Patents by Inventor Jeffrey S. Baird

Jeffrey S. Baird 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).

  • Publication number: 20190349132
    Abstract: A radio transmitter comprises transmitting circuitry and processing circuitry. The transmitting circuitry broadcasts a frequency modulation (FM) in-band on-channel (IBOC) radio signal, wherein the FM IBOC radio signal includes multiple subcarriers grouped into multiple frequency partitions. The processing circuitry is configured to receive input bits for transmitting; encode and puncture the input bits using forward error correction (FEC) encoding; distribute encoded input bits between a main encoded component and a backup encoded component, wherein encoded bits of the backup encoded component are delayed for a specified duration relative to encoded bits of the main encoded component; allocate the encoded input bits of the main and backup encoded components into frequency diverse sidebands of the FM IBOC radio signal; and modulate the encoded input bits for transmitting using the frequency diverse sidebands of the FM IBOC radio signal, wherein the modulation is a type of quadrature amplitude modulation (QAM).
    Type: Application
    Filed: May 18, 2018
    Publication date: November 14, 2019
    Inventors: Paul J. Peyla, Brian W. Kroeger, Jeffrey S. Baird
  • Publication number: 20170272143
    Abstract: A method for processing a digital audio broadcast signal in a radio receiver includes: receiving a digital audio broadcast signal; demodulating the digital audio broadcast signal to produce an analog audio stream and a digital audio stream; determining a digital signal quality value for the digital audio stream; blending an output of the radio receiver from the analog audio stream to the digital audio stream when the digital signal quality value exceeds an adaptive analog-to-digital threshold value; and blending the output of the radio receiver from the digital audio stream to the analog audio stream when the digital signal quality value falls below an adaptive digital-to-analog threshold value, wherein the adaptive digital-to-analog threshold value is lower than the adaptive analog-to-digital threshold value.
    Type: Application
    Filed: March 16, 2016
    Publication date: September 21, 2017
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Patent number: 9768853
    Abstract: A method for processing a digital audio broadcast signal in a radio receiver includes: receiving a digital audio broadcast signal; demodulating the digital audio broadcast signal to produce an analog audio stream and a digital audio stream; determining a digital signal quality value for the digital audio stream; blending an output of the radio receiver from the analog audio stream to the digital audio stream when the digital signal quality value exceeds an adaptive analog-to-digital threshold value; and blending the output of the radio receiver from the digital audio stream to the analog audio stream when the digital signal quality value falls below an adaptive digital-to-analog threshold value, wherein the adaptive digital-to-analog threshold value is lower than the adaptive analog-to-digital threshold value.
    Type: Grant
    Filed: March 16, 2016
    Date of Patent: September 19, 2017
    Assignee: Ibiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Patent number: 9037103
    Abstract: A method for processing a radio signal includes: receiving a signal on two antennas; demodulating the signal using first and second independent signal paths that are synchronized by symbol number; maximum ratio combining branch metrics from the two receiver paths; and using the combined branch metrics to produce an output, wherein the receiver paths include an arbitration scheme. A receiver that implements the method is also provided.
    Type: Grant
    Filed: June 5, 2014
    Date of Patent: May 19, 2015
    Assignee: iBiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Publication number: 20140342682
    Abstract: A method for processing a radio signal includes: receiving a signal on two antennas; demodulating the signal using first and second independent signal paths that are synchronized by symbol number; maximum ratio combining branch metrics from the two receiver paths; and using the combined branch metrics to produce an output, wherein the receiver paths include an arbitration scheme. A receiver that implements the method is also provided.
    Type: Application
    Filed: June 5, 2014
    Publication date: November 20, 2014
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Patent number: 8831546
    Abstract: A radio receiver includes a first signal path including a first tuner configured to receive a first signal from a first antenna, and a first demodulator configured to demodulate symbols from an output of the first tuner to produce first branch metrics derived from the demodulated symbols; a second signal path including a second tuner configured to receive a second signal from a second antenna, and a second demodulator configured to demodulate symbols from an output of the second tuner to produce second branch metrics derived from the demodulated symbols; a combiner for maximum ratio combining the first branch metrics and the second branch metrics; and processing circuitry to process the combined first and second branch metrics to produce an output signal.
    Type: Grant
    Filed: June 28, 2012
    Date of Patent: September 9, 2014
    Assignee: iBiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Publication number: 20130115903
    Abstract: A radio receiver includes a first signal path including a first tuner configured to receive a first signal from a first antenna, and a first demodulator configured to demodulate symbols from an output of the first tuner to produce first branch metrics derived from the demodulated symbols; a second signal path including a second tuner configured to receive a second signal from a second antenna, and a second demodulator configured to demodulate symbols from an output of the second tuner to produce second branch metrics derived from the demodulated symbols; a combiner for maximum ratio combining the first branch metrics and the second branch metrics; and processing circuitry to process the combined first and second branch metrics to produce an output signal.
    Type: Application
    Filed: June 28, 2012
    Publication date: May 9, 2013
    Applicant: iBiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Patent number: 7724850
    Abstract: A method is provided for coherently tracking a radio signal including a plurality of digitally modulated reference subcarriers. The method comprises the steps of receiving symbols transmitted on the reference subcarriers, combining the reference subcarrier symbols with a known reference sequence conjugate to produce a plurality of samples, median filtering the samples to produce filtered samples, and smoothing the samples for each of the reference subcarriers over the plurality of reference subcarriers to produce a coherent reference signal estimate for each of the subcarriers. A receiver for coherently tracking a radio signal including at least one digitally modulated reference carrier is also provided.
    Type: Grant
    Filed: June 23, 2004
    Date of Patent: May 25, 2010
    Assignee: iBiquity Digital Corporation
    Inventors: Brian W. Kroeger, Paul J. Peyla, Jeffrey S. Baird
  • Patent number: 6982948
    Abstract: A transmitter for transmitting data in a digital audio broadcasting system includes a signal generator for providing a plurality of orthogonal frequency division multiplexed sub-carriers, with the sub-carriers including data sub-carriers and reference sub-carriers, and a modulator for modulating the data sub-carriers with a digital signal representative of information to be transmitted. The reference sub-carriers are modulated with a sequence of timing bits, wherein the sequence of timing bits includes an unambiguous block synchronization word, and the number of bits comprising the block synchronization word is less than one half of the number of bits in said timing sequence. The orthogonal frequency division multiplexed sub-carriers are transmitted to receivers that differentially detect the block synchronization word and use the block synchronization word to coherently detect the digital signal representative of information to be transmitted are also included.
    Type: Grant
    Filed: January 15, 2003
    Date of Patent: January 3, 2006
    Assignee: iBiquity Digital Corporation
    Inventors: Brian William Kroeger, Jeffrey S. Baird
  • Patent number: 6671340
    Abstract: This invention provides a method for reducing radio frequency interference in an FM in-band on-channel digital audio broadcasting receiver. The method comprises the steps of receiving a composite signal including a signal of interest and an interfering signal, demodulating the composite signal to produce a first demodulated signal, computing a first binary soft decision from the first demodulated signal, processing the composite signal to produce a processed signal, demodulating the processed signal to produce a second demodulated signal, computing a second binary soft decisions from the second demodulated signal, and combining the first and second binary soft decisions to produce an output signal. Radio receivers that utilize the above method are also included.
    Type: Grant
    Filed: June 15, 2000
    Date of Patent: December 30, 2003
    Assignee: iBiquity Digital Corporation
    Inventors: Brian William Kroeger, Jeffrey S. Baird
  • Publication number: 20030137928
    Abstract: A transmitter for transmitting data in a digital audio broadcasting system includes a signal generator for providing a plurality of orthogonal frequency division multiplexed sub-carriers, with the sub-carriers including data sub-carriers and reference sub-carriers, and a modulator for modulating the data sub-carriers with a digital signal representative of information to be transmitted. The reference sub-carriers are modulated with a sequence of timing bits, wherein the sequence of timing bits includes an unambiguous block synchronization word, and the number of bits comprising the block synchronization word is less than one half of the number of bits in said timing sequence. The orthogonal frequency division multiplexed sub-carriers are transmitted to receivers that differentially detect the block synchronization word and use the block synchronization word to coherently detect the digital signal representative of information to be transmitted are also included.
    Type: Application
    Filed: January 15, 2003
    Publication date: July 24, 2003
    Inventors: Brian William Kroeger, Jeffrey S. Baird
  • Patent number: 6549544
    Abstract: A method for transmission of data in a digital audio broadcasting system includes the steps of providing a plurality of orthogonal frequency division multiplexed sub-carriers, with the sub-carriers including data sub-carriers and reference sub-carriers, and modulating the data sub-carriers with a digital signal representative of information to be transmitted. The reference sub-carriers are modulated with a sequence of timing bits, wherein the sequence of timing bits includes an unambiguous block synchronization word, and the number of bits comprising the block synchronization word is less than one half of the number of bits in said timing sequence. Then the orthogonal frequency division multiplexed sub-carriers are transmitted. Receivers that differentially detect the block synchronization word and use the block synchronization word to coherently detect the digital signal representative of information to be transmitted are also included.
    Type: Grant
    Filed: November 10, 1999
    Date of Patent: April 15, 2003
    Assignee: Ibiquity Digital Corporation
    Inventors: Brian William Kroeger, Jeffrey S. Baird
  • Patent number: 5828705
    Abstract: The carrier tracking loop technique and apparatus provides smooth, accurate frequency tracking, fast reacquisition and doppler tracking over a wide dynamic range. The loop parameters of the carrier tracking loop are varied as a function of mode, i.e. flywheel, tracking or reacquisition modes. The various modes of operation are automatically detected and loop operation is enhanced by non-linear techniques. The enhancements include fourth power sample normalization to improve performance over a large dynamic range and to ease fixed point scaling. A slope limiter is included which aids in coherent detection by reducing phase noise introduced by the carrier tracking loop. Also, a predifferentiation filter further aids in coherent detection by reducing phase noise.
    Type: Grant
    Filed: February 1, 1996
    Date of Patent: October 27, 1998
    Inventors: Brian W. Kroeger, Jeffrey S. Baird
  • Patent number: 5768323
    Abstract: A method and apparatus for synchronizing symbol timing for a QPSK demodulator. A matched filter pair outputs respective "early-punctual-late" signals. The early and late signals are input to a symbol synchronizing estimator that produces an interpolation control signal used by the filters to synchronize the symbol timing to the sample timing. The punctual signal is output as an information bearing signal representing the received inphase and quadrature signals. The matched filters are interpolating matched filters. The symbol synchronizing estimator normalizes the early and late signals in a manner that allow the demodulator to "flywheel" over signals having a low signal to noise ratio below a predetermined threshold.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: June 16, 1998
    Assignee: Westinghouse Electric Corporation
    Inventors: Brian W. Kroeger, Joseph B. Bronder, Tod A. Oblak, Jeffrey S. Baird
  • Patent number: 5684835
    Abstract: A locally coherent Quadrature Phase Shift Keying (QPSK) detector that uses a normalized fourth power weighting technique to generate an ambiguous local phase reference of a current symbol. A phase adjusted previous symbol reference is used to resolve the ambiguity using differentially coded data and yield current soft symbol information.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: November 4, 1997
    Assignee: Westinghouse Electric Corporation
    Inventors: Brian W. Kroeger, Joseph B. Bronder, Jeffrey S. Baird
  • Patent number: 5598441
    Abstract: A method and apparatus for estimating a frequency of a received carrier wave in a Quadrature Phase Shift Keying (QPSK) system. The invention uses a combination of an FFT, DFT bins, and three point interpolation to estimate a frequency of the carrier wave. The system is robust and compensates for multipath fading and other types of signal degradation.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: January 28, 1997
    Assignee: Westinghouse Electric Corp.
    Inventors: Brian W. Kroeger, Joseph B. Bronder, Jeffrey S. Baird
  • Patent number: 5579345
    Abstract: A carrier tracking loop that uses a frequency locked loop (FLL) and incorporates synchronized matched filters to minimize complexity of the system. The synchronized matched filters eliminate out-of-band interference while minimizing computation. The carrier tracking loop has an improved error signal generation to extend a frequency range and by employing error signal normalization, which extends the dynamic range of the amplitude of the input signal and allows the frequency to flywheel when signal fading occurs.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: November 26, 1996
    Assignee: Westinghouse Electric Corporation
    Inventors: Brian W. Kroeger, Jeffrey S. Baird, Joseph B. Bronder
  • Patent number: 5566214
    Abstract: A QPSK demodulator symbol tracking loop including automatic noise normalization and reacquisition control enables improved symbol tracking and acquisition during fading or intermittent channel conditions. A noise variance estimate is determined and the symbol tracking loop flywheels when the signal level dips below a flywheel threshold relative to the noise variance estimate during fading or intermittent channel conditions. Determination in advance of an absolute power level of the thermal noise floor of analog front end components is dispensed with and precise control of the gain and noise level of the analog front end components is not needed, thus simplifying design. A reacquisition mode is declared upon determination of an abrupt increase in signal level indicative of emergence from a fading condition or upon detection of an excessive symbol tracking error signal. During the reacquisition mode, the loop gain of the symbol tracking loop is temporarily increased to improve reacquisition time.
    Type: Grant
    Filed: June 19, 1995
    Date of Patent: October 15, 1996
    Assignee: Westinghouse Electric Company
    Inventors: Brian W. Kroeger, Jeffrey S. Baird
  • Patent number: 5517535
    Abstract: A numerically controlled oscillator that outputs a complex exponential value (sine and cosine). The numerically controlled oscillator inputs a scalar phase increment and uses the scalar phase increment to approximate a complex exponential phasor increment. A complex multiplier multiplies the exponential increment by an exponential value previously output from the oscillator to yield a multiplication result. A recursive amplitude normalizer, connected to the complex multiplier, normalizes the multiplication result to yield the complex exponential value.
    Type: Grant
    Filed: October 13, 1994
    Date of Patent: May 14, 1996
    Assignee: Westinghouse Electric Corp.
    Inventors: Brian W. Kroeger, Jeffrey S. Baird