HR: 08:15h
AN: G11B-02    [Abstracts]
TI: Implementation of Waveform Digitization In A Small Footprint, Airborne Lidar Topographic Mapping System
AU: * Gutierrez, R
EM: oskar@mail.utexas.edu
AF: Bureau of Economic Geology, The University of Texas at Austin, 10100 Burnet Road, Bldg 130, Austin, TX 78758-4445 United States
AU: Crawford, M M
EM: crawford@csr.utexas.edu
AF: Center for Space Research, The University of Texas at Austin, 3925 West Braker Lane, Suite 200, Texas, TX 78759-5321 United States
AU: Liadsky, J
EM: joe@optech.on.ca
AF: Optech, Incorporated, 100 Wildcat Road, Toronto, ONT M3J 2Z9 Canada
AB: Accurate mapping is critical for applications ranging from geodesy, geomorphology, and forestry to urban planning and natural hazards monitoring. While airborne lidar (Light Detection and Ranging) has had a revolutionary impact on three-dimensional imaging of the earth's surface, there is great potential for developing new capability by replacing the laser range and backscatter intensity information recorded by conventional lidar systems with full waveform digitization. The University of Texas at Austin (UT) owns and operates an Optech ALTM 1225, a small footprint lidar system. In response to an initiative from UT, Optech has developed a module which samples the analog waveform of a laser pulse and converts these samples into digital measurements. The waveform digitizer specifications include a 1-nanosecond sampling interval, 440 samples per return laser waveform (approximately 65 meters of vertical extent), and waveform digitization at the 25kHz laser pulse repetition rate. The digitizer also records the initial T0 pulse that starts the timing cycle. The digitizer unit is an independent module supported by a Pentium-4 computer, two hard drives, and a high-speed data recording system. The digitizer is integrated into the ALTM system so that both full waveform and the conventional first and last returns are recorded for each transmitted laser pulse. This unique capability allows for conventional lidar data to be directly compared to the full waveform. We present examples of full waveform lidar mapping over different environments and discuss future applications.
DE: 8040 Remote sensing
DE: 8107 Continental neotectonics
DE: 1815 Erosion and sedimentation
DE: 1824 Geomorphology (1625)
DE: 1294 Instruments and techniques
SC: Geodesy [G]
MN: 2004 AGU Fall Meeting