Health Monitoring of Tree Trunks Using Ground Penetrating Radar

• Published in: IEEE transactions on geoscience and remote sensing Vol. 57; no. 10; pp. 8317 - 8326
• Main Authors: Giannakis, Iraklis, Tosti, Fabio, Lantini, Livia, Alani, Amir M.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.10.2019; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Antenna arrays; Antenna measurements; Antennas; Approximation; Clutter; Curve fitting; Ground penetrating radar; Ground penetrating radar (GPR); Half spaces; hyperbola fitting; Hyperbolas; Monitoring; Radar; Reflection; Shape; Structural analysis; Tomography; Transforms; tree; trunk; Vegetation
• ISSN: 0196-2892; 1558-0644
• DOI: 10.1109/TGRS.2019.2920224

Ground penetrating radar (GPR) is traditionally applied to smooth surfaces in which the assumption of half-space is an adequate approximation that does not deviate much from reality. Nonetheless, using GPR for internal structure characterization of tree trunks requires measurements on an irregularly shaped closed curve. A typical hyperbola fitting has no physical meaning in this new context since the reflection patterns are strongly associated with the shape of the tree trunk. Instead of a clinical hyperbola, the reflections give rise to complex-shaped patterns that are difficult to be analyzed even in the absence of clutter. In this paper, a novel processing scheme is described which can interpret complex reflection patterns assuming a circular target subject to any arbitrary shaped surface. The proposed methodology can be applied using commercial hand-held antennas in real time, avoiding computationally costly tomographic approaches that require the usage of custom-made bespoke antenna arrays. The validity of the current approach is illustrated both with numerical and real experiments.