Patents by Inventor Karthik Ramasubramanian

Karthik Ramasubramanian 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: 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
  • Publication number: 20170285140
    Abstract: A FMCW radar receiver includes a LO providing a chirped LO signal, an in-phase (I) channel for outputting I-data and a quadrature (Q) channel for outputting Q-data. A dynamic correction parameter generator generates IQ phase correction values (P[n]s) and IQ gain correction values (G[n]s) based on a frequency slope rate of the chirped LO signal for generating during intervals of chirps including a first sequence of P[n]s and G[n]s during a first chirp and a second sequence of P[n]s and G[n]s during a second chirp. An IQ mismatch (IQMM) correction circuit has a first IQMM input coupled to receive the I-data and a second IQMM input receiving the Q-data, and the P[n]s and G[n]s. During the first chirp the IQMM correction circuit provides first Q?-data and first I?-data and during the second chirp the IQMM correction circuit provides at least second Q?-data and second I?-data.
    Type: Application
    Filed: April 1, 2016
    Publication date: October 5, 2017
    Inventors: PANKAJ GUPTA, SRIRAM MURALI, KARTHIK RAMASUBRAMANIAN
  • Patent number: 9753120
    Abstract: The disclosure provides a radar apparatus fur estimating a distance of the one or more obstacles in a range of interest. The radar apparatus includes a local oscillator that generates a first ramp segment having a first start frequency. A frequency shifter receives the first ramp segment and generates a transmit signal and a mixer signal. The transmit signal is scattered by a one or more obstacles in the range of interest to generate the scattered signal. A mixer mixes the scattered signal and the mixer signal to generate a non-zero IF signal which is filtered to generate a filtered non-zero IF signal. An ADC (analog to digital converter) samples the filtered non-zero IF signal to generate a valid data. A DSP (digital signal processor) processes the valid data for estimating the distance of the one or more obstacles.
    Type: Grant
    Filed: October 22, 2014
    Date of Patent: September 5, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Ramasubramanian, Sandeep Rao
  • Patent number: 9733340
    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: Grant
    Filed: November 21, 2014
    Date of Patent: August 15, 2017
    Assignee: Texas Instruments Incorporated
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Ginsburg, Jawaharlal Tangudu, Karthik Subburaj
  • Publication number: 20170212214
    Abstract: A radar system is provided that includes a receive channel configured to receive a reflected signal and to generate a first digital intermediate frequency (IF) signal based on the reflected signal, a reference receive channel configured to receive a reflected signal and to generate a second digital IF signal based on the reflected signal, and digital mismatch compensation circuitry coupled to receive the first digital IF signal and the second digital IF signal, the digital mismatch compensation circuitry configured to process the first digital IF signal and the second digital IF signal to compensate for mismatches between the receive channel and the reference receive channel.
    Type: Application
    Filed: January 22, 2016
    Publication date: July 27, 2017
    Inventors: Sriram Murali, Karthik Subburaj, Karthik Ramasubramanian
  • Publication number: 20170192847
    Abstract: Data memory protection is provided for a signal processing system such as a radar system in which the data memory is protected with a common set of parity bits rather than requiring a set of parity bits for each memory word as in Error Correction Coded (ECC) memories. The common set of parity bits may be updated as memory words in the data memory are accessed as part of signal processing of one or more digital signals. The memory protection ensures that in the absence of memory errors the common parity bits are zero at the end of processing the digital signals as long as each word in the data memory that is used for storing the signal processing data is written and read an equal number of times.
    Type: Application
    Filed: December 31, 2015
    Publication date: July 6, 2017
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Paul Ginsburg
  • Publication number: 20170181097
    Abstract: Systems and methods are provided for packet detection in a wireless local area network transceiver. An antenna is configured to receive a signal, having a carrier frequency. A mixer is configured to mix the received signal with one of the in-phase and quadrature components of the local oscillator to produce a corresponding one of an in-phase downconverted signal and a quadrature phase downconverted signal. A packet detector is configured to determine, from the one of the in-phase downconverted signal and the quadrature phase downconverted signal, if the signal contains a packet of data and instruct a set of components associated with an other of the in-phase and quadrature components of the local oscillator to activate to process the received signal.
    Type: Application
    Filed: December 17, 2015
    Publication date: June 22, 2017
    Inventors: RAGHU GANESAN, KARTHIK RAMASUBRAMANIAN, SARMA S. GUNTURI
  • Patent number: 9612338
    Abstract: A method of acquiring a satellite signal in a GNSS receiver includes multiplying a received signal with a hypothesized doppler frequency signal to generate a frequency shifted signal. A PN code sequence signal is multiplied with the frequency shifted signal to generate a PN wiped signal. A windowing function signal is multiplied with the PN wiped signal to generate a windowed signal. The windowed signal is integrated coherently for a first predefined time to generate a coherent accumulated data.
    Type: Grant
    Filed: September 25, 2013
    Date of Patent: April 4, 2017
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Karthik Ramasubramanian, Jawaharlal Tangudu
  • Publication number: 20170090014
    Abstract: Methods for monitoring of performance parameters of one or more receive channels and/or one or more transmit channels of a radar system-on-a-chip (SOC) are provided. The radar SOC may include a loopback path coupling at least one transmit channel to at least one receive channel to provide a test signal from the at least one transmit channel to the at least one receive channel when the radar SOC is operated in test mode. In some embodiments, the loopback path includes a combiner coupled to each of one or more transmit channels, a splitter coupled to each of one or more receive channels, and a single wire coupling an output of the combiner to an input of the splitter.
    Type: Application
    Filed: September 30, 2015
    Publication date: March 30, 2017
    Inventors: Karthik Subburaj, Brian Paul Ginsburg, Daniel Colum Breen, Sandeep Rao, Karthik Ramasubramanian
  • Publication number: 20170074974
    Abstract: The disclosure provides a radar apparatus. The radar apparatus includes a transmitter that transmits a first chirp. The first chirp is scattered by one or more obstacles to generate a first plurality of scattered signals. A plurality of receivers receives the first plurality of scattered signals. Each receiver of the plurality of receivers generates a digital signal in response to a scattered signal of the first plurality of scattered signals. A processor is coupled to the plurality of receivers and receives the digital signals from the plurality of receivers. The processor performs range FFT (fast fourier transform) and angle FFT on the digital signals received from the plurality of receivers to generate a first matrix of complex samples.
    Type: Application
    Filed: September 15, 2015
    Publication date: March 16, 2017
    Inventors: Sandeep RAO, Karthik RAMASUBRAMANIAN
  • Publication number: 20170054449
    Abstract: A radar system is provided that includes a compression component configured to compress blocks of range values to generate compressed blocks of range values, and a radar data memory configured to store compressed blocks of range values generated by the compression component.
    Type: Application
    Filed: March 4, 2016
    Publication date: February 23, 2017
    Inventors: Anil Mani, Sandeep Rao, Karthik Ramasubramanian
  • Publication number: 20170023663
    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: September 30, 2014
    Publication date: January 26, 2017
    Inventors: Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian
  • Publication number: 20160291130
    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: April 6, 2015
    Publication date: October 6, 2016
    Inventors: Brian Paul Ginsburg, Karthik Subburaj, Karthik Ramasubramanian, Sachin Bhardwaj, Sriram Murali, Sandeep Rao
  • Publication number: 20160187462
    Abstract: A radar device is provided that includes a timing control component operable to generate, for each chirp of a sequence of chirps according to a set of chirp configuration parameters and a chirp profile for the chirp, chirp control signals to cause the radar device to transmit the chirp, the timing control component having chirp configuration parameter inputs, chirp profile parameter inputs, a chirp address output, and chirp control signal outputs, a chirp configuration storage component having chirp configuration parameter outputs coupled to corresponding inputs of the configuration parameter inputs of the timing control component, a chirp profile address output, and a chirp address input coupled to the chirp address output, and a chirp profile storage component having chirp profile parameter outputs coupled to the chirp profile parameter inputs of the timing control component; and a chirp profile address input coupled to the chirp profile address output.
    Type: Application
    Filed: December 30, 2014
    Publication date: June 30, 2016
    Inventors: Tom Altus, Jasbir Singh Nayyar, Karthik Ramasubramanian, Brian Paul Ginsburg
  • Patent number: 9356650
    Abstract: An integrated circuit for facilitating spread spectrum reception of data having a data bit period includes an hypothesis search circuit (120, 210, 220) operable to correlate a pseudorandom code with a signal input based on a received signal to produce correlation results, and a processor circuit (320) operable to coherently integrate the correlation results over plural sample windows (PreD1, PreD2) staggered relative to each other in the coherent integration interval and to non-coherently combine the coherently integrated results corresponding to the plural sample windows (PreD1, PreD2) to produce a received signal output, whereby enhancing performance. Other circuits, receivers and processes are also disclosed.
    Type: Grant
    Filed: December 5, 2014
    Date of Patent: May 31, 2016
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sunil Chomal, Karthik Ramasubramanian, Jawaharlal Tangudu, Hemanth Mullur
  • Publication number: 20160146931
    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: November 21, 2014
    Publication date: May 26, 2016
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Ginsburg, Jawaharlal Tangudu, Karthik Subbaraj
  • Publication number: 20160116570
    Abstract: The disclosure provides a radar apparatus fur estimating a distance of the one or more obstacles in a range of interest. The radar apparatus includes a local oscillator that generates a first ramp segment having a first start frequency. A frequency shifter receives the first ramp segment and generates a transmit signal and a mixer signal. The transmit signal is scattered by a one or more obstacles in the range of interest to generate the scattered signal. A mixer mixes the scattered signal and the mixer signal to generate a non-zero IF signal which is filtered to generate a filtered non-zero IF signal. An ADC (analog to digital converter) samples the filtered non-zero IF signal to generate a valid data. A DSP (digital signal processor) processes the valid data for estimating the distance of the one or more obstacles.
    Type: Application
    Filed: October 22, 2014
    Publication date: April 28, 2016
    Inventors: Karthik Ramasubramanian, Sandeep Rao
  • Publication number: 20160061942
    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: August 27, 2014
    Publication date: March 3, 2016
    Inventors: Sandeep Rao, Karthik Subburaj, Brian Ginsburg, Karthik Ramasubramanian, Jawaharlal Tangudu, Sachin Bharadwaj
  • Publication number: 20150276918
    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: March 3, 2015
    Publication date: October 1, 2015
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Sachin Bhardwaj