To design and experimentally validate an antenna for underground communications for exploration missions.

Access to the subsurface of planetary bodies, is still a young research field with only limited experiences demonstrated by the space community. Underground access will enable scientific understanding of the planetary bodies and can potentially be essential for habitability. In this context, it is vital to provide communication links with above-ground stations or relay satellites. A wireless communication link appears to be the most attractive solution because of its higher flexibility compared to wired networks. Specifically, a few access points could allow communications over a large underground distance. The same operation with a wired network might require extremely long cables, which are impractical because of the corresponding high loss and transportation requirements.The activity intends to discuss possible scenarios and antenna configurations for establishing a wireless communication link between underground caves or tunnels and the outside, including signal propagation. The link includes an access point at the entrance of the cave/tunnel and underground relay antennas. . A tunnel (or a cave) may act as a waveguide, thus the frequency should be high enough to avoid cut-off. At high frequency, multimode propagation occurs generating a multipath transmission. A MIMO solution able to receive signal from different direction might maximize the throughput and shall then be investigated. Thus to perform the functional verification of the antenna, the activity encompasses the following tasks:- Consolidation of the requirements and review of terrestrial solutions for underground communications.- Trade-off analysis among several solutions and identification of the most promising antenna configuration.- Design and detailed analysis of the most promising solution.- Manufacturing and testing of a representative demonstrator of the antenna(a terrestrial COTS communication solution could be integrated with the antenna).