SFCW GPR tree roots detection enhancement by time frequency analysis in tropical areas

TL;DR

This paper enhances GPR-based tree root detection in tropical areas by applying time-frequency analysis to improve noise reduction and signal clarity, enabling more accurate monitoring of tree health.

Contribution

It introduces the use of joint time-frequency analysis with SFCW GPR to improve root detection in high-moisture tropical soils, addressing signal noise issues.

Findings

Improved root detection accuracy in tropical soils.

Effective noise reduction using STFT.

Promising results in controlled and real tests.

Abstract

Accurate monitoring of tree roots using ground penetrating radar (GPR) is very useful in assessing the trees health. In high moisture tropical areas such as Singapore, tree fall due to root rot can cause loss of lives and properties. The tropical complex soil characteristics due to the high moisture content tends to affect penetration depth of the signal. This limits the depth range of the GPR. Typically, a wide band signal is used to increase the penetration depth and to improve the resolution of the GPR. However, this broad band frequency tends to be noisy and selective frequency filtering is required for noise reduction. Therefore, in this paper, we adapt the stepped frequency continuous wave (SFCW) GPR and propose the use of a Joint time frequency analysis (JTFA) method called short time Fourier transform (STFT), to reduce noise and enhance tree root detection. The proposed methodology is illustrated and tested with controlled experiments and real tree roots testing. The results show promising prospects of the method for tree roots detection in tropical areas.