(account deleted) 28 Apr 2007 12:14
Microcontroller collects data from payload/satellite systems and converts to stream of 8-bit binary numbers - onboard data handling
Modulator frequency modulates 8-bit binary numbers into something like morse code
Morse code is encoded into AX.25 protocol by terminal node controller (TNC)
TNC ‘packetizes’ data and ‘keys’ the transmitter (adds satellite ‘call sign’ to data)
Transmitter sends signal to ground station via antenna
Radio operating at UHF at ground station receives data signal and encodes stream to form required for data analysis
Ground Station transmits commands to the satellite (e.g. on/off commands for instruments)
Commands received by receiver and processed by microcontroller
For Ground Station equipment – can use National Space Centre
