Patent classifications
G01S7/486
Lidar system with integrated frequency shifter for true doppler detection
A vehicle, Lidar system and method of detecting an object is disclosed. The Lidar system includes a photonic chip having a laser, an on-chip frequency shifter, a combiner and a first set of photodetectors. The laser generates a transmitted light beam and an associated local oscillator beam within the photonic chip. The on-chip frequency shifter shifts a frequency of the local oscillator beam. The combiner combines a reflected light beam with the frequency-shifted local oscillator beam, wherein the reflected light beam is a reflection of the transmitted light beam from the object to generate a first electronic signal at the first set of photodetectors. A processor obtains a first measurement of a parameter of the object from the first electronic signal. The vehicle includes a navigation system for navigating the vehicle with respect to the object using at least the first measurement of the parameter.
Lidar system with integrated frequency shifter for true doppler detection
A vehicle, Lidar system and method of detecting an object is disclosed. The Lidar system includes a photonic chip having a laser, an on-chip frequency shifter, a combiner and a first set of photodetectors. The laser generates a transmitted light beam and an associated local oscillator beam within the photonic chip. The on-chip frequency shifter shifts a frequency of the local oscillator beam. The combiner combines a reflected light beam with the frequency-shifted local oscillator beam, wherein the reflected light beam is a reflection of the transmitted light beam from the object to generate a first electronic signal at the first set of photodetectors. A processor obtains a first measurement of a parameter of the object from the first electronic signal. The vehicle includes a navigation system for navigating the vehicle with respect to the object using at least the first measurement of the parameter.
Techniques for automatic gain control in a frequency domain for a signal path for a frequency modulated continuous wave (FMCW) light detection and ranging (LIDAR) system
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.
POSITION REFERENCE SENSOR
A position reference sensor (100) has a light source (120), a detector (160) and a processor (170). The light source (120) is configured to emit light having a first component and a second component. The detector (160) is configured to detect reflected light. The processor (170) is configured to determine a distance between the position reference sensor (100) and a target based on the emitted light and the detected reflected light. The processor (170) is also configured to determine that the target is a selective retroreflector (140) based on the intensity of the first component of the light in the detected reflected light and the intensity of the second component of the light in the detected reflected light.
Method, processing unit and surveying instrument for improved tracking of a target
A method implemented in a processing unit controlling a surveying instrument is provided. The method comprises obtaining a first set of data from optical tracking of a target with the surveying instrument, and identifying from the first set of data a dependence over time of at least one parameter representative of movements of the target. The method further comprises receiving a second set of data from a sensor unit via a communication channel, the second set of data including information about the at least one parameter over time, and determining whether a movement pattern for the optically tracked target as defined by the dependence over time of the at least one parameter is the same as, or deviates by a predetermined interval from, a movement pattern as defined by the dependence over time of the at least one parameter obtained from the second set of data.
Method, processing unit and surveying instrument for improved tracking of a target
A method implemented in a processing unit controlling a surveying instrument is provided. The method comprises obtaining a first set of data from optical tracking of a target with the surveying instrument, and identifying from the first set of data a dependence over time of at least one parameter representative of movements of the target. The method further comprises receiving a second set of data from a sensor unit via a communication channel, the second set of data including information about the at least one parameter over time, and determining whether a movement pattern for the optically tracked target as defined by the dependence over time of the at least one parameter is the same as, or deviates by a predetermined interval from, a movement pattern as defined by the dependence over time of the at least one parameter obtained from the second set of data.
DISTANCE IMAGE ACQUISITION APPARATUS AND DISTANCE IMAGE ACQUISITION METHOD
Disclosed are a distance image acquisition apparatus and a distance image acquisition method capable of achieving high distance measurement accuracy and omitting wasteful imaging or calculation. The distance image acquisition apparatus (10) includes a distance image sensor (14), a drive mode setting unit (20A), a distance image generation unit (20B), a pulse light emission unit (22), and an exposure control unit (24). The exposure control unit (24) controls emission and non-emission of pulse light emitted from the pulse light emission unit (22) according to a drive mode set by the drive mode setting unit (20A), and controls exposure in the distance image sensor (14). The distance image generation unit (20B) performs calculation processing of a sensor output acquired from the distance image sensor (14) according to the drive mode set by the drive mode setting unit (20A) to generate a distance image corresponding to a distance of a subject.
Laser radar device
A laser radar device includes: a modulator (8) for causing a transmission seed light beam to branch, and giving different offset frequencies to a plurality of the transmission seed light beams having branched, and then modulating the plurality of transmission seed light beams into pulsed light beams and outputting the pulsed light beams, or for modulating the transmission seed light beam into a pulsed light beam, causing the pulsed light beam to branch, and giving the different offset frequencies to a plurality of the pulsed light beams having branched, and then outputting the plurality of pulsed light beams; a band pass filter (14) in which a frequency band including frequencies of signal components included in a plurality of beat signals detected by an optical heterodyne receiver (13) is set as a pass band and a frequency band not including the frequencies of the signal components is set as a cutoff band; and an ADC (15) for sampling the beat signals passing through the band pass filter (14) at a sampling frequency.
MEASUREMENT APPARATUS
A measurement apparatus mounted to a vehicle includes a light emitting unit, at least one light receiving element, a measurement unit, a monitor circuit, and an adjustment unit. An adjustment unit adjusts the sensitivity of the at least one light receiving element, based on a monitor signal generated by the monitor circuit based on a light reception signal from the at least one light receiving element having received reference light.
Systems and methods for machine perception
A system to determine a position of one or more objects includes a transmitter to emit a beam of photons to sequentially illuminate regions of one or more objects; multiple cameras that are spaced-apart with each camera having an array of pixels to detect photons; and one or more processor devices that execute stored instructions to perform actions of a method, including: directing the transmitter to sequentially illuminate regions of one or more objects with the beam of photons; for each of the regions, receiving, from the cameras, an array position of each pixel that detected photons of the beam reflected or scattered by the region of the one or more objects; and, for each of the regions detected by the cameras, determining a position of the regions using the received array positions of the pixels that detected the photons of the beam reflected or scattered by that region.