scholarly journals Analytical Investigation on a New Approach for Achieving Deep Penetration in a Lossy Medium: The Lossy Prism

2017 ◽  
pp. 17-24 ◽  
Author(s):  
Fabrizio Frezza ◽  
Patrizio Simeoni ◽  
Nicola Tedeschi
Keyword(s):  
Ground Penetrating Radar ◽  
Analytical Investigation ◽  
Deep Penetration ◽  
Leaky Wave ◽  
New Approach ◽  
Inhomogeneous Waves ◽  
Homogeneous Wave ◽  
Lossy Medium ◽  
Basic Ideas ◽  
Ground Penetrating

Recent studies highlighted deep-penetration prop-erties of inhomogeneous waves at the interface between a loss-less and a lossy medium. Such waves can be generated bymeans of radiating structures known as Leaky-Wave Anten-nas (LWAs). Here, a different approach is proposed basedon the use of a lossy prism capable to generate an inhomo-geneous wave when illuminated by a homogeneous wave. Thelossy prism is conceived and designed thinking of Ground-Penetrating Radar (GPR). The results achieved by the lossyprism will be compared with those obtained by means of a pre-viously designed LWA that was created with the identical ob-jective. The approach of this paper is purely theoretical, andit aims at providing basic ideas and preliminary results usefulfor an innovative LWA design.

Design of Shielding System for Impulse Ground Penetrating Radar Applications

2015 ◽  
Vol 656-657 ◽  
pp. 646-651 ◽  
Author(s):  
Tan Phuoc Dong ◽  
Huu Phu Bui
Keyword(s):  
Ground Penetrating Radar ◽  
High Performance ◽  
Signal Transmission ◽  
Design Procedure ◽  
External Noise ◽  
Deep Penetration ◽  
Antenna Coupling ◽  
Radar Applications ◽  
Ground Penetrating ◽  
Shielding System

In this paper, we propose a shielding system for impulse ground penetrating radar applications (GPR). The structure of shielding system is designed for our real impulse GPR application at 200 MHz central frequency for improving the deep penetration. The shielding system makes high quality of signal transmission from transmitter antenna to receiver antenna for impulse GPR system. It not only makes lowest T/R antenna coupling, high performance of antennas, preventing external noise but also reduces unnecessary air radiation which damages to the health of GPR user. A commercial absorbing material with a short thickness of 40mm is used to reduce the reflection of upper side of antenna in the cavity of shielding system. The design procedure is derived and its performance is explained. Shielding system is designed, simulated and optimized successfully in CST 2013 software. And it is fabricated with a good measurement results.

scholarly journals Study on Wavelet Entropy for Airport Pavement Inspection using a Multi-Static GPR System

Geophysics ◽  
2021 ◽  
pp. 1-74
Author(s):  
Lilong Zou ◽  
Kazutaka Kikuta ◽  
Amir M. Alani ◽  
Motoyuki Sato
Keyword(s):  
Wavelet Transform ◽  
Ground Penetrating Radar ◽  
Large Area ◽  
New Approach ◽  
Wavelet Entropy ◽  
High Entropy ◽  
Airport Pavement ◽  
Base Experiment ◽  
Pavement Structures ◽  
Ground Penetrating

The multi-layer nature of airport pavement structures is susceptible to the generation of voids at the bonding parts of the structure, which is also called interlayer debonding. Observations have shown that the thickness of the resulting voids is usually at the scale of millimeters, which makes it difficult to inspect. The efficient and accurate characteristics of ground penetrating radar (GPR) make it suitable for large area inspections of airport pavement. In this study, a multi-static GPR system was used to inspect the interlayer debonding of a large area of an airport pavement. A special antenna arrangement can obtain common mid-point (CMP) gathers during a common offset survey. The presence of interlayer debonding affects the phase of the reflection signals, and the phase disturbance can be quantified by wavelet transform. Therefore, an advanced approach that uses the average entropy of the wavelet transform parameters in CMP gathers to detect the interlayer debonding of airport pavement is proposed. The results demonstrate that the regions with high entropy correspond to the regions where tiny voids exist. The new approach introduced in this study was then evaluated by a field-base experiment at an airport taxiway model. The results show that the proposed approach can detect interlayer debonding of the pavement model accurately and efficiently. The on-site coring results confirm the performance of the proposed approach.

A New Approach of Detecting and Evaluation Railway by Using the Train-Mounted Ground Penetrating Radar in China

2011 ◽  
Vol 243-249 ◽  
pp. 4351-4355
Author(s):  
Jie Liu ◽  
Yuan Shui Cheng
Keyword(s):  
Data Processing ◽  
Ground Penetrating Radar ◽  
Stable Structure ◽  
New Approach ◽  
Highly Effective ◽  
Ground Penetrating

Stable structure of subgrade of railway is an important foundation for safety of train. Rising of speed and heavy transport tasks accelerate deterioration of ballast and increase disease of subgrade. It is more important how to detect and maintain the condition of ballast and subgrade highly effective, faster and without any destruct. In recent years, the ground penetrating radar has been an effective method for detecting and evaluation ballast and subgrade. This paper present application of detecting and evaluation ballast and subgrade by using the train-mounted-multicenter ground penetrating radar(GPR), data processing and interpretation, acknowledge and some problem.

scholarly journals Ground-penetrating radar survey at Falerii Novi: a new approach to the study of Roman cities

Antiquity ◽  
2020 ◽  
Vol 94 (375) ◽  
pp. 705-723 ◽  
Author(s):  
Lieven Verdonck ◽  
Alessandro Launaro ◽  
Frank Vermeulen ◽  
Martin Millett
Keyword(s):  
Ground Penetrating Radar ◽  
New Approach ◽  
Ground Penetrating

Abstract

scholarly journals Multiple-ring Circular Array for Ground-Penetrating Radar Applications: Basic Ideas and Preliminary Results

2017 ◽  
pp. 25-29
Author(s):  
Roberto Vescovo ◽  
Lara Pajewski
Keyword(s):  
Antenna Array ◽  
Ground Penetrating Radar ◽  
Dynamic Range ◽  
Circular Array ◽  
Radar Systems ◽  
Radar Applications ◽  
Basic Ideas ◽  
Ground Penetrating ◽  
Low Dynamic Range ◽  
Multiple Ring

In this paper, the possibility of using a multiple-ring circular array as an antenna array for Ground-Pene-trating Radar systems is investigated. The theory behind theproposed idea is presented. The preliminary numerical re-sults that are obtained suggest that the proposed congura-tion is promising. It allows achieving a wide frequency bandand low dynamic range ratio of excitations, thus simplifyingthe feeding network. Further interesting requirements maybe satised by exploiting a combination of deterministic andstochastic synthesis techniques to design the array.

scholarly journals Verification of the electromagnetic deep-penetration effect in the real world

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Paolo Baccarelli ◽  
Alessandro Calcaterra ◽  
Fabrizio Frezza ◽  
Fabio Mangini ◽  
Nicholas Ricciardella ◽  
...  
Keyword(s):  
Electromagnetic Waves ◽  
Deep Penetration ◽  
Practical Relevance ◽  
Leaky Waves ◽  
New Approach ◽  
Penetration Effect ◽  
Inhomogeneous Waves ◽  
Lossy Media ◽  
Theoretical Evidence ◽  
First Time

AbstractThe deep penetration of electromagnetic waves into lossy media can be obtained by properly generating inhomogeneous waves. In this work, for the very first time, we demonstrate the physical implementation and the practical relevance of this phenomenon. A thorough numerical investigation of the deep-penetration effects has been performed by designing and comparing three distinct practical radiators, emitting either homogeneous or inhomogeneous waves. As concerns the latter kind, a typical Menzel microstrip antenna is first used to radiate improper leaky waves. Then, a completely new approach based on an optimized 3-D horn TEM antenna applied to a lossy prism is described, which may find applications even at optical frequencies. The effectiveness of the proposed radiators is measured using different algorithms to consider distinct aspects of the propagation in lossy media. We finally demonstrate that the deep penetration is possible, by extending the ideal and theoretical evidence to practical relevance, and discuss both achievements and limits obtained through numerical simulations on the designed antennas.

scholarly journals An Analytical Study of Electromagnetic Deep Penetration Conditions and Implications in Lossy Media through Inhomogeneous Waves

Materials ◽  
2018 ◽  
Vol 11 (9) ◽  
pp. 1595 ◽  
Author(s):  
Paolo Baccarelli ◽  
Fabrizio Frezza ◽  
Patrizio Simeoni ◽  
Nicola Tedeschi
Keyword(s):  
Electromagnetic Waves ◽  
Plane Waves ◽  
Deep Penetration ◽  
Practical Implementation ◽  
Penetration Effect ◽  
Inhomogeneous Waves ◽  
Inhomogeneous Plane ◽  
Lossy Medium ◽  
Lossy Media ◽  
Inhomogeneous Plane Waves

This paper illustrates how the penetration of electromagnetic waves in lossy media strongly depends on the waveform and not only on the media involved. In particular, the so-called inhomogeneous plane waves are compared against homogeneous plane waves illustrating how the first ones can generate deep penetration effects. Moreover, the paper provides examples showing how such waves may be practically generated. The approach taken here is analytical and it concentrates on the deep penetration conditions obtained by means of incident inhomogeneous plane waves incoming from a lossless medium and impinging on a lossy medium. Both conditions and constraints that the waveforms need to possess to achieve deep penetration are analysed. Some results are finally validated through numerical computations. The theory presented here is of interest in view of a practical implementation of the deep penetration effect.

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