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: 20200363502
    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: August 4, 2020
    Publication date: November 19, 2020
    Inventors: KARTHIK SUBBURAJ, INDU PRATHAPAN, KARTHIK RAMASUBRAMANIAN, BRIAN P. GINSBURG
  • Publication number: 20200363518
    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 4, 2020
    Publication date: November 19, 2020
    Inventors: Sandeep Rao, Karthik Subburaj, Sriram Murali, Karthik Ramasubramanian
  • Patent number: 10809353
    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: August 28, 2018
    Date of Patent: October 20, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Karthik Ramasubramanian, Sriram Murali, Sreekiran Samala, Krishnanshu Dandu
  • Publication number: 20200319296
    Abstract: A system includes a hardware accelerator configured to perform a two-dimensional (2D) fast Fourier transform (FFT) on an M×N element array. The hardware accelerator has log2 M×N pipeline stages including an initial group of log2 M stages and a final group of log2 N stages. Each stage includes a butterfly unit, a FIFO buffer coupled to the butterfly unit, and a multiplier coupled to the butterfly unit and to an associated twiddle factor table. The hardware accelerator also includes butterfly control logic to provide elements of the M×N element array to the initial group of stages in an N direction of the array, and twiddle factor addressing logic to, for the twiddle factor tables of the initial group of stages, apply an indexed entry of the twiddle factor table to the associated multiplier. The indexed entry begins as a first entry and advances by N entries after every N cycles.
    Type: Application
    Filed: April 5, 2019
    Publication date: October 8, 2020
    Inventors: Pankaj GUPTA, Karthik RAMASUBRAMANIAN
  • Publication number: 20200309939
    Abstract: Aspects of the present disclosure provide for a radar system including a radar IC including a timing engine, a local oscillator, and a modulator. The timing engine is configured to generate one or more chirp control signals. The local oscillator is configured to receive the one or more chirp control signals and generate a frame including a first sequence of chirps according to the one or more chirp control signals. The modulator is configured to modulate the first sequence of chirps to generate a second sequence of chirps so the frame includes the first sequence of chirps and the second sequence of chirps offset by a first frequency value.
    Type: Application
    Filed: March 25, 2019
    Publication date: October 1, 2020
    Inventors: Karthik SUBBURAJ, Sandeep RAO, Sriram MURALI, Karthik RAMASUBRAMANIAN
  • Patent number: 10782389
    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: August 14, 2017
    Date of Patent: September 22, 2020
    Assignee: Texas Instruments Incorporated
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Ginsburg, Jawaharial Tangudu, Karthik Subburaj
  • Patent number: 10775489
    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: Grant
    Filed: August 1, 2017
    Date of Patent: September 15, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sandeep Rao, Karthik Subburaj, Sriram Murali, Karthik Ramasubramanian
  • Patent number: 10768278
    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: Grant
    Filed: October 25, 2016
    Date of Patent: September 8, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Indu Prathapan, Karthik Ramasubramanian, Brian P. Ginsburg
  • Publication number: 20200225318
    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: March 31, 2020
    Publication date: July 16, 2020
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Jasbir Singh Nayyar
  • Publication number: 20200209353
    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: March 12, 2020
    Publication date: July 2, 2020
    Inventors: Karthik Subburaj, Brian Paul Ginsburg, Daniel Colum Breen, Sandeep Rao, Karthik Ramasubramanian
  • Publication number: 20200174884
    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: February 11, 2020
    Publication date: June 4, 2020
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Paul Ginsburg
  • Patent number: 10649069
    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: Grant
    Filed: June 28, 2017
    Date of Patent: May 12, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Sachin Bhardwaj
  • Patent number: 10641866
    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: Grant
    Filed: August 5, 2016
    Date of Patent: May 5, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Ramasubramanian, Karthik Subburaj, Jasbir Singh Nayyar
  • Publication number: 20200132810
    Abstract: Methods, apparatus, systems and articles of manufacture to compensate radar system calibration are disclosed. A radio-frequency (RF) subsystem having a transmit channel, a receive channel, and a loopback path comprising at least a portion of the transmit channel and at least a portion of the receive channel, a loopback measurer to measure a first loopback response of the RF subsystem for a first calibration configuration of the RF subsystem, and to measure a second loopback response of the RF subsystem for a second calibration configuration of the RF subsystem, and a compensator to adjust at least one of a transmit programmable shifter or a digital front end based on a difference between the first loopback response and the second loopback response to compensate for a loopback response change when the RF subsystem is changed from the first calibration configuration to the second calibration configuration.
    Type: Application
    Filed: July 16, 2019
    Publication date: April 30, 2020
    Inventors: Karthik Subburaj, Shankar Narayanamoorthy, Karthik Ramasubramanian, Anand Gadiyar, Dheeraj Kumar Shetty, Shailesh Joshi
  • Patent number: 10598767
    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: Grant
    Filed: January 22, 2019
    Date of Patent: March 24, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Karthik Subburaj, Brian Paul Ginsburg, Daniel Colum Breen, Sandeep Rao, Karthik Ramasubramanian
  • Patent number: 10599518
    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: Grant
    Filed: December 31, 2015
    Date of Patent: March 24, 2020
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Brian Paul Ginsburg
  • Publication number: 20200025871
    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: August 28, 2018
    Publication date: January 23, 2020
    Inventors: Karthik Subburaj, Karthik Ramasubramanian, Sriram Murali, Sreekiran Samala, Krishnanshu Dandu
  • Publication number: 20190331765
    Abstract: A radar hardware accelerator (HWA) includes a fast Fourier transform (FFT) engine including a pre-processing block for providing interference mitigation and/or multiplying a radar data sample stream received from ADC buffers within a split accelerator local memory that also includes output buffers by a pre-programmed complex scalar or a specified sample from an internal look-up table (LUT) to generate pre-processed samples. A windowing plus FFT block (windowed FFT block) is for multiply the pre-processed samples by a window vector and then processing by an FFT block for performing a FFT to generate Fourier transformed samples. A post-processing block is for computing a magnitude of the Fourier transformed samples and performing a data compression operation for generating post-processed radar data. The pre-processing block, windowed FFT block and post-processing block are connected in one streaming series data path.
    Type: Application
    Filed: June 14, 2019
    Publication date: October 31, 2019
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Indu Prathapan, Raghu Ganesan, Pankaj Gupta
  • Patent number: 10330773
    Abstract: A radar hardware accelerator (HWA) includes a fast Fourier transform (FFT) engine including a pre-processing block for providing interference mitigation and/or multiplying a radar data sample stream received from ADC buffers within a split accelerator local memory that also includes output buffers by a pre-programmed complex scalar or a specified sample from an internal look-up table (LUT) to generate pre-processed samples. A windowing plus FFT block (windowed FFT block) is for multiply the pre-processed samples by a window vector and then processing by an FFT block for performing a FFT to generate Fourier transformed samples. A post-processing block is for computing a magnitude of the Fourier transformed samples and performing a data compression operation for generating post-processed radar data. The pre-processing block, windowed FFT block and post-processing block are connected in one streaming series data path.
    Type: Grant
    Filed: June 16, 2016
    Date of Patent: June 25, 2019
    Assignee: TEXAS INSTRUMENTS INCORPORATED
    Inventors: Sandeep Rao, Karthik Ramasubramanian, Indu Prathapan, Raghu Ganesan, Pankaj Gupta
  • Publication number: 20190154797
    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: January 22, 2019
    Publication date: May 23, 2019
    Inventors: Karthik Subburaj, Brian Paul Ginsburg, Daniel Colum Breen, Sandeep Rao, Karthik Ramasubramanian