Patents by Inventor Abhijit Shanbhag

Abhijit Shanbhag 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: 9093959
    Abstract: A mixed-signal adaptive integrated circuit may comprise a primary function circuit, a digitally controlled analog sub-system cooperatively connected with the primary function circuit, and an on-chip signal analyzer. The on-chip signal analyzer may be arranged to analyze RF signals. The signal analyzer may comprise at least one multiplexor for selecting selected RF signals for comparison and analysis, and may comprise a digital signal processor (DSP) for analyzing the selected RF signals and adjusting at least one operational parameter of the digital controlled analog sub-system responsive to the analysis.
    Type: Grant
    Filed: September 9, 2013
    Date of Patent: July 28, 2015
    Assignee: SCINTERA NETWORKS LLC
    Inventors: Qian Yu, Abhijit Shanbhag, Yan Wang
  • Publication number: 20140009229
    Abstract: A mixed-signal adaptive integrated circuit may comprise a primary function circuit, a digitally controlled analog sub-system cooperatively connected with the primary function circuit, and an on-chip signal analyzer. The on-chip signal analyzer may be arranged to analyze RF signals. The signal analyzer may comprise at least one multiplexor for selecting selected RF signals for comparison and analysis, and may comprise a digital signal processor (DSP) for analyzing the selected RF signals and adjusting at least one operational parameter of the digital controlled analog sub-system responsive to the analysis.
    Type: Application
    Filed: September 9, 2013
    Publication date: January 9, 2014
    Applicant: Scintera Networks, Inc
    Inventors: Qian Yu, Abhijit Shanbhag, Yan Wang
  • Patent number: 8229027
    Abstract: Pre-distortion and memory compensation apparatuses and methods for a non-linear component are provided. The apparatus comprises an adaptive block for generating a plurality of correlation coefficients, which are used to weight a plurality of synthesis work functions to pre-distort a given signal. The adaptive block can be driven by an error signal generated from a feedback signal from the non-linear component output signal and a delayed version of the input signal. The apparatus is capable of being operated directly at radio frequency. Also provided are apparatuses and methods for generation of quadrature signals, transconductance amplification employing negative resistance, variable-gain amplification, and envelope detection.
    Type: Grant
    Filed: October 21, 2010
    Date of Patent: July 24, 2012
    Assignee: Scintera Networks, Inc.
    Inventors: Arvind Keerthi, Madabusi Govindarajan, P. Vijay Kumar, John Choma, Abhijit Shanbhag
  • Publication number: 20110032033
    Abstract: Pre-distortion and memory compensation apparatuses and methods for a non-linear component are provided. The apparatus comprises an adaptive block for generating a plurality of correlation coefficients, which are used to weight a plurality of synthesis work functions to pre-distort a given signal. The adaptive block can be driven by an error signal generated from a feedback signal from the non-linear component output signal and a delayed version of the input signal. The apparatus is capable of being operated directly at radio frequency. Also provided are apparatuses and methods for generation of quadrature signals, transconductance amplification employing negative resistance, variable-gain amplification, and envelope detection.
    Type: Application
    Filed: October 21, 2010
    Publication date: February 10, 2011
    Applicant: SCINTERA NETWORKS, INC.
    Inventors: Arvind Keerthi, Madabusi Govindarajan, P. Vijay Kumar, John Choma, Abhijit Shanbhag
  • Patent number: 7844014
    Abstract: Pre-distortion apparatuses and methods for a non-linear component are provided. The apparatus comprises an adaptive block for generating a plurality of correlation coefficients, which are used to weight a plurality of synthesis work functions to pre-distort a given signal. The adaptive block can be driven by an error signal generated from a feedback signal from the non-linear component output signal and a delayed version of the input signal. The apparatus is capable of being operated directly at radio frequency. Also provided are apparatuses and methods for generation of quadrature signals, transconductance amplification employing negative resistance, variable-gain amplification, and envelope detection.
    Type: Grant
    Filed: July 7, 2006
    Date of Patent: November 30, 2010
    Assignee: Scintera Networks, Inc.
    Inventors: Arvind Keerthi, Madabusi Govindarajan, P. Vijay Kumar, John Choma, Abhijit Shanbhag
  • Patent number: 7421021
    Abstract: An adaptive signal equalizer with a feedforward filter in which the feedback error signal and corresponding incoming data signal are dynamically aligned in time using signal interpolation, and further, to control the precursor/postcursor filter taps configuration, thereby producing more adaptive filter tap coefficient signals for significantly improved and robust signal equalization.
    Type: Grant
    Filed: June 7, 2007
    Date of Patent: September 2, 2008
    Assignee: Inphi Corporation
    Inventors: Venugopal Balasubramonian, Jishnu Bhattacharjee, Edem Ibragimov, Debanjan Mukherjee, Abhijit Phanse, Abhijit Shanbhag, Qian Yu
  • Patent number: 7421022
    Abstract: A continuous time electronic dispersion compensation architecture using feed forward equalization and a non-linear decision feedback equalization forms an output signal by a linear combination of successively delayed versions of the input signal and the sliced output signal weighted by appropriate coefficients. A selected number of taps in the mixer used to generate a corresponding number of coefficients for use in the feed forward equalizer are held to a selected voltage to ensure that the coefficients associated with these two taps do not drift. This causes the other coefficients to converge to a unique minimum square error value. In one embodiment the selected voltage is the maximum system voltage.
    Type: Grant
    Filed: April 27, 2005
    Date of Patent: September 2, 2008
    Assignee: Inphi Corporation
    Inventors: Prashant Choudhary, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit Shanbhag, Qian Yu
  • Publication number: 20080008263
    Abstract: Pre-distortion apparatuses and methods for a non-linear component are provided. The apparatus comprises an adaptive block for generating a plurality of correlation coefficients, which are used to weight a plurality of synthesis work functions to pre-distort a given signal. The adaptive block can be driven by an error signal generated from a feedback signal from the non-linear component output signal and a delayed version of the input signal. The apparatus is capable of being operated directly at radio frequency. Also provided are apparatuses and methods for generation of quadrature signals, transconductance amplification employing negative resistance, variable-gain amplification, and envelope detection.
    Type: Application
    Filed: July 7, 2006
    Publication date: January 10, 2008
    Inventors: Arvind Keerthi, Madabusi Govindarajan, P. Vijay Kumar, John Choma, Abhijit Shanbhag
  • Publication number: 20070230557
    Abstract: An adaptive signal equalizer with a feedforward filter in which the feedback error signal and corresponding incoming data signal are dynamically aligned in time using signal interpolation, and further, to control the precursor/postcursor filter taps configuration, thereby producing more adaptive filter tap coefficient signals for significantly improved and robust signal equalization.
    Type: Application
    Filed: June 7, 2007
    Publication date: October 4, 2007
    Applicant: Scintera Networks, Inc.
    Inventors: Venugopal Balasubramonian, Jishnu Bhattacharjee, Edem Ibragimov, Debanjan Mukherjee, Abhijit Phanse, Abhijit Shanbhag, Qian Yu
  • Patent number: 7203233
    Abstract: An adaptive coefficient signal generator for use in an adaptive signal equalizer with fractionally-spaced feedback. The signals representing the feedback tap coefficients are generated in conjunction with a timing interpolation parameter such that the fractionally-spaced feedback circuitry dynamically emulates symbol-spaced feedback circuitry.
    Type: Grant
    Filed: November 21, 2005
    Date of Patent: April 10, 2007
    Assignee: Scintera Networks, Inc.
    Inventors: Abhijit Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Publication number: 20070064845
    Abstract: A compensation circuit and method for reducing ISI products within an electrical data signal corresponding to a detected data signal received via a signal transmission medium introduces distinct compensation effects for individual ISI products within the electrical data signal. Distinct data signal components within the detected data signal and corresponding to such ISI products can be selectively and individually compensated, thereby producing a compensated data signal in which each selected one of such individual data signal components is substantially removed. Individual data signal components or selected combinations of data signal components can be compensated as desired.
    Type: Application
    Filed: October 26, 2006
    Publication date: March 22, 2007
    Applicant: SCINTERA NETWORKS, INC.
    Inventors: Abhijit Phanse, Abhijit Shanbhag
  • Publication number: 20060262805
    Abstract: A method is taught for transmitting message signals in a communication system having a new call entering the communication system and Walsh codes that can be active and inactive. The method includes dividing the Walsh codes into bins and determining the number of active Walsh codes in the bins. Selecting a Walsh code in accordance with the Walsh code number determination and assigning the selected Walsh code to the new call are set forth.
    Type: Application
    Filed: April 3, 2006
    Publication date: November 23, 2006
    Inventor: Abhijit Shanbhag
  • Publication number: 20060245486
    Abstract: A continuous time electronic dispersion compensation architecture using feed forward equalization and a non-linear decision feedback equalization forms an output signal by a linear combination of successively delayed versions of the input signal and the sliced output signal weighted by appropriate coefficients. A selected number of taps in the mixer used to generate a corresponding number of coefficients for use in the feed forward equalizer are held to a selected voltage to ensure that the coefficients associated with these two taps do not drift. This causes the other coefficients to converge to a unique minimum square error value. In one embodiment the selected voltage is the maximum system voltage.
    Type: Application
    Filed: April 27, 2005
    Publication date: November 2, 2006
    Inventors: Prashant Choudhary, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit Shanbhag, Qian Yu
  • Publication number: 20060104342
    Abstract: An adaptive coefficient signal generator for use in an adaptive signal equalizer with fractionally-spaced feedback. The signals representing the feedback tap coefficients are generated in conjunction with a timing interpolation parameter such that the fractionally-spaced feedback circuitry dynamically emulates symbol-spaced feedback circuitry.
    Type: Application
    Filed: November 21, 2005
    Publication date: May 18, 2006
    Applicant: Scintera Networks, Inc.
    Inventors: Abhijit Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Publication number: 20060082413
    Abstract: Systems and methods are disclosed to adaptively pre-distort a signal prior to being used by a non-linear circuit, such as a higher power amplifier (at transmit) or a low noise amplifier (at receive). The signal is compared with a feedback signal from the non-linear circuit and a metric is calculated and minimized. The input signal is adaptively changed, such as by varying tap coefficients, until the metric is sufficiently minimized, resulting in a pre-distorted signal that is substantially linear upon passing through the non-linear circuit.
    Type: Application
    Filed: October 28, 2005
    Publication date: April 20, 2006
    Inventor: Abhijit Shanbhag
  • Publication number: 20050271138
    Abstract: An apparatus and method for adaptively introducing a compensating signal latency related to a signal latency of a data symbol decision circuit. Adaptive timing control circuitry, including an interpolating mixer implemented as a tapped delay line with correlated tap coefficients, introduces a latency adaptively and substantially matching the latency of the data decision circuit for use within an adaptive equalizer, thereby minimizing the mean-squared error of such decision circuit. This adaptive latency is used in generating the feedback error signal which, in turn, can be used by the feedforward equalizer for dynamically adjusting its adaptive filter tap coefficients.
    Type: Application
    Filed: July 21, 2005
    Publication date: December 8, 2005
    Applicant: Scintera Networks, Inc.
    Inventors: Qian Yu, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit Shanbhag, Edem Ibragimov, Fabian Giroud
  • Publication number: 20050099230
    Abstract: Systems and methods are disclosed to adaptively pre-distort a signal prior to being used by a non-linear circuit, such as a higher power amplifier (at transmit) or a low noise amplifier (at receive). The signal is compared with a feedback signal from the non-linear circuit and a metric is calculated and minimized. The input signal is adaptively changed, such as by varying tap coefficients, until the metric is sufficiently minimized, resulting in a pre-distorted signal that is substantially linear upon passing through the non-linear circuit.
    Type: Application
    Filed: November 7, 2003
    Publication date: May 12, 2005
    Inventor: Abhijit Shanbhag
  • Patent number: 6721349
    Abstract: The present invention is a novel and improved method and apparatus for reducing peak to average ratio in a system using auxiliary pilot channels as described in the TIA/EIA TR45.5 “cdma2000 ITU-R RTT Candidate Submission” to the ITU for consideration in the third generation wireless communication systems. A first method proposed in the present invention to deal with the above stated problem is to alter the phase of the auxiliary pilot channels to reduce to prevent the auxiliary pilot channels from adding constructively. A second method proposed in the present invention to deal with the above stated problem is to gate out the portion of the auxiliary pilot channels that add constructively. The present invention also proposes a novel demodulator design for receiving signals using the modified auxiliary pilot signals.
    Type: Grant
    Filed: January 28, 1999
    Date of Patent: April 13, 2004
    Assignee: Qualcomm Incorporated
    Inventors: Serge Willenegger, Jack M. Holtzman, Abhijit Shanbhag