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We apply an automated picking and inversion algorithm to ground-based and airborne glaciological GPR surveys, in order to recover the internal stratigraphy, density distribution, and water content of alpine glaciers. Current glacier monitoring techniques encompass topographic mapping, direct measurements, and GPR surveys. However, the resulting models strongly depend on the assumptions made about...
Ground Penetrating Radar (GPR) investigations were conducted in order to characterize the reflection patterns and internal architecture of Vistula River point bars. The study area is situated in the south part of Warsaw (Central Poland), in the Nature Reserve Świderskie Islands, where fluvial deposits were well accessible due to an unusually low water level in the Vistula River. Ground Penetrating...
Several data fusion approaches have been developed to maximize both resolution and characterization depth for GPR. In this study, we propose a new physically-based method to merge multi-frequency radar data coming from different antennas. The strategy relies on the removal of antenna effects and the subsequent fusion of the resulting Green's functions in the frequency domain. We validated the approach...
A GPR system is composed of a transmitter and a receiver antenna placed on the ground surface. The exciting current injected into the transmitter antenna is, in general, unknown. Its knowledge is of great importance in the GPR modeling in time or frequency. In the following analysis we, firstly, identify different types of GPR waves for two parallel dipole antennas located on the ground in a common...
Much work, some quite complex, has been expended on experiments and modelling for imaging voids using ground penetrating radar (GPR). However, much can be learned from simple models. For example, a simple Ricker wavelet model can be used to illustrate some fundamental properties of the GPR response from voids, both air- and water-filled. In particular, reflections from the top and the bottom of a...
In order to design holographic and impulse GPRs, as well as metal detector (MD) sensors for humanitarian demining in the Donbass conflict zone, we have compiled a listing of the AP and AT mines that have been confirmed in use in Donbass, and their dimensions and construction. Just as importantly, we have attempted, from existing literature (since it is an active war zone), to characterize the specific...
Time-frequency spectral responses of an in-house built step-frequency continuous wave (SFCW) GPR (Y akumo) developed by Tohoku University and a commercial impulse GPR were studied and compared. The Yakumo SFCW GPR operates from 50 MHz to 1.5 GHz, and the center frequency of the commercial impulse GPR is 500 MHz. Both GPRs were probed on top of an embedded steel pipe overlaid by a concrete pavement...
Limestone is a widely used building material. Its degradation process is strongly linked to the water content, to which the radar waves are sensitive. In this paper, a model of stepped-frequency radar (SFR) wave propagation through partially wet limestone is proposed, in order to study the water transfer front in limestone. We assume the limestone as a two-layer (dry/wet) lossy medium and use an analytical...
We propose a plane wave model (PWM) which is derived based on analytical solution of a full wave model (FWM) applied to ground penetrating radar (GPR) signal propagation in layered media. The computation efficiency of PWM is enormous, and accuracy is comparable to FWMs. In this model, reflections from different interfaces and their higher order terms are expressed separately resulting in infinite...
An adaptive linear neuron network is employed for reversing the location and back scattering density of objects from ground penetrating radar data. The processing avoids the disadvantage of unknown electromagnetic velocity in a medium for the specific rebar detecting application. Based on the common-offset reflection GPR survey model, the network was derived by reconstructing and compressing the reflected...
Ground penetrating radar (GPR) velocity tomography has shown much promise in the detection of geological hazardous bodies. Using GPR velocity tomography technology, faults parallel to the transmission direction can be more accurately detected than faults perpendicular to transmission direction. This indicates that ray coverage has a great influence on inversion accuracy. In order to identify accurately...
A particularly challenging parameter for petroleum exploration in aeolian desert environments is the thickness of the low velocity layer (LVL), which can vary laterally due to numerous reasons, including variations in weathering depths or the presence of palaeochannels. Traditional methods of mapping the LVL, such as uphole seismic surveys, offer precise depth information but at disparate points....
Ground penetrating radar (GPR) is a very common technique for exploring the subsurface. Lately, a different use of GPR has emerged from the need to search for and rescue victims in collapsed buildings and/or rock falls. Since the employment of ultra-wideband (UWB) radar devices is still a very new technique for rescue teams, many technology changes and best practices are being developed. One of the...
The paper describes the testing of an obstacle-detection radar installed on the steerable head of a Horizontal Directional Drilling (HDD) equipment; the system was developed during the ORFEUS (Operational Radar For Every drill string Under the Street) project co-funded by the European Commission under the 7th Framework programme. HDD is a trenchless method of installing pipes and cables of various...
Lunar Penetrating Radar (LPR), equipped on the rover of Chang'E-3 mission (CE-3), estimates the thickness of lunar shallow structure and detects three layers structure. In order to analyze the data of LPR and build an interpretation and experimental model, in this paper, we carry out LPR simulation and processing algorithm to provide some reference for future LPR detection. Firstly, we build the stochastic...
In this work a numerical model capable to predict the electromagnetic response of railway ballast aggregates under different physical conditions has been calibrated and validated by a simulation-based approach. The ballast model is based on the main physical and geometrical properties of its constituent material and it is generated by means of a random-sequential absorption (RSA) approach. A finite-difference...
This study presents the findings of a GPR investigation at two archaeological sites in Vadnagar, India; Area 1: Gaon Tal near a Hindu Temple (23°47'19.57″N; 72°38'47.75″E) and Area 2: Baba No Tekdo locality II (23°47'30.53″N; 72°38'55.59″E). Area 1 was surveyed in two plots of dimensions 16m × 10m and 12m × 16m, and Area 2 in a single plot of size 40m × 36m. Total seventy-two profiles were taken using...
The GPR method has increasingly found application in non-destructive testing of reinforced concrete structures. This paper presents the new approach of modelling of the electromagnetic wave propagation for reinforced concrete structures with a complex system of reinforcement. Simulations of the GPR field were performed on a three-dimensional model of a footbridge using the FDTD method. Numerical maps...
In this work, the evolution of damages in pavement life cycle relative to rutting has been modeled in relevant pavement sections. Ground-penetrating radar (GPR) surveys were carried out at the rural road network scale using an air-launched pulsed radar system, 1GHz central frequency of investigation, linked to an instrumented van for collecting data at traffic speed. Surveys were performed in two...
The singularity expansion method (SEM) assumes that the electromagnetic scattering wave of an object has a fixed poles distribution, i.e. the resonant frequency is fixed. So the object can be identified by extracting poles from radar data. While studying ground penetrating radar (GPR) echo signal features of nonmetallic pipelines, the paper finds that the GPR signal's frequency center downshifts when...
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