Patents by Inventor Venugopal Balasubramonian

Venugopal Balasubramonian 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: 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
  • Patent number: 7039104
    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: December 17, 2002
    Date of Patent: May 2, 2006
    Assignee: Scintera Networks, Inc.
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Patent number: 7035330
    Abstract: A decision feedback equalizer with dynamic feedback control for use in an adaptive signal equalizer. Timing within the decision feedback loop is dynamically controlled to optimize recovery of the data signal by the output signal slicer. The dynamic timing is controlled by a signal formed as a combination of feedback and feedforward signals. The feedback signal is an error signal related to a difference between pre-slicer and post-slicer signals. The feedforward signal is formed by differentiating and delaying the incoming data signal.
    Type: Grant
    Filed: January 30, 2004
    Date of Patent: April 25, 2006
    Assignee: Scintera Networks, Inc.
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit M. Phanse, Jishnu Bhatacharjee, Debanjan Mukherjee, Venugopal Balasubramonian, Fabian Giroud, Edem Ibragimov
  • Patent number: 7016406
    Abstract: Tap coefficients for fractionally-spaced equalizers are updated iteratively using error statistics from an input bit stream and an output bit stream, such as from a forward error correction circuit. The process continues until the errors converge to a sufficiently small number. Knowledge of the error patterns are used apriori to adaptively change the tap coefficients in a feedforward filter.
    Type: Grant
    Filed: April 29, 2003
    Date of Patent: March 21, 2006
    Assignee: Scintera Networks
    Inventors: Abhijit Phanse, Abhijit G. Shanbhag, Qian Yu, Venugopal Balasubramonian, Jishnu Bhattacharjee, Prashant Choudhary, Debanjan Mukherjee, Fabian Giroud, Edem Ibragimov
  • 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
  • Patent number: 6940898
    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 8, 2002
    Date of Patent: September 6, 2005
    Assignee: Scintera Networks, Inc.
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Patent number: 6922440
    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: Grant
    Filed: December 17, 2002
    Date of Patent: July 26, 2005
    Assignee: Scintera Networks, Inc.
    Inventors: Qian Yu, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit G. Shanbhag, Edem Ibragimov
  • Publication number: 20040240539
    Abstract: A decision feedback equalizer with dynamic feedback control for use in an adaptive signal equalizer. Timing within the decision feedback loop is dynamically controlled to optimize recovery of the data signal by the output signal slicer.
    Type: Application
    Filed: January 30, 2004
    Publication date: December 2, 2004
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit M. Phanse, Jishnu Bhatacharjee, Debanjan Mukherjee, Venugopal Balasubramonian, Fabian Giroud
  • Publication number: 20040202258
    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: February 27, 2004
    Publication date: October 14, 2004
    Inventors: Qian Yu, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit G. Shanbhag, Edem Ibragimov, Fabian Giroud
  • Publication number: 20040114700
    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: December 17, 2002
    Publication date: June 17, 2004
    Inventors: Qian Yu, Venugopal Balasubramonian, Jishnu Bhattacharjee, Debanjan Mukherjee, Abhijit Phanse, Abhijit G. Shanbhag, Edem Ibragimov
  • Publication number: 20040091041
    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: December 17, 2002
    Publication date: May 13, 2004
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Publication number: 20040091036
    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: November 8, 2002
    Publication date: May 13, 2004
    Inventors: Venugopal Balasubramonian, Jishnu Bhattacharjee, Edem Ibragimov, Debanjan Mukherjee, Abhijit Phanse, Abhijit G. Shanbhag, Qian Yu
  • Publication number: 20040091040
    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 8, 2002
    Publication date: May 13, 2004
    Inventors: Abhijit G. Shanbhag, Qian Yu, Abhijit Phanse, Jishnu Bhattacharjee, Debanjan Mukherjee, Fabian Giroud, Venugopal Balasubramonian
  • Publication number: 20040091037
    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: December 17, 2002
    Publication date: May 13, 2004
    Inventors: Venugopal Balasubramonian, Jishnu Bhattacharjee, Edem Ibragimov, Debanjan Mukherjee, Abhijit Phanse, Abhijit G. Shanbhag, Qian Yu
  • Patent number: 6694496
    Abstract: An architecture and method for flexible preamble processing is disclosed herein. The preamble processing engine detects a code sequence in input, where the code sequence is a sum of a first code sequence and a second code sequence The preamble processing engine includes a data input line, a code input line, a despreader, and a plurality of memory registers. The code input selectively receives the first code sequence or the second code sequence, the first code sequence having a period longer than a period for the second code sequence. The despreader is coupled to the data input line and the code input line. The despreader producing a despread result between the first code sequence and the input data. Lastly, the plurality of memory registers, which are coupled to the despreader, each stores only a portion of the despread results.
    Type: Grant
    Filed: August 3, 2001
    Date of Patent: February 17, 2004
    Assignee: Morphics Technology, Inc.
    Inventors: Gregory R. Goslin, Venugopal Balasubramonian
  • Publication number: 20020065116
    Abstract: A wireless communication system hosts a plurality of processes in accordance with a communication protocol. The system includes application specific instruction set processors (ASISPs) that provided computation support for the process. Each ASISP is capable of executing a subset of the functions of a communication protocol. A scheduler is used to schedule the ASISPs in a time-sliced algorithm so that each ASISP supports several processes. In this architecture, the ASISP actively performs computations for one of the supported processes (active process) at any given time. The state information of each process supported by a particular ASISP is stored in a memory bank that is uniquely associated with the ASISP. When a scheduler instructs an ASISP to change which process is the active process, the state information for the inactivated process is stored in the memory bank and the state information for the newly activated process is retrieved from the memory bank.
    Type: Application
    Filed: July 24, 2001
    Publication date: May 30, 2002
    Inventors: Song Chen, Paul L. Chou, Christopher C. Woodthorpe, Venugopal Balasubramonian, Keith Rieken
  • Publication number: 20020016949
    Abstract: An architecture and method for flexible preamble processing is disclosed herein. The preamble processing engine detects a code sequence in input, where the code sequence is a sum of a first code sequence and a second code sequence The preamble processing engine includes a data input line, a code input line, a despreader, and a plurality of memory registers. The code input selectively receives the first code sequence or the second code sequence, the first code sequence having a period longer than a period for the second code sequence. The despreader is coupled to the data input line and the code input line. The despreader producing a despread result between the first code sequence and the input data. Lastly, the plurality of memory registers, which are coupled to the despreader, each stores only a portion of the despread results.
    Type: Application
    Filed: August 3, 2001
    Publication date: February 7, 2002
    Inventors: Gregory R. Goslin, Venugopal Balasubramonian