GPR and reflection seismics share common physical and methodological bases but are sensitive to different subsurface physical properties. The peculiarities of the electromagnetic case impact data acquisition, processing and interpretation. We review multi-offset techniques in GPR applications focusing on similarities and differences through examples taken from different subsurface and target co...

Passive wireless transducers are used as sensors, probed by a RADAR system. A simple way to separate the returning signal from the clutter is to delay the response, so that the clutter decays before the echoes are received. This can be achieved by introducing a fixed delay in the sensor design. Acoustic wave transducers are ideally suited as cooperative targets for passive, wireless sensing. Th...

A sliding window based prescreening algorithm, utilizing multi-scale histogram of oriented gradient (MS-HOG) features and a linear support vector machine (SVM) classifier, for detection of buried explosive hazards in forwardlooking infrared (FL-IR) and forward-looking ground penetrating radar (FL-GPR) data is presented. This algorithm is compared to previously published FL-IR and FL-GPR prescre...

ground penetrating radar (gpr) method as a high resolution non-destructive geophysical method is used for detection of shallow subsurface targets. this method is based on the transmission of electromagnetic waves inside the earth and recording the reflected waves from the subsurface. as the method uses high-frequency electromagnetic waves in the frequency ranges of 12.5 to 2500 mhz (called gpr ...

Ground-penetrating radar (GPR) data affected by waveguide dispersion are not straightforward to analyse. Therefore, waveguide dispersed common midpoint measurements are typically interpreted using so-called dispersion curves, which describe the phase velocity as a function of frequency. These dispersion curves are typically evaluated with deterministic optimization algorithms that derive the di...

It is well known in B-scan ground penetrating radar (GPR) imagery that the underground scatterers generally exhibit defocused, hyperbolic characteristics. This is mainly due to the data collection scheme and the finite beam width of the main lobe of the GPR antenna. To invert this undesirable effect and obtain focused images, various migration or focusing algorithms have been developed. In this...

In recent years, the ground penetrating radar (GPR) is increasingly used in the detection of riprap embankments. In order to analyze the costal embankment with explosive compaction, model experiments are conducted to investigate the influence of seawater on the signal and image of GPR, especially to figure out the image variation of riprap bottom boundary. The influence of immersion of seawater...

Ground penetrating radar (GPR) was used to characterize the frequency-dependent dielectric relaxation phenomena in ordinary Portland cement (OPC) hydration in concrete changing from fresh to hardened state. The study was experimented by measuring the changes of GPR A-scan waveforms over a period of 90 days, and processed the waveforms with short-time Fourier transform (STFT) in joint time-frequ...

High-resolution tomographic images obtained from crosshole geophysical measurements have the potential to provide valuable information about the geostatistical properties of unsaturated-zone hydrologic-state variables such as moisture content. Under drained or quasi-steady-state conditions, the moisture content will reflect the variation of the physical properties of the subsurface, which deter...

Geophysical methods are important tools for a wide range of geological, hydrogeological, and engineering investigations. Conventional processing techniques for electromagnetic tools often use approximations that may be either inappropriate or only provide limited resolution. Higher resolution images can be derived by using more sophisticated approaches that explicitly take into account the elec...