Patent classifications
G01S17/26
SCOUT PULSING
Disclosed herein are system and method embodiments to implement a scout pulse LiDAR. An embodiment operates by emitting a leading sequence of two or more discrete pulses with a constant timing offset and large intensity ratio. These leading pulses are each called a ‘scout pulse’ because they scout ahead of the primary pulse to detect high intensity targets, which would otherwise saturate the detector. In the simplest configuration, there are only two pulses, one primary pulse (lagging, high power/intensity) and one scout pulse (leading, low power/intensity). In more complex configurations, there may be any number of multiple scout pulses, each with a unique time delay and intensity. In any configuration, the signals are emitted in order of ascending intensity, with the lowest intensity signal in front (first), and the highest intensity signal in the back (last) within the pulse train.
SCOUT PULSING
Disclosed herein are system and method embodiments to implement a scout pulse LiDAR. An embodiment operates by emitting a leading sequence of two or more discrete pulses with a constant timing offset and large intensity ratio. These leading pulses are each called a ‘scout pulse’ because they scout ahead of the primary pulse to detect high intensity targets, which would otherwise saturate the detector. In the simplest configuration, there are only two pulses, one primary pulse (lagging, high power/intensity) and one scout pulse (leading, low power/intensity). In more complex configurations, there may be any number of multiple scout pulses, each with a unique time delay and intensity. In any configuration, the signals are emitted in order of ascending intensity, with the lowest intensity signal in front (first), and the highest intensity signal in the back (last) within the pulse train.
Lidar system and method of operation
A lidar system, preferably including one or more transmit modules, beam directors, and/or receive modules, and optionally including one or more processing modules. A method of lidar system operation, preferably including: emitting light beams, receiving reflected light beams, and/or analyzing data associated with the received light beams.
Lidar system and method of operation
A lidar system, preferably including one or more transmit modules, beam directors, and/or receive modules, and optionally including one or more processing modules. A method of lidar system operation, preferably including: emitting light beams, receiving reflected light beams, and/or analyzing data associated with the received light beams.
Method and system for using square wave digital chirp signal for optical chirped range detection
An apparatus is provided for using a square wave digital chirp signal for optical chirp range detection. A laser source emits an optical signal and a RF waveform generator generates an input digital chirp signal based on the square wave digital chirp signal. A frequency of the optical signal is modulated based on the input digital chirp signal. A splitter divides the optical signal into a transmit optical signal and a reference optical signal. A detector combines the reference optical signal and a return optical signal from an object. The detector generates an electrical output signal based on the combined reference optical signal and the return optical signal. A processor determines a range to the object based on a characteristic of a Fourier transform the electrical output signal. A method is also provided for using the square wave digital chirp signal for optical chirp range detection.
Method and system for using square wave digital chirp signal for optical chirped range detection
An apparatus is provided for using a square wave digital chirp signal for optical chirp range detection. A laser source emits an optical signal and a RF waveform generator generates an input digital chirp signal based on the square wave digital chirp signal. A frequency of the optical signal is modulated based on the input digital chirp signal. A splitter divides the optical signal into a transmit optical signal and a reference optical signal. A detector combines the reference optical signal and a return optical signal from an object. The detector generates an electrical output signal based on the combined reference optical signal and the return optical signal. A processor determines a range to the object based on a characteristic of a Fourier transform the electrical output signal. A method is also provided for using the square wave digital chirp signal for optical chirp range detection.
Vehicle sensor fusion
A computer, including a processor and a memory, the memory including instructions to be executed by the processor to obtain velocity lidar point cloud data acquired with a frequency modulated continuous wave (FMCW) lidar sensor, wherein the velocity lidar point cloud data includes a speed with which a data point is moving with respect to the FMCW lidar sensor, filter the velocity lidar point cloud data to select static velocity data points, wherein the static velocity data points are velocity data points each correspond to a point on a roadway around a vehicle. The instructions can include further instructions to determine FMCW lidar sensor accelerations in six degrees of freedom based on the static velocity lidar data points and determine FMCW lidar sensor rotations and translations in six degrees of freedom based on the FMCW lidar sensor accelerations in six degrees of freedom. The instructions can include further instructions to determine vehicle rotations and translations in six degrees of freedom based on inertial measurement unit (IMU) data, determine FMCW lidar sensor mis-alignment based on comparing the FMCW lidar sensor rotations and translations with the vehicle rotations and translations and align the FMCW lidar sensor based on the FMCW lidar sensor mis-alignment. The instructions can include further instructions to operate a vehicle based on the aligned FMCW lidar sensor.
Vehicle sensor fusion
A computer, including a processor and a memory, the memory including instructions to be executed by the processor to obtain velocity lidar point cloud data acquired with a frequency modulated continuous wave (FMCW) lidar sensor, wherein the velocity lidar point cloud data includes a speed with which a data point is moving with respect to the FMCW lidar sensor, filter the velocity lidar point cloud data to select static velocity data points, wherein the static velocity data points are velocity data points each correspond to a point on a roadway around a vehicle. The instructions can include further instructions to determine FMCW lidar sensor accelerations in six degrees of freedom based on the static velocity lidar data points and determine FMCW lidar sensor rotations and translations in six degrees of freedom based on the FMCW lidar sensor accelerations in six degrees of freedom. The instructions can include further instructions to determine vehicle rotations and translations in six degrees of freedom based on inertial measurement unit (IMU) data, determine FMCW lidar sensor mis-alignment based on comparing the FMCW lidar sensor rotations and translations with the vehicle rotations and translations and align the FMCW lidar sensor based on the FMCW lidar sensor mis-alignment. The instructions can include further instructions to operate a vehicle based on the aligned FMCW lidar sensor.
Controlling detection time in photodetectors
Example embodiments relate to controlling detection time in photodetectors. An example embodiment includes a device. The device includes a substrate. The device also includes a photodetector coupled to the substrate. The photodetector is arranged to detect light emitted from a light source that irradiates a top surface of the device. A depth of the substrate is at most 100 times a diffusion length of a minority carrier within the substrate so as to mitigate dark current arising from minority carriers photoexcited in the substrate based on the light emitted from the light source.
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.