Patents Represented by Attorney Linli L. Golden
  • Patent number: 6108364
    Abstract: A method and apparatus for time division duplex (TDD) repeating a spread spectrum signal, where spread spectrum signal is comprised of a series of code symbol modulated with a pseudonoise (PN) sequence. The TDD repeater receives intermittently the spread spectrum signal at a location remote from a source supplying the spread spectrum signal. The TDD repeater amplifies and delays the received spread spectrum signal by a predetermined amount. The TDD repeater transmits intermittently the delayed amplified received spread spectrum signal such that the TDD is not receiving the spread spectrum signal when it is transmitting the signal energy.
    Type: Grant
    Filed: August 31, 1995
    Date of Patent: August 22, 2000
    Assignee: Qualcomm Incorporated
    Inventors: Lindsay A. Weaver, Jr., Franklin P. Antonio, Richard F. Dean
  • Patent number: 5956683
    Abstract: A voice recognition system having a feature extraction apparatus is located in a remote station. The feature extraction apparatus extracts features from an input speech frame and then provides the extracted features to a central processing station. In the central processing station, the features are provided to a word decoder which determines the syntax of the input speech frame.
    Type: Grant
    Filed: April 4, 1996
    Date of Patent: September 21, 1999
    Assignee: QUALCOMM Incorporated
    Inventors: Paul E. Jacobs, Chienchung Chang
  • Patent number: 5915235
    Abstract: The present invention teaches an equalizer preprocessor for a mobile telephone speech coder that adapts to the characteristics of its input transducer. The equalizer determines the frequency response of the input transducer by measuring the long term characteristics of the input signal and estimating the spectral envelope of that signal. The equalizer then adapts so that the output signal has a spectral response closer to a perceptually ideal response in accordance with the calculated spectral envelope. In a first embodiment of the present invention, the adaptive equalizer is implemented using digital filtering techniques. The equalizer determines a set of long term autocorrelation coefficient values and from these values generates a set of filter taps which serve to whiten or flatten the spectral response of the input signal. This whitened signal is then passed through a target filter which impresses upon the whitened signal the target spectral response.
    Type: Grant
    Filed: October 17, 1997
    Date of Patent: June 22, 1999
    Inventors: Andrew P. DeJaco, John A. Miller
  • Patent number: 5903862
    Abstract: When one vocoding system is coupled to another vocoding system, a tandem arrangement results. The tandem configuration results in voice quality degradation as speech is encoded and decoded, then encoded and decoded again. One reason for the degradation is that postfiltering performed at the output of the speech decoding process introduces distortions in the spectral content of the reconstructed speech as compared to the original speech. The present invention prevents the degradation due to the use of postfilters by modifying the postfiltering within the vocoders where a tandem configuration exists. A detection code is embedded within the data signal to indicate the existence of a tandem configuration. If the detection code is received at a vocoder, modified vocoding is established within the vocoders to prevent the degradation due to the postfiltering.
    Type: Grant
    Filed: January 11, 1996
    Date of Patent: May 11, 1999
    Inventors: Lindsay A. Weaver, Jr., S. Katherine Lam, William R. Gardner, Paul E. Jacobs, Andrew P. DeJaco, Gilbert C. Sih
  • Patent number: 5861844
    Abstract: A system and method for using a sectored antenna arrangement within a cellular base station to provide redundant coverage within the surrounding cell is disclosed herein. An antenna feed network connects elements of the sectored antenna arrangement to a set of communication transceivers, wherein the feed network includes a combiner array for combining selected ones of the antenna beams upon failure of one of the communication transceivers. A switch network serves to provide the resultant combined beam to an operative one of the communication transceivers.Alternately, the sectored antenna arrangement includes an antenna array having a plurality of switchable antenna elements, each connected to one of the communication transceivers. The switchable antenna elements project a set of variable-width antenna beams over the plurality of cell sectors.
    Type: Grant
    Filed: November 29, 1994
    Date of Patent: January 19, 1999
    Assignee: QUALCOMM Incorporated
    Inventors: Robert P. Gilmore, Daniel Laramie
  • Patent number: 5854786
    Abstract: A packet switching architecture provides for a switch system comprised of a cellular base station in communication with the PSTN through a switch. Data packets are routed through the switch system as necessary to effect communication between the public switched telephone network (PSTN) and mobile radiotelephones disposed within the cellular coverage area surrounding the base station. A packet interconnection subsystem operates to transfer data packets between a plurality of interface ports, to which are coupled a corresponding plurality of signal lines. Within the interconnection subsystem, one or more distribution/consolidation (DISCO) interface units are mutually coupled together through a central router unit. Each DISCO interface unit is configured to consolidate the data packets received through at least two signal ports onto a consolidation bus, as well as to distribute the addressed data packets from a distribution bus to two or more of ports.
    Type: Grant
    Filed: August 9, 1995
    Date of Patent: December 29, 1998
    Assignee: QUALCOMM Incorporated
    Inventors: Eric L. Henderson, Houtan Dehesh, Farrokh Khatibi, Richard Larson, Todd R. Sutton, Lindsay A. Weaver, Jr., Kendrick Hoy Leong Yuen
  • Patent number: 5844899
    Abstract: To provide an unique call ID number in a system comprised of a plurality of entities through which a connection may be established, each entity through which a connection can be initiated is capable of assigning a unique number to a new connection. For example a first entity receives a first request to initiate a first connection and assigns a first unique number to said first connection. The first unique number comprises the identity of the first entity, a time at which the first request was received, a distinction of the first request from any other request received at the first entity in a time block during which said first request was received, and an indication of a system with which the first entity is associated.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: December 1, 1998
    Assignee: QUALCOMM Incorporated
    Inventors: Robert S. Daley, Alejandro R. Holcman, Barry R. Robbins, Noam A. Ziv
  • Patent number: 5790632
    Abstract: An improved method and apparatus for canceling echo is disclosed. The echo canceller of the present invention compensates for the existence of quantization error in the echo signal that does not exist in the reference signal by introducing the quantization effects into the reference signal. The quantization effects are typically companding quantization errors caused by the A-law and .mu.-law quantizers prevalent in digital communications equipment.
    Type: Grant
    Filed: May 21, 1996
    Date of Patent: August 4, 1998
    Assignee: Qualcom Incorporated
    Inventors: Franklin P. Antonio, Andrew P. DeJaco, Gilbert C. Sih
  • Patent number: 5784406
    Abstract: A method and apparatus for characterizing a communications link. An apparatus is disclosed for performing a series of tests that measure delay time, frequency response, background noise, frame error rate and sample slipping and repetition measurements. A signal generator generates a series of signal optimally selected for the particular test. The generated signal is transmitted through the communication system and then sent back through the system by a loop back element remotely placed. The return signal is then analyzed by a monitor means.
    Type: Grant
    Filed: June 29, 1995
    Date of Patent: July 21, 1998
    Assignee: Qualcom Incorporated
    Inventors: Andrew P. DeJaco, Serge D. Willenegger, Paul E. Jacobs
  • Patent number: 5778338
    Abstract: An apparatus and method for performing speech signal compression, by variable rate coding of frames of digitized speech samples. The level of speech activity for each frame of digitized speech samples is determined and an output data packet rate is selected from a set of rates based upon the determined level of frame speech activity. A lowest rate of the set of rates corresponds to a detected minimum level of speech activity, such as background noise or pauses in speech, while a highest rate corresponds to a detected maximum level of speech activity, such as active vocalization. Each frame is then coded according to a predetermined coding format for the selected rate wherein each rate has a corresponding number of bits representative of the coded frame. A data packet is provided for each coded frame with each output data packet of a bit rate corresponding to the selected rate.
    Type: Grant
    Filed: January 23, 1997
    Date of Patent: July 7, 1998
    Assignee: QualComm Incorporated
    Inventors: Paul E. Jacobs, William R. Gardner, Chong U. Lee, Klein S. Gilhousen, S. Katherine Lam, Ming-Chang Tsai
  • Patent number: 5754733
    Abstract: A novel and improved method and apparatus for encoding line predictive coding (LPC) data in a speech compression system using line spectral square root values is disclosed. A novel and computationally efficient procedure for determining the set of quantization sensitivities for the line spectral square root values is disclosed, which results in a computationally efficient error measure for use in vector quantization of the line spectral square root values. A novel method of weighting the quantization error is disclosed, which accumulates the quantization error in each line spectral square root value and weights that error by the sensitivity of that line spectral square root value.
    Type: Grant
    Filed: August 1, 1995
    Date of Patent: May 19, 1998
    Assignee: Qualcomm Incorporated
    Inventors: William R. Gardner, Sharath Manjunath, Peter A. Monta
  • Patent number: 5742734
    Abstract: It is a first objective of the present invention to provide a method by which to reduce the probability of coding low energy unvoiced speech as background noise. The present invention determines an encoding rate by examining subbands of the input signal, by this method unvoiced speech can be distinguished from background noise. A second objective of the present invention is to provide a means by which to set the threshold levels that takes into account signal energy as well as background noise energy. In the present invention, the background noise is not used to determine threshold values, rather the signal to noise ratio of an input signal is use to determine the threshold values. A third objective of the present invention is to provide a method for coding music passing through a variable rate vocoder. The present invention examines the periodicity of the input signal to distinguish music from background noise.
    Type: Grant
    Filed: August 10, 1994
    Date of Patent: April 21, 1998
    Assignee: Qualcomm Incorporated
    Inventors: Andrew P. DeJaco, William R. Gardner
  • Patent number: 5732134
    Abstract: A method and apparatus are described for detecting doubletalk in an acoustic echo canceller. The present invention examines the spectral characteristic of the near-end audio signal and the spectral characteristics of the far-end audio signal and determines from the comparison if a condition of doubletalk exists. An exemplary implementaion of the present invention is presented in an acoustic echo canceller wherein the adaptation of the adaptive filter taps is inhibited during periods of doubletalk.
    Type: Grant
    Filed: January 15, 1997
    Date of Patent: March 24, 1998
    Assignee: Qualcomm Incorporated
    Inventor: Gilbert C. Sih
  • Patent number: 5704001
    Abstract: A novel and improved method and apparatus for quantizing the line spectral pair (LSP) frequencies in a speech compression system is disclosed. A novel and computationally efficient procedure for determining the set of quantization sensitivities for the LSP frequencies is disclosed, which results in a computationally efficient error measure for use in vector quantization of the LSP frequencies. A novel method of weighting the quantization error is disclosed, which accumulates the quantization error in each LSP frequency and weights that error by the sensitivity of that LSP frequency.
    Type: Grant
    Filed: August 4, 1994
    Date of Patent: December 30, 1997
    Assignee: QUALCOMM Incorporated
    Inventor: William R. Gardner
  • Patent number: 5703902
    Abstract: A method and apparatus of determining signal strength, regardless of the signal data rate, in a receiver receiving signals from a variable rate transmitter. The incoming signal is comprised of a series of frames. Each frame is comprised of a number of power control groups containing data. The number of the power control groups containing data within each frame is dependent on the unknown data rate. The position of the power control groups within the frame is a pseudorandom. The signal strength of an incoming signal of unknown data rate is determined based upon an active set of power control groups within a frame. The active set of power control groups contain data independent of the unknown data rate. This signal strength information may be used to indicate that the signal strength is sufficient to perform further signal processing.
    Type: Grant
    Filed: June 16, 1995
    Date of Patent: December 30, 1997
    Assignee: Qualcomm Incorporated
    Inventors: Noam Abraham Ziv, Roberto Padovani
  • Patent number: 5689311
    Abstract: A method and apparatus for reducing after images in motion video display. In the present invention, an intensity scaled image of a previous frame or set of frames is subtracted from the present frame before displaying the present frame. In the exemplary embodiment, the scaling factor is determined by measuring the intensity of the after image for the display device. In a preferred embodiment, the after image reduction system of the present invention takes into account the nonlinearities of the display device. That is the nonlinear relationship between the voltage applied to a display device and the intensity of the resulting display.
    Type: Grant
    Filed: September 15, 1995
    Date of Patent: November 18, 1997
    Assignee: QUALCOMM Incorporated
    Inventor: Chong U. Lee
  • Patent number: 5687229
    Abstract: A method for controlling echo canceling in an echo cancellation system using a state machine controller. A far-end speech signal transmitted through a communications channel may be passed through an echo channel to produce an echo signal. The echo signal is summed with a near-end speech signal and transmitted back to the far-end. An echo canceller rejects the echo signal by forming an estimate of the echo signal and subtracting the estimate from the sum of the near-end speech signal and the echo signal. The echo canceller includes a state machine which is configured into a predetermined state of a plurality of states depending on the presence near-end speech signal, far-end speech signal, or both near-end and far-end speech signals. Based on the predetermined state of the state machine, the controller in the state machine controls the update of coefficients of a plurality of adaptive filters.
    Type: Grant
    Filed: February 23, 1996
    Date of Patent: November 11, 1997
    Assignee: Qualcomm Incorporated
    Inventor: Gilbert C. Sih
  • Patent number: 5644596
    Abstract: A method and apparatus for performing subband adaptive filtering is proposed. A signal is prefiltered by a set of complementary filters to provide corresponding subbands of the input signal. The subbands of the signal are then provided to adaptive filters that filter the subbands separately. The individually filtered subbands are then summed. In an exemplary implementation an echo canceller is presented which employs the subband filtering method and apparatus.
    Type: Grant
    Filed: September 13, 1995
    Date of Patent: July 1, 1997
    Assignee: Qualcomm Incorporated
    Inventor: Gilbert C. Sih