Patents by Inventor James Jaffee

James Jaffee has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 8036622
    Abstract: Techniques for cancelling DC offset are described. A DC offset cancellation circuit in a receiver cancels DC offsets caused by leaked LO (local oscillator) signals from a LO signal generator. The receiver first calibrates itself by using the DC offset cancellation circuit during a transmit mode. During the calibration, the DC offset cancellation circuit stores the DC offset voltage signal caused by the leaked LO signals. During a receiving mode when the receiver is receiving a signal, the receiver subtracts the stored DC offset voltage signal from the received signal to cancel the DC offsets caused by leaked LO signals.
    Type: Grant
    Filed: January 28, 2006
    Date of Patent: October 11, 2011
    Assignee: QUALCOMM, Incorporated
    Inventors: Runhua (Ray) Sun, Christian Holenstein, James Jaffee
  • Patent number: 7548593
    Abstract: A phase modulator faithfully reproduces higher frequency modulation using an offset phase-locked loop (OPLL) without passing excessive noise through an increased bandwidth of the OPLL. A quadrature modulator modulates information from a baseband signal onto a passband IF signal and, after a limiter strips away amplitude variations, the OPLL reproduces the phase modulation on an RF signal. The OPLL introduces a group delay that does not vary linearly with the modulation frequency and that consequently causes distortion when uncompensated. A baseband filter filters the amplitude of the baseband signal and introduces a complementary group delay that compensates for the OPLL group delay and results in a combined group delay of the baseband filter, quadrature modulator, limiter and OPLL that remains substantially constant as modulation frequency varies. Compensating for the OPLL group delay reduces distortion and the spectral energy at offset frequencies from the carrier frequency of the RF signal.
    Type: Grant
    Filed: September 15, 2005
    Date of Patent: June 16, 2009
    Assignee: QUALCOMM Incorporated
    Inventors: Puay Hoe Andrew See, Gary John Ballantyne, James Jaffee, Gurkanwal Kamal Sahota
  • Patent number: 7415088
    Abstract: Techniques for processing incoming signals conforming to a plurality of standards or communication formats with a single baseband receive section are disclosed. In one aspect, a plurality of analog processing components are adjusted in response to a format select signal, set according to one of a plurality of supported formats or standards. In another aspect, the operating mode of an A/D converter is tuned in response to the format select signal. In yet another aspect, the response characteristics of a jammer filter are tuned in response to the format select signal. In yet another aspect, the adjustment of the plurality of analog processing components is carried out by varying the frequency of a sample clock in response to the format select signal. Various other aspects are also presented. These aspects have the benefit of allowing a single baseband receive section to be deployed to process analog signals conforming to a plurality of communications standards or formats, in a power and area efficient manner.
    Type: Grant
    Filed: April 15, 2002
    Date of Patent: August 19, 2008
    Assignee: QUALCOMM Incorporated
    Inventors: Vincenzo Filip Andre Peluso, Seyfollah Bazarjani, Peter Jivan Shah, James Jaffee
  • Publication number: 20070072571
    Abstract: Techniques for cancelling DC offset are described. A DC offset cancellation circuit in a receiver cancels DC offsets caused by leaked LO (local oscillator) signals from a LO signal generator. The receiver first calibrates itself by using the DC offset cancellation circuit during a transmit mode. During the calibration, the DC offset cancellation circuit stores the DC offset voltage signal caused by the leaked LO signals. During a receiving mode when the receiver is receiving a signal, the receiver subtracts the stored DC offset voltage signal from the received signal to cancel the DC offsets caused by leaked LO signals.
    Type: Application
    Filed: January 28, 2006
    Publication date: March 29, 2007
    Inventors: Runhua Sun, Christian Holenstein, James Jaffee
  • Publication number: 20070058750
    Abstract: A phase modulator faithfully reproduces higher frequency modulation using an offset phase-locked loop (OPLL) without passing excessive noise through an increased bandwidth of the OPLL. A quadrature modulator modulates information from a baseband signal onto a passband IF signal and, after a limiter strips away amplitude variations, the OPLL reproduces the phase modulation on an RF signal. The OPLL introduces a group delay that does not vary linearly with the modulation frequency and that consequently causes distortion when uncompensated. A baseband filter filters the amplitude of the baseband signal and introduces a complementary group delay that compensates for the OPLL group delay and results in a combined group delay of the baseband filter, quadrature modulator, limiter and OPLL that remains substantially constant as modulation frequency varies. Compensating for the OPLL group delay reduces distortion and the spectral energy at offset frequencies from the carrier frequency of the RF signal.
    Type: Application
    Filed: September 15, 2005
    Publication date: March 15, 2007
    Inventors: Puay Hoe See, Gary Ballantyne, James Jaffee, Gurkanwal Sahota
  • Patent number: 7167686
    Abstract: A wireless transceiver includes a transmitter having a harmonic rejection mixer and an RF output phase-locked loop in a two step up-conversion architecture, and a direct conversion receiver. The transmitter includes a local oscillator for producing a signal at a multiple of an intermediate frequency, a quadrature modulator harmonic rejection mixer responsive to the signal at the multiple of the intermediate frequency for modulating in-phase and quadrature-phase base-band signals to produce an intermediate frequency signal, a filter responsive to the intermediate frequency signal for producing a filtered intermediate frequency signal, and an RF output offset phase-locked loop responsive to the filtered intermediate frequency signal and the signal at the multiple of the intermediate frequency for producing an RF transmission signal. The harmonic rejection mixer reduces filtering requirements to facilitate a high level of circuit integration.
    Type: Grant
    Filed: January 24, 2003
    Date of Patent: January 23, 2007
    Assignee: Qualcomm Incorporated
    Inventors: Puay-Hoe Andrew See, James Jaffee, Steven Mollenkopf, Sandor Szabo
  • Patent number: 7130599
    Abstract: In an exemplary application, an apparatus according to a disclosed embodiment receives a radio frequency signal and outputs an intermediate frequency signal. Rejection of image components in the intermediate frequency signal is obtained without the need to preprocess the radio frequency signal with an image reject filter. Such an apparatus may also exhibit an image rejection performance that is robust to frequency deviation of a local oscillator.
    Type: Grant
    Filed: March 2, 2001
    Date of Patent: October 31, 2006
    Assignee: Qualcomm Inc.
    Inventors: Charles J. Persico, James Jaffee, Steven C. Ciccarelli
  • Publication number: 20040005869
    Abstract: A wireless transceiver includes a transmitter having a harmonic rejection mixer and an RF output phase-locked loop in a two step up-conversion architecture, and a direct conversion receiver. The transmitter includes a local oscillator for producing a signal at a multiple of an intermediate frequency, a quadrature modulator harmonic rejection mixer responsive to the signal at the multiple of the intermediate frequency for modulating in-phase and quadrature-phase base-band signals to produce an intermediate frequency signal, a filter responsive to the intermediate frequency signal for producing a filtered intermediate frequency signal, and an RF output offset phase-locked loop responsive to the filtered intermediate frequency signal and the signal at the multiple of the intermediate frequency for producing an RF transmission signal. The harmonic rejection mixer reduces filtering requirements to facilitate a high level of circuit integration.
    Type: Application
    Filed: January 24, 2003
    Publication date: January 8, 2004
    Applicant: QUALCOMM Incorporaton
    Inventors: Puay-Hoe Andrew See, James Jaffee, Steven Mollenkopf, Sandor Szabo
  • Publication number: 20030050085
    Abstract: Techniques for processing incoming signals conforming to a plurality of standards or communication formats with a single baseband receive section are disclosed. In one aspect, a plurality of analog processing components are adjusted in response to a format select signal, set according to one of a plurality of supported formats or standards. In another aspect, the operating mode of an A/D converter is tuned in response to the format select signalIn yet another aspect, the response characteristics of a jammer filter are tuned in response to the format select signal. In yet another aspect, the adjustment of the plurality of analog processing components is carried out by varying the frequency of a sample clock in response to the format select signal. Various other aspects are also presented. These aspects have the benefit of allowing a single baseband receive section to be deployed to process analog signals conforming to a plurality of communications standards or formats, in a power and area efficient manner.
    Type: Application
    Filed: April 15, 2002
    Publication date: March 13, 2003
    Inventors: Vincenzo Filip Andre Peluso, Seyfollah Bazarjani, Peter Jivan Shah, James Jaffee
  • Publication number: 20020055337
    Abstract: In an exemplary application, an apparatus according to a disclosed embodiment receives a radio frequency signal and outputs an intermediate frequency signal. Rejection of image components in the intermediate frequency signal is obtained without the need to preprocess the radio frequency signal with an image reject filter. Such an apparatus may also exhibit an image rejection performance that is robust to frequency deviation of a local oscillator.
    Type: Application
    Filed: March 2, 2001
    Publication date: May 9, 2002
    Inventors: Charles J. Persico, James Jaffee, Steven C. Ciccarelli