Methods and apparatus for increased precision and improved range in a multiple detector LiDAR array
First Claim
1. A light detecting and ranging (LiDAR) system for acquiring information about objects in a scene, the LiDAR system comprising:
- at least one emitter configured to generate emitted radiation within a defined frequency range throughout a field of view of the scene, wherein the emitted radiation is a sequence of N successive pulses with each successive pulse having a same amplitude and duration and a different relative time shift in relation to a sampling time reference signal;
an array of detectors configured to receive reflected radiation within the defined frequency range for the field of view;
circuitry operably coupled to the array of detectors to generate and store digital information corresponding to each detector in the array of detectors, the digital information for each detector in the array of detectors being sampled and stored in a unique one of a set of frame buffers in response to the sampling time reference signal; and
a processing system operably connected to the set of frame buffers and configured to construct a sampled waveform representing the field of view based on the digital information in the set of frame buffers having an effective sampling frequency that is N times a frequency of the sampling time reference signal, and to output at least one parameter based on an analysis of the sampled waveform.
2 Assignments
0 Petitions
Accused Products
Abstract
Methods, systems, and computer program products for acquiring three-dimensional LiDAR information of a scene are disclosed. According to one aspect, acquiring three-dimensional information includes emitting N pulses in a sequence with each successive pulse having a relative time shift to the sampling reference, thus producing a reconstructed sampled signal with an effective sampling rate of N times the sampling reference. According to another aspect, acquiring three-dimensional information includes emitting two or more frequencies, the differences of each pair of differing frequencies being designated as Δf, and sampling the return information with the use of a sampling reference. Frequency analysis is performed on the sampled information to determine the reference times at which the Δf signals occur and the signal intensity of the Δf signals at each time. Systems as described herein can be utilized for autonomous vehicle navigation, collision avoidance and navigation systems for UAVs, roadway surface texture analysis, non-contact friction analysis, and in-motion deflectometer measurement.
-
Citations
20 Claims
-
1. A light detecting and ranging (LiDAR) system for acquiring information about objects in a scene, the LiDAR system comprising:
-
at least one emitter configured to generate emitted radiation within a defined frequency range throughout a field of view of the scene, wherein the emitted radiation is a sequence of N successive pulses with each successive pulse having a same amplitude and duration and a different relative time shift in relation to a sampling time reference signal; an array of detectors configured to receive reflected radiation within the defined frequency range for the field of view; circuitry operably coupled to the array of detectors to generate and store digital information corresponding to each detector in the array of detectors, the digital information for each detector in the array of detectors being sampled and stored in a unique one of a set of frame buffers in response to the sampling time reference signal; and a processing system operably connected to the set of frame buffers and configured to construct a sampled waveform representing the field of view based on the digital information in the set of frame buffers having an effective sampling frequency that is N times a frequency of the sampling time reference signal, and to output at least one parameter based on an analysis of the sampled waveform. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 19)
-
-
18. A light detecting and ranging (LiDAR) system for acquiring information about objects in a scene, the LiDAR system comprising:
-
an array of detectors configured to receive retroreflected radiation within a defined frequency range for a field of view of the scene; circuitry operably coupled to the array of detectors including analog-to-digital (A/D) converters to generate digital data and sampling circuitry to generate a sampling time reference signal; a set of frame buffers operably coupled to the array of detectors and the circuitry to sample and configured to store digital data from each detector in response to the sampling time reference signal as sampled data; a plurality of emitters to generate incident radiation within the defined frequency range throughout the field of view, the incident radiation being generated at two frequencies with overlapping fields of view within the scene, the difference between the frequencies being designated as Δ
f;a processing system configured to perform a frequency analysis on the sampled data to determine sampling times at which Δ
f waveforms are detected and generate at least one parameter based on the frequency analysis.
-
-
20. A method for detecting and identifying an object within a field of view of a scene comprising:
-
providing a LiDAR system, the LiDAR system including an emitter and a detector array; activating the emitter to emit a series of N successive pulses over a field of view for the scene, wherein each successive pulse has a same amplitude and duration and a different relative time shift in relation to a sampling time reference signal; sampling a portion of reflected energy from the emitted light pulses utilizing the detector array at a frequency that is N times the sampling time reference signal and storing the sampled data in a set of frame buffers; using a processing system to construct a sampled waveform representing the field of view based on the data in the set of frame buffers, and analyze sampled waveform to identify and detect an object within the field of view.
-
Specification