Abstract: Embodiments of the present disclosure relate generally to terrain mapping, and more particularly to a method and system for maintaining a normalized view of a terrain during an airborne data collection process. Embodiments include an intelligent sensing methodology that, on a near-real time basis, continually monitors the geometry and instantaneous height of the immediate region (voxel) under collection by an airborne sensor, thus maintaining complete, continual situational awareness of the topography under investigation. In this manner, swath asymmetries and occlusions resulting from pronounced elevation peaks can be fully assessed, quantified, and remedied at the terminus of and/or during each scan. In some embodiments, this is done by adjusting the platform's collection system scan parameters (e.g. by adjusting a scan angle for the affected direction) on a scan-by-scan basis to eliminate such asymmetries and occlusions from each collection swath.

Abstract: Light detection and ranging (lidar) technology is capable of using light to measure the distance to objects in a field of view. A lidar system typically comprises a lidar transmitter, a lidar receiver, and a clock. The lidar transmitter transmits light into the field of view, and the light is reflected back to the lidar receiver after striking objects in the field of view. Techniques are described herein for encoding channel information into light transmissions so that the lidar receiver can use the encoded channel information to reduce the out-of-channel noise in channel-specific photodetection signals.

Abstract: The present disclosure relates to calibration of actively illuminated low fill-factor sensor devices and object detection, including capturing one or more returns in a first scan direction, assigning first timestamps corresponding to one or more of the returns in the first scan direction, identifying one or more peaks corresponding to intensity of one or more of the returns, correlating peak timestamps with one or more time intervals, the peak timestamps being associated with the peaks, generating a scan timing interval based on the peak timestamps, and calibrating one or more input devices or output devices based on the scan timing interval.

Abstract: The present disclosure relates to calibration of actively illuminated low fill-factor sensor devices and object detection, including capturing one or more returns in a first scan direction, assigning first timestamps corresponding to one or more of the returns in the first scan direction, identifying one or more peaks corresponding to intensity of one or more of the returns, correlating peak timestamps with one or more time intervals, the peak timestamps being associated with the peaks, generating a scan timing interval based on the peak timestamps, and calibrating one or more input devices or output devices based on the scan timing interval.

Abstract: Disclosed herein are examples of ladar systems and methods where data about a plurality of ladar returns from prior ladar pulse shots gets stored in a spatial index that associates ladar return data with corresponding locations in a coordinate space to which the ladar return data pertain. This spatial index can then be accessed by a processor to retrieve ladar return data for locations in the coordinate space that are near a range point to be targeted by the ladar system with a new ladar pulse shot. This nearby prior ladar return data can then be analyzed by the ladar system to help define a parameter value for use by the ladar system with respect to the new ladar pulse shot. Examples of such adaptively controlled parameter values can include shot energy, receiver parameters, shot selection, camera settings, and others.

Abstract: A ladar system capable of operating in a ladar mode and an optical communication mode is disclosed. When operating in the ladar mode, a ladar transmitter and ladar receiver cooperate to transmit ladar pulses that are used for ranging to targets in a field of view. When operating in an optical communication mode, ladar pulses are used to transmit data messages to locations in the field of view that are determined to have devices that are capable of receiving the optically communicated data messages.

Abstract: Systems and methods can employ an emitter with adaptive active illumination in combination with a receiver that images a field of view illuminated by the emitter.

Abstract: Disclosed herein is a compact beam scanner assembly that includes an ellipsoidal reimaging mirror.

Abstract: A lidar system that includes a laser source and a scannable mirror can also include a circuit that schedules a variable rate firing of a plurality of upcoming laser pulse shots by the laser source using a laser energy model as compared to a plurality of energy requirements applicable to the upcoming laser pulse shots, and wherein the laser energy model takes into consideration a retention of energy in the laser source after the upcoming laser pulse shots are fired and quantitatively predicts available energy amounts for the upcoming laser pulse shots from the laser source based on a history of prior laser pulse shots by the laser source. The laser energy model is capable of modeling the energy available for laser pulse shots in the laser source over very short time intervals (such as 10-100 nanoseconds).

Abstract: Disclosed herein are a number of example embodiments that employ controllable delays between successive ladar pulses in order to discriminate between “own” ladar pulse reflections and “interfering” ladar pulses reflections by a receiver. Example embodiments include designs where a sparse delay sum circuit is used at the receiver and where a funnel filter is used at the receiver. Also, disclosed are techniques for selecting codes to use for the controllable delays as well as techniques for identifying and tracking interfering ladar pulses and their corresponding delay codes. The use of a ladar system with pulse deconfliction is also disclosed as part of an optical data communication system.

Abstract: Ladar System with Intelligent Selection of Shot Patterns Based on Field of View Data A ladar transmitter that transmits ladar pulses toward a plurality of range points in a field of view can be controlled to target range points based on any of a plurality of defined shot patterns. Each defined shot pattern can be instantiated to identify various coordinates in the field of view that are to be targeted by a ladar pulses. A processor can process data about the field of view such as range data and/or camera data to make selections as to which of the defined shot patterns should be selected over time.

Abstract: A lidar system comprises (1) an array of pixels for sensing incident light and (2) a circuit for processing a signal representative of the sensed incident light to detect a reflection of a laser pulse from a target within a field of view. The circuit can comprise a plurality of matched filters that are tuned to different reflected pulse shapes for detecting pulse reflections within the incident light, and wherein the circuit (1) applies the signal to the matched filters to determine an obliquity for the target based how the matched filters respond to the applied signal and (2) determines a correction angle based on the determined target obliquity, the correction angle for orienting the field of view to a frame of reference in response to a tilting of the lidar system. In an example embodiment, the circuit can comprise a signal processing circuit that performs the signal application and correction angle determination operations.

Abstract: Disclosed herein are examples of ladar systems and methods where data about a plurality of ladar returns from prior ladar pulse shots gets stored in a spatial index that associates ladar return data with corresponding locations in a coordinate space to which the ladar return data pertain. This spatial index can then be accessed by a processor to retrieve ladar return data for locations in the coordinate space that are near a range point to be targeted by the ladar system with a new ladar pulse shot. This nearby prior ladar return data can then be analyzed by the ladar system to help define a control parameter for use by the ladar receiver with respect to the new ladar pulse shot.

Abstract: Disclosed herein is a compact beam scanner assembly that includes an ellipsoidal reimaging mirror.

Abstract: Disclosed herein are various embodiments of an adaptive ladar receiver and associated method whereby the active pixels in a photodetector array used for reception of ladar pulse returns can be adaptively controlled based at least in part on where the ladar pulses were targeted. Additional embodiments disclose improved imaging optics for use by the receiver and further adaptive control techniques for selecting which pixels of the photodetector array are used for sensing incident light.

Abstract: A lidar system having a lidar transmitter and lidar receiver that are in a bistatic arrangement with each other can be deployed in a climate-controlled compartment of a vehicle to reduce the exposure of the lidar system to harsher elements so it can operate in more advantageous environments with regards to factors such as temperature, moisture, etc. In an example embodiment, the bistatic lidar system can be connected to or incorporated within a rear view mirror assembly of a vehicle.

Abstract: A lidar receiver that includes a photodetector circuit can be controlled so that the detection intervals used by the lidar receiver to detect returns from fired laser pulse shots are closely controlled. Such control over the detection intervals used by the lidar receiver allows for close coordination between a lidar transmitter and the lidar receiver where the lidar receiver is able to adapt to variable shot intervals of the lidar transmitter (including periods of high rate firing as well as periods of low rate firing). The lidar receiver can define the detection intervals based on a region in the field of view that a laser pulse shot is targeting (e.g., setting longer detection intervals for laser pulse shots targeting a horizon region, setting shorter detection intervals for laser pulse shots targeting a region that intersects within the ground within a relatively short distance of the lidar system).

Abstract: A lidar system that includes a laser source can be controlled to schedule the firing of laser pulse shots at range points in a field of view. As part of this scheduling, the system can prioritize which elevations will be targeted with shots before other elevations based on defined criteria. Examples of such criteria can include prioritizing elevations corresponding to a horizon, prioritizing elevations which contain objects of interest (e.g., nearby objects, fast moving objects, objects heading toward the lidar system, etc).

Abstract: A lidar system comprises a lidar transmitter and a control circuit. The lidar transmitter fires laser pulse shots into a field of view and comprises a variable amplitude scan mirror for directing the laser pulse shots at targeted range points in the field of view (FOV). The control circuit (1) controls changes in a tilt amplitude of the variable amplitude scan mirror and (2) schedules the laser pulse shots according to a plurality of criteria, including criteria that take into account a settle time arising from controlled changes in the tilt amplitude. These controlled changes can include (1) a first tilt amplitude corresponding to a wide FOV coverage zone within the FOV and (2) a second tilt amplitude corresponding to a narrow FOV coverage zone within the FOV, wherein the second tilt amplitude is less than the first tilt amplitude.

Abstract: A lidar system that includes a laser source and transmits laser pulses produced by the laser source toward range points in a field of view via a mirror that scans through a plurality of scan angles can use (1) a laser energy model to model the available energy in the laser source over time and (2) a mirror motion model to model motion of the mirror over time. A shot list for the upcoming laser pulse shots that are modeled according to the laser energy and mirror motion models can further be controlled based on eye safety and/or camera safety models to prevent the lidar system firing too much laser energy into defined spatial areas over defined time periods and thus reduce the risk of damage to eyes and/or cameras in the field of view.