Patents by Inventor Apu Sivadas

Apu Sivadas 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: 11693107
    Abstract: According to an aspect, a radar system comprising a transmitter operative to transmit a first set of chirps on a single transmit antenna and a second set of chirps on a plurality of transmit antennas, in that, the first set of chirps forming a first part of a chirp frame and the second set of chirps forming a second part of the chirp frame, a first receiver segment operative to generate a first set of parameters from a first set of received chirps that is reflection of the first set of chirps from one or more objects and a second segment operative to generate a second set of parameters from a second set of received chirps that is reflection of the second set of chirps from the one or more objects part of the received chirp frame and the first set of parameters, wherein, first set of parameters and second set of parameters comprise at least one of range doppler and angle of one or more objects.
    Type: Grant
    Filed: December 15, 2020
    Date of Patent: July 4, 2023
    Inventors: Gireesh Rajendran, Ankit Sharma, Sai Gunaranjan Pelluri, Apu Sivadas
  • Publication number: 20230204715
    Abstract: According to an aspect, a method of determining Doppler in a radar system comprising receiving a set of chirps, sampling in time the set of chirps to generate a set of non-uniform samples with one sample per chirp that is non-uniform in time in each chirp across the set of chirps, generating a first Doppler frequency from the set of non-uniform samples, generating a set of non-aliased Doppler frequencies for the first Doppler frequencies from a corresponding set of hypothesis, determining a first set of angles of arrival for every non-aliased Doppler frequency in the a set of non-aliased Doppler frequencies and selecting a first non-aliased Doppler frequency in the set of non-aliased Doppler frequencies that corresponds to the first angle of arrival with a minimum error in the a set of angles of arrival.
    Type: Application
    Filed: March 15, 2022
    Publication date: June 29, 2023
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Apu Sivadas, Gireesh Rajendran, Sai Gunaranjan Pelluri, Ankit Sharma
  • Publication number: 20230152436
    Abstract: According to an aspect, a method of determining two dimensional (2D) angle of arrival (AoA) in a radar system comprising determining one dimensional (1D) AoA to generate a first set of (AoA), selecting a set of valid 1D AoA angles from the first set AoA, and determining the 2D AoA from the set of valid 1D AoA, Wherein the 1D AoA is determined on a first set of data received over a first uniform linear antenna array arranged in the first axis and the 2D AoA is determined on a second set data received over the first and the second MIMO antenna array arranged in the second axis and the set of valid 1D AoA in the first axis. Wherein the second antenna array need not be orthogonal to the first linear antenna array.
    Type: Application
    Filed: January 13, 2022
    Publication date: May 18, 2023
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Ankit Sharma, Dibakar Sil, Sai Gunaranjan Pelluri, Apu Sivadas, Gireesh Rajendran
  • Patent number: 11520004
    Abstract: According to an aspect, method of enhancing a resolution in a radar system having an antenna aperture comprises measuring a first radiation pattern corresponding to a first set of receiving antennas by feeding a known radio frequency (RF) signal over the first set of receiving antennas, wherein the first set of radiation due to an impairment, coherently combining an interpolated radiation pattern with a received radar signal received by the set of receiving antenna when employed for an object detection, to generate a high signal to noise ratio (SNR) received signal, and iteratively combining the high SNR received signal with the interpolated signal to reduce the error due to the impairment.
    Type: Grant
    Filed: January 16, 2020
    Date of Patent: December 6, 2022
    Inventors: Sachin Bharadwaj, Sai Gunaranjan Pelluri, Sumeer Bhatara, Apu Sivadas
  • Publication number: 20220099819
    Abstract: According to an aspect, a radar system comprising a transmitter operative to transmit a first set of chirps on a single transmit antenna and a second set of chirps on a plurality of transmit antennas, in that, the first set of chirps forming a first part of a chirp frame and the second set of chirps forming a second part of the chirp frame, a first receiver segment operative to generate a first set of parameters from a first set of received chirps that is reflection of the first set of chirps from one or more objects and a second segment operative to generate a second set of parameters from a second set of received chirps that is reflection of the second set of chirps from the one or more objects part of the received chirp frame and the first set of parameters, wherein, first set of parameters and second set of parameters comprise at least one of range doppler and angle of one or more objects.
    Type: Application
    Filed: December 15, 2020
    Publication date: March 31, 2022
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Gireesh Rajendran, Ankit Sharma, Sai Gunaranjan Pelluri, Apu Sivadas
  • Patent number: 11092686
    Abstract: A method in a time switched multiple input and multiple output (MIMO) radar system comprising, receiving (610) from an antenna array a plurality of data points representing a radar signal reflected from plurality of objects, forming (620) a first set of beams from the plurality of data points, wherein the first set of beams are making a first set angles with a normal to the antenna array, detecting a set of objects (410A-L) from the first set of beams, determining (630) a set of Doppler frequencies of the set of objects, computing (650) a self-velocity representing a velocity of the antenna array from the set of Doppler frequencies and the first set of angles, and correcting (660) the plurality of data points using the self-velocity and a second set of angles to generate plurality of corrected data points.
    Type: Grant
    Filed: December 5, 2018
    Date of Patent: August 17, 2021
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Patent number: 11047972
    Abstract: A multichannel radar system comprising a set of antennas each receiving a sequence of chirps reflected from plurality of objects, a range detector generating a set of range bins for each chirp, a beam former operative to generate a set of dominant frequency components from a group of range bins picked from the set of range bins across the set of antennas, a nearness detector for separating the set of dominant frequencies into a first set of dominant frequencies and a second set of dominant frequencies, a frequency subtractor configured to shift the each dominant frequency in the first set of dominant frequencies by its phase by a first value to form a third set of phase shifted dominant frequencies, and a Doppler estimator estimating a Doppler frequency of the each dominant frequency in the set of dominant frequencies from the third set of phase shifted dominant frequencies and the second set of dominant frequencies.
    Type: Grant
    Filed: March 21, 2019
    Date of Patent: June 29, 2021
    Inventors: Apu Sivadas, Gireesh Rajendran
  • Patent number: 11041941
    Abstract: An object detection system comprises a first object detection unit detecting an object from a first radio frequency (RF) signal data comprising first set of characteristics representing a first object, a second object detection unit detecting the object from an optical image data and a calibration unit calibrating the first RF signal data from the optical image data, in that, the second object detection unit and the first object detection unit are aligned to detect the object in a first region.
    Type: Grant
    Filed: May 1, 2018
    Date of Patent: June 22, 2021
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Publication number: 20210141053
    Abstract: According to an aspect, method of enhancing a resolution in a radar system having an antenna aperture comprises measuring a first radiation pattern corresponding to a first set of receiving antennas by feeding a known radio frequency (RF) signal over the first set of receiving antennas, wherein the first set of radiation due to an impairment, coherently combining an interpolated radiation pattern with a received radar signal received by the set of receiving antenna when employed for an object detection, to generate a high signal to noise ratio (SNR) received signal, and iteratively combining the high SNR received signal with the interpolated signal to reduce the error due to the impairment.
    Type: Application
    Filed: January 16, 2020
    Publication date: May 13, 2021
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Sachin Bharadwaj, Sai Gunaranjan Pelluri, Sumeer Bhatara, Apu Sivadas
  • Patent number: 10784215
    Abstract: According to an aspect of the present invention, an electronic system (499) operative on a millimeter signal comprises an integrated circuit (401) comprising a first solder ball (420A) and a second solder ball (420B) respectively coupled to a positive and a negative signal interface points (412 and 413) of a differential millimeter signal on a die (410) housed in the integrated circuit (401), wherein the first and the second solder balls (420A and 420B) are positioned one behind other from an edge of the integrated circuit (401) and a three-path coplanar waveguide (CPW) comprising a center path (495B) and a two adjacent paths (495A and 495C) formed on a printed circuit board (PCB) (490) such that the center path (495B) is coupled to the first solder ball that is in front and the two adjacent paths coupled to the second solder ball that is behind the first solder ball.
    Type: Grant
    Filed: February 4, 2019
    Date of Patent: September 22, 2020
    Inventors: Apu Sivadas, Alok Prakash Joshi, Gireesh Rajendran
  • Publication number: 20200241125
    Abstract: A multichannel radar system comprising a set of antennas each receiving a sequence of chirps reflected from plurality of objects, a range detector generating a set of range bins for each chirp, a beam former operative to generate a set of dominant frequency components from a group of range bins picked from the set of range bins across the set of antennas, a nearness detector for separating the set of dominant frequencies into a first set of dominant frequencies and a second set of dominant frequencies, a frequency subtractor configured to shift the each dominant frequency in the first set of dominant frequencies by its phase by a first value to form a third set of phase shifted dominant frequencies, and a Doppler estimator estimating a Doppler frequency of the each dominant frequency in the set of dominant frequencies from the third set of phase shifted dominant frequencies and the second set of dominant frequencies.
    Type: Application
    Filed: March 21, 2019
    Publication date: July 30, 2020
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Apu Sivadas, Gireesh Rajendran
  • Publication number: 20200161257
    Abstract: According to an aspect of the present invention, an electronic system (499) operative on a millimeter signal comprises an integrated circuit (401) comprising a first solder ball (420A) and a second solder ball (420B) respectively coupled to a positive and a negative signal interface points (412 and 413) of a differential millimeter signal on a die (410) housed in the integrated circuit (401), wherein the first and the second solder balls (420A and 420B) are positioned one behind other from an edge of the integrated circuit (401) and a three-path coplanar waveguide (CPW) comprising a center path (495B) and a two adjacent paths (495A and 495C) formed on a printed circuit board (PCB) (490) such that the center path (495B) is coupled to the first solder ball that is in front and the two adjacent paths coupled to the second solder ball that is behind the first solder ball.
    Type: Application
    Filed: February 4, 2019
    Publication date: May 21, 2020
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Apu Sivadas, Alok Prakash Joshi, Gireesh Rajendran
  • Publication number: 20200088867
    Abstract: A method in a time switched multiple input and multiple output (MIMO) radar system comprising, receiving (610) from an antenna array a plurality of data points representing a radar signal reflected from plurality of objects, forming (620) a first set of beams from the plurality of data points, wherein the first set of beams are making a first set angles with a normal to the antenna array, detecting a set of objects (410A-L) from the first set of beams, determining (630) a set of Doppler frequencies of the set of objects, computing (650) a self-velocity representing a velocity of the antenna array from the set of Doppler frequencies and the first set of angles, and correcting (660) the plurality of data points using the self-velocity and a second set of angles to generate plurality of corrected data points.
    Type: Application
    Filed: December 5, 2018
    Publication date: March 19, 2020
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Publication number: 20190265330
    Abstract: An object detection system comprises a first object detection unit detecting an object from a first radio frequency (RF) signal data comprising first set of characteristics representing a first object, a second object detection unit detecting the object from an optical image data and a calibration unit calibrating the first RF signal data from the optical image data, in that, the second object detection unit and the first object detection unit are aligned to detect the object in a first region.
    Type: Application
    Filed: May 1, 2018
    Publication date: August 29, 2019
    Applicant: Steradian Semiconductors Private Limited
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Patent number: 10281575
    Abstract: In an embodiment of the present disclosure, a Radar transceiver for object detection comprises a two dimensional antenna array receiving plurality of a reflected radio frequency (RF) signals, a mux-adder selectively adding the reflected RF signals in first mode and selectively multiplexing the reflected RF signals in a second mode, a range bin detector determining a valid range bins in the first mode and a three dimensional (3D) image reconstructor operating on the valid range bins to reconstruct a 3D image of the object in the second mode. In that the two dimensional antenna array comprises antenna elements arranged in K rows and M columns, and the mux-adder adds a RF signal received on the M columns of each row in the first mode. The mux-adder multiplexes the RF signal received on the M columns of each row in the second mode.
    Type: Grant
    Filed: December 1, 2016
    Date of Patent: May 7, 2019
    Assignee: Steradian Semiconductors Private Limited
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Publication number: 20180088229
    Abstract: In an embodiment of the present disclosure, a Radar transceiver for object detection comprises a two dimensional antenna array receiving plurality of a reflected radio frequency (RF) signals, a mux-adder selectively adding the reflected RF signals in first mode and selectively multiplexing the reflected RF signals in a second mode, a range bin detector determining a valid range bins in the first mode and a three dimensional (3D) image reconstructor operating on the valid range bins to reconstruct a 3D image of the object in the second mode. In that the two dimensional antenna array comprises antenna elements arranged in K rows and M columns, and the mux-adder adds a RF signal received on the M columns of each row in the first mode. The mux-adder multiplexes the RF signal received on the M columns of each row in the second mode.
    Type: Application
    Filed: December 1, 2016
    Publication date: March 29, 2018
    Inventors: Gireesh Rajendran, Apu Sivadas
  • Patent number: 9893702
    Abstract: A notch filter including an inductor-capacitor tuning circuit is disclosed. The inductor-capacitor tuning circuit may determine a frequency response of the notch filter in accordance with an associated resonant frequency. In some exemplary embodiments, the inductor-capacitor circuit may include a differential inductor divided at a symmetry point and a variable capacitor coupled to the differential inductor at the symmetry point.
    Type: Grant
    Filed: July 27, 2015
    Date of Patent: February 13, 2018
    Assignee: QUALCOMM Incorporated
    Inventors: Gireesh Rajendran, Alok Prakash Joshi, Apu Sivadas
  • Publication number: 20170033757
    Abstract: A notch filter including an inductor-capacitor tuning circuit is disclosed. The inductor-capacitor tuning circuit may determine a frequency response of the notch filter in accordance with an associated resonant frequency. In some exemplary embodiments, the inductor-capacitor circuit may include a differential inductor divided at a symmetry point and a variable capacitor coupled to the differential inductor at the symmetry point.
    Type: Application
    Filed: July 27, 2015
    Publication date: February 2, 2017
    Inventors: Gireesh Rajendran, Alok Prakash Joshi, Apu Sivadas
  • Patent number: 9450546
    Abstract: According to an aspect of present disclosure, a set of power amplifiers are used to amplify power of a signal for transmission. The signal powers from a set of power amplifiers are coupled to set of primary windings which are commonly coupled to a secondary winding such that the powers on the primary windings are additive in the secondary winding. A current path on the primary side is provided for flow of a current that is induced on at least one primary winding when a power amplifier coupled to that primary winding is in “off” state. As a result, the induced current is prevented from flowing in to the power amplifier that are in “on” state. Further, the current path isolates the power amplifiers from each other thereby enabling the power amplifiers to operate at the rated efficiency. In one embodiment, the current path is provided using a resistor network.
    Type: Grant
    Filed: January 27, 2014
    Date of Patent: September 20, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Apu Sivadas, Alok Joshi, Krishnaswamy Thiagarajan, Rakesh Kumar
  • Publication number: 20160126895
    Abstract: An I converter outputs I sign data and I magnitude data based on received I data. A Q converter outputs Q sign data and Q magnitude data based on received Q data. An I clock generates an I phase based ort the I sign data. A Q clock generates a Q phase based on the Q sign data. An I modulator generates an I magnitude pulse stream based on the I magnitude data. A Q modulator generates a Q magnitude pulse stream based on the Q magnitude data. A digital logic component generates an output signal based on the I phase, the I magnitude pulse stream, the Q phase and the Q magnitude pulse stream. A power amplifier generates an amplified signal based on the output signal.
    Type: Application
    Filed: October 30, 2014
    Publication date: May 5, 2016
    Inventors: Gireesh Rajendran, Rakesh Kumar, Alok Prakask Joshi, Subhashish Mukherjee, Krishnaswamy Thiagarajan, Apu Sivadas