ULID: an Unconnected L-band Interferometer Demonstrator

Continuation of brightness temperature measurements at L- band is a major asset for soil moisture and ocean salinity studies in the long term. The SMOS mission, launched in 2009, has been followed by Aquarius and SMAP, but follow-on missions are still in the preliminary phases. One of the main expected improvements is on the spatial resolution, for which a 10-fold increase is needed.Such a massive improvement cannot be addressed with current technology and requires a major revisit of the acquisition of interferometric measurements.The mission described in this paper is the first step towards a complete system to satisfy these challenging requirements.