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Topographic Change Detection Using Full-Waveform Imaging LidarThe capability of wide-footprint (i.e. 10m or greater), full-waveform laser altimeters to penetrate beneath dense vegetation to directly measure the sub-canopy topography provides us with a unique capability for sensing topographic change in the presence of vegetation. We evaluate the feasibility of using a geolocated laser altimeter return waveform instead of individual elevation measurements to measure vertical elevation change within a laser footprint. The method, dubbed the return pulse correlation method, maximizes the shape similarity of nea-coincident, vertically- geolocated laser return waveforms from two observation epochs as they are vertically-shifted relative to each other. First, we evaluate the inherent accuracy of the pulse correlation method using models and simulations under "bare-Earth" conditions. We then analyze the effects of vegetation and vegetation growth on the change detection capability. The use of this method, combined with order of magnitude improvements to laser altimeter swath widths (from 1 km to 10 km) and the potential for a future spaceborne imaging lidar, may provide subcentimeter level relative change detection beneath vegetation to complement IFSAR's ability to make similar measurements in low or vegetation-free conditions.
Document ID
20020021983
Acquisition Source
Goddard Space Flight Center
Document Type
Conference Paper
Authors
Blair, Bryan
(NASA Goddard Space Flight Center Greenbelt, MD United States)
Hofton, Michele A.
(Maryland Univ. College Park, MD United States)
Smith, David E.
Date Acquired
August 20, 2013
Publication Date
January 1, 2001
Subject Category
Earth Resources And Remote Sensing
Meeting Information
Meeting: 2001 American Geophysical Union Fall Meeting
Location: San Francisco, CA
Country: United States
Start Date: December 10, 2001
End Date: December 14, 2001
Sponsors: American Geophysical Union
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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