Abstract: A method including receiving, responsive to a transmission of a plurality of optical beams into an environment including a target, a plurality of returned optical beams associated with the target. The method includes generating a plurality of points from the plurality of returned optical beams, wherein each one of the plurality of points respectively corresponds to one of the plurality of returned optical beams; selecting a first point from the plurality of points and a second point from the plurality of points. The method includes identifying, by a processor, an orientation of the first point relative to the FMCW LIDAR system based on the second point from the plurality of points. The method includes computing an orientation of the target relative to the FMCW LIDAR system based on the orientation of the first point; and generating a point cloud based on the orientation of the target.

Abstract: A method of compensation in a light detection and ranging (LIDAR) system. The method includes applying a first frequency shift to a target signal to compensate for doppler shift in the target signal and performing a phase impairment correction on the target signal to produce a corrected target signal. The method further includes undoing the first frequency shift on the corrected target signal.

Abstract: The LiDAR system includes a coherent receiver disposed in a reference path. The coherent receiver includes a 90° optical hybrid to receive a portion of an optical beam along the reference path and a local oscillator (LO) signal to generate multiple output signals. The coherent receiver includes a first photodetector to receive a first and a second output signal to generate a first mixed signal, and a second photodetector to receive a third and a fourth output signal to generate a second mixed signal. The LiDAR system further includes a processor to combine the first mixed signal and the second mixed signal to generate a combined reference signal to suppress a negative image of a reference beat frequency signal to estimate a phase noise of the optical source to determine range and velocity information of the target.

Abstract: A light detection and ranging (LIDAR) system to transmit optical beams including at least up-chirp frequency and at least one down-chirp frequency toward targets in a field of view of the LIDAR system and receive returned signals of the up-chirp and the down-chirp as reflected from the targets. The LIDAR system may determine multiple frequency peaks associated with the target based on the returned signals. Upon determining that at least one of the multiple frequency peaks is within one or more sets of frequency ranges, the LIDAR system may combine an in-phase signal and a quadrature signal of the returned signals to generate a complex signal that enables determining whether the at least one of the multiple frequency peaks is associated with ghosting. Upon determining to be free from ghosting, the LIDAR system determines one or more of the target location, a target velocity, and a target reflectivity.

Abstract: Techniques for cascade filtering of a set of points of interest (POIs) in a light detection and ranging (LiDAR) system is described. The method includes performing a series of cascaded filtering of a set of points of interest (POIs) on a first point cloud. The method includes calculating, for each POI of the set of POIs, at least a first metric for a first set of neighborhood points to make a decision with respect to a subset of the set of POIs for transmission to a second point cloud. The method also includes extracting at least one of range or velocity information based on the second point cloud based on the decision.

Abstract: A set of POIs of a point cloud are received at a first filter, where each POI of the set of POIs comprises one or more points. Each POI of the set of POIs is filtered. A set of neighborhood points of a POI is selected. A metric for the set of neighborhood points is computed. Based on the metric, whether to accept the POI, modify the POI, reject the POI, or transmit the POI to a second filter, to extract at least one of range or velocity information related to the target is determined. Provided the POI is accepted or modified, the POI is transmitted to a filtered point cloud; provided the POI is rejected, the POI is prevented from reaching the filtered point cloud; provided the POI is not accepted, modified, or rejected, the POI is transmitted to a second filter.

Abstract: A light detection and ranging (LIDAR) system to transmit optical beams including at least two up-chirp signals and at least two down-chirp signals toward targets in a field of view of the LIDAR system and receive returned signals of the up-chirp and the down-chirp as reflected from the targets. The LIDAR system generates a baseband signal in a frequency domain of the returned signals of the at least two up-chirp signals and the at least two down-chirp signals. The baseband signal includes a first set of peaks associated with the at least one up-chirp signal and a second set of peaks associated with the at least one down-chirp signal. The LIDAR system determines the target location using the first set of peaks and the second set of peaks.

Abstract: A light detection and ranging (LIDAR) system has a modulator to modulate a light signal from an optical source with a low-power mode at a section of a sweep signal to generate a pulsed light signal transmitted towards a target. The LIDAR system has a photodetector to receive a return beam from the target with an amplitude modulated (AM) signal portion and a frequency modulated (FM) signal portion. The LIDAR system processes the return beam with in-phase/quadrature (I/Q) detection to extract the AM signal portion and the FM signal portion. The system determines a range value and a velocity value for the target based on the extracted AM signal portion and the extracted FM signal portion.

Abstract: A method of compensation in a light detection and ranging (LIDAR) system. The method includes generating a digitally-sampled target signal. The method also includes compensating for ego-velocity and target velocity in the digitally-sampled target signal based on an estimated ego-velocity and an estimated target velocity to produce a compensated digitally-sampled target signal.

Abstract: A frequency modulated continuous wave (FMCW) light detection and ranging (LIDAR) system includes an automatic gain control (AGC) unit to reduce the dynamic range of the signal to be processed. The system detects a return beam of a light signal transmitted to a target, having a first dynamic range in a time domain. The AGC unit can measure a power of the return beam, and apply variable gain in the time domain to reduce a dynamic range of the return beam to a lower dynamic. An analog to digital converter (ADC) generates a digital signal based on the return beam. A processor can perform time domain processing on the digital signal, convert the digital signal from the time domain to a frequency domain, and perform frequency domain processing on the digital signal in the frequency domain.

Abstract: A light detection and ranging (LIDAR) system includes an automatic gain control (AGC) unit to reduce the dynamic range, reducing processing power and saving circuit area and cost. The system detects a return beam of a light signal transmitted to a target, having a first dynamic range in a time domain. An analog to digital converter (ADC) generates a digital signal based on the return beam. A processor can perform time domain processing on the digital signal, convert the digital signal from the time domain to a frequency domain, and perform frequency domain processing on the digital signal in the frequency domain. The AGC unit can measure a power of the return beam, and apply variable gain in the frequency domain to reduce a dynamic range of the return beam to a second dynamic range lower than the first dynamic range.

Abstract: A light detection and ranging (LIDAR) system includes an automatic gain control (AGC) unit to reduce the dynamic range, reducing processing power and saving circuit area and cost. The system detects a return beam of a light signal transmitted to a target, having a first dynamic range in a time domain. An analog to digital converter (ADC) generates a digital signal based on the return beam. A processor can perform time domain processing on the digital signal, convert the digital signal from the time domain to a frequency domain, and perform frequency domain processing on the digital signal in the frequency domain. The AGC unit can measure a power of the return beam, and apply variable gain in the frequency domain to reduce a dynamic range of the return beam to a second dynamic range lower than the first dynamic range.

Abstract: A light detection and ranging (LIDAR) system has an active modulator to modulate a light signal from an optical source with a low-power mode at a section of a sweep signal to generate a pulsed light signal transmitted towards a target. The LIDAR system has a photodetector to receive a return beam from the target with an amplitude modulated (AM) signal portion and a frequency modulated (FM) signal portion. The LIDAR system determines a target range value for the target based on the AM signal portion and determines a target velocity value for the target based on the FM signal portion.

Abstract: A light detection and ranging (LIDAR) system performs a method including generating a frequency domain waveform based on a baseband signal in a time domain, determining a first likelihood metric for frequencies in the frequency domain waveform, and identifying one or more frequencies in the frequency domain waveform that exceed a threshold value for the first likelihood metric. The method further includes determining a second likelihood metric for the frequencies in the frequency domain waveform, selecting a peak frequency from the frequency domain waveform corresponding to the frequency with the highest value for the second likelihood metric based on the one or more frequencies in the frequency domain waveform that exceed the threshold value for the first likelihood metric, and determining one or more properties of a target based at least in part on the selected peak frequency and the corresponding values of the first and second likelihood metrics.

Abstract: A light detection and ranging (LIDAR) system performs a method including generating a frequency domain waveform based on a baseband electrical signal in a time domain, wherein the frequency domain waveform includes a spectrum of frequencies, separating the spectrum of frequencies in the frequency domain waveform into multiple frequency bands including at least a first frequency band and a second frequency band, and performing a first peak detection within the first frequency band. The method further includes performing a second peak detection within the second frequency band, wherein the first peak detection and second peak detection are different peak detection techniques, and selecting a peak frequency from the spectrum of frequencies in the frequency domain waveform based at least in part on the first peak detection within the first frequency band and the second peak detection within the second frequency band.

Abstract: A light detection and ranging (LIDAR) system performs a method including generating a frequency domain waveform based on a baseband electrical signal in a time domain, wherein the frequency domain waveform includes a spectrum of frequencies and determining a likelihood metric for the spectrum of frequencies of the frequency domain waveform. The method further includes in response to one or more parameters associated with the frequency domain waveform satisfying a condition, modifying the likelihood metric for the spectrum of frequencies based on the one or more parameters associated with the frequency domain waveform to generate a modified likelihood metric for the spectrum of frequencies, selecting a peak frequency from the frequency domain waveform corresponding to a frequency with the highest value for the modified likelihood metric, and determining one or more properties of a target based at least in part on the selected peak frequency.

Abstract: A light detection and ranging (LIDAR) system to transmit optical beams including at least up-chirp frequency and at least one down-chirp frequency toward targets in a field of view of the LIDAR system and receive returned signals of the up-chirp and the down-chirp as reflected from the targets. The LIDAR system may perform IQ processing on one or more returned signals to generate baseband signals in the frequency domain of the returned signals during the at least one up-chirp and the at least one down-chirp. The baseband signal includes a first set of peaks associated with the at least one up-chirp frequency and a second set of peaks associated with the at least one down-chirp frequency. The LIDAR system determines the target location using the first set of peaks and the second set of peaks.

Abstract: A light detection and ranging (LIDAR) system has a passive modulator to modulate a light signal from an optical source with a low-power mode at a section of a sweep signal to generate a pulsed light signal transmitted towards a target. The LIDAR system has a photodetector to receive a return beam from the target with an amplitude modulated (AM) signal portion and a frequency modulated (FM) signal portion. The LIDAR system determines a target range value for the target based on the AM signal portion and determines a target velocity value for the target based on the FM signal portion.

Abstract: Techniques for cascade filtering of a set of points of interest (POIs) in a light detection and ranging (LiDAR) system is described. The method includes performing a series of cascaded filtering of a set of points of interest (POIs) in a first point cloud and a second point cloud of the LiDAR system. The method also includes calculating at least a first metric over at least the POI and to make a decision with respect to the second point cloud, and extracting at least one of range and velocity information based on the second point cloud.

Abstract: A light detection and ranging (LIDAR) system encodes a frequency modulation (FM) modulated signal with a time of flight (TOF) signal as a power and frequency modulated signal. The system can emit the power and frequency modulated signal and apply processing to a signal reflection to generate a target point set. The target point set processing can include frequency processing to generate target points based on range and Doppler information, and TOF processing to provide TOF range information. The processing can include an FM processing path to extract FM signal information, and an AM processing path to extract the TOF signal information.