Development effort of the airborne lidar simulator for the lidar surface topography (LIST) mission

Yu, Anthony W.; Krainak, Michael A.; Harding, David J.; Abshire, James B.; Sun, Xiaoli; Cavanaugh, John F.; Valett, Susan; Ramos-Izquierdo, Luis; Winkert, Tom; Kirchner, Cynthia; Plants, Michael; Filemyr, Timothy; Kamamia, Brian; Hasselbrack, William; Dogoda, Peter

doi:10.1117/12.898545

Cited by 8 publications

(13 citation statements)

References 2 publications

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“…Another example of a high sensitivity multiple gain stage detector is the intensified photodiode (IPD) that uses a hybrid photomultiplier tube with a transfer electron (TE) InGaAsP photocathode to convert incident photons into electrons and then a backend GaAs avalanche photodiode to provide a two stage electron gain factor of about 10,000 with reported 25% photon detection efficiency [6]. This so-called hybrid photomultiplier tube (HPMT) boasts photon counting performance and high maximum count rate that reaches 100 Mcts/s with the possibility of using an APD anode array backend to create a multi-element detector [9]. A different approach to attaining single-photon sensitivity is through novel materials engineering as described by Bailey et al in reference [10].…”

Section: Types Of 3d Flash Ladar Camerasmentioning

confidence: 99%

Real-time 3D flash ladar imaging through GPU data processing

et al. 2011

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We present real-time 3D image processing of flash ladar data using our recently developed GPU parallel processing kernels. Our laboratory and airborne experiences with flash ladar focal planes have shown that per laser flash, typically only a small fraction of the pixels on the focal plane array actually produces a meaningful range signal. Therefore, to optimize overall data processing speed, the large quantity of uninformative data are filtered out and removed from the data stream prior to the mathematically intensive point cloud transformation processing. This front-end pre-processing, which largely consists of control flow instructions, is specific to the particular type of flash ladar focal plane array being used and is performed by the computer's CPU. The valid signals along with their corresponding inertial and navigation metadata are then transferred to a GPU device to perform range-correction, geo-location, and ortho-rectification on each 3D data point so that data from multiple frames can be properly tiled together either to create a wide-area map or to reconstruct an object from multiple look angles. GPU parallel processing kernels were developed using OpenCL. Postprocessing to perform fine registration between data frames via complex iterative steps also benefits greatly from this type of high-performance computing. The performance improvements obtained using GPU processing to create corrected 3D images and for frame-to-frame fine-registration are presented.

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Section: Types Of 3d Flash Ladar Camerasmentioning

confidence: 99%

Real-time 3D flash ladar imaging through GPU data processing

et al. 2011

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“…The total output laser power would be 1 kW (1000 times 100 μJ pulsing at 10 kHz [34]), more than 80 times the output power of the current most powerful spaceborne lidar. This would be a demanding engineering task, even if laser efficiencies were raised from the current in-orbit limit of 5-8% [35,36] to the proposed 15% [34] and would require 6.7 kW of power for the instrument (doubling to 13.4 kW to account for heat dissipation). Furthermore, few details have been made public since the description of the airborne simulator [34] was published in 2010.…”

Section: Existing Spaceborne Lidarsmentioning

confidence: 99%

Requirements for a global lidar system: spaceborne lidar with wall-to-wall coverage

et al. 2021

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Lidar is the optimum technology for measuring bare-Earth elevation beneath, and the structure of, vegetation. Consequently, airborne laser scanning (ALS) is widely employed for use in a range of applications. However, ALS is not available globally nor frequently updated due to its high cost per unit area. Spaceborne lidar can map globally but energy requirements limit existing spaceborne lidars to sparse sampling missions, unsuitable for many common ALS applications. This paper derives the equations to calculate the coverage a lidar satellite could achieve for a given set of characteristics (released open-source), then uses a cloud map to determine the number of satellites needed to achieve continuous, global coverage within a certain time-frame. Using the characteristics of existing in-orbit technology, a single lidar satellite could have a continuous swath width of 300 m when producing a 30 m resolution map. Consequently, 12 satellites would be needed to produce a continuous map every 5 years, increasing to 418 satellites for 5 m resolution. Building 12 of the currently in-orbit lidar systems is likely to be prohibitively expensive and so the potential of technological developments to lower the cost of a global lidar system (GLS) are discussed. Once these technologies achieve a sufficient readiness level, a GLS could be cost-effectively realized.

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“…The most difficult requirement is to reliably detect the ground height beneath dense, closed-canopy forest cover, for which a lidar with high dynamic range is essential. In order to meet these requirements we have formulated a highly efficient lidar measurement approach utilizing 1,000 push-broom, micropulse laser beams coupled with a photon-sensitive, linear-mode detector array [5]. This paper addresses the progress we have made toward technology advancement of a suitable, high-efficiency laser transmitter.…”

Section: Introductionmentioning

confidence: 99%