Patents Assigned to Northern Telecom Limited
  • Patent number: 6021328
    Abstract: A method and system is disclosed for triggering handoff of a call from a CDMA network to an AMPS network on which it is overlaid responsive to a determination that the CDMA RF link has degraded to such an extent that the call quality will be degraded significantly or the call is likely to be dropped is disclosed.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: February 1, 2000
    Assignee: Northern Telecom Limited
    Inventors: David E. Curtis, William B. Book, David A. Boettger, Ahmad Jalali
  • Patent number: 6021189
    Abstract: Method for controlling usage of phone debit cards and an associated telephony system which incorporates the same. A switch receives requests to complete telephone calls to destination terminals and to assess fees associated with the requested telephone calls to a phone debit card account. Upon receipt of such a request, the switch asks an SCP to verify that the account is valid and has sufficient credit to complete the requested call. Upon being advised of the same, the switch completes the call. The switch then requests that the SCP deduct the cost of a first minute of the call from the account. When the switch has been advised that the cost of the first minute has been deducted from the account, the switch sets a timer. If the call is continuing when the minute expires, the switch will request that the SCP deduct the cost of the next minute from the account.
    Type: Grant
    Filed: October 27, 1997
    Date of Patent: February 1, 2000
    Assignee: Northern Telecom Limited
    Inventor: Joe Q. Vu
  • Patent number: 6018324
    Abstract: The present invention relates to radio communications antennas. A wide band omnidirectional dipole antenna is described comprising a dipole antenna having first and second quarter wavelength dipole arms, a transmission line from input termination point having a ground and a central conductor; wherein the central conductor is connected to a centrally located feed point on the first dipole arm by the transmission line and the second dipole arm is connected to ground and acts as a ground plane for the transmission line. The present invention can be deployed in fixed and mobile wireless terminals and associated therewith. The antenna design can provide a cost effective solution to many applications.
    Type: Grant
    Filed: October 29, 1997
    Date of Patent: January 25, 2000
    Assignee: Northern Telecom Limited
    Inventor: Dean Kitchener
  • Patent number: 6018625
    Abstract: A management base of a communications network manager is constructed using object oriented techniques. A network comprises a plurality of physical resources in the form of components and assemblies of components, which are distributed across the network. A management system for the network is constructed in an evolutionary manner by representing an overall functionality of the network by an application model in which each function of the network is modeled independently of its implementation, decomposing the application model into an implementation model in which every function represented in the application model is represented in the implementation model, representing the application model as a plurality of objects, representing the implementation model as another plurality of objects, connecting the objects of the application model and implementation model together to obtain a combined object model, and constructing a management base according to the combined object model.
    Type: Grant
    Filed: August 27, 1997
    Date of Patent: January 25, 2000
    Assignee: Northern Telecom Limited
    Inventors: Clive Colin Hayball, Peter Jamieson Tattersfield, Nigel Lawrence Bragg
  • Patent number: 6016340
    Abstract: A billing scheme for a telecommunications network is described in which a billing record for a call including at least a plurality of data bytes is generated in a switch (10), each billing record is duplicated, and check information is generated from each data byte of a billing record and associated with each said data byte to form a protected billing record. Each protected billing record of a duplicated pair is transmitted via two independent transmission lines to processing means (40, 50) in which the associated check information is generated byte-for byte from each received billing record and the generated check information is compared byte-for-byte with the transmitted check information in parity checking circuits (60, 61). If for any one byte of a billing record, the generated check information does not agree with the received check information, that billing record is discarded.
    Type: Grant
    Filed: December 11, 1997
    Date of Patent: January 18, 2000
    Assignee: Northern Telecom Limited
    Inventor: Arsavir Bayraktar
  • Patent number: 6016429
    Abstract: An algorithm or method for ascertaining minimum cellular system costs is presented based on the recognition that the proper distribution of wired network blocking probability is the prime consideration in optimizing system design for minimum cost. System costs are calculated for each of a series of VCs maximum blocking probabilities "b" wherein the total wired network blocking probability is "BP" and the channel element blocking probability for each of those calculations must not exceed "(BP-b))/(1-b)". An examination of the resulting calculations will then reveal the appropriate distribution of resources to minimize costs.
    Type: Grant
    Filed: May 28, 1997
    Date of Patent: January 18, 2000
    Assignee: Northern Telecom Limited
    Inventors: Farid Khafizov, Nikhil Jain, Damodar Anandampillai
  • Patent number: 6016320
    Abstract: In a TDM communications system comprising a base station and a number of outstations, a marshalling signal enables a newly connected outstation to determine the timing of its transmission bursts A detector circuit for recovering the marshalling signal incorporates comparators whose thresholds are adjusted to the high and low levels of the normal data signal. The marshalling signal is recovered from one or other of the comparators according to whether a high or low normal data signal is received, this condition being determined by a third comparator whose threshold is adjusted midway between the high and low level. This allows the marshalling signal to be recovered continuously without interrupting normal data transmission from the outstation.
    Type: Grant
    Filed: February 21, 1997
    Date of Patent: January 18, 2000
    Assignee: Northern Telecom Limited
    Inventor: Paul Douglas Welton
  • Patent number: 6016123
    Abstract: An antenna arrangement (10) for a cellular radio base station is provided with a plurality of r.f. transceivers, including one or more antenna arrays (12) each comprising a plurality of sub-arrays (20) each selectively operpable to form a beam in azimuth. Each sub-army is provided with elevation beamforming means (24) and individual transmit and receive amplifiers (30,32). Each sub-array beamformer is coupled to at least one r.f. transmitter feed (26)nd each r.f. receiver feed is coupled to at least two sub-array beamformers, the sub-arrays of each antenna array together forming a multiplicity of separate substantially coincident beams in azimuth. A method of operation is also disclosed.
    Type: Grant
    Filed: June 24, 1997
    Date of Patent: January 18, 2000
    Assignee: Northern Telecom Limited
    Inventors: Paul Barton, Jeffrey Graham Searle, Peter John Chrystie, Keith Russell Edwards
  • Patent number: 6014440
    Abstract: A method for protocol negotiation between an originating call handler and a terminating call handler, both of which reside within a switching node of a telecommunications network. A call initiated by an originating agency is transmitted to the originating call handler. The originating call handler transfers the call to the terminating call handler which completes the call to a terminating agency. Prior to transfer between handlers, a transfer protocol is determined. If the originating and terminating call handlers share a common native protocol, the common native protocol is selected for transfers therebetween. If the handlers do not share a common native protocol, the native protocol of the originating call handler is selected for transfers therebetween if a non-native protocol of the terminating call handler matches the native protocol of the originating call handler.
    Type: Grant
    Filed: July 21, 1997
    Date of Patent: January 11, 2000
    Assignee: Northern Telecom Limited
    Inventors: Keith W. Melkild, Mark L. Herbert, Brian M. Roeten
  • Patent number: 6014558
    Abstract: A method for implementing variable rate optional security measures in a wireless communications network, the communications network having a plurality of nodes for communication with mobile subscribers, includes the following steps. A capacity constraint of at least one node of the network is first determined. A load list is dynamically maintained for each node as a function of the capacity constraint, the load list indicating any overload states of the nodes. Lastly, at least one optional security measure is performed on the network as a function of the load list, wherein the at least one optional security measure is selected from a plurality of optional security procedures. An apparatus for implementing variable rate optional security measures in a wireless communications network is also disclosed.
    Type: Grant
    Filed: December 28, 1998
    Date of Patent: January 11, 2000
    Assignee: Northern Telecom Limited
    Inventor: Michael Thomas
  • Patent number: 6011513
    Abstract: Digital control of analogue beamformers utilising PIN diodes in a shunt circuit bi-phase attenuator arrangement is difficult because of the diodes extremely non-linear control response. There is disclosed a PIN diode circuit arrangement comprising a digital to analogue converter (DAC) with a reference voltage controller arranged to vary the DACs response to digital input signals to compensate for the PIN diode's non-linear response making this look substantially linear in the digital domain. The circuit preferably incorporates a feedback arrangement from the output of the DAC to its reference voltage input.
    Type: Grant
    Filed: November 23, 1998
    Date of Patent: January 4, 2000
    Assignee: Northern Telecom Limited
    Inventors: Fiona Maihri Wilson, Robin Paul Rickard
  • Patent number: 6011842
    Abstract: The present invention provides an enhanced protocol converter which may be configured as a network element, e.g. a digital switch, a node of the system or a digital private exchange. The network element is for use in a telecommunications network which supports at least one supplementary service and which includes a node, a message associated with a supplementary service being transmittable within the network including an information element in a first format which is incompatible with the node, and a message associated with a supplementary service being transmittable within the network including an information element in a second format compatible with the node.The network element examines the messages and determines if the format of an information element therein is compatible with the next node. If it is, the message is transmitted transparently. If not, the format is changed to the appropriate format for the next node and for the relevant supplementary service.
    Type: Grant
    Filed: December 24, 1997
    Date of Patent: January 4, 2000
    Assignee: Northern Telecom Limited
    Inventors: Mayeul Brivet, Loic Conan
  • Patent number: 6009321
    Abstract: A system and method for tracing calls, such as those terminating in a wireless telephone system, is disclosed. The system is part of a communication network that uses a switch connected to a caller. The switch extracts information about the caller such as a calling party number and other information useful for tracing the call. Once the information has been extracted, the switch sends the information to a storage device associated with the called party, such as a home location register. The storage device creates a log of the call, storing all the extracted information. When the call is to be traced, a device capable of accessing the storage device can easily retrieve the stored information and thereby identify and locate the caller.
    Type: Grant
    Filed: July 7, 1997
    Date of Patent: December 28, 1999
    Assignee: Northern Telecom Limited
    Inventors: Jin Wang, Maria Hemmer, Yahya Idrissi, David Wilding
  • Patent number: 6009431
    Abstract: Disclosed is an apparatus for quickly generating an error free MIB file of the type used by a SNMP manager to manage and display error and log trap messages received from agents reporting to said manager. This is accomplished by retrieving data from definition and template libraries to be used in conjunction with a network element database to correctly generate, element by element, a completed MIB file.
    Type: Grant
    Filed: March 31, 1998
    Date of Patent: December 28, 1999
    Assignee: Northern Telecom Limited
    Inventors: Thomas J. Anger, Shing Yu Yeung, Joyce Bradley, Steven J. Crossley
  • Patent number: 6006182
    Abstract: Systems and methods consistent with the present invention determine whether to accept one of a plurality of intermediate recognition results output by a speech recognition system as a final recognition result. The system first combines a plurality of speech rejection features into a feature function in which weights are assigned to each rejection feature in accordance with a recognition accuracy of each rejection feature. Feature values are then calculated for each of the rejection features using the plurality of intermediate recognition results. The system next computes the feature function according to the calculated feature values to determine a rejection decision value. Finally, one of the plurality of intermediate recognition results is accepted as the final recognition result according to the rejection decision value.
    Type: Grant
    Filed: September 22, 1997
    Date of Patent: December 21, 1999
    Assignee: Northern Telecom Limited
    Inventors: Waleed Fakhr, Serge Robillard, Vishwa Gupta, Real Tremblay, Michael Sabourin, Jean-Francois Crespo
  • Patent number: 6005859
    Abstract: System and method for extending the use of a VAT telephony application to originate calls into a PSTN as well as a computer network are disclosed. In a preferred embodiment, an adjunct application, referred to as a VAT signaling program ("VSP") running on the same host computer as a conventional VAT-based telephony application prompts a user to enter a destination telephone number and uses the entered number to generate a Q.931 SETUP message, which is encapsulated in a nonstandard, undefined, VAT control message (the "VAT Q.931 message") created to enable additional signaling information to be sent. A signaling interface to the PSTN serving the designated telephone number signals to the VAT application software exactly as if the signaling interface were actually another VAT application software originating a call to the naive VAT application. The signaling interface waits until the user at the computer "answers," and then originates the call into the PSTN network.
    Type: Grant
    Filed: December 19, 1996
    Date of Patent: December 21, 1999
    Assignee: Northern Telecom Limited
    Inventors: Joseph Harvell, Gregory T. Stovall
  • Patent number: 6005874
    Abstract: In a secure communications system where messages between subscribers are encrypted according to a selection of encryption procedures, a gateway trunk is provided. The gateway trunk comprises a telecommunications trunk (35) with one or more cryptographic devices (A,B,C) inserted in each traffic channel and a separate signaling channel (37), and a traffic channel is selected according to a code dialed by a subscriber. The gateway trunk may be associated with a PABX (31) such that messages are routed through a channel of the trunk corresponding to the cryptographic device required. Pairs of different cryptographic devices may be inserted in each channel of the trunk to effect conversion from one encryption procedure to another.
    Type: Grant
    Filed: August 18, 1997
    Date of Patent: December 21, 1999
    Assignee: Northern Telecom Limited
    Inventor: Martin Sharpe
  • Patent number: 6005842
    Abstract: An engineering order wire arrangement is provided for a synchronous telecommunications network comprising a plurality of nodes interconnected via transmission paths, each path accommodating a plurality of transmission channels. Engineering voice traffic is carried on a first overhead channel having a defined network route topology. A second overhead channel is used to define a model network having a a route topology identical to that of the first overhead channel. The model network is tested to determine its integrity, i.e. the absence of loops. If the model network is found to be defective, both networks are reconfigured.
    Type: Grant
    Filed: June 26, 1997
    Date of Patent: December 21, 1999
    Assignee: Northern Telecom Limited
    Inventors: David Michael Goodman, Adonios Bitzanis, Dino Cosimo DiPerna, Clifford Townsend
  • Patent number: 6005927
    Abstract: An apparatus and method for maintaining records in a telephone directory involves maintaining a personal directory of at least one record associated with at least one party with which a telephone call is conducted. The record has a field for identifying the party and a frequency of use field for storing a number representing the number of times a call is conducted with the party. In response to a call conducted with a party, the personal directory is searched for a record associated with the party and upon finding such a record, the contents of the frequency of use field of the record are incremented and the records of the personal directory are sorted in an order dependent upon the contents of the frequency of use fields.
    Type: Grant
    Filed: December 16, 1996
    Date of Patent: December 21, 1999
    Assignee: Northern Telecom Limited
    Inventors: Timothy Joseph Rahrer, Robert Scott McClennon, David Robert Cuddy
  • Patent number: D418074
    Type: Grant
    Filed: July 8, 1998
    Date of Patent: December 28, 1999
    Assignee: Northern Telecom Limited
    Inventors: Mark Edward Hicks, Stephen Kenneth Cooper, Richard Edward Hughes