Patents by Inventor Narasimhan Venkatesh

Narasimhan Venkatesh 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: 7412000
    Abstract: A maximum likelihood CCK detector has a first subtractor which subtracts the contents of a pre-equalize register from a current symbol, and the output of this subtractor is coupled to a simple Fast Walsh Transform (FWT) with an iteration variable k. The output of the FWT is coupled to a second subtractor for subtracting a plurality of ICI corrections for all possible current symbols computed from the post-FWT domain value of the current CCK symbol and stored in post equalization registers. A post equalization register contains values computed from feedback filter coefficients determined during a packet preamble, where the feedback filter coefficients are provided to a reduced complexity post equalization value generator which populates the post equalization register using an iteration variable i.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: August 12, 2008
    Assignee: RedPine Signals, Inc.
    Inventors: Sankabathula Dharani Naga Sailaja, Parthasarathy Murali, Narasimhan Venkatesh
  • Patent number: 7386074
    Abstract: An RF receiver which produces quadrature digitized outputs and has a gain control is coupled to a digital gain controller which converts the quadrature digitized outputs into an rms voltage, and iterates over a finite number of steps to quickly control the gain to a level sufficient to achieve subsequent digital signal processing without limitations caused by insufficient dynamic range or nonlinear saturation effects caused by insufficient signal or excessive signal at the A/D input, respectively.
    Type: Grant
    Filed: October 6, 2003
    Date of Patent: June 10, 2008
    Assignee: RedPine Signals, Inc.
    Inventors: Narasimhan Venkatesh, Satya Rao, Dharani Naga Sailaja Sankabathula, Partha Sarathy Murali
  • Patent number: 7327700
    Abstract: A wireless signal processor for handling a plurality of wireless sessions comprises a plurality of baseband receivers, one for each session, each receiver producing a digital output, a multiplexer for multiplexing the plurality of digital outputs into a single data stream, a digital signal processor for converting the stream of multiplexed data into a media access controller format, and a media access controller for demultiplexing and framing the stream of data into a plurality of data buffers, one data buffer for each wireless session.
    Type: Grant
    Filed: May 30, 2003
    Date of Patent: February 5, 2008
    Assignee: Redpine Signals, Inc.
    Inventors: Narasimhan Venkatesh, Satya Rao, Heonchul Park
  • Patent number: 7298799
    Abstract: A decision processor for 802.11b codewords for 1 Mb and 2 Mb data rates includes a sliding correlator for the acquisition of correlation peaks. During a training interval, these correlation peaks are summed into a channel profile memory. The correlation peaks corresponding to a codeword are added into the channel profile memory, and correlation peaks corresponding to the inverse of this codeword are inverted and added into the channel profile memory during the training interval. After the training interval, a decision interval follows whereby correlation peaks are multiplied by the complex conjugate of the contents of the channel profile memory. The multiplication results are accumulated over a codeword window interval to produce a decision output.
    Type: Grant
    Filed: March 8, 2004
    Date of Patent: November 20, 2007
    Assignee: Redpine Signals, Inc.
    Inventors: Narasimhan Venkatesh, Sankabathula Dharani Naga Sailaja, Murali Partha Sarathy
  • Patent number: 7298772
    Abstract: A integrated system for generation of packet detection, symbol timing, and coarse frequency offset for an orthogonal frequency division multiplexed (OFDM) receiver having a stream of input symbols applied comprises a first multiplier performing a multiplication on a delayed and conjugated stream of input symbols multiplied by the input symbol stream. The output of the first multiplier is summed over a symbol length. A second multiplier has an output formed from multiplying the delayed symbol stream by its conjugate, thereby providing a signal strength term Pn. The output of the second multiplier is summed over two symbol periods, and multiplied by a known threshold to form a threshold value. When the magnitude of cn term rises above the known threshold, this generates a packet detect output, and when the magnitude of Cn terms thereafter falls below the known threshold, this generates a symbol timing output.
    Type: Grant
    Filed: September 3, 2004
    Date of Patent: November 20, 2007
    Assignee: Redpine Signals, Inc.
    Inventors: Ravikumar Neerudu, Narasimhan Venkatesh, Ponnamanda Venkata Chandra Sekhar
  • Patent number: 7296100
    Abstract: A memory controller for a wireless communication system comprises a packet buffer write system and a packet buffer read system. The packet buffer write system places packets including packet header and packet data into a packet buffer. The packet buffer read system removes packets including a packet header and packet data from a packet buffer. The packet buffer is arranged into a plurality of packet buffer memory slots, each slot comprising a descriptor status array location including an availability bit set to “used” or “free”, and a packet buffer memory location comprising a descriptor memory slot and a data segment memory slot. The descriptor memory slot includes header information for each packet, and the data segment memory slot includes packet data. The memory controller operates on one or more queues of data, and data is placed into a particular queue in packet memory determined by priority information derived from incoming packet header or packet data.
    Type: Grant
    Filed: October 6, 2003
    Date of Patent: November 13, 2007
    Assignee: Redpine Signals, Inc.
    Inventors: Narasimhan Venkatesh, Satya Rao
  • Patent number: 7218896
    Abstract: A baseband receiver having quadrature analog outputs and a plurality of analog control and status signals and a transmit modulator having analog quadrature inputs and a plurality of analog control and status signals are coupled to a transmit processor having a digital output and a plurality of digital control and status signals and to a receive processor having a digital input and a plurality of digital control and status signals by multiplexing analog to digital converters and digital to analog converters such that during a receive time the converters are used for a receive purpose and during a transmit time, the converters are used for a transmit purpose.
    Type: Grant
    Filed: December 21, 2003
    Date of Patent: May 15, 2007
    Assignee: Redpine Signals, Inc.
    Inventor: Narasimhan Venkatesh
  • Publication number: 20040240486
    Abstract: A wireless signal processor for handling a plurality of wireless sessions comprises a plurality of baseband receivers, one for each session, each receiver producing a digital output, a multiplexer for multiplexing the plurality of digital outputs into a single data stream, a digital signal processor for converting the stream of multiplexed data into a media access controller format, and a media access controller for demultiplexing and framing the stream of data into a plurality of data buffers, one data buffer for each wireless session.
    Type: Application
    Filed: May 30, 2003
    Publication date: December 2, 2004
    Inventors: Narasimhan Venkatesh, Satya Rao, Heonchul Park