
LED BY: Andy Thomas, Jon Heath (two experienced ham-radio operators) & Daniel Brandt (Uni. of Leicester)
CUBESAT TEAM:
Comms team: Joanne Askew, Neil Gray, Ryan Laird.
Also present: David Acreman, Lucy Benson, Dylan Bishop, Glen Cornhill, David Gray, and Robert Royles.
Contact: Andy Thomas – email: ku.oc.oohay|liamsamohtydna#ku.oc.oohay|liamsamohtydna
When e-mail put in Leicester/ Cubesat in title.
LEO – about 400km, general gravitational Doppler shift (not relativistic), 18,000mph.
Doppler shift – worse high frequency (Maybe use about 145MHz, 436MHz*)
• 436MHz best sort of frequency
Downlink 2.4Ghz – technical problems using higher frequency.
Burst of Morse code data – keeping beacon on may cause problems due to power restraints. Command on/off, program when to come on/off – e.g. after 6 orbits send data down.
Typical LEO – 84% passage of 30˚ above the horizon or less. No problems with water, leaves at the frequency using.
Japanese Cubesat – send down on command, CW beacon – Morse code
Quakesat – (research)
Packet radio – use equipment at NSC!!!
Licensing who needs? – easy to obtain, not a problem. International arrangement of frequency allocation - amateur radio band.
Look into National Lottery funding.
Link budgets
Antenna – “tape” measure deployment may be useful!? (Look into more)
Amsat convention every year – Surrey University
Comms system
Tranceiver (transmitter, receiver) – use NSC
Modulator (frequency modulates wave form, can use morse code, bandwidth 5kHz, freq. channels 12.5kHz wide.)
TNC (modem, TX) Bell 202 codes, audio freq shift keying AFSK.
Command receiver – on board data handling
Other
Oscar 1 – satellite, constraints, American airforce launch (Look into more)
Hi resolution pics -> 9K6? 38K5?
Cubesat could be good tool for teaching at schools as could easily set up equipment to receiver equipment, portable.
Useful websites:
http://andythomas.org.uk
www.celestrak.com
www.cubesat.org.uk
www.amsat.org (Cubesat section, LH column => archives, posts, debate useful!)
NEXT MEETING AFTER EASTER!!!
TUESDAY 15 MAY 5.30PM SRC
