, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Chenhong Huang, Kim T. Chang, Girish Patel
  • Patent number: 6430174
    Abstract: A communication system includes a voice subsystem and a multimedia subsystem. The voice subsystem couples to the PSTN and services a voice communication received by the communication system from a caller. The multimedia subsystem couples to the voice subsystem, supports multimedia communications and provides a multimedia interface to the caller upon receipt of the voice communication from the caller. When the call originates from a phone that supports multimedia communications, the multimedia subsystem directs the multimedia interface to the phone but, when the call originates from a phone that does not supports multimedia communications, the multimedia interface is directed to an associated multimedia enabled device. The voice subsystem provides call processing and routing functions as well as messaging functions and extended services. The multimedia subsystem includes an information posting subsystem and an information access subsystem that allow callers to post information and to access information.
    Type: Grant
    Filed: December 26, 1997
    Date of Patent: August 6, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Darrell L. Jennings, Frederick W. Hansen
  • Patent number: 6373857
    Abstract: An Internet Protocol (IP) telephony system cross-references transport addresses of Gatekeepers using a domain name of the IP telephony system. The IP telephony system is serviced by at least one Gatekeeper and the transport address for each Gatekeeper is stored on a Domain Name Server (DNS). An A record or other suitable record may be employed within the DNS to index the transport addresses of the Gatekeepers to the IP telephony system domain name. A calling endpoint first queries the DNS for the transport address of a Gatekeeper servicing the IP telephony system. The DNS address retrieves at least one transport address for the Gatekeeper(s) and returns the transport address(es) to the calling endpoint. When querying the DNS, the calling endpoint may use an identifier such as subscribername@Gatekeeper.ABC.domain where the user name of the called endpoint is “subscribername” and the domain name of the IP telephony system is ABC.domain.
    Type: Grant
    Filed: November 13, 1998
    Date of Patent: April 16, 2002
    Assignee: Nortel Networks Ltd.
    Inventor: Patrick SzeChing Ma
  • Patent number: 6374109
    Abstract: A wireless communication system facilitates wireless communication with a subscribing unit operating within a respective service area. At least one base station supports wireless communication within the service area in a plurality of frequency bands and according to a plurality of communication protocols. In a broadcast message, a transmitting base station indicates to the subscribing unit the plurality of frequency bands and the plurality of communication protocols available. The subscribing unit receives the broadcast message and communicates with the base station on one of the plurality of frequency bands according to one of the plurality of communication protocols. In another embodiment, the system includes a plurality of base stations providing overlying coverage within the service area. In such systems, multiple broadcast message may provide information regarding the overlying coverage provided.
    Type: Grant
    Filed: July 31, 2000
    Date of Patent: April 16, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Kamel M. Shaheen, Chenhong Huang
  • Patent number: 6373831
    Abstract: Methods and apparatus for transmitting data over a multi-channel CDMA system are disclosed in accordance with the teachings of the present invention wherein the system includes an encoder for encoding a data stream with error correction, an interleaver for interleaving the data stream, a multiplexor for multiplexing a plurality of power control symbols onto the data stream, and an inverse-multiplexor for inverse-multiplexing the data stream onto multiple different communication channels. The system may also include additional error correction encoding and interleaving steps.
    Type: Grant
    Filed: March 25, 1998
    Date of Patent: April 16, 2002
    Assignee: Nortel Networks Ltd.
    Inventors: Norman P. Secord, Mo-Han Fong, Geng Wu, Leo Strawczynski, Ahmad Jalali, Robert Matyas, Ning Guo, Wookwon Lee, Amir Bigloo
  • Patent number: 6366780
    Abstract: A method for managing subscriber load within a terrestrial cellular wireless communication system includes organizing a plurality of cells that form a service area into a plurality of corridors and managing accessibility within each corridor. Each of the plurality of corridors includes a plurality of cells/sectors that have similar loading patterns and that form a contiguous portion of the service coverage area. Periodically, corridor load is determined for each corridor. Further, access rules for the plurality of base stations forming the corridor are determined, these access rules determining which subscribers may access the plurality of base stations forming the corridor. When a loading level for any of the base stations within the corridor-compares unfavorably to a respective loading threshold, access rules for all of the plurality of base stations forming the particular corridor are altered.
    Type: Grant
    Filed: October 8, 1998
    Date of Patent: April 2, 2002
    Assignee: Nortel Networks Ltd.
    Inventor: Prem A. Obhan
  • Patent number: 6363251
    Abstract: The present invention relates to a cellular and PCS enhanced roaming arrangement for assuring that a roaming mobile station is serviced outside its home service market be a preferred service provider. A mobile station outside its home market, when attempting to register or initiate a call, will attempt to connect to a remote service provider in the geographic region where it is located in the same manner as it would in the home market. The remote service provider will contact the home service provider seeking, among other things, service information and account status. In the event that the home service provider has more favorable arrangements with another service provider in the geographic region where the mobile station is located, the home service provider will transmit redirection instructions to the remote service provider which is transmitted to the mobile station.
    Type: Grant
    Filed: March 29, 2000
    Date of Patent: March 26, 2002
    Assignee: Nortel Networks LTD
    Inventors: Chenhong Huang, Kim T. Chang, Girish Patel
  • Patent number: 6359979
    Abstract: A telephone network includes an Enhanced Call Routing (ECR) function that reroutes calls when the high usage route and fixed tandem routes are overloaded or otherwise unavailable. The ECR function tracks the operation of the telephone network on the basis of origination switches and destination switches and provides temporary network rerouting during outages and unusual loading situations. Further, the ECR function supports Local Number Portability (LNP) so that it may operate in those telephone networks that are designed and/or modified to support LNP. The ECR function resides on a signaling network element such as a Service Switching Point (SSP) and/or a Service Control Point (SCP). A call setup request is received by a Service Switching Point (SSP), an origination switch in the traffic network, and intended for a destination switch. Initial routing via a high usage route and fixed tandem route(s) are unsuccessful. The SSP sends a Network_Busy message to the STP/SCP supporting the ECR function.
    Type: Grant
    Filed: December 31, 1998
    Date of Patent: March 19, 2002
    Assignee: Nortel Networks LTD
    Inventors: Weilin Wang, Joyce Bradley
  • Patent number: 6236716
    Abstract: A call parking and paging system includes a call parking entity and a paging entity. The call parking entity receives a call and automatically parks the call, in some operations against a designated resource. The paging entity provides a page based upon an intended recipient of the call. Upon receiving a response to the page, the call parking and paging system may then assist in delivering the parked call. The call parking and paging system may be supported by a PBX, by a telephone system central exchange or by another communication system. Additional features may include a voice processing system, a validation entity, a directory system, a messaging system and an information database. Paging resources support voice pages, electronic pages and email that apprise the intended recipient of the parked call.
    Type: Grant
    Filed: February 11, 1998
    Date of Patent: May 22, 2001
    Assignee: Nortel Networks LTD
    Inventors: Nicholas R. D. Marcus, Randy M. Hoekstra, Joel J. Joseph, Jr., Richard A. Weiss, Susan M. King