1
Vasu Iyengar, Rafi Rabipour, Paul Mermelstein, Brian R Shelton: Speech bandwidth extension method and apparatus. Northern Telecom, Dallas F Smith, John A Granchelli, October 3, 1995: US05455888 (184 worldwide citation)

A speech bandwidth extension method and apparatus analyzes narrowband speech sampled at 8 kHz using LPC analysis to determine its spectral shape and inverse filtering to extract its excitation signal. The excitation signal is interpolated to a sampling rate of 16 kHz and analyzed for pitch control a ...


2
Vishwa N Gupta, Matthew Lennig: Speech recognition method using a two-pass search. Northern Telecom, Dallas F Smith, John A Granchelli, May 7, 1996: US05515475 (178 worldwide citation)

A method of recognizing speech comprises searching a vocabulary of words for a match to an unknown utterance. Words in the vocabulary are represented by concatenated allophone models and the vocabulary is represented as a network. On a first pass of the search, a one-state duration constrained model ...


3
Edmond J Helstab, Jeffrey L Fairless, Michael C G Lee, Neal T Cowan, Jonathan Crone, Edward L Pugh, Robert E Bradley: Desktop docking station for use with a wireless telephone handset. Nortel Networks Corporation, Jean Pierre Fortin, Dallas F Smith, June 6, 2000: US06073031 (170 worldwide citation)

A telephone base unit for use with a mobile telephone handset comprises means for interfacing the handset with the base unit for enabling user definable data entry key settings of the handset to be downloaded and emulated at the base unit such that when interfaced with the base unit, the mobile tele ...


4
Alan F Graves, Robert C Dittburner, Barry B Hagglund: Video signal distribution system. Northern Telecom, R John Haley, Dallas F Smith, February 19, 1991: US04994909 (130 worldwide citation)

A signal distribution system is disclosed for distributing television program signals from a central location to a plurality of subscriber locations via respective optical fibers. At the central location, 4 of 64 signals are selected and multiplexed for delivery to each subscriber location. At each ...


5
Vishwa N Gupta, Matthew Lennig, Patrick J Kenny, Christopher K Toulson: Phoneme based speech recognition. Bell Canada, Dallas F Smith, February 14, 1995: US05390278 (114 worldwide citation)

A flexible vocabulary speech recognition system is provided for recognizing speech transmitted via the public switched telephone network. The flexible vocabulary recognition (FVR) system is a phoneme based system. The phonemes are modelled as hidden Markov models. The vocabulary is represented as co ...


6
Petre Popescu: Second order active filters. Northern Telecom, R John Haley, Dallas F Smith, April 9, 1991: US05006810 (91 worldwide citation)

A family of second order active filters is described. A general form of the filter comprises an input terminal, an output terminal, and a common terminal, a first reactance and a resistance coupled in series between the input and common terminals, a first emplifier coupled from a connection point be ...


7
Rungnoj Kositpaiboon, Richard Breault, Van P T Phung: Method of providing reserved bandwidth in a dual bus system. Northern Telecom, Dallas F Smith, March 19, 1991: US05001707 (90 worldwide citation)

A method provides reserved bandwidth in a system having dual unidirectional and oppositely oriented buses. The method is intended to enhance the proposed standard, DQDB Metropolitan Area Network. A portion of the bandwidth shared by the stations in accordance with the proposed standard is reserved f ...


8
Shawn Searles, Richard G Kusyk: Signal delay apparatus employing a phase locked loop. Northern Telecom, Dallas F Smith, January 12, 1993: US05179303 (62 worldwide citation)

An apparatus is provided for delaying digital data signals by fixed amounts within an integrated circuit. A delay lock loop includes an adaptive delay line, a phase detector and an integrator. The integrator provides control signals c.sub.p, c.sub.n for controlling the delay line, in dependence upon ...


9
Shawn Searles, Richard G Kusyk: Signal delay apparatus employing a phase locked loop. Northern Telecom, Dallas F Smith, September 8, 1992: US05146121 (58 worldwide citation)

An apparatus is provided for delaying digital data signals by fixed amounts within an integrated circuit. A delay lock loop includes an adaptive delay line, a phase detector and an integrator. The integrator provides control signals c.sub.p, c.sub.n for controlling the delay line, in dependence upon ...


10
Farideh Khaleghi, Alan Glen Solheim, Chris Wilhelm Barnard: Method and apparatus for channel equalization in wavelength division multiplexed systems. Nortel Networks Corporation, Dallas F Smith, March 21, 2000: US06040933 (55 worldwide citation)

A method and apparatus for channel performance equalization in wavelength division multiplexed (WDM) systems is disclosed. Performance of the channels is estimated from optical power measurements of each signal transmitted by the channels. The measurements are taken at the inputs of optical amplifie ...