Texas Instruments Corporation

Cisco Technology, Inc.

Sandeep Rao

Karthik Ramasubramanian

Karthik Subburaj

Brian Paul Ginsburg

Deric Wayne Waters

Sriram Murali

Goutam Dutta

Jawaharlal Tangudu

Dan Wang

Adeel Ahmad

Anil Varghese Mani

Tarkesh Pande

Jayawardan Janardhanan

Sthanunathan Ramakrishnan

Saurabh Khanna

Sachin Bharadwaj, Jr

June Chul Roh

Sachin Bharadwaj

Piyali Goswami

Sachin Bhardwaj

Daniel Colum Breen

Jaiganesh Balakrishnan

Raghu Ganesan

Indu Prathapan

Pankaj Gupta

Peter Aberl

Anand Ganesh Dabak

David A McGrew

Daniel George Wing

Prashanth Patil

K Tirumaleswar Reddy

Sashidharan Venkatraman

Atul Deshpande

Sandeep Kasargod

Jawaharial Tangudu

Krishnakant Vijay Saboo

A frequency-modulated continuous wave (FMCW) radar system is presented. The FMCW radar system includes a receiver configured to receive a radar reflection signal. The radar system further includes an interference detection module, which is configured to identify a portion of the radar reflection signal corresponding to the time period during which the radar reflection signal exceeds a threshold. The FMCW radar system further includes a hysteresis module configured to adjust the identified portion of the radar reflection signal based on the portion of the signal and a hysteresis configuration. The FMCW radar system further includes a mitigation module configured to mitigate interference based on the output of the hysteresis module.

Configurable hysteresis module

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, methods and computer readable mediums are provided for processing radar data to improve detection of weaker targets in the presence of stronger targets. One such system comprises a radar sensor to generate range data based on received radar signals; and a processor that performs a first Doppler Fast Fourier Transform (Doppler-FFT) on the range data to provide a first Doppler-FFT representation, identifies a dominant peak in the first Doppler-FFT representation, determines phase noise associated with the dominant peak, modifies the range data using the determined phase noise to provide modified range data, and performs a second Doppler-FFT on the modified range data to provide a second Doppler-FFT representation. The processor operations may be based on a set of instructions stored on a computer readable medium.

Doppler processing in frequency-modulated continuous wave radar systems using dither

A non-transitory device-readable medium, which may be embodied in a device, such as a radar receiver, stores instructions that, when executed by processing circuitry, are configured to perform operations to identify a region of interference. An analog signal is generated based on received signals reflected from a target object and an interfering object. The analog signal is converted to an initial time-domain data set. Processing circuitry is configured or instructed to perform a transform operation on the initial time-domain data set to generate a frequency-domain data set, based on which a region of interference may be identified. Subsequent operations may be performed to facilitate identification of the region of interest including thresholding, inverse transforming, subtracting, and/or combining. The processing circuitry may be further configured or instructed to generate repaired time-domain data from which corrupted time-domain samples to remove data associated with the interfering object.

Detection of in-band interference

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 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.

Method and system for compression of radar signals

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

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

In an example, a method is implemented in a radar system. The method may include transmitting, via transmission channels, a frame of chirps, the chirps transmitted having a programmed frequency offset that is a function of a transmission channel of the transmission channels that is transmitting the frame of chirps, receiving, via a receive channel, a frame of reflected chirps, the reflected chirps comprising the chirps reflected by an object within a field of view of the radar system, and determining a Doppler domain representation of the frame of reflected chirps having a Doppler domain spectrum that includes multiple spectrum bands, the object represented in at least a portion of the spectrum bands based on the reflected chirps, wherein the programmed frequency is configured to cause the Doppler domain spectrum to include a number of spectrum bands greater than the number of transmission channels.

Empty band doppler division multiple access

A radar system includes a set of transmitters and a processor coupled to the set of transmitters, which includes first, second, third and fourth transmitters. In operation, the processor generates a first chirp of a set of chirps, in which outputs of the first and second transmitters are modulated by a first phase and outputs of the third and fourth transmitters are modulated by a second phase; and generate a second chirp of the set of chirps, in which outputs of the first and fourth transmitters are modulated by the first phase and outputs of the second and third transmitters are modulated by the second phase.

Simultaneous beamforming and multiple input-multiple output (MIMO) schemes in radar system

A method of operating a frequency modulated continuous wave (FMCW) radar system includes receiving, by at least one processor, digital intermediate frequency (IF) signals from a mixer coupled to a receive antenna. The method also includes computing, by the at least one processor, a motion metric based on the digital IF signals; operating, by the at least one processor, the FMCW radar system in a classification mode, in response to determining that the motion metric is above a threshold; and operating, by the at least one processor, the FMCW radar system in a detection mode, in response to determining that the motion metric is below the threshold for at least a first amount of time. An amount of power consumed by the FMCW radar system in the detection mode is less than an amount of power consumed by the FMCW radar system in the classification mode.

FMCW radar reduced power mode

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 method for dithering radar frames includes determining at least one of a chirp period Tc for radar chirps in a radar frame and a chirp slope S for radar chirps in the radar frame. In response to determining the chirp period Tc, a maximum chirp dither Δc(max) is determined, and for the radar frame N, a random chirp dither Δc(N) between negative Δc(max) and positive Δc(max) is determined. In response to determining the chirp slope S, a maximum slope dither Ψ(max) is determined, and for the radar frame N, a random slope dither Ψ(N) between negative Ψ(max) and positive Ψ(max) is determined. A radar sensor circuit generates radar chirps in the radar frame N based on the at least one of (1) the chirp period Tc and the random chirp dither Δc(N) and (2) the chirp slope S and the random slope dither Ψ(N).

Frequency modulated continuous wave radar system with interference mitigation

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.

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Bengaluru, India

Sandeep Rao