Experimental Verification of a Digital Delay Transponder Used as an In-Ice Synthetic Aperture Radar Reference Target

Low-frequency radar systems offer great potential to support navigation systems of exploratory ice-penetrating probes for cryospheric applications. Due to the comparably small radar cross-section (RCS) of such probes, transponder-like functionalities are mandatory to realise an increased RCS for a reliable in-ice detection and localisation of these probes. To support such applications, a miniaturised monostatic digital delay transponder was developed and tested in a measurement scenario with an airborne synthetic aperture radar (SAR) sensor on an alpine glacier.