Texas Instruments Corporation

Karthik Subburaj

Karthik Ramasubramanian

Sandeep Rao

Brian Paul Ginsburg

Sriram Murali

Sreekiran Samala

Indu Prathapan

Shailesh Joshi

Jawaharlal Tangudu

Raghu Ganesan

Krishnaswamy Nagaraj

Krishnanshu Dandu

Sachin Bharadwaj

Jasbir Singh Nayyar

Sachin Bhardwaj

Vashishth Dudhia

Dan Wang

Adeel Ahmad

Daniel Colum Breen

Tom Altus

Shankar Narayanamoorthy

Anant Shankar Kamath

Jayawardan Janardhanan

Pankaj Gupta

Dheeraj Kumar Shetty

Zahir Ibrahim Parkar

Sujaata Ramalingam

Shankar Ram Narayana Moorthy

Kameswaran Vengattaramane

Anand Gadiyar

Anil Kv Kumar

Sujoy Chakravarty

Rittu Kulwant Sachdev

Saurabh Khanna

Neeraj P Nayak

Sudheer Kumar Vemulapalli

Karan Singh Bhatia

Anil Varghese Mani

Pranav Sinha

Sachin Bharadwaj, Jr

Anand Devendra Kudari

Vikas Kumar Sinha

Aswin Srinivasa Rao

Sumeer Bhatara

Dhanya Kuyilath

Dhanya K

Piyush Soni

Mayank Kumar Singh

Jawaharial Tangudu

Anjan Prasad Eswaran

Streekiran Samala

Shankar Ram Naranamoorthy

Sreekiran Smala

In some examples, a method includes receiving, at a first device, a radar signal transmitted by a second device at a transmission frequency offset from a local oscillator (LO) frequency of the first device by a target offset and reflected off a target. The method also includes determining an intermediate frequency (IF) of the radar signal based on the transmission frequency and the LO frequency. The method also includes determining a parts per million (ppm) offset between the first device and the second device based on the intermediate frequency and the target offset.

Estimating and compensating for crystal oscillator differences in a multi-crystal-oscillator radar

Systems and instruction carrying non-transitory processor-readable mediums are provided to facilitate access of radar data that may be scattered or non-uniformly located within a region of memory for further processing of such radar data. An example system includes counters that increment on different dimensions of the memory region, a lookup table, multipliers, an adder, and a wraparound mechanism to access different sets of non-contiguously stored radar data from a region of memory. The wraparound mechanism performs a wraparound operation when a combined address, generated by the adder based on addresses obtained by the multipliers, is greater than a last valid address in the region. The wraparound operation generates a new combined address that is used to fetch data from the memory. A transform operation is then performed on the fetched data.

Non-uniform multi-dimensional data access for radar data processing

A method for compressing echolocation data is provided. The method includes dividing the echolocation data into a plurality of partitions, and selecting a first partition for processing. The method also includes combining echolocation data from the first partition with echolocation data within a second partition, and combining echolocation data from the first partition with echolocation data within a third partition. The method further includes storing the combined echolocation data for all of the plurality of partitions except for the first partition in a memory.

System and method for the compression of echolocation data

A device includes a comparison circuit and a calculation circuit coupled to the comparison circuit. The comparison circuit is configured to receive a first digital input value (X) and a second digital input value (Y), and provide a first digital output value that indicates one of a first relationship, a second relationship, and a third relationship between X and Y. The calculation circuit is configured to receive X and Y, receive the first digital output value, and provide a second digital output value. The second digital output value is a first linear combination of X and Y responsive to the first digital output value indicating the first relationship, a second linear combination of X and Y responsive to the first digital output value indicating the second relationship, and a third linear combination of X and Y responsive to the first digital output value indicating the third relationship.

Linear approximation of a complex number magnitude

An apparatus comprises processor cores and computer-readable mediums storing machine instructions for the processor cores. When executing the machine instructions, the processor cores obtain received signals for transmitted chirps from a radar sensor circuit. Each transmitted chirp comprises an A chirp segment, a time gap, and a B chirp segment, respectively. The processor cores sample the received signals to obtain sampled data matrices M1(A) for the A chirp segments and M1(B) for the B chirp segments. The processor cores perform a first Fourier transform (FT) on each column of M1(A) and M1(B) to obtain velocity matrices M2(A) and M2(B), respectively. The processor cores apply a phase compensation factor to M2(B) to obtain a phase corrected velocity matrix M2(B'), and concatenate M2(A) and M2(B′) to obtain an aggregate velocity matrix M2(A&B′). The processor cores perform a second FT on each row of M2(A&B′) to obtain a range and velocity matrix M3(A&B′).

Radar system implementing segmented chirps and phase compensation for object movement

A radar transceiver includes a phase shifter that is controlled to apply an induced phase shift in a first subset of chirp signals of a frame of chirp signals, which also includes a second subset of chirp signals in which no phase shift is applied. Other circuitry generates digital signals based on received reflected signals, which are based on transmitted signals. Processing circuitry performs a Fast Fourier Transform (FFT) on a first subset of digital signals, corresponding to the first subset of chirp signals, to generate a first range-Doppler array, and performs a FFT on the second subset of digital signals, corresponding to the second subset of chirp signals, to generate a second range-Doppler array; identifies peaks in the first and second range-Doppler arrays to detect an object; and compares a phases of peaks at corresponding positions in the first and second range-Doppler arrays to determine a measured phase shift between the two peaks.

On-field phase calibration

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.

Methods and apparatus to compensate for radar system calibration changes

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.

Range resolution in FMCW radars

An example radar device includes an antenna system, a transmitter having an input, and an output coupled to an input of the antenna system, the transmitter having modulation circuitry to provide frequency modulated continuous wave (FMCW) signals for transmission by the antenna system; a receive signal processing chain; and a digital front-end. The receive signal processing chain includes an input coupled to an output of the antenna system, and is configured to receive radar reflection signals, process the radar reflected signals to generate an intermediate frequency (IF) baseband signal, and digitize the IF baseband signal to generate digital samples of the IF baseband signal. The digital front-end has an input to receive the digital samples of the IF baseband signal and to phase-shift the digital samples in response to a calibration signal.

Cascaded radar system calibration of baseband imbalances

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.

Interference detection in a frequency modulated continuous wave (FMCW) radar system

A Radix-3 butterfly circuit includes a first FIFO input configured to couple to a first FIFO. The circuit includes a first adder and first subtractor coupled to the first FIFO input, and a second FIFO input configured to couple to a second FIFO. The circuit includes a second adder and second subtractor coupled to the second FIFO input, and an input terminal coupled to the first adder and first subtractor. The circuit includes a first scaler coupled to the second adder and a first multiplexer, and a second scaler coupled to a third adder and second multiplexer. The circuit includes a third scaler coupled to a third subtractor and third multiplexer. An output of the first multiplexer is coupled to a complex multiplier. An output of the second multiplexer is coupled to a second FIFO output. An output of the third multiplexer is coupled to a first FIFO output.

Multi-dimensional FFT computation pipelined hardware architecture using Radix-3 and Radix-2butterflies

A device comprises a digital ramp generator, an oscillator, a power amplifier, a low-noise amplifier (LNA), a mixer, and an intermediate frequency amplifier (IFA). The oscillator generates a chirp signal based on an output from the digital ramp generator. The power amplifier receives the chirp signal and outputs an amplified chirp signal to a transmitter antenna. The LNA receives a reflected chirp signal from a receiver antenna. The mixer receives output of the LNA and combines it with the chirp signal from the oscillator. The IFA receives the mixer output signal and includes a configurable high-pass filter, which has a first cutoff frequency during a first portion of the chirp signal and a second cutoff frequency during a second portion of the chirp signal. In some implementations, the first cutoff frequency is chosen based on a frequency of a blocker signal introduced by couplings between the transmitter and receiver antennas.

Intermediate frequency amplifier with a configurable high-pass filter

A system includes a memory configured to store a two-dimensional data structure that includes radar data arranged such that radar data of a first transmitter is separated from radar data of a second transmitter by a Doppler offset in the two-dimensional data structure. The system also includes a data fetch mechanism that includes a lookup table (LUT) applied on either of two dimensions. The lookup table is configured to store a data fetch location in the two-dimensional data structure, where the data fetch location indicates a location from which to fetch a subset of the radar data from the two-dimensional data structure and the data fetch mechanism is configured to fetch the subset of the radar data from the two-dimensional data structure based on the LUT. The system includes a processor configured to perform a fast Fourier transform (FFT) on the fetched subset of the radar data.

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 (φ) 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 φto generate a corrected virtual array vector S. A first Fourier transform is performed on the corrected virtual array vector Sto generate a corrected virtual array spectrum to detect a signature that indicates that the object has an absolute velocity greater than a maximum velocity.

Methods and apparatus for velocity detection in MIMO radar including velocity ambiguity resolution

A system includes a shift register to store data samples, where the shift register includes a cell under test (CUT), a left guard cell, a right guard cell, a left window, and a right window. The system includes two sets of comparators to compare incoming data samples with data samples in the left window and the right window to compute ranks of the incoming data samples. The system includes a sorted index array to store a rank of the data samples in the shift register. The system includes a selector to select a Kth smallest index from the sorted index array and its corresponding data sample from the shift register. The system includes a target comparator, where the first comparator input receives a data sample from the CUT and the second comparator input receives a Kth smallest data sample, and the comparator output indicates a CFAR target detection.

CFAR OS detection hardware with two sets of comparators

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Bengaluru, India

Karthik Subburaj