Patents Assigned to Telecom
  • Patent number: 5910753
    Abstract: A universal synchronizer for use in a variety of telecommunications systems based on direct digital phase synthesis (DDPS) include digital and analog PLLs. The synchronizer may be used for wireless, optical, or wireline transmission systems and for a wide ranges of data rates. Digital phase detectors are used in the digital PLLs for comparing the phase of the local clock f.sub.L with the phase of a respective digital reference clock, and provides a respective phase error signal. A digital phase synthesis unit receives the phase error signal and a target phase error and produces a first and a second set of control signals for driving an error driver. The error driver generates the control voltage for adjusting the frequency of a VCXO that is used for all PLLs, to lock the respective PLL. The first set of control signal generates the control voltage for the digital PLLs, and the second set of control signals generates the control voltage for the analog PLLs and for the acquisition mode of operation of all PLLs.
    Type: Grant
    Filed: September 19, 1997
    Date of Patent: June 8, 1999
    Assignee: Northern Telecom Limited
    Inventor: Wladyslaw Bogdan
  • Patent number: 5910990
    Abstract: An apparatus for automatically equalizing a personal multi-channel audio system, and a method therefor, are disclosed. White noises which are generated by a transfer characteristic measuring section are reproduced through speakers. Transfer signals from the respective speakers are collected through a microphone array at a listening position so as to transmit the collected signals to a transfer function calculating section. The transfer function calculating section calculates the transfer characteristics between the respective speakers and the listening position by utilizing the white noise and the collected signals. Then the sound characteristics of the respective sound channels are adjusted so that the transfer characteristics between the respective speakers and the listening position would be equalized. Further, phantom channels are synthesized and reproduced by utilizing the transfer functions and the installed speakers. Therefore, at the given environment, an optimum sound reproduction is obtained.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: June 8, 1999
    Assignees: Electronics and Telecommunications Research Institute, Korea Telecom
    Inventor: Dae-Young Jang
  • Patent number: 5910906
    Abstract: The invention is a method for performing tone detection on a digital signal processor (DSP) that may be used in the presence of tone aliases caused by inadequate anti-aliasing filtering. The method involves processing an input signal at different sampling rates, and can be used with any tone detection algorithm. A tone is detected when it is present at each of the sampling rates. The method allows tone detection to be performed without the use of a proper anti-aliasing filter.
    Type: Grant
    Filed: July 25, 1996
    Date of Patent: June 8, 1999
    Assignee: Northern Telecom Limited
    Inventor: Ronald Frederick Schmitt
  • Patent number: 5909065
    Abstract: A system for limiting power supply transients in a powered up backplane when a printed circuit (PC) board is plugged in. The PC board includes first connecting pins with different lengths connecting to precharge planes on the backplane where each sequentially longer pin length is connected to a precharge plane providing a sequentially lower voltage. The first connecting pins are further connected by precharge circuits to power planes on the PC board. The precharge circuits are configured to ramp current to minimize power supply transients. In one embodiment, the precharge circuits each include a transistor and RC circuit connecting each first connecting pin to a power plane on the PC board.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: June 1, 1999
    Assignee: DSC Telecom L.P.
    Inventors: James Jones, Jason W. Dove
  • Patent number: 5909430
    Abstract: An ATM switched network has an ATM switch, an address server, and a plurality of nodes connected through virtual connections established by the ATM switch. When a node fails and is replaced, the ATM switch recognizes the installation of the node and notifies the address server. The address server selects an ATM address for the replacement node and sends the ATM address and an Internet Protocol (IP) address to the node. The node responds by requesting configuration data, which the address server downloads to the node. Thereafter, the node may initialize its communication interfaces within the ATM network. The address server also assigns ATM and IP addresses to network nodes following power-up of the network. Nodes are assigned an ATM address and an IP address by the address server, thereby eliminating the need to configure nodes with addressing information during manufacture or installation.
    Type: Grant
    Filed: December 31, 1996
    Date of Patent: June 1, 1999
    Assignee: Northern Telecom Limited
    Inventor: James Edwin Reaves
  • Patent number: 5909648
    Abstract: A network interface terminates communication between a disconnecting party (i.e., requesting a disconnect from the network interface) and a disconnected party in communication with the disconnecting party. The disconnecting and disconnected parties are connected to first and second networks, respectively. When receiving a disconnect request from the disconnecting party, the network interface initiates communication termination for the disconnecting party. If there is no buffered data to be transmitted to the disconnected party, the interface begins communication termination for the disconnected party. Otherwise, the interface transmits the buffered data to the disconnected party and then initiates communication termination for the disconnected party.
    Type: Grant
    Filed: April 11, 1996
    Date of Patent: June 1, 1999
    Assignee: Northern Telecom Limited
    Inventors: Paul Henry Boudreaux, Terry Wayne Bush, Justin Medlock
  • Patent number: 5909574
    Abstract: A computing system in which permanent state changes to portions of the system are effected using transactions, including an exception handier and a method of handling exceptions in such a system is disclosed. Specifically, the computing system comprises a processor for executing at least one process; and scratchpad memory. A transactional subsystem is interconnected with the processor and has a plurality of states. State changes to the transactional subsystem are made irreversible only upon successful completion of a transaction. Program memory interconnected with the processor contains an exception handler for handling an exception dependent on one of a transaction. The handler adapts the processor to buffer data resulting from the exception in the scratchpad memory; and upon successful completion of the transaction, transfer the buffered data to an exception buffer accessible by a software process executing on the processor.
    Type: Grant
    Filed: December 23, 1997
    Date of Patent: June 1, 1999
    Assignee: Northern Telecom Limited
    Inventor: Peter A. Meyer
  • Patent number: 5909485
    Abstract: To limit the risk of unpaid telephone calls to be set up from a predetermined terminal via a switched telephone network, a prepayment for consumption of such calls comprises setting up a call from any terminal to a prepayment server via the switched telephone network in order to transmit a message identifying the predetermined terminal to the prepayment server; responsive to identification of the predetermined terminal, requesting from the calling terminal prepayment of telephone call consumption to the prepayment server; and, if the prepayment request is accepted by the prepayment server, paying an amount transmitted from the calling terminal so that the payment server increments a consumption count associated with the predetermined terminal. The predetermined terminal and any terminal can be one and the same mobile phone terminal connected to the switched telephone network via a mobile phone network.
    Type: Grant
    Filed: March 7, 1997
    Date of Patent: June 1, 1999
    Assignee: France Telecom
    Inventors: Daniel Martin, Christian Grezes, Annick Seghers
  • Patent number: 5909466
    Abstract: The equalizer circuit for the receiver of a digital communications system is characterized in that its predictor (11) is purely recursive, its phase equalizer (12) is purely transversal, and the relative positions of those two elements are interchangeable, means for evaluating performance in terms of decision error and for causing the two elements to be interchanged in application of a criterion for evaluating the difficulty of reception, the predictor being upstream and optimized in adaptive and self-learning manner to whiten its own output while the phase equalizer (12) is downstream and optimized in adaptive manner during periods of difficult reception, whereas the predictor (11) is downstream and the phase equalizer (12) is upstream, both being optimized jointly in adaptive manner to minimize decision error between the output (d(n)) of the decision circuit (2) and its input (w(n) or y(n)) during periods of easy reception.
    Type: Grant
    Filed: February 7, 1997
    Date of Patent: June 1, 1999
    Assignee: France Telecom
    Inventors: Joel Labat, Christophe Laot, Odile Macchi
  • Patent number: 5907810
    Abstract: A method for reducing the paging load in a cellular communication system is described. The cell C with the largest paging load L is first identified. Since this cell is usually included in more than one paging zone, the paging zones including cell C are identified. Thereafter, cell C is removed tentatively from each identified zone and a ratio R calculated which represents the decrease in loading on cell C due to being removed from zone z divided by the maximum increase in loading on any other cell in the network. The zone for which the ratio R is the largest is the best candidate for removing cell C therefrom. After doing so tentatively, the cell C' with the largest paging load L' thereon is identified. If the loading L is greater than L', cell C is removed permanently from the zone having the highest ratio R therefor and the process is repeated until L' is greater than L at which point the process is stopped without removing cell C from the zone with the highest ratio R.
    Type: Grant
    Filed: November 6, 1996
    Date of Patent: May 25, 1999
    Assignee: Northern Telecom Limited
    Inventors: Sairam Subramanian, Seshu R. Madhavapeddy, Alexander J. Montoya, Hee C. Lee, Steven J. Currin, Falguni Sarkar
  • Patent number: 5907609
    Abstract: An electronic switching system processes a plurality of special services (SS's) by storing code schemes in a first storage, receiving input data and converting the received input data into a set of input codes, detecting an identification code among the input codes, retrieving a code scheme corresponding thereto from the first storage, comparing the input codes and the code elements included in the code scheme to produce a SS result, which includes the SS data, when a format of the input codes coincides with the one defined by the code scheme, and storing the SS result in a second storage.
    Type: Grant
    Filed: November 21, 1996
    Date of Patent: May 25, 1999
    Assignee: Daewoo Telecom Ltd.
    Inventor: Gye-Min Jeon
  • Patent number: 5907537
    Abstract: An OA&M system is provided for a network communication core having a switch, a controller, and a core configuration memory. All configuration information which is static (i.e., information which remains the same regardless of the configuration of the core) is placed off-core in a map file. Because of this, requests for information on the configuration of the core may often be satisfied without the need to query the core, thereby reducing core load. Further, this static information in the map file allows validation of requests for dynamic configuration information as well as requests for reconfiguration of the core. In other words, the static information assists in ensuring that requests are proper. The static information in the map file is presented as "list", "attribute", and "choice" features. This presentation facilitates the making of OA&M requests by a user. The features become arguments of functions in order to generate OA&M requests to the controller.
    Type: Grant
    Filed: July 18, 1997
    Date of Patent: May 25, 1999
    Assignee: Northern Telecom Limited
    Inventors: Mario R. J. Papineau, Christopher R. Solar, Pierre A. Hamel, Eric Fredine, Ian W. Olthof, Mathew N. Perkins
  • Patent number: 5907654
    Abstract: A structure of a printed circuit board and a fiber storage holder for accommodating a superfluous length of fiber to be connected to a terminal on the printed circuit board. This structure if for use with the board mounted within an electronic shelf and solely accommodates superfluous lengths of fiber with pre-specified lengths. To enable removal of the printed circuit board from its shelf, free fiber is necessary. This is accommodated by a fiber storage facility which is additional to the holder. The fiber storage facility is located outside the printed circuit board receiving chamber of the shelf and is preferably attached to a shelf wall, e.g. a bottom wall, so as to store a removable length portion of fiber. Upon removal, the removable length portion provides a free fiber length which, by flexing, allows for removal from and return to the shelf of the printed circuit board.
    Type: Grant
    Filed: August 13, 1997
    Date of Patent: May 25, 1999
    Assignee: Northern Telecom Limited
    Inventors: David Stephen John Render, Eric MacDonald, Stephen Macklin
  • Patent number: 5907645
    Abstract: The modulator is formed by a smectic chiral ferroelectric C* liquid crystal cell (CL), crossed by the light signal which is transmitted by the said fibre. The cell (CL) is provided with transparent walls and transparent command electrodes (5 to 7). The liquid crystal (CL), used in half-wave mode, is of the SSFLC (surface stabilized ferroelectric liquid crystal) type, having a wide tile angle .theta., which is as close as possible to 45.degree., in such a way that the said modulator is insensitive to polarisation. The modulator may be connected to two parallel fibres (A2, A3; B2, B3), pertaining to the intermediary part of a Mach-Zehnder coupler between the two 3 dB couplers, and when it is provided in order to modulate the light signal transmitted by either one of the two fibres.
    Type: Grant
    Filed: December 23, 1996
    Date of Patent: May 25, 1999
    Assignee: France Telecom
    Inventors: Laurent Dupont, Jean-Louis de Bougrenet de la Tocnaye, Michel Monerie
  • Patent number: 5905789
    Abstract: Subscribers to a personal telephone number service can receive calls placed to telephone numbers associated with an individual rather than a physical location or telephone line. A subscriber predefines a set of telephone numbers for telephones at locations frequented by the subscriber. When a call to a subscriber's personal telephone number is received, a model of the subscriber's behavior predicts the likelihood of the subscriber being at different locations, and the call is forwarded to a telephone at the most likely location, given the current day of the week and time of the day. The model is trained using data obtained by cases in which a caller calling the personal telephone number is successful in locating the subscriber.
    Type: Grant
    Filed: February 26, 1997
    Date of Patent: May 18, 1999
    Assignee: Northern Telecom Limited
    Inventor: Craig Alexander Will
  • Patent number: 5905755
    Abstract: Method and circuit for deciding whether or not a pulse in a data stream is or is not a valid pulse of the data stream, wherein a free-running local clock at N-times the data rate is generated and clock pulses thereof are counted once the data stream signal reaches and remains above a slicing threshold. Once a predetermined minimum number of counted clock pulses is attained a valid data pulse signal is issued.
    Type: Grant
    Filed: July 17, 1996
    Date of Patent: May 18, 1999
    Assignee: Northern Telecom Limited
    Inventor: Manfred Ficker
  • Patent number: 5905551
    Abstract: An upper case and a lower case are fixed without using screws so that assemblage workability is improved. An electric appliance can be divided into plastic upper case, metal-plate-made lower case, and logic package having print substrates. As a result, the electric appliance is easy to make.
    Type: Grant
    Filed: December 10, 1997
    Date of Patent: May 18, 1999
    Assignee: Hitachi Telecom Technologies Ltd.
    Inventors: Kazuo Sanpei, Tatsuo Yamauchi
  • Patent number: 5905773
    Abstract: A method of reducing the perplexity of a speech recognition vocabulary and dynamically selecting speech recognition acoustic model sets used in a simulated telephone operator apparatus. The directory of users of the telephone network is subdivided into subsets wherein each subset contains the names of users within a certain location or exchange. A speech recognition vocabulary database is compiled for each subset and the appropriate database is loaded into the speech recognition apparatus in response to a requested call to the location covered by the subset. Furthermore, a site-specific acoustic model set is dynamically loaded according to the location of a calling party. An apparatus for carrying out the method is also discussed.
    Type: Grant
    Filed: March 28, 1996
    Date of Patent: May 18, 1999
    Assignee: Northern Telecom Limited
    Inventor: Chi Wong
  • Patent number: 5905818
    Abstract: For providing a digital representation of an optical scene, radiometric values of N.times.N points representing a real two-dimensional optical scene are measured in the form of N.times.N respective electric signals x(i,j). N.times.N masks Mnm(i,j) respectively associated with the N.times.N electric signals x(i,j) are generated. For each couple (n,m), the N.times.N electric signals x(i,j) are weighted by the corresponding N.times.N masks Mnm(i,j) and the weighted electric signals are added to obtain N.times.N coefficients of the Walsh-Hadamard transform representing the optical scene.
    Type: Grant
    Filed: March 17, 1997
    Date of Patent: May 18, 1999
    Assignee: France Telecom
    Inventor: Yang Ni
  • Patent number: D410645
    Type: Grant
    Filed: March 17, 1998
    Date of Patent: June 8, 1999
    Assignee: Northern Telecom Limited
    Inventors: Todd Andrew Wood, Neal T. Cowan