Patents Assigned to Nortel Networks Limited
  • Patent number: 8086235
    Abstract: This invention provides a method, system and apparatus for controlling mobility on a wireless network, which includes retrieving a network mobility preference, the network mobility preference indicating a level of mobility service for the mobile station, the level of mobility service indicating the extent to which the mobile station can handoff among base stations of the wireless network, and establishing a level of mobility service for the mobile station based on the retrieved network mobility preference. The method and apparatus may further include determining the level of mobility service for the mobile station to be fully or partially restricted based on the mobility preference.
    Type: Grant
    Filed: December 6, 2006
    Date of Patent: December 27, 2011
    Assignee: Nortel Networks Limited
    Inventors: Yusupha Touray, Fayaz Kadri
  • Patent number: 8085670
    Abstract: A system for originating connectivity fault management (CFM) frames on non-CFM aware switches is disclosed. In the disclosed system, an OAM (Operations Administration and Management) proxy networking device connected to a core Ethernet network operates with one or more CPE (Customer Premises Equipment) devices to which it is communicably connected to support CFM out to the CPE devices without requiring that the CPE devices themselves implement CFM functionality. The OAM proxy networking device generates Connectivity Check (CC) frames, Loopback reply frames, and Linktrace reply frames for MEPs (Maintenance End Points) or MIPs (Maintenance Intermediate Points) contained in communication ports on the CPEs. These CFM frames generated by the OAM proxy networking device are then sent within messages from the OAM proxy networking device to the appropriate CPE.
    Type: Grant
    Filed: December 21, 2005
    Date of Patent: December 27, 2011
    Assignee: Nortel Networks Limited
    Inventors: John Osswald, Michael Poon
  • Patent number: 8085814
    Abstract: A method and apparatus are provided for performing acquisition, synchronization and cell selection within an MIMO-OFDM communication system. A coarse synchronization is performed to determine a searching window. A fine synchronization is then performed by measuring correlations between subsets of signal samples, whose first signal sample lies within the searching window, and known values. The correlations are performed in the frequency domain of the received signal. In a multiple-output OFDM system, each antenna of the OFDM transmitter has a unique known value. The known value is transmitted as pairs of consecutive pilot symbols, each pair of pilot symbols being transmitted at the same subset of sub-carrier frequencies within the OFDM frame.
    Type: Grant
    Filed: October 2, 2006
    Date of Patent: December 27, 2011
    Assignee: Nortel Networks Limited
    Inventors: Jianglei Ma, Ming Jia, Peiying Zhu, Wen Tong
  • Patent number: 8085676
    Abstract: A resilient virtual Ethernet ring has nodes interconnected by working and protection paths. If a span fails, the two nodes immediately on either side of the failure are cross-connected to fold the ring. Working-path traffic is cross-connected onto the protection path at the first of the two nodes and is then cross-connected back onto the working path at the second of the two nodes so that traffic always ingresses and egresses the ring from the working path. A traffic originating node, upon determining that transmitted packets are being looped back due to a fault on a primary path, is adapted to switch transmission of data packets from the primary path to a secondary path.
    Type: Grant
    Filed: December 13, 2007
    Date of Patent: December 27, 2011
    Assignee: Nortel Networks Limited
    Inventors: Darek Skalecki, Gerard L. Swinkels, David I. Allan, Nigel L. Bragg, Marc Holness
  • Publication number: 20110310776
    Abstract: The present invention relates generally to a cellular telecommunications network. Each cell has at least one base station for sending messages on a downlink of a Frequency Division Duplex (FDD) to end user equipments within the cell and for receiving messages on an uplink from end user equipments within the cell. Other end user equipment located within the cell which have no or only poor communication directly with the base station over the FDD communicate with the base station indirectly via an intermediate end user equipment, such as a mobile telephone. The intermediate end user equipment includes an FDD transceiver and a Time Division Duplex (TDD) transceiver and an FDD/TDD interface.
    Type: Application
    Filed: June 30, 2011
    Publication date: December 22, 2011
    Applicant: Nortel Networks Limited
    Inventor: Keith Russell EDWARDS
  • Patent number: 8082441
    Abstract: In a hitless manual cryptographic key refresh scheme, a state machine is independently maintained at each network node. The state machine includes a first state, a second state, and a third state. In the first state, which is the steady state, a current cryptographic key is used both for generating signatures for outgoing packets and for authenticating signatures of incoming packets. In the second state, which is entered when a new cryptographic key is provisioned, the old (i.e. formerly current) key is still used for generating signatures for outgoing packets, however one or, if necessary, both of the old key and the newly provisioned key is used for authenticating signatures of incoming packets. In the third state, the new key is used for generating signatures for outgoing packets and either one or both of the old key and new key are used for authenticating signatures of incoming packets.
    Type: Grant
    Filed: June 10, 2009
    Date of Patent: December 20, 2011
    Assignee: Nortel Networks Limited
    Inventors: Richard Gauvreau, Michael Aalders, Kim Edwards
  • Publication number: 20110307755
    Abstract: A method for constructing a low-density parity-check (LDPC) code using a structured base parity check matrix with permutation matrix, pseudo-permutation matrix, or zero matrix as constituent sub-matrices; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for constructing a LDPC code using a structured base parity check matrix H=[Hd|Hp], Hd is the data portion, and Hp is the parity portion of the parity check matrix; the parity portion of the structured base parity check matrix is such so that when expanded, an inverse of the parity portion of the expanded parity check matrix is sparse; and expanding the structured base parity check matrix into an expanded parity check matrix. A method for encoding variable sized data by using the expanded LDPC code; and applying shortening, puncturing.
    Type: Application
    Filed: June 9, 2011
    Publication date: December 15, 2011
    Applicants: NORTEL NETWORKS INC., NORTEL NETWORKS LIMITED
    Inventors: Michael LIVSHITZ, Aleksandar PURKOVIC, Nina BURNS, Sergey SUKHOBOK, Muhammad CHAUDHRY
  • Publication number: 20110306291
    Abstract: Methods and apparatus are described for enabling downlink transparent relay in a wireless communication network. In a wireless communications network, a base station and a mobile station may communicate with each other via a relay station, as needed. Transparent relay may allow for relay communication between a base station and a mobile station although the mobile station is unaware of the relay station. However, non-contiguous transmission of a relay station may lead to channel quality measurement and channel estimation degradation during downlink transparent relay. According to some aspects, a base station may schedule a mobile station to a transmission mode that utilizes dedicated pilot signals for downlink transparent relay, and a relay station may transmit data and dedicated pilot signals over the same channel resources as the base station. According to some aspects, the relay station may null common pilot signals transmitted by the base station.
    Type: Application
    Filed: August 12, 2009
    Publication date: December 15, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: Jianglei Ma, Hua Xu, Hang Zhang, Peiying Zhu, Wen Tong
  • Patent number: 8077599
    Abstract: An adaptable orthogonal frequency-division multiplexing system (OFDM) that uses a multiple input multiple output (MIMO) to having OFDM signals transmitted either in accordance with time diversity to reducing signal fading or in accordance with spatial diversity to increase the data rate. Sub-carriers are classified for spatial diversity transmission or for time diversity transmission based on the result of a comparison between threshold values and at least one of three criteria. The criteria includes a calculation of a smallest eigen value of a frequency channel response matrix and a smallest element of a diagonal of the matrix and a ratio of the largest and smallest eigen values of the matrix.
    Type: Grant
    Filed: August 13, 2010
    Date of Patent: December 13, 2011
    Assignee: Nortel Networks Limited
    Inventors: Shiquan Wu, Wen Tong, Leo Strawczynski
  • Patent number: 8078708
    Abstract: A Grid Proxy Architecture for Network Resources (GPAN) is proposed to allow Grid applications to access resources shared in communication network domains. GPAN bridges Grid services serving user applications and network services controlling network devices through its proxy functions such as resource data and management proxies. Working with Grid resource index and broker services, GPAN employs distributed network service peers (NSP) in network domains to discover, negotiate and allocate network resources such as bandwidth for Grid applications. An elected master NSP is the unique Grid node that runs GPAN and represents the whole network to share network resources to Grids without Grid involvement of network devices. GPAN provides the Grid Proxy service (GPS) to interface with Grid services and applications, and the Grid Delegation service (GDS) to interface with network services to utilize network resources. Resource-based XML messaging is employed for the GPAN proxy communication.
    Type: Grant
    Filed: December 21, 2004
    Date of Patent: December 13, 2011
    Assignee: Nortel Networks Limited
    Inventors: Phil Wang, Indermohan Monga, Tal Lavian, Ramesh Durairaj, Franco Travostino
  • Patent number: 8077636
    Abstract: Transcoders and mixers having reduced algorithmic delay and processing complexity. An improved mixer for signals having encoded speech parameters wherein the parameters obtained through decoding are used by a parameter estimator to improve the encoding by providing a parameter estimate for the mixed signal. In the case of pitch parameters, the mixer uses the principle of strong-pitch-domination. The mixing of wideband signals is simplified by performing mixing of individual lower and upper sub-bands. A transcoder and a mixer that converts a wideband signal into a narrowband signal relies upon high frequency suppression. A transcoder and a mixer that converts a narrowband signal into a wideband signal relies upon filter combination.
    Type: Grant
    Filed: October 9, 2009
    Date of Patent: December 13, 2011
    Assignee: Nortel Networks Limited
    Inventors: Mohamed Samy El-Hennaway, Rafik A. Goubran, Zhihong Qian
  • Publication number: 20110298565
    Abstract: Some embodiments of the invention provide a filter having at least one first filter, each first filter being a band-reject type filter having a first set of filter parameters that are a function of a first material used to fabricate the at least one first filter, and at least one second filter, each second filter having a second set of filter parameters that are a function of a second material used to fabricate the at least one second filter, each second filter being one of a band-reject type filter and a band pass type filter. The at least one first filter and the at least one second filter are then cascaded together to form the filter. The first material and the second material are different materials. The cascaded filter has a new third set of filter parameters that are a function of both the first material and the second material. Other embodiments of the invention include a method for fabricating the filter and a method of filtering using such a cascaded filter.
    Type: Application
    Filed: August 15, 2011
    Publication date: December 8, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventor: Chun-Yun Jian
  • Publication number: 20110299439
    Abstract: A mobile terminal in a wireless communication network may be one of several modes of operation. When in an idle mode, the mobile terminal may avoid a lengthy random access procedure normally associated with responding to a page from a base station, if the base station includes in the page an indication of a resource that the mobile terminal may utilize when responding to the page. Additionally, the mobile terminal may transmit an efficient location update MAC header to a base station, whether prompted to by a page from the base station or not. Furthermore, without leaving the idle mode or a sleep mode, the mobile terminal may exchange short data burst messages with a base station.
    Type: Application
    Filed: August 12, 2011
    Publication date: December 8, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: HANG ZHANG, MO-HAN FONG, PEIYING ZHU, WEN TONG
  • Publication number: 20110299405
    Abstract: Methods and devices for logically segmenting an LSP so that OAM DTUs may be used to determine the performance and/or the status of LSP segments. To segment a previously determined LSP, a dedicated subpath (a logical LSP) within that predetermined LSP is defined between two LSRs that are capable of processing OAM DTUs. The source node (source LSR) establishes a logical LSP between itself and the destination node (destination LSR) using an LDP. In doing this, the logical LSP traverses a specific path and transits through specific nodes in that path. The source node then transmits an OAM DTU or any other specialized DTU to the destination node using a label specifically associated with the logical LSP that was established. The characteristic of the specific path traversed by the logical LSP can thus be determined by when, how, and if the specialized DTU is received by the destination node.
    Type: Application
    Filed: August 18, 2011
    Publication date: December 8, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventor: Mina AZAD
  • Patent number: 8073398
    Abstract: A transceiver with an adaptable filter and a method of controlling the settings of the filter to adapt to local channel assignments and usage are provided. The adaptable filter is connected in at least one of the transmitter path and the receiver path of the transceiver to separate signals from adjacent spectrum blocks to permit use of all of the channels in the adjacent spectrum blocks and to separate signals in adjacent or nearby channels in a shared-channel block. A method and system for forward link control signaling are provided. The forward link control signaling includes a frame for transmission that includes at least one control channel that includes control information for receivers sharing a common characteristic, and a guide channel that includes information pertaining to the at least one control channel, including control information for receivers sharing a common characteristic.
    Type: Grant
    Filed: March 26, 2007
    Date of Patent: December 6, 2011
    Assignee: Nortel Networks Limited
    Inventor: David Steer
  • Patent number: 8073554
    Abstract: The present invention relates to a system and method for providing power management to sensing nodes in a sensor network. A system may include a plurality of sensing nodes, each sensing node connected through a power management device to an external power source, such as a powered node of another network, for managing power from the external power source to the sensing node. Beneficially, a plurality of power management devices allow for a sensor network of fixed or mobile wireless sensing nodes or sensor gateways to make use of power from an external source such as an another network e.g. an existing emergency lighting system or other similar powered building system. Thus for example, a sensor or group of sensing nodes and their associated power management devices may be integral with or co-located in proximity to powered nodes of these other networks.
    Type: Grant
    Filed: December 20, 2006
    Date of Patent: December 6, 2011
    Assignee: Nortel Networks Limited
    Inventors: Brian Vezza, Kent Felske, Alan Graves, John Watkins, Guy Duxbury, Tom Chmara, Jeff Fitchett
  • Patent number: 8073063
    Abstract: Aspects of the invention include methods and devices for inserting data and pilot symbols into Orthogonal Frequency Division Multiplexing (OFDM) frames having a time domain and a frequency domain. A method involves inserting in at least one zone of a first type a two dimensional array of data and pilot symbols in time and frequency and inserting in at least one zone of a second type a two dimensional array of data and pilot symbols in time and frequency. In some implementations the zone of the first type includes common pilot symbols that can be detected by all receivers receiving the OFDM frame. In some implementations the zone of the second type includes dedicated pilot symbols that are only detectable by a receiver that is aware of pre-processing used to encode the dedicated pilot symbols.
    Type: Grant
    Filed: August 23, 2006
    Date of Patent: December 6, 2011
    Assignee: Nortel Networks Limited
    Inventors: Jianglei Ma, Ming Jia, Wen Tong, Peiying Zhu, Hang Zhang, Mo-Han Fong
  • Publication number: 20110292838
    Abstract: A method of multicast route computation in a link state protocol controlled network. A spanning tree is computed from a first node to every other node in the network using a known spanning tree protocol. The network is then divided into two or more partitions, each partition encompassing an immediate neighbour node of the first node and any nodes of the network subtending the neighbour node on the spanning tree. Two or more of the partitions are merged when a predetermined criterion is satisfied. Nodes within all of the partitions except a largest one of the partitions are then identified, and each identified node examined to identify node pairs for which a respective shortest path traverses the first node.
    Type: Application
    Filed: August 5, 2011
    Publication date: December 1, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: Jerome CHIABAUT, David ALLAN, Nigel BRAGG
  • Publication number: 20110293028
    Abstract: A method and system for wireless communication in a wireless communication network. The wireless communication network has a first mobile terminal and a second mobile terminal arranged in virtual multiple input, multiple output (“V-MIMO”) communication with a base station. A first wireless communication uplink channel corresponding to the first mobile terminal is estimated. The estimate is based on a first reference symbol signal and the cancellation of interference from a second reference symbol signal received from the second mobile terminal. A second wireless communication uplink channel corresponding to the second mobile terminal is estimated. The estimate is based on the second reference symbol signal and the cancellation of interference from the first reference symbol signal received from the first mobile terminal.
    Type: Application
    Filed: November 12, 2009
    Publication date: December 1, 2011
    Applicant: NORTEL NETWORKS LIMITED
    Inventors: John P. Panicker, Gary D. Boudreau, Michael Petras, Ed Illidge
  • Patent number: 8068876
    Abstract: A method and apparatus for reducing signal interference within a cellular radio system to increase both coverage and capacity. The method and apparatus include altering the direction of beams within cell sectors is among discrete angular positions according to a predetermined, cyclic pattern. The predetermined, cyclic pattern varies in a group of adjacent cell sectors such that inter-cell interference is significantly reduced or eliminated by rotating at a different cycle the beams in adjacent cells. This discrete, angular movement of beams provides for downlink transmissions to be timed in such a way (i.e., scheduled) such that transmission to a user will occur in accordance with the beam and time slot having the best carrier to interference (C/I) ratio for that user.
    Type: Grant
    Filed: February 27, 2007
    Date of Patent: November 29, 2011
    Assignee: Nortel Networks Limited
    Inventors: Nimal Gamini Senarath, Yoon Chae Cheong, Shalini Periyalwar, Robert Matyas