Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: A light detection and ranging (LiDAR) core is provided that transmits optical beams, and detects return optical beams. The transmitted optical beams are antiphase chirps that sweep a frequency band, and the sweep of the antiphase chirps includes multiple sub-sweeps over respective sub-bands of the frequency band. The system routes the transmitted optical beams that are launched towards a target, and receives light incident upon the target into the return optical beams. The system simultaneously measures and thereby produces multiple simultaneous measurements of first and second beat frequencies per sweep of the antiphase chirps, from the transmitted and returned optical beams, and includes a simultaneous measurement of the first and second beat frequencies per sub-sweep of the multiple sub-sweeps. And the system determines a range and velocity of the target from the multiple simultaneous measurements of the first and second beat frequencies per sweep of the antiphase chirps.

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 method is provided that transmits a beam of co-propagating, cross-polarized light to a target. The method receives return light reflected from the target, which includes a first polarization and a second polarization. The method splits the return light into a first output corresponding to the first polarization and a second output corresponding to the second polarization using a first beam splitter. The method directs the first output to a first detector and directs the second output to a second detector. The method generates, by the first detector, a first electrical signal corresponding to the first polarization, and generates, by the second detector, a second electrical signal corresponding to the second polarization. The method determines an orientation of the target based on the first electrical signal and the second electrical signal, and generates a point cloud based on the orientation of the target.

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: Free-space optics for use in a light detection and ranging (LIDAR) apparatus include a polarization beam-splitter (PBS) to direct an optical beam in a first direction toward a target environment and to propagate a portion of the optical beam in a second direction for receipt by a photodetector (PD), a polarization wave plate (PWP) to convert the optical beam from a first polarization to a second polarization, and to convert the target return signal from a third polarization to a fourth polarization, and a lens system coupled between the PBS and the PWP to magnify the optical beam. The propagated portion of the optical beam comprises a local oscillator (LO) signal to mix with a target return signal to generate target information.

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) apparatus is provided that includes a dispersive element and an optical circuit. The optical circuit is to emit a first optical beam having a first frequency and a second optical beam having a second frequency towards the dispersive element to deflect the first optical beam and the second optical beam based on a frequency.

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 LiDAR system includes an optical subsystem with an optical axis. The optical subsystem includes an optical source to emit an optical beam, a first optical lens to transmit the optical beam, an optical window to reflect a first portion of the optical beam to generate a LO signal, an optical scanner to transmit a second portion of the optical beam to a target to scan the target to generate a target return signal, a second optical lens to transmit the LO signal and the target return signal to a PD, and the PD to mix the target return signal with the LO signal to extract range and velocity information. The LO signal is disposed to be decentered from the optical axis on the second optical lens to increase a percentage of an overlap of the LO signal and the target return signal on a detection plane of the PD.

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) apparatus includes an optical source to emit an optical beam, and free-space optics coupled with the optical source. The free space optics include a photodetector and other optical components to direct a propagated portion of the optical beam or a reflected portion of the optical beam toward the photodetector as a local oscillator signal, and to transmit the optical beam toward a target environment.

Abstract: A method of operating a light detection and ranging (LIDAR) system is provided that includes generating a beam of co-propagating, cross-polarized light using a first polarizing beam splitter; and determining a material characteristic or orientation of a target using the co-propagating, cross-polarized light.

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: A LIDAR system includes multiple waveguides to receive a return signal at different angles from a scanning mirror, multiple optical detectors to receive the return signal the plurality of waveguides, and a signal processing system operatively coupled to the plurality of optical detectors. The signal processing system is to process a signal generated from each of the optical detectors and combine the processed signals from the different optical detectors into a combined signal, wherein the combined signal is used to determine range and velocity information associated with a target.