3STAR CUBESAT FOR THE GEOID MISSION

3STAR is the new cubesat educational project developed at Politecnico di Torino. 3STAR is thought in response to the European Space Agency call for proposals for the GENSO Experimental Orbital Initial Demonstrator (GEOID) mission, held by its Education Office. GEOID is a mission consisting in launching and operating several satellites to test the Global Educational Network for Satellite Operations (GENSO) system and to serve as test-bed for the HUMSAT (HUManitarian SATellite) international satellites constellation. HUMSAT will work as a communication-support network for areas without infrastructures or for developing countries. Moreover, the HUMSAT project is aiming at providing a wide range of applications such as climate change monitoring, remote disaster tracking, and public health communications. 3STAR will be one of the first twelve satellites of the GEOID constellation. The 3STAR mission consists of a 3U cubesat orbiting the Earth and acting as a data-relay platform and a space-based test bed for an Earth remote sensing experiment. The payloads of this satellite are two. The first is the HUMSAT payload, a communication equipment (basically a UHF transceiver, one antenna, and one data storage device) that meets the HUMSAT requirements, nonetheless remaining extremely simple and reliable. The second payload is the P-GRESSION (Payload for GNSS REmote Sensing and SIgnal detectiON) experiment, whose main goal is to perform measurements by means of radio occultation techniques and scattering theory, using GNSS signals. In this paper the 3STAR project and its main payloads are described along with a preliminary description of the GEOID/HUMSAT mission and an overview of the 3STAR system characteristics, Including the dedicated ground control station. The approach to the design is based upon a modular structure development. The paper will describe the 3STAR system into the details, highlighting the methods employed to develop the program, as well as the first results obtained.