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2019 - Cover - Wahyudi Widyatmoko
PUBLIC Devi Septia Nurul



2019 - Paper - Wahyudi Widyatmoko
PUBLIC Devi Septia Nurul

Investigation to determine the Q-factor from transmission Ground-Penetrating Radar (GPR) waves by using the equivalent bandwidth (EBW) method and its applicability is examined through tomographical reconstruction. Q is inversely proportional to the absorption coefficient and describes the material-specific absorption of different rocks. The EBW method is based on the frequency-independent Q and the velocity dispersion after Futterman. We test its applicability to delineate water content distribution in a 30 cm x 30 cm x 30 cm sandstone block from the Elbe Sandstone Mountain, Germany. Synchronous Measurement with a PulseEkko-1000 GPR system and 900 MHz antennas was conducted only from 2 opposite ends of the test object due to physical constraint. The measurements were taken in such a way that from each transmitter position, data is received at all receivers. Due to the small test object, it is impossible to complete record full 5-phase transmission signals. Despite this constraint, practical analysis of using shortened transmission signal still provide a good Q estimate. Our results conclude that calculated velocity values from the tomography measurement data show a significant velocity decrease with increasing position, which correlates with the increasing water content and the higher the Q value the smaller the water content value