Autonomous and semi-autonomous radio commanding of VZLUSAT-1 nanosatellite from ground control station in Pilsen

Abstract

Nano- and pico-satellites are currently used as low cost in-orbit-demonstrators of new technologies or for the university research. These satellites are launched to the low Earth orbits and radio commanded from the ground control stations. Most of them are equipped with narrow band transceivers working in UHF radio amateur frequency band, reaching only low data transmission rates. Low Earth orbits also limits the number and duration of satellite passing in the range of ground control station. One ground control station has approximately six satellite passes per day, each with duration only in few minutes. This strictly limits the amount of transmitted data between satellite and ground control station. In this paper the software controlled and assisted radio commanding of VZLUSAT-1 nanosatellite during the QB50 scientific mission is described. Two basic modes of satellite radio commanding are described with the aim to increase data throughput during commanding. Software controlled autonomous and software assisted semi-autonomous modes allow effective commanding of satellite while keeping the attention of satellite operator to the satellite condition and keeping the full control over the radio transmission as radio amateur regulation requires. Also the critical operational limits of satellite electronics faces to cosmic vacuum and radiation environment have to be continuously monitored for safety satellite operation.