ground-probing radar
Quick Summary
Ground-probing radar (GPR) is a type of radar technology that uses radio waves to image the subsurface. Unlike typical radar that reflects off surfaces, GPR's lower frequencies (below several hundred megahertz) allow energy to penetrate the ground. This enables the detection of buried objects such as tunnels, utility pipes, and cables, and aids in archaeological investigations and monitoring subsurface conditions of roads and bridges.12
GPR systems operate at frequencies ranging from 5 to 500 MHz, balancing the need for good penetration (low frequencies) with high resolution (wide bandwidth). The range of GPR is typically between 1 to 10 meters (3.3 to 33 feet) due to high signal loss in the ground. The antenna can be placed directly on the ground, and GPR units are generally portable.2
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