A distance measuring device includes a pulsed laser source, a light receiving unit and a computing module. The pulsed laser source emits a laser pulse to a target in accordance with a predetermined period. The light receiving unit has a photon receiving type of light receiving element that receives incident light and outputs a binary pulse, and the binary pulse is used to indicate whether a photon receiving event occurs. The computing module is configured to receive the binary pulse and determine whether an inter-period coincidence event occurs, and the inter-period coincidence event is defined by detecting a plurality of photon receiving events exceeding a predetermined count, on relative positions in a predetermined period number of the predetermined periods. If the calculation module determines that the inter-period coincidence event occurs, a distance of the target is calculated according to time information related to the inter-period coincidence event.

The embodiments described herein provide systems and methods that can improve performance in scanning laser devices. Specifically, the systems and methods utilize a non-uniform variation in optical expansion coupled with variation in the energy level of laser light pulses to provide an improved effective range over a scanning area. In general, the improved effective range varies over the scan field, with relatively long effective range in some areas of the scan field and relatively short effective range in other areas of the scan field. This varying range over the scan field is facilitated by expansion optics that provide a non-uniform variation in optical expansion for laser light pulses relative to position along a first axis in the scan field and by a light source controller that varies the energy level of the laser light pulses according to position along the first axis of the scan field.

Disclosed herein are systems and methods for linearizing frequency chirp in a frequency-modulated continuous wave (FMCW) coherent LiDAR system. Exemplary methods can include generating a continuous wave laser signal having a frequency characteristic, in which the frequency characteristic can include a frequency chirp over a frequency band in at least one period; and receiving a signal based on the generated laser signal. The methods can further include mixing the received signal with a local oscillator signal, the local oscillator signal having the frequency characteristic; determining at least one beat frequency based on the mixed signal; sampling the mixed signal at a rate equal to at least two times the beat frequency; determining a correction signal based on the sampled signal; and applying the correction signal to the laser signal.

Disclosed herein are systems and methods for linearizing frequency chirp in a frequency-modulated continuous wave (FMCW) coherent LiDAR system. Exemplary methods can include generating a continuous wave laser signal having a frequency characteristic, in which the frequency characteristic can include a frequency chirp over a frequency band in at least one period; and receiving a signal based on the generated laser signal. The methods can further include mixing the received signal with a local oscillator signal, the local oscillator signal having the frequency characteristic; determining at least one beat frequency based on the mixed signal; sampling the mixed signal at a rate equal to at least two times the beat frequency; determining a correction signal based on the sampled signal; and applying the correction signal to the laser signal.

Various embodiments of the present technology may provide methods and apparatus for repetitive histogramming. The apparatus may provide a limited number of physical bins to perform multiple histograms on a total number of virtual bins. The apparatus may provide a single physical bin that is used to sweep over the total number of virtual bins.

Various technologies described herein pertain to a time of flight lidar sensor system that uses a coherent detection scheme. The lidar sensor system includes a laser source, a semiconductor optical amplifier, a combiner, and a balanced detector. The laser source emits an input optical signal. The semiconductor optical amplifier receives a first portion of the input optical signal and outputs a modulated optical signal (amplified and modulated). The combiner receives a second portion of the input optical signal and a returned optical signal received responsive to transmission of at least a portion of the modulated optical signal. The combiner coherently mixes the second portion of the input optical signal with the returned optical signal and outputs mixed optical signals. The balanced detector detects the mixed optical signals and generates an output signal (e.g., a differential photocurrent), which can be used to detect a distance to a target.

This application is applicable to the field of radar technologies, and provides a radar data processing method, a terminal device, and a computer-readable storage medium. The method includes: obtaining radar data collected by a receiving area array; if the radar data is saturated, performing data fusion processing based on a floodlight distance value to obtain a fusion result; and determining a distance of a target object based on the fusion result. The method can accurately obtain an actual distance of the target object, effectively reduce a measurement error, improve calculation accuracy, and resolve an existing problem of a large deviation of a measurement result when an actual echo waveform cannot be effectively restored because a signal received by the radar is over-saturated when a laser is directly irradiated on a target object with high reflectivity.

A semiconductor circuitry includes an oscillator configured to output an oscillation signal whose frequency depends on a first input signal, a counter configured to count a number of cycles of the oscillation signal, first circuitry configured to output a first digital signal based on a first number of cycles counted by the counter within one of a clock cycle of a clock signal, wherein the first input signal is digitally converted into the first digital signal, and a second circuitry configured to output a second digital signal based on a second number of cycles counted by the counter in a period from a reference timing of the clock signal to an input timing of a second input signal within the one of the clock cycle of the clock signal, wherein the period is digitally converted into the second digital signal.

A semiconductor circuitry includes an oscillator configured to output an oscillation signal whose frequency depends on a first input signal, a counter configured to count a number of cycles of the oscillation signal, first circuitry configured to output a first digital signal based on a first number of cycles counted by the counter within one of a clock cycle of a clock signal, wherein the first input signal is digitally converted into the first digital signal, and a second circuitry configured to output a second digital signal based on a second number of cycles counted by the counter in a period from a reference timing of the clock signal to an input timing of a second input signal within the one of the clock cycle of the clock signal, wherein the period is digitally converted into the second digital signal.

A method for measuring a distance to a target based upon time modulated polarization state illumination is provided. The method includes: transmitting a time varying polarized light beam toward the target; capturing, at a plurality of subpixel regions of a receiver, a reflected time varying polarized light beam that has been reflected off of the target; generating a plurality of polarization signals for each subpixel region that are indicative of the polarization state of the captured reflected light beam in the subpixel region; calculating a time difference between the transmitted time varying polarized light beam and the captured reflected light beam by comparing the polarization state of the captured reflected light beam with a polarization state of the transmitted time varying polarized light beam; and calculating the distance by multiplying the calculated time difference with the speed of light.