Although radar is typically associated with scanning the sky, it is also used for underground purposes. Ground-penetrating radar (GPR) is utilized to send signals beneath the surface and analyze their return to determine the presence of buried objects, similar to locating or identifying distant aircraft by detecting radar echoes. This technology can be constructed using some readily available materials at a relatively low price.
This project was created by [Mirel] using an Arduino Mega 2560 and antipodal Vivaldi antennas, which are a specific type of directional antenna. All items are placed on a compact wagon that is easily movable on the ground. A radar is activated by a switch connected to the wheels at set intervals as the wheels turn, emitting a signal and detecting reflections at various points. A range of 323 MHz to 910 MHz is used by it, and it shows a small visualization on an LCD screen connected to the Arduino.
Using this instrument enables you to observe varying densities and depths of materials beneath the surface. This can prove to be extremely useful when commencing a substantial excavation project, identifying rock layers or underground utilities prior to digging. [Mirel] provided all the hardware and software as open-source for this project, so if you want to explore a different approach to GPR, check out this project which includes extensive technical discussions on its operation.
Source: AFFORDABLE GROUND-PENETRATING RADAR
