Patents by Inventor Sachin Katti

Sachin Katti 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: 20190274144
    Abstract: A backscatter tag device includes, in part, a receiver configured to receive a packet conforming to a communication protocol defining a multitude of codewords, a codeword translator configured to translate at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol in response to a data the backscatter tag is invoked to transmit, and a transmitter configured to transmit the packet supplied by the codeword translator at a frequency different than the first frequency at which the packer is received. The communication protocol may optionally be the 802.11 g/n, ZigBee or the Bluetooth communication protocol.
    Type: Application
    Filed: October 25, 2017
    Publication date: September 5, 2019
    Applicant: The Board of Trustees of the Leland Standford Junior University
    Inventors: Pengyu ZHANG, Dinesh BHARADIA, Sachin KATTI
  • Patent number: 10338205
    Abstract: A backscatter tag communicate device includes, in part, a receiver configured to receive a WiFi packet conforming to a communication protocol defining a multitude of codewords, a mapper configured to map at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol, and a frequency shifter configured to shift a frequency of the second multitude of codewords such that the frequency shifted codewords are characterized by a single sideband spectrum. The communication protocol may be the 802.11b communication protocol. The mapper may optionally map the first subset of the multitude of codewords by changing phases of the first subset of the multitude of codewords.
    Type: Grant
    Filed: August 14, 2017
    Date of Patent: July 2, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Pengyu Zhang, Dinesh Bharadia, Kiran Joshi, Sachin Katti
  • Patent number: 10284356
    Abstract: A wireless communication device includes, in part, an analog interference cancellation circuit and a controller. The analog cancellation circuit includes a multitude of delay paths each including a delay element and a variable attenuator. The controller dynamically varies the attenuation level of each of the variable attenuators in accordance with the frequency response characteristic of that attenuator to remove a portion of a self-interference signal present in a signal received by the device. The device measures the frequency response characteristic of the communication channel, used in determining the attenuation levels, via one or more preamble symbols. A second portion of the self-interference signal is removed by the device using a multitude of samples of a transmitted signal and a multitude of samples of a signal to be transmitted.
    Type: Grant
    Filed: August 11, 2014
    Date of Patent: May 7, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Dinesh Bharadia, Sachin Katti, Emily McMilin, Mayank Jain, Jung Il Choi, Kannan Srinivasan
  • Patent number: 10243718
    Abstract: A system for processing signals includes an interference cancellation component that samples an RF transmit signal, transforms the sampled RF transmit signal into a self-interference cancellation signal, and combines the sampled RF transmit signal and self-interference cancellation signal to remove a first portion of interference from the RF receive signal, the combination forming a processed RF signal; and a filtering component that removes a second portion of interference from the processed signal by downconverting the processed RF signal to a processed baseband signal, sampling the processed baseband signal to create a processed digital signal, and filtering the processed digital signal to remove the second portion of interference.
    Type: Grant
    Filed: April 19, 2016
    Date of Patent: March 26, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hong, Sachin Katti, Jeff Mehlman
  • Patent number: 10243719
    Abstract: A MIMO wireless communication device includes, in part, a first transmit path adapted to transmit a first transmit signal from a first antenna, a second transmit path adapted to transmit a second transmit signal from a second antenna, a first receive path adapted to receive a first receive signal, an interference cancellation circuit and a controller. The cancellation circuit includes a cascaded filter structure each filter including a multitude of filter taps each including a variable element. The controller dynamically varies a value applied to each of the plurality of variable elements in accordance with frequency response characteristics of the variable element to remove a portion of a self-interference and/or cross-talk interference signal present in a signal received by the device.
    Type: Grant
    Filed: September 29, 2014
    Date of Patent: March 26, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Dinesh Bharadia, Sachin Katti
  • Patent number: 10230419
    Abstract: In one aspect there is provided a method. The method may include receiving a first analog radio frequency signal including a signal of interest and an interference signal caused by a second analog radio frequency signal transmitted in full duplex over a channel from which the first analog transmission is received; adjusting at least one of the first analog radio frequency signal and a portion of the second analog radio frequency signal to enable at least one of a reduction or an elimination of the interference signal in an output analog radio frequency signal; combining the first analog radio frequency signal and the portion of the second analog radio frequency signal to generate the output analog radio frequency signal characterized by at least the reduction or the elimination of the interference signal included in the output analog radio frequency signal; and providing the output analog radio frequency signal. Related apparatus, systems, methods, and articles are also described.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: March 12, 2019
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Dinesh Bharadia, Jung-Il Choi, Mayank Jain, Sachin Katti, Tae Min Kim, Philip Levis
  • Publication number: 20180212807
    Abstract: A backscatter tag communicate device includes, in part, a receiver configured to receive a WiFi packet conforming to a communication protocol defining a multitude of codewords, a mapper configured to map at least a first subset of the multitude of codewords disposed in the packet to a second multitude of codewords defined by the protocol, and a frequency shifter configured to shift a frequency of the second multitude of codewords such that the frequency shifted codewords are characterized by a single sideband spectrum. The communication protocol may be the 802.11b communication protocol. The mapper may optionally map the first subset of the multitude of codewords by changing phases of the first subset of the multitude of codewords.
    Type: Application
    Filed: August 14, 2017
    Publication date: July 26, 2018
    Inventors: Pengyu ZHANG, Dinesh BHARADIA, Kiran JOSHI, Sachin KATTI
  • Patent number: 9887728
    Abstract: In one aspect there is provided a method. The method may include receiving a first analog radio frequency signal including a signal of interest and an interference signal caused by a second analog radio frequency signal transmitted in full duplex over a channel from which the first analog transmission is received; combining the first analog radio frequency signal and a portion of the second analog radio frequency signal to generate an output analog radio frequency signal characterized by at least a reduction or an elimination of the interference signal included in the output analog radio frequency signal; and providing the output analog radio frequency signal. Related apparatus, systems, methods, and articles are also described.
    Type: Grant
    Filed: November 9, 2011
    Date of Patent: February 6, 2018
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Mayank Jain, Jung Il Choi, Kannan Srinivasan, Philip Levis, Sachin Katti, Siddharth Seth
  • Publication number: 20170187513
    Abstract: A wireless communication device includes, in part, an analog interference cancellation circuit and a controller. The analog cancellation circuit includes a multitude of delay paths each including a delay element and a variable attenuator. The controller dynamically varies the attenuation level of each of the variable attenuators in accordance with the frequency response characteristic of that attenuator to remove a portion of a self-interference signal present in a signal received by the device. The device measures the frequency response characteristic of the communication channel, used in determining the attenuation levels, via one or more preamble symbols. A second portion of the self-interference signal is removed by the device using a multitude of samples of a transmitted signal and a multitude of samples of a signal to be transmitted.
    Type: Application
    Filed: August 11, 2014
    Publication date: June 29, 2017
    Inventors: Dinesh BHARADIA, Sachin KATTI, Emily McMILIN
  • Publication number: 20170090026
    Abstract: Techniques for a motion tracing device using radio frequency signals are presented. The motion tracing device utilizes radio frequency signals, such as WiFi to identify moving objects and trace their motion. Methods and apparatus are defined that can measure multiple WiFi backscatter signals and identify the backscatter signals that correspond to moving objects. In addition, motion of a plurality of moving objects can be detected and traced for a predefined duration of time.
    Type: Application
    Filed: May 4, 2015
    Publication date: March 30, 2017
    Inventors: Kiran Joshi, Dinesh Bharadia, Sachin Katti, Manikanta Kotaru
  • Patent number: 9490963
    Abstract: A circuit that cancels a self-interference signal includes, in part, a pair of signal paths that are substantially in phase, each of which paths includes a passive coupler, a delay element and a variable attenuator. The circuit further includes, in part, a first group of P signal paths each of which is substantially in phase with the pair of paths, a second group of M signal paths each of which is substantially out-of-phase relative to the pair of signal paths, and at least a pair of feedback paths. Each of the P and M signal paths, as well as the feedback paths includes a delay element and a variable attenuator. Optionally, each of the M signal paths is optionally 180° out-of-phase relative to the pair of signal paths.
    Type: Grant
    Filed: February 4, 2014
    Date of Patent: November 8, 2016
    Assignee: Kumu Networks, Inc.
    Inventors: Jung-il Choi, Steven Hong, Mayank Jain, Sachin Katti, Philip Levis, Jeff Mehlman
  • Publication number: 20160266245
    Abstract: Techniques for estimating one or more backscatter signals reflected from one or more objects are disclosed. In one example, a backscatter sensor includes, in part, a receiver for receiving a composite signal comprising one or more reflections of a transmitted signal, each reflection being reflected by one of a plurality of objects; and a processor configured to estimate at least a first backscatter component of the composite signal using a progressive interference cancellation technique. The first backscatter component of the composite signal corresponds to a reflection of the transmitted signal from a first object. In one embodiment, the backscatter sensor includes multiple receivers and/or one or more transmitters.
    Type: Application
    Filed: November 14, 2014
    Publication date: September 15, 2016
    Inventors: Dinesh BHARADIA, Kiran JOSHI, Sachin KATTI
  • Publication number: 20160234005
    Abstract: A system for processing signals includes an interference cancellation component that samples an RF transmit signal, transforms the sampled RF transmit signal into a self-interference cancellation signal, and combines the sampled RF transmit signal and self-interference cancellation signal to remove a first portion of interference from the RF receive signal, the combination forming a processed RF signal; and a filtering component that removes a second portion of interference from the processed signal by downconverting the processed RF signal to a processed baseband signal, sampling the processed baseband signal to create a processed digital signal, and filtering the processed digital signal to remove the second portion of interference.
    Type: Application
    Filed: April 19, 2016
    Publication date: August 11, 2016
    Inventors: Steven HONG, Sachin KATTI, Jeff MEHLMAN
  • Publication number: 20160226653
    Abstract: A MIMO wireless communication device includes, in part, a first transmit path adapted to transmit a first transmit signal from a first antenna, a second transmit path adapted to transmit a second transmit signal from a second antenna, a first receive path adapted to receive a first receive signal, an interference cancellation circuit and a controller. The cancellation circuit includes a cascaded filter structure each filter including a multitude of filter taps each including a variable element. The controller dynamically varies a value applied to each of the plurality of variable elements in accordance with frequency response characteristics of the variable element to remove a portion of a self-interference and/or cross-talk interference signal present in a signal received by the device.
    Type: Application
    Filed: September 29, 2014
    Publication date: August 4, 2016
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Dinesh BHARADIA, Sachin KATTI
  • Patent number: 9331737
    Abstract: A wireless communication device includes, in part, at least one antenna for receiving or transmitting a signal, and a cancelation circuit adapted to cancel or reduce the self-interference signal. The cancelation circuit includes, in part, a control block, N delay and attenuation paths, a combiner, and a subtractor. Each path includes a delay element and a variable attenuator whose attenuation level varies in response to a control signal generated by the control block. Each path receives a sample of the transmit signal and generates a delayed and attenuated (weighted) version of the sample signal. The combiner combines the N delayed and weighted versions of the sample signal to construct a signal representative of the self-interference signal. The subtractor subtracts the constructed signal from the received signal thereby the cancel or reduce the self-interference signal therefrom.
    Type: Grant
    Filed: June 7, 2013
    Date of Patent: May 3, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hong, Jeff Mehlman, Dinesh Bharadia, Sachin Katti
  • Patent number: 9325432
    Abstract: The current subject matter relates to a system and a method for processing signals. The system can include a transmitting antenna for transmitting a signal over a plurality of wireless spectrum fragments, a receiving antenna for receiving a signal from the plurality of wireless spectrum fragments, and a signal processing layer in communication with the transmitting and receiving antennas for simultaneously causing reception of the received signal and transmission of the transmitted signal. The signal processing layer can include an interference cancellation component for removing a first portion of interference from the received signal and a filtering component for removing a second portion of the interference from the received signal.
    Type: Grant
    Filed: February 7, 2013
    Date of Patent: April 26, 2016
    Assignee: The Board of Trustees of the Leland Stanford Junior University
    Inventors: Steven Hong, Sachin Katti, Jeff Mehlman
  • Publication number: 20140348018
    Abstract: A wireless communication device includes, in part, an analog interference cancellation circuit and a controller. The analog cancellation circuit includes a multitude of delay paths each including a delay element and a variable attenuator. The controller dynamically varies the attenuation level of each of the variable attenuators in accordance with the frequency response characteristic of that attenuator to remove a portion of a self-interference signal present in a signal received by the device. The device measures the frequency response characteristic of the communication channel, used in determining the attenuation levels, via one or more preamble symbols. A second portion of the self-interference signal is removed by the device using a multitude of samples of a transmitted signal and a multitude of samples of a signal to be transmitted.
    Type: Application
    Filed: August 11, 2014
    Publication date: November 27, 2014
    Inventors: Dinesh BHARADIA, Sachin KATTI, Emily McMILIN
  • Publication number: 20140219139
    Abstract: A circuit that cancels a self-interference signal includes, in part, a pair of signal paths that are substantially in phase, each of which paths includes a passive coupler, a delay element and a variable attenuator. The circuit further includes, in part, a first group of P signal paths each of which is substantially in phase with the pair of paths, a second group of M signal paths each of which is substantially out-of-phase relative to the pair of signal paths, and at least a pair of feedback paths. Each of the P and M signal paths, as well as the feedback paths includes a delay element and a variable attenuator. Optionally, each of the M signal paths is optionally 180° out-of-phase relative to the pair of signal paths.
    Type: Application
    Filed: February 4, 2014
    Publication date: August 7, 2014
    Applicant: Kumu Networks
    Inventors: Jung-il CHOI, Steven Hong, Mayank Jain, Sachin Katti, Philip Levis, Jeff Mehlman
  • Publication number: 20140169236
    Abstract: A circuit that cancels a self-interference signal includes, in part, a pair of signal paths that are substantially in phase, each of which paths includes a passive coupler, a delay element and a variable attenuator. The circuit further includes, in part, a first group of P signal paths each of which is substantially in phase with the pair of paths, and a second group of M signal paths each of which is substantially out-of-phase relative to the pair of signal paths. Each of the P and M signal paths includes a delay element and a variable attenuator. Furthermore, (P?1) signal paths of the first group of P signal paths, and (M?1) signal paths of the second group of M signal paths include a passive coupler. Optionally, each of the M signal paths is optionally 180° out-of-phase relative to the pair of signal paths.
    Type: Application
    Filed: December 13, 2013
    Publication date: June 19, 2014
    Applicant: Kumu Networks
    Inventors: Jung-Il CHOI, Steven HONG, Mayank JAIN, Sachin KATTI, Philip LEVIS, Jeff MEHLMAN
  • Publication number: 20130301488
    Abstract: A wireless communication device includes, in part, at least one antenna for receiving or transmitting a signal, and a cancelation circuit adapted to cancel or reduce the self-interference signal. The cancelation circuit includes, in part, a control block, N delay and attenuation paths, a combiner, and a subtractor. Each path includes a delay element and a variable attenuator whose attenuation level varies in response to a control signal generated by the control block. Each path receives a sample of the transmit signal and generates a delayed and attenuated (weighted) version of the sample signal. The combiner combines the N delayed and weighted versions of the sample signal to construct a signal representative of the self-interference signal. The subtractor subtracts the constructed signal from the received signal thereby the cancel or reduce the self-interference signal therefrom.
    Type: Application
    Filed: June 7, 2013
    Publication date: November 14, 2013
    Applicant: The Board of Trustees of the Leland Stanford Junior University
    Inventors: STEVEN HONG, Jeff Mehlman, Dinesh Bharadia, Sachin Katti