Mission Design for the CubeSat OUFTI-1

CHAPTER 4have to be smooth and their edges rounded• the use of Aluminium 7075 or 6061-T6 is suggested for the main structure.If others materials are used, the thermal expansion must be similar to thatof the deployment system material (Aluminium 7075-T73) and approved.This prevents the CubeSat to conk out because of an excessive thermaldilatation.• no electronic device may be active during launch. Rechargeable batterieshave to be discharged or the CubeSat must be fully deactivated• at least one deployment switch is required• antennas can be deployed only 15 minutes after ejection into orbit whilebooms and solar panels after 30 minutes• it has to undergo qualification and acceptance testing according to thespecifications of the launcher: at least random vibration testing at a levelhigher than the published launch vehicle envelope and thermal vacuumtesting. Each CubeSat has to survive qualification testing for the specificlauncher. Acceptance testing will also be performed after the integrationinto the deployment system.4.1.1 Amateur Radio and D-STAR systemBefore proceeding with the description of OUFTI-1, a brief introduction of thesatellite’s payload, represented by its communications system, is necessary.D-STAR, which stands for Digital Smart Technology for Amateur Radio, isan open ham radio protocol recently developed by the Japan Amateur RadioLeague (JARL). Its main features are the simultaneous transmission of voiceand data, the complete routing capacity (including roaming), the cross-bandcapability and the possibility of passing through the internet.It works over three possible frequencies and data rates:• 144 MHz ( 2m, VHF ), 4.8 Kbit/s• 440 MHz ( 70 cm, UHF ), 4.8 Kbit/s• 1.2 GHz ( 23 cm, SHF ), 4.8 Kbit/s or 128 Kbit/sPresently, in Europe only the first two frequencies are available.The D-STAR technology is in fact really developed in the United States, wheremany repeaters are operational, but it’s quickly extending in Europe: the firstrepeater in Belgium is at the University of Liège and it has been installed withinthe OUFTI-1 project.Galli Stefania 22 University of Liège