The application of finite-difference time-domain modelling for the assessment of GPR in magnetically lossy materials

Void detection beneath reinforced concrete sections: The practical application of ground-penetrating radar and ultrasonic techniques

“…It is also interesting to note that there is a strong asymmetry to the form and amplitude of the recorded rebar diffractions in the 450 MHz data, which can lead to the section being interpreted as having falsely dipping features. This phenomenon has also been observed in GPR data where there are there are shallow, strongly contrasting, regularly spaced, point or axis-linear target sources close to each other in the sub-surface (e.g., Cassidy and Millington, 2009;). If the separation distance between the targets is of the same order as the wavelength of the propagating GPR signal, and the data is collected along the line in the same direction, then the asymmetry of the diffractions (and therefore the relative dip direction of the features) appears to depend on whether the transmitter is leading the Tx-Rx pair or the receiver.…”

Effects of magnetite on high-frequency ground-penetrating radar

“…This interest has been driven by the realization that soil mineralogy is of considerable importance for modern land mine detection sensors, which often use high-frequency GPR (Takahashi et al, 2011), by the plans to include a high-frequency GPR system on one of the future Mars rovers (e.g., Ciarletti et al, 2011), and by the increased use of high-frequency GPR systems in engineering fields where magnetic material is likely encountered (Cassidy and Millington, 2009). In addition, ferrimagnetic minerals in soils may affect retrieval of soil moisture using C-and L-band radiometers and microwave satellite sensors, although this is not discussed in the relevant literature (e.g., Jackson et al, 1999;Moran et al, 2004;Barrett et al, 2009).…”

“…In recent years, new interest in the issue of ferrimagnetic minerals in the environment has arisen due to the effect they can have on the performance of GPR and other electromagnetic sensors. Areas of particular interest are related to Mars exploration programs (Coey et al, 1990;Grant et al, 2003;Leuschen et al, 2003;Bertelsen et al, 2004;Stillman and Olhoeft, 2008;Ciarletti et al, 2011), the detection of unexploded ordnance (UXO) and land mines (Van Dam et al, 2005;Takahashi et al, 2011), and civil engineering applications such as imaging of corroded steel-reinforced concrete and soils containing waste material of smelting operations (Cassidy and Millington, 2009). …”

An evaluation of Finite-Difference and Finite-Integration Time-Domain modelling tools for Ground Penetrating Radar antennas

“…Over the past 19 years gprMax has been one of the most widely used simulation tools in the GPR community. It has been successfully used for a diverse range of applications in academia and industry [16], [17], [18], [19], [20], [21], and has been cited more than 200 times since 2005 [22].…”