Use of antenna arrays for GPR surveying in archaeology

Abstract

Among the different geophysical prospecting methods applied in archaeology, ground‐penetrating radar is one that still requires a lot of time to carry out field recordings. A duo‐antenna configuration is proposed that will halve the time needed in the field. Tests have shown that this can be done without any interference between the two antennae. The signals from different antennae do not have the same characteristics and the spectrum and amplitude of the traces are not the same. The use of spectral whitening and energy matching for adjacent traces or samples makes the data sets as similar as possible to allow for unperturbed time‐ or depth‐slices. As a side effect, spectral whitening enhances the vertical resolution and penetration depth of the method.

Common‐ and multi‐offset ground‐penetrating radar study of a Roman villa, Tourega, Portugal

“…The faster data can be recorded in the field without appreciably compromising data quality, the more successful that method is in near-surface exploration (Leckebusch, 2005). The multi-offset profiles were acquired over the large doublewalled structure to achieve a greater depth penetration and improved image clarity compared with the 200 MHz common-offset profiles.…”

Efficient, large‐scale archaeological prospection using a true three‐dimensional ground‐penetrating Radar Array system

“…Over the past years attempts for increased efficiency and resolution of GPR measurements through the use of parallel two-dimensional measurements have been observed (Pipan et al, 1999;Whiting et al, 2001;Neubauer et al, 2002;Seren et al, 2004;Leckebusch, 2005). The collection of two-dimensional GPR sections with dense cross-line spacing and their exact positioning is time-consuming (Leckebusch and Peikert, 2001;Slob et al, 2003).…”

“…The collection of two-dimensional GPR sections with dense cross-line spacing and their exact positioning is time-consuming (Leckebusch and Peikert, 2001;Slob et al, 2003). To overcome this several antennae can be used precisely positioned in multichannel antenna arrays, as demonstrated by both operators (Leckebusch, 2005(Leckebusch, , 2009Francese et al, 2009;Linford et al, 2009Linford et al, , 2010 and GPR system manufacturers (Gustafsson and Alkarp, 2007). To achieve fullresolution three-dimensional imaging (without aliasing the data) the individual channel spacing should, however, not exceed 0.25 of the wavelength of the antennae centre frequency (Grasmueck et al, 2005;Booth et al, 2008;Novo et al, 2008).…”

Multi-offset ground penetrating radar data for improved imaging in areas of lateral complexity — Application at a Native American site

“…Acquiring traces continuously while moving the antenna(e) does not affect the signal (Leckebusch, 2005). However, due to the sled mount, there may be some additional high frequency noise.…”

“…Just as common offset surveys have been partially automated by mounting the antennae on a sled/wagon (Lehmann and Green, 1999), we have similarly automated this multioffset survey by recording the traces continuously as common source gathers, while ensuring positioning accuracy and signal quality is maintained. The faster the data can be recorded in the field, the more successful that method is in near-surface exploration (Leckebusch, 2005). This continuous trace acquisition, termed rapid multi-offset acquisition, halved the acquisition time of this multioffset dataset in comparison to manually placing the antenna at each trace offset (stationary multi-offset acquisition).…”