Patents by Inventor Karthik Subburaj

Karthik Subburaj 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: 20190011533
    Abstract: A frequency modulated continuous wave (FMCW) radar system is provided that includes a receiver configured to generate a digital intermediate frequency (IF) signal, and an interference monitoring component coupled to the receiver to receive the digital IF signal, in which the interference monitoring component is configured to monitor at least one sub-band in the digital IF signal for interference, in which the at least one sub-band does not include a radar signal.
    Type: Application
    Filed: August 31, 2018
    Publication date: January 10, 2019
    Inventors: Brian Paul Ginsburg, Karthik Subburaj, Karthik Ramasubramanian, Sachin Bhardwaj, Sriram Murali, Sandeep Rao
  • Publication number: 20190004167
    Abstract: The disclosure provides a radar apparatus for estimating a range of an obstacle. The radar apparatus includes a local oscillator that generates a first ramp segment and a second ramp segment. The first ramp segment and the second ramp segment each includes a start frequency, a first frequency and a second frequency. The first frequency of the second ramp segment is equal to or greater than the second frequency of the first ramp segment when a slope of the first ramp segment and a slope of the second ramp segment are equal and positive. The first frequency of the second ramp segment is equal to or less than the second frequency of the first ramp segment when the slope of the first ramp segment and the slope of the second ramp segment are equal and negative.
    Type: Application
    Filed: September 5, 2018
    Publication date: January 3, 2019
    Inventors: Sandeep Rao, Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian, Jawaharlal Tangudu, Sachin Bharadwaj
  • Patent number: 10142095
    Abstract: A integrated circuit (IC) chip can include a root timer that generates a frame pulse based on a start trigger signal. The IC chip can also include a hardware clock control that provides a clock signal based on a selected one of the frame pulse and the synchronization signal provided from one of the root timer and another IC chip. The IC chip can further include a plurality of analog to digital converters (ADCs). Each of the plurality of ADCs being configured to sample an output of a respective one of a plurality of radio frequency (RF) receivers based on the clock signal.
    Type: Grant
    Filed: October 26, 2016
    Date of Patent: November 27, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Jasbir Singh Nayyar, Brian Ginsburg, Karthik Subburaj
  • Publication number: 20180321359
    Abstract: The disclosure provides a radar apparatus. The radar apparatus includes a transmit unit that generates a first signal in response to a reference clock and a feedback clock. The first signal is scattered by one or more obstacles to generate a second signal. A receive unit receives the second signal and generates N samples corresponding to the second signal. N is an integer. A conditioning circuit is coupled to the transmit unit and the receive unit. The conditioning circuit receives the N samples corresponding to the second signal, and generates N new samples using an error between the feedback clock and the reference clock.
    Type: Application
    Filed: July 16, 2018
    Publication date: November 8, 2018
    Inventors: Sachin Bharadwaj, Karthik Subburaj
  • Patent number: 10101438
    Abstract: A noise-mitigated continuous-wave frequency-modulated radar includes, for example, a transmitter for generating a radar signal, a receiver for receiving a reflected radar signal and comprising a mixer for generating a baseband signal in response to the received radar signal and in response to a local oscillator (LO) signal, and a signal shifter coupled to at least one of the transmitter, LO input of the mixer in the receiver and the baseband signal generated by the mixer. The impact of amplitude noise or phase noise associated with interferers, namely, for example, strong reflections from nearby objects, and electromagnetic coupling from transmit antenna to receive antenna, on the detection of other surrounding objects is reduced by configuring the signal shifter in response to an interferer frequency and phase offset.
    Type: Grant
    Filed: April 15, 2015
    Date of Patent: October 16, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Karthik Ramasubramanian, Sriram Murali, Sreekiran Samala, Krishnanshu Dandu
  • Patent number: 10094920
    Abstract: The disclosure provides a radar apparatus for estimating a range of an obstacle. The radar apparatus includes a local oscillator that generates a first ramp segment and a second ramp segment. The first ramp segment and the second ramp segment each includes a start frequency, a first frequency and a second frequency. The first frequency of the second ramp segment is equal to or greater than the second frequency of the first ramp segment when a slope of the first ramp segment and a slope of the second ramp segment are equal and positive. The first frequency of the second ramp segment is equal to or less than the second frequency of the first ramp segment when the slope of the first ramp segment and the slope of the second ramp segment are equal and negative.
    Type: Grant
    Filed: August 27, 2014
    Date of Patent: October 9, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sandeep Rao, Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian, Jawaharlal Tangudu, Sachin Bharadwaj
  • Patent number: 10067221
    Abstract: A frequency modulated continuous wave (FMCW) radar system is provided that includes a receiver configured to generate a digital intermediate frequency (IF) signal, and an interference monitoring component coupled to the receiver to receive the digital IF signal, in which the interference monitoring component is configured to monitor at least one sub-band in the digital IF signal for interference, in which the at least one sub-band does not include a radar signal.
    Type: Grant
    Filed: April 6, 2015
    Date of Patent: September 4, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Brian Paul Ginsburg, Karthik Subburaj, Karthik Ramasubramanian, Sachin Bhardwaj, Sriram Murali, Sandeep Rao
  • Patent number: 10048354
    Abstract: The disclosure provides a radar apparatus. The radar apparatus includes a transmit unit that generates a first signal in response to a reference clock and a feedback clock. The first signal is scattered by one or more obstacles to generate a second signal. A receive unit receives the second signal and generates N samples corresponding to the second signal. N is an integer. A conditioning circuit is coupled to the transmit unit and the receive unit. The conditioning circuit receives the N samples corresponding to the second signal, and generates N new samples using an error between the feedback clock and the reference clock.
    Type: Grant
    Filed: August 13, 2015
    Date of Patent: August 14, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sachin Bharadwaj, Karthik Subburaj
  • Publication number: 20180172813
    Abstract: A radar system is provided that includes a radar transceiver integrated circuit (IC) configurable to transmit a first frame of chirps, and another radar transceiver IC configurable to transmit a second frame of chirps at a time delay ?T, wherein ?T=Tc/K, K?2 and Tc is an elapsed time from a start of one chirp in the first frame and the second frame and a start of a next chirp in the first frame and the second frame, wherein the radar system is configured to determine a velocity of an object in a field of view of the radar system based on first digital intermediate frequency signals generated responsive to receiving reflected chirps of the first frame and second digital IF signals generated responsive to receiving reflected chirps of the time delayed second frame, wherein the maximum measurable velocity is increased by a factor of K.
    Type: Application
    Filed: August 1, 2017
    Publication date: June 21, 2018
    Inventors: Sandeep Rao, Karthik Subburaj, Sriram Murali, Karthik Ramasubramanian
  • Publication number: 20180156910
    Abstract: A radar system is provided that includes transmission signal generation circuitry, a transmit channel coupled to the transmission generation circuitry to receive a continuous wave test signal, the transmit channel configurable to output a test signal based on the continuous wave signal in which a phase angle of the test signal is changed in discrete steps within a phase angle range, a receive channel coupled to the transmit channel via a feedback loop to receive the test signal, the receive channel including an in-phase (I) channel and a quadrature (Q) channel, a statistics collection module configured to collect energy measurements of the test signal output by the I channel and the test signal output by the Q channel at each phase angle, and a processor configured to estimate phase and gain imbalance of the I channel and the Q channel based on the collected energy measurements.
    Type: Application
    Filed: June 29, 2017
    Publication date: June 7, 2018
    Inventors: Sachin Bharadwaj, Karthik Subburaj, Sriram Murali
  • Publication number: 20180115409
    Abstract: A integrated circuit (IC) chip can include a root timer that generates a frame pulse based on a start trigger signal. The IC chip can also include a hardware clock control that provides a clock signal based on a selected one of the frame pulse and the synchronization signal provided from one of the root timer and another IC chip. The IC chip can further include a plurality of analog to digital converters (ADCs). Each of the plurality of ADCs being configured to sample an output of a respective one of a plurality of radio frequency (RF) receivers based on the clock signal.
    Type: Application
    Filed: October 26, 2016
    Publication date: April 26, 2018
    Inventors: JASBIR SINGH NAYYAR, BRIAN GINSBURG, KARTHIK SUBBURAJ
  • Publication number: 20180113196
    Abstract: A FMCW radar system with a built-in self-test (BIST) system for monitoring includes a receiver, a transmitter, and a frequency synthesizer. A FMCW chirp timing engine controls timing of operations at least one radar component. The BIST system includes at least one switchable coupling for coupling a first plurality of different analog signals including from a first plurality of selected nodes in the receiver or transmitter that are all coupled to a second number of monitor analog-to-digital converters (ADCs). The second number is less than (<) the first plurality of different analog signals. The BIST system includes a monitor timing engine and controller operating synchronously with the chirp timing engine, that includes a software configurable monitoring architecture for generating control signals including for selecting using the switchable coupling which analog signal to forward to the monitor ADC and when the monitor ADC samples the analog signals.
    Type: Application
    Filed: October 25, 2016
    Publication date: April 26, 2018
    Inventors: KARTHIK SUBBURAJ, INDU PRATHAPAN, KARTHIK RAMASUBRAMANIAN, BRIAN P. GINSBURG
  • Publication number: 20180074168
    Abstract: A noise-mitigated continuous-wave frequency-modulated radar includes, for example, a transmitter for generating a radar signal, a receiver for receiving a reflected radar signal and comprising a mixer for generating a baseband signal in response to the received radar signal and in response to a local oscillator (LO) signal, and a signal shifter coupled to at least one of the transmitter, LO input of the mixer in the receiver and the baseband signal generated by the mixer. The impact of amplitude noise or phase noise associated with interferers, namely, for example, strong reflections from nearby objects, and electromagnetic coupling from transmit antenna to receive antenna, on the detection of other surrounding objects is reduced by configuring the signal shifter in response to an interferer frequency and phase offset.
    Type: Application
    Filed: April 15, 2015
    Publication date: March 15, 2018
    Inventors: Karthik Subburaj, Karthik Ramasubramanian, Sriram Murali, Sreekiran Samala, Krishnanshu Dandu
  • Publication number: 20180038943
    Abstract: A radar system is provided that includes a receive channel including a complex baseband and a processor coupled to the receive channel to receive a first plurality of digital intermediate frequency (IF) samples from an in-band (I) channel of the complex baseband and a corresponding second plurality of digital IF samples from a quadrature (Q) channel of the complex baseband, wherein the processor is configured to execute instructions to compute at least one failure metric based on the first plurality of digital IF samples and the second plurality of digital IF samples.
    Type: Application
    Filed: August 5, 2016
    Publication date: February 8, 2018
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Jasbir Singh Nayyar
  • Patent number: 9880261
    Abstract: The disclosure provides a radar apparatus for estimating a position and a velocity of a plurality of obstacles. The radar apparatus includes a slave radar chip. A master radar chip is coupled to the slave radar chip. The master radar chip includes a local oscillator that generates a transmit signal. The slave radar chip receives the transmit signal on a first path and sends the transmit signal back to the master radar chip on a second path. A delay detect circuit is coupled to the local oscillator and receives the transmit signal from the slave radar chip on the second path and the transmit signal from the local oscillator. The delay detect circuit estimates a routing delay from the transmit signal received from the slave radar chip on the second path and from the transmit signal received from the local oscillator.
    Type: Grant
    Filed: September 30, 2014
    Date of Patent: January 30, 2018
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian
  • Publication number: 20180011170
    Abstract: In accordance with described examples, a method determines if a velocity of an object detected by a radar is greater than a maximum velocity by receiving on a plurality of receivers at least one frame of chirps transmitted by at least two transmitters and reflected off of the object. A velocity induced phase shift (?d) in a virtual array vector S of signals received by each receiver corresponding to a sequence of chirps (frame) transmitted by each transmitter is estimated. Phases of each element of virtual array vector S are corrected using ?d to generate a corrected virtual array vector Sc. A first Fourier transform is performed on the corrected virtual array vector Sc to generate a corrected virtual array spectrum to detect a signature that indicates that the object has an absolute velocity greater than a maximum velocity.
    Type: Application
    Filed: December 7, 2016
    Publication date: January 11, 2018
    Inventors: Sandeep Rao, Karthik Subburaj, Dan Wang, Adeel Ahmad
  • Publication number: 20170363714
    Abstract: A device includes a circuit board having thereon, a controlling component, a first radar chip and a second radar chip. The first radar chip includes a first radar transmission antenna, a second radar transmission antenna and a first radar receiver antenna array. The second radar chip includes a second radar receiver antenna array. The controlling component can control the first radar chip and the second radar chip. The first radar transmission antenna can transmit a first radar transmission signal. The second radar transmission antenna can transmit a second radar transmission signal. The second radar chip is spaced from the first radar chip so as to create a virtual receiver antenna array between the first radar receiver antenna array and the second radar receiver antenna array.
    Type: Application
    Filed: August 14, 2017
    Publication date: December 21, 2017
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Ginsburg, Jawaharial Tangudu, Karthik Subburaj
  • Patent number: 9829566
    Abstract: Radar detection of an object is achieved by identifying a first range associated with a possible object based on a first return from a first radar transmission having a first chirp rate, and identifying a second range associated with the possible object based on a second return from a second radar transmission having a second chirp rate that differs from the first chirp rate. The first and second ranges are evaluated together to determine whether the possible object is a true object.
    Type: Grant
    Filed: November 25, 2014
    Date of Patent: November 28, 2017
    Assignee: Texas Instruments Incorporated
    Inventors: Sandeep Rao, Karthik Subburaj
  • Publication number: 20170315211
    Abstract: The disclosure provides a radar apparatus for estimating a position and a velocity of a plurality of obstacles. The radar apparatus includes a slave radar chip. A master radar chip is coupled to the slave radar chip. The master radar chip includes a local oscillator that generates a transmit signal. The slave radar chip receives the transmit signal on a first path and sends the transmit signal back to the master radar chip on a second path. A delay detect circuit is coupled to the local oscillator and receives the transmit signal from the slave radar chip on the second path and the transmit signal from the local oscillator. The delay detect circuit estimates a routing delay from the transmit signal received from the slave radar chip on the second path and from the transmit signal received from the local oscillator.
    Type: Application
    Filed: July 6, 2017
    Publication date: November 2, 2017
    Inventors: Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian
  • Publication number: 20170299693
    Abstract: The disclosure provides a radar apparatus for estimating a position and a velocity of the plurality of obstacles. The radar apparatus includes a local oscillator that generates a first signal. A first transmit unit receives the first signal from the local oscillator and generates a first transmit signal. A frequency shifter receives the first signal from the local oscillator and generates a second signal. A second transmit unit receives the second signal and generates a second transmit signal. The frequency shifter provides a frequency offset to the first signal based on a routing delay mismatch to generate the second signal such that the first transmit signal is phase coherent with the second transmit signal.
    Type: Application
    Filed: June 28, 2017
    Publication date: October 19, 2017
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Sachin Bhardwaj