Bodenradar

Bodenradar, in English ground-penetrating radar (GPR), is a geophysical method for imaging the subsurface. It uses high-frequency electromagnetic waves emitted by an antenna that is in contact with or near the ground. When the wave encounters interfaces with different dielectric properties, part of the energy is reflected back to the antenna and recorded as a function of time. The resulting radargrams provide a two-dimensional cross-section of subsurface structures and features.

A typical Bodenradar system comprises a transmitter, a receiver, an antenna or antenna array, and a data acquisition and processing unit. Modern setups allow for rapid collection of multiple parallel traces to build 2D profiles or 3D maps. Data processing includes filtering, deconvolution, migration, and time-to-depth conversion using estimated wave velocity, often derived from hyperbolic reflections or calibration measurements.

Frequency choice determines depth penetration and spatial resolution. Lower frequencies (tens of MHz) penetrate deeper but with coarser resolution, while higher frequencies (hundreds of MHz) yield finer detail near the surface. In well-drained soils, useful depth ranges may extend from a few centimeters to several meters; in conductive clays or saline environments, penetration is more limited.

Applications span archaeology, civil engineering, road and bridge assessment, utility detection, environmental and forensic investigations, and mining studies. Bodenradar can detect voids, roots, buried utilities, walls, floors, and changes in stratigraphy, but interpretation depends on contrast in dielectric properties and can be hampered by clutter, multiple reflections, and ambiguous signals.