Patents by Inventor Robindra B. Joshi

Robindra B. Joshi 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: 8537934
    Abstract: A method of compensating for carrier frequency and phase errors of a received multi-carrier modulated signal. The received multi-carrier signal including modulated carriers for transmitting known data and unmodulated carriers for error correction, comprising, time domain down converting the received multi-carrier signal to base-band to provide a down-converted signal, the down-converted signal including a plurality of modulated carriers for transmitting known data and unmodulated carriers for error correction. Sampling an unmodulated carrier of the down-converted signal to provide received data samples. Providing a reference signal derived from the unmodulated carrier of the down-converted signal. And, estimating phase errors from a phase difference between the ummodulated carrier and the reference signal derived from the unmodulated carrier of the down-converted signal to provide a plurality of received sample phase error estimates for each modulated carrier.
    Type: Grant
    Filed: January 12, 2006
    Date of Patent: September 17, 2013
    Assignee: Broadcom Corporation
    Inventors: Robindra B. Joshi, Jeffrey S. Putnam, Thuji S. Lin, Paul T. Yang
  • Patent number: 7035253
    Abstract: A communication unit (30) arranged to send transmit data includes a receiver (32) arranged to recover input data transmitted at a downstream transfer rate in response to a symbol clock (20) signal. A transmitter (40) is arranged to transmit the transmit data at an upstream transfer rate in response to an upstream transmit clock signal (TX_CLKA) that is coordinated with the symbol clock signal. The frequency or repetition rate of the upstream transmit clock signal is defined at least in part by a predetermined relationship between the downstream transfer rate and the upstream transfer rate, such as a ratio of the downstream transfer rate and the upstream transfer rate.
    Type: Grant
    Filed: January 28, 2002
    Date of Patent: April 25, 2006
    Assignee: Broadcom Corporation
    Inventors: Martin Kuhlmann, Robindra B. Joshi
  • Patent number: 7010062
    Abstract: A method of compensating for carrier frequency and phase errors of a received multi-carrier modulated signal. The received multi-carrier signal including modulated carriers for transmitting known data and unmodulated carriers for error correction, comprising, time domain down converting the received multi-carrier signal to base-band to provide a down-converted signal, the down-converted signal including a plurality of modulated carriers for transmitting known data and unmodulated carriers for error correction. Sampling an unmodulated carrier of the down-converted signal to provide received data samples. Providing a reference signal derived from the unmodulated carrier of the down-converted signal. And, estimating phase errors from a phase difference between the ummodulated carrier and the reference signal derived from the unmodulated carrier of the down-converted signal to provide a plurality of received sample phase error estimates for each modulated carrier.
    Type: Grant
    Filed: April 4, 2001
    Date of Patent: March 7, 2006
    Assignee: Broadcom Corporation
    Inventors: Robindra B. Joshi, Jeffrey S. Putnam, Thuji S. Lin, Paul T. Yang
  • Patent number: 6870429
    Abstract: Clock signals and digital data signals at a variable frequency are introduced to the input of a FIFO and are passed from the FIFO at a second (or intermediate) frequency controlled by a numerically controlled oscillator. To regulate the frequency of the signals from the numerically controlled oscillator, the phases of the clock signals at the variable frequency are compared in a phase detector with the phases of the signals from the numerically controlled oscillator to generate an error signal. The error signals and the signals at a fixed sampling frequency higher than the intermediate frequency regulate the frequency of the signals from the numerically controlled oscillator and thus the frequency of the digital data signals from the FIFO. The digital data signals from the FIFO are converted to a pair of signals at the second frequency.
    Type: Grant
    Filed: June 25, 2003
    Date of Patent: March 22, 2005
    Assignee: Broadcom Corporation
    Inventors: Robert A. Hawley, Robindra B. Joshi, Huan-Chang Liu
  • Publication number: 20030231067
    Abstract: Clock signals and digital data signals at a variable frequency are introduced to the input of a FIFO and are passed from the FIFO at a second (or intermediate) frequency controlled by a numerically controlled oscillator. To regulate the frequency of the signals from the numerically controlled oscillator, the phases of the clock signals at the variable frequency are compared in a phase detector with the phases of the signals from the numerically controlled oscillator to generate an error signal. The error signals and the signals at a fixed sampling frequency higher than the intermediate frequency regulate the frequency of the signals from the numerically controlled oscillator and thus the frequency of the digital data signals from the FIFO. The digital data signals from the FIFO are converted to a pair of signals at the second frequency.
    Type: Application
    Filed: June 25, 2003
    Publication date: December 18, 2003
    Applicant: Broadcom Corporation
    Inventors: Robert A. Hawley, Robindra B. Joshi, Huan-Chang Liu
  • Patent number: 6611568
    Abstract: Clock signals and digital data signals at a variable frequency are introduced to the input of a FIFO and are passed from the FIFO at a second (or intermediate) frequency controlled by a numerically controlled oscillator. To regulate the frequency of the signals from the numerically controlled oscillator, the phases of the clock signals at the variable frequency are compared in a phase detector with the phases of the signals from the numerically controlled oscillator to generate an error signal. The error signals and the signals at a fixed sampling frequency higher than the intermediate frequency regulate the frequency of the signals from the numerically controlled oscillator and thus the frequency of the digital data signals from the FIFO. The digital data signals from the FIFO are converted to a pair of signals at the second frequency.
    Type: Grant
    Filed: April 5, 2002
    Date of Patent: August 26, 2003
    Assignee: Broadcom Corporation
    Inventors: Robert A. Hawley, Robindra B. Joshi, Huan-Chang Liu
  • Publication number: 20030142771
    Abstract: A communication unit (30) arranged to send transmit data includes a receiver (32) arranged to recover input data transmitted at a downstream transfer rate in response to a symbol clock (20) signal. A transmitter (40) is arranged to transmit the transmit data at an upstream transfer rate in response to an upstream transmit clock signal (TX_CLKA) that is coordinated with the symbol clock signal. The frequency or repetition rate of the upstream transmit clock signal is defined at least in part by a predetermined relationship between the downstream transfer rate and the upstream transfer rate, such as a ratio of the downstream transfer rate and the upstream transfer rate.
    Type: Application
    Filed: January 28, 2002
    Publication date: July 31, 2003
    Inventors: Martin Kuhlmann, Robindra B. Joshi
  • Publication number: 20020118785
    Abstract: Clock signals and digital data signals at a variable frequency are introduced to the input of a FIFO and are passed from the FIFO at a second (or intermediate) frequency controlled by a numerically controlled oscillator. To regulate the frequency of the signals from the numerically controlled oscillator, the phases of the clock signals at the variable frequency are compared in a phase detector with the phases of the signals from the numerically controlled oscillator to generate an error signal. The error signals and the signals at a fixed sampling frequency higher than the intermediate frequency regulate the frequency of the signals from the numerically controlled oscillator and thus the frequency of the digital data signals from the FIFO. The digital data signals from the FIFO are converted to a pair of signals at the second frequency.
    Type: Application
    Filed: April 5, 2002
    Publication date: August 29, 2002
    Inventors: Robert A. Hawley, Robindra B. Joshi, Huan-Chang Liu
  • Patent number: 6421396
    Abstract: Clock signals and digital data signals at a variable frequency are introduced to the input of a FIFO and are passed from the FIFO at a second (or intermediate) frequency controlled by a numerically controlled oscillator. To regulate the frequency of the signals from the numerically controlled oscillator, the phases of the clock signals at the variable frequency are compared in a phase detector with the phases of the signals from the numerically controlled oscillator to generate an error signal. The error signals and the signals at a fixed sampling frequency higher than the intermediate frequency regulate the frequency of the signals from the numerically controlled oscillator and thus the frequency of the digital data signals from the FIFO. The digital data signals from the FIFO are converted to a pair of signals at the second frequency.
    Type: Grant
    Filed: April 16, 1997
    Date of Patent: July 16, 2002
    Assignee: Broadcom Corporation
    Inventors: Robert A. Hawley, Robindra B. Joshi, Huan-Chang Liu
  • Publication number: 20020064240
    Abstract: A method of compensating for carrier frequency and phase errors of a received multi-carrier modulated signal. The received multi-carrier signal including modulated carriers for transmitting known data and unmodulated carriers for error correction, comprising, time domain down converting the received multi-carrier signal to base-band to provide a down-converted signal, the down-converted signal including a plurality of modulated carriers for transmitting known data and unmodulated carriers for error correction. Sampling an unmodulated carrier of the down-converted signal to provide received data samples. Providing a reference signal derived from the unmodulated carrier of the down-converted signal. And, estimating phase errors from a phase difference between the ummodulated carrier and the reference signal derived from the unmodulated carrier of the down-converted signal to provide a plurality of received sample phase error estimates for each modulated carrier.
    Type: Application
    Filed: April 4, 2001
    Publication date: May 30, 2002
    Inventors: Robindra B. Joshi, Jeffrey S. Putnam, Thuji S. Lin, Paul T. Yang