Patents Assigned to Telecom
  • Patent number: 5933547
    Abstract: The invention concerns a method for interpolating images by means of triangulation and geometrical transformation, wherein a triangulation of images and an estimation of movements of apexes is carried out to insert images sub-sampled temporally or steroscopically.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: August 3, 1999
    Assignee: France Telecom
    Inventors: Marie Dudon, Olivier Avaro, Gerard Eude
  • Patent number: 5933258
    Abstract: A discontinuous ring is formed by separate bidirectional optical communication links, with possibly different transmission speeds, synchronous or asynchronous transmission, and ratios of working to protection channels, each linking a pair of terminals in different nodes of a communication system. To protect protection-switched traffic on a communication link from a link failure, it is routed around the ring via the protection channel of the other communication links. To this end, an optical switch is provided between the protection channel of each link and the associated terminals in each node, and is controlled differently in nodes adjacent the link failure and in nodes not adjacent the link failure to route the protection-switched traffic accordingly. Rapid protection switching is facilitated by controlling the optical switches using wavelength detectors directionally coupled to the protection channel at each node.
    Type: Grant
    Filed: September 4, 1996
    Date of Patent: August 3, 1999
    Assignee: Northern Telecom
    Inventors: Thomas P. J. Flanagan, Siraj E. Elahmadi
  • Patent number: 5930335
    Abstract: A method for use in an electronic switching system having more than one operator position system connected thereto, is used for wiretapping in order to determine a time length of a telephone call between a caller and a receiver. The method comprises the steps of: (a) measuring an elapsed time from the instant the caller is connected to the receiver; (b) checking if the elapsed time reaches a preset time; (c) wiretapping when the elapsed time reaches the preset time; (d) resetting the elapsed time and going back to step (a) if the caller is determined to be still on the line by the wiretapping; and (e) releasing the connection between the caller and the receiver if the caller is determined not to be on the line any longer by the wiretapping.
    Type: Grant
    Filed: August 21, 1997
    Date of Patent: July 27, 1999
    Assignee: Daewoo Telecom, Ltd.
    Inventor: Young-Eul Kim
  • Patent number: 5930412
    Abstract: The modulator includes a TE.revreaction.TM converter (3) between two electro-optical modulators (1, 2). The coupler includes two directional couplers interconnected via branches each including a TE.revreaction.TM converter. Another electro-optical component includes a light guide that is folded and metallization that extends at least over two juxtaposed portions of light guide.
    Type: Grant
    Filed: June 18, 1997
    Date of Patent: July 27, 1999
    Assignee: France Telecom
    Inventor: Eric Toussaere
  • Patent number: 5930253
    Abstract: Interworking between narrow band and broad band traffic in an ATM network is provided by a narrow band switch having a point to multipoint capability. Narrow band channels are mapped to time slots in broad band virtual circuits by providing a mapping between channel addresses and virtual circuit payloads. The narrow band traffic is interfaced to the broad band ATM network via a network of adaptive virtual junctors each of which comprises an n.times.64 kbit/s connection so that the cell assembly delay is reduced by a factor of 1/n. this overcomes the assembly delay problem without the need to resort to unproductive padding. Further, by providing dynamic capacity adjustment of the virtual circuits between the junctors, maximum use is made of the available capacity without the need for the permanent reservation of capacity which may be unused for much of the time.
    Type: Grant
    Filed: December 1, 1997
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventors: Simon Daniel Brueckheimer, Roy Harold Mauger
  • Patent number: 5930439
    Abstract: A planar optical waveguide comprises at least two cladding layers on a substrate with at least one core layer disposed between the cladding layers. The overcladding layer of the two layers is doped in order to produce a thermal coefficient of expansion close to or equal to that of the substrate in order to reduce the polarisation sensitivity of the device.
    Type: Grant
    Filed: October 1, 1997
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventors: Sureshchandra Mishrilal Ojha, Terry Bricheno, Clifford Graham Cureton, Stephen Day, David John Moule
  • Patent number: 5930348
    Abstract: An "Intelligent" telecommunications network comprises a plurality of switching units interconnected by links and connected to a central computer unit by a data communication system. For dynamic routing of a call, a first switching unit responds to a destination address in a call to attempt a direct link to a neighboring switching unit and, in the event that the attempt is unsuccessful, issues to the central computer unit a message containing the destination address. The central computer unit uses the destination address to identify the unsuccessful link; (ii) updates a routing database to identify the link as unavailable; (iii) determines an alternative route for the call using a tandem node and (iv) compiles a return message including a network address for a tandem switching unit and transmits it to the first switching unit. The latter attempts to route the call via a link to the tandem unit which attempts to complete the call by a direct link to the destination switching unit.
    Type: Grant
    Filed: March 20, 1997
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventors: Jean Regnier, Jean Choquette, Yvon Archambault
  • Patent number: 5930310
    Abstract: This invention relates to telecommunications systems. The present invention provides a system and method operable to the cancel interference from digital subscriber line systems. A data signal demodulator having first and second inputs arranged to receive differential data signals and local field RFI signals respectively, wherein a digital adaptive notch filter is formed by DSP means which locates an interferer in the differential signal by adapting its bandwidth and center frequency by adaptation means and wherein the center frequency and bandwidth of the notch filter are used to generate a bandpass filter centered on the interferer and of approximate bandwidth to the interferer; whose output, after processing forms a feedback signal which is sampled, processed, weighted and then combined with the local field RFI input signal of the demodulator, which combined signal is summed with the differential input signal to thereby cancel interference coupled onto the first input.
    Type: Grant
    Filed: October 25, 1996
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventor: Benedict Russell Freeman
  • Patent number: 5930305
    Abstract: For combining diversity path signals comprising symbols each modulated in accordance with one of a plurality of orthogonal (e.g. Walsh) functions, a diversity combiner includes, for each path, a demodulator to demodulate each modulated signal symbol in accordance with a selected one of the orthogonal functions, a phase estimator to estimate a phase rotation and amplitude of the diversity path signal from the demodulated signal, and a complex signal multiplier to derotate the phase and weight the amplitude of the diversity path modulated signal in dependence upon the estimated phase rotation and amplitude. The combiner sums real parts of the phase-derotated and weighted modulated signals of the diversity paths, demodulates the combined signal in accordance with all of the orthogonal functions, and selects the maximum demodulated signal for each symbol thereby to determine for the symbol the selected one of the orthogonal functions.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventor: Harry Leib
  • Patent number: 5930341
    Abstract: A browser device and method for interfacing screen-display telephone terminals with the Internet. The browser device located on an ADSI capable telephone platform server, retrieves requested data files from an Internet site and formats the retrieved data file specifically for display on the screen-display telephone terminal.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: July 27, 1999
    Assignee: Northen Telecom, Limited
    Inventors: Raymond A. Cardillo, IV, Thomas Kredo
  • Patent number: 5930278
    Abstract: A multi-wavelength laser-emitting component presenting a plurality of Bragg grating laser-emitting sources, wherein the Bragg gratings of said sources correspond to a diffraction grating common to the various sources, with the pitch thereof varying continuously from one source to another.
    Type: Grant
    Filed: January 28, 1997
    Date of Patent: July 27, 1999
    Assignee: France Telecom
    Inventor: Louis Menigaux
  • Patent number: 5930161
    Abstract: Binary and multiple-valued nonvolatile content addressable memories (NVCAMs) use ferroelectric capacitors as nonvolatile storage elements. The operation of the NVCAMs is accessed either in serial or in parallel. In a 2-bit NVCAM of a parallel access structure, search operation is performed by a simultaneous access to a 4-level polarization of the ferroelectric capacitor. The total number of search operations is reduced.
    Type: Grant
    Filed: July 6, 1998
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventors: Ali Sheikholeslami, P. Glenn Gulak, Takahiro Hanyu
  • Patent number: 5930347
    Abstract: A method of interrupting a call established via an analog link between two terminals via a switching center, whether the call is telephonic, telematic or a combination of the two, comprises the transmission of a user alerting signal and a terminal alerting signal from the switching center to one of the terminals. Between these signals the call between the terminals is re-established. To detect the terminal alerting signal the terminal searches during a predetermined period for a pattern transmitted by the switching center comprising in succession a first silence signal with a power less than a predetermined power during a first predetermined period of silence, the terminal alerting signal, and a second silence signal during a second predetermined period of silence.
    Type: Grant
    Filed: July 22, 1997
    Date of Patent: July 27, 1999
    Assignee: France Telecom
    Inventor: Bernard Louvel
  • Patent number: 5930714
    Abstract: The present invention facilitates an inter-mobile switching center (MSC) soft hand-off by creating a communication link between the MSCs through the base station controllers (BSCs). The routers in the BSCs are linked to form a virtual router. This faster link between the BSCs enables the same protocol to be used for intra-MSC soft hand-off used for inter-MSC soft hand-off.
    Type: Grant
    Filed: October 24, 1996
    Date of Patent: July 27, 1999
    Assignee: Northern Telecom Limited
    Inventors: Marwan Abu-Amara, Steve Sides, Ahmad Jalali, Jyoti Boppana, Satyajit Doctor
  • Patent number: 5926533
    Abstract: A telephone station interface is provided with apparatus for detecting when a called party has or is attempting to patch or bridge one telephone call with another telephone call. The detecting of such bridging or conferencing is accomplished through the detection of tones which are commonly associated with such activities, such as a ring signal, a busy signal, special information tones (SIT tones), dual tone multi-frequency (DTMF) tones or so-called Touch Tones, call progress tones, or other tones that occur when calls are placed. The present invention does not have the capability of sensing clicks, pops, or other audio signals associated with the conferencing of multiple communications circuits. The method and apparatus herein are for managing institutional telephone activity, and utilize a computer control unit to control a trunk management unit, which connects institutional telephones to outside telephone lines.
    Type: Grant
    Filed: October 4, 1996
    Date of Patent: July 20, 1999
    Assignee: Opus Telecom, Inc.
    Inventor: Jay L. Gainsboro
  • Patent number: 5926102
    Abstract: A method for controlling bidirectional line protection switching by using a remote defect indication signal. The method includes the following steps of: inserting and transmitting a remote defect indication signal through the opposite directional link, in case the receiving end of working line detects a defect while a traffic is transmitted via a bidirectional link, and then switching to a back-up line by controlling the selector of the receiving station; and switching to the protection line by controlling the selector of the transmitting station, in case the remote defect indication signal is detected via the opposite directional link.
    Type: Grant
    Filed: July 11, 1997
    Date of Patent: July 20, 1999
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecom
    Inventors: Kyung-Gyu Chun, Yoo-Kyoung Lee
  • Patent number: 5923680
    Abstract: Random bit errors in a digital transmission system in which data is scrambled and subsequently descrambled are detected by parsing the descrambled data into words, determining a syndrome error word for each data word, and determining a parity error word for each data word. A data word is left uncorrected when its corresponding syndrome error and parity error words are both zero. Single bit error correction of a data word is effected when its corresponding syndrome error and parity error words are both non-zero. Double or multiple bit error correction of a data word is effected when its corresponding parity error word is zero and its corresponding syndrome error word is non-zero.
    Type: Grant
    Filed: June 5, 1997
    Date of Patent: July 13, 1999
    Assignee: Northern Telecom Limited
    Inventors: Simon Daniel Brueckheimer, David John Stacey
  • Patent number: 5923738
    Abstract: A screen-display telephone terminal for interfacing with the Internet. A browser device located on an ADSI capable telephone platform server retrieves requested data files from an Internet site and formats the retrieved data file specifically for display on the screen-display telephone terminal. The browser also permits a link between ADSI specific applications by giving the screen-display telephone terminal imbedded softkey commands that may be used to retrieve other data files including ADSI applications.
    Type: Grant
    Filed: July 29, 1997
    Date of Patent: July 13, 1999
    Assignee: Northern Telecom, Limited
    Inventors: Raymond A. Cardillo, IV, Thomas Kredo
  • Patent number: 5923208
    Abstract: A temperature-to-voltage converter includes a first circuit for developing a signal having a positive temperature coefficient and a second circuit for developing a signal having a voltage offset and a negative temperature coefficient. The converter also includes an adder circuit configured to subtract the negative-temperature-coefficient signal from the positive-temperature-coefficient signal. The resulting difference signal is a low voltage that exhibits linear temperature-to-voltage conversion, allowing the converter to be powered by a low operating voltage.
    Type: Grant
    Filed: September 12, 1996
    Date of Patent: July 13, 1999
    Assignee: Telecom Semiconductor, Inc.
    Inventors: Ali Tasdighi, Chuong Nguyen
  • Patent number: 5920237
    Abstract: A constant envelope quadrature-quadrature amplitude modulation system limits the data, which will be transmitted, to 4-bit and adds 4-bit parity to make them have a constant envelope in the Q.sup.2 AM system, which modulates 8-bit in units of 2-bit. The system includes: a constant envelope encoder 52 for adding 4-bit parity to 4-bit input information; four mappers 12 to 15 for respectively generating level signals corresponding to data values of 2-bit among 8-bit data generated by the constant envelope encoder 52; four mixers 16 to 19 for respectively mixing the level signals generated by the four mappers 12 to 15 with different predetermined frequency signals; and adder 20 for adding up the signals generated by the four mixers 16 to 19.
    Type: Grant
    Filed: November 14, 1997
    Date of Patent: July 6, 1999
    Assignee: Daewoo Telecom Ltd
    Inventors: In Jae Park, Woo Hyung Lee