Digital Terrain Model Retrieval in Tropical Forests Through P-Band SAR Tomography

This paper focuses on the retrieval of terrain topography below dense tropical forests by means of synthetic aperture radar (SAR) systems. Low-frequency signals are needed to penetrate such a thick vegetation layer; however, this expedient alone does not guarantee proper retrieval. It is, here, demo...

Full description

Saved in:
Bibliographic Details
Published in:IEEE transactions on geoscience and remote sensing 2019-09, Vol.57 (9), p.6774-6781
Main Authors: Mariotti D'Alessandro, Mauro, Tebaldini, Stefano
Format: Article
Language:English
Subjects:
Backscattering
Detection
Digital elevation models
Digital terrain model (DTM)
forest
Forestry
Forests
ground
Height
Image resolution
Incidence angle
Laser radar
Lidar
mapping
Measuring instruments
Model accuracy
Radar
Retrieval
SAR (radar)
Synthetic aperture radar
synthetic aperture radar (SAR)
Terrain models
Tomography
Topography
Topography (geology)
tropical
Tropical climate
Tropical forests
Vegetation mapping
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:This paper focuses on the retrieval of terrain topography below dense tropical forests by means of synthetic aperture radar (SAR) systems. Low-frequency signals are needed to penetrate such a thick vegetation layer; however, this expedient alone does not guarantee proper retrieval. It is, here, demonstrated that the phase center of P-band backscatter may lie several meters above the ground, depending on the slope and incidence angle. SAR tomography is shown to overcome this problem and retrieves the actual topography even in the presence of dense trees up to 50 m tall. Digital terrain models returned by SAR tomography are, here, put in comparison with light detection and ranging (LiDAR) terrain models: the accuracy of radar-derived maps is found to be at least comparable with the one offered by LiDAR systems. Moreover, the discrepancy between tomography and LiDAR is larger if large-footprint LiDAR is considered thus suggesting that, in this case, tomographic maps should be considered the reference height. Analyses are carried out by processing three data sets gathered over different tropical forests in western Africa. The robustness of the radar estimates is assessed with respect to both ground slope and treetop height.
ISSN:0196-2892
1558-0644
DOI:10.1109/TGRS.2019.2908517