--- On Sat, 31/3/12, g0...@aol.com <g0...@aol.com> wrote: > It's technology like that combined with minaturised electronics and > structures that probably represents a future generation of 'HEO' > satelites. But they still have to negotiate the passage through the > radiation belts and that looks to be a slow process.
And a damaging process, I wonder if current generation SDX transponders would survive in that environment ? You could put up with it taking a year or two for a 2U or 3U CubeSat to get to HEO as long as it would still have a reasonable lifetime when it got there. With fold-out solar panels you might be able to generate 10 watts peak of solar power when it acheived HEO. The maximum transponder output may only be 3 watts PEP which would be a significant reduction on the 50 watts or so we've had with previous HEO's. One way to get around the reduced power may be to use lower frequecy bands, say 50 MHz uplink and 29 MHz downlink. This may reduce the loss on the downlink by 9 db or so although they may be some mechanical challenges to overcome with respect to the antennas. A MEO (say 8000 by 400 km) instead of an HEO would also reduce path loss - exciting times lie ahead. 73 Trevor M5AKA --- On Sat, 31/3/12, Trevor . <m5...@yahoo.co.uk> wrote: > An interesting Swiss project see http://www.uk.amsat.org/6180 > AMSAT-UK News on Twitter http://twitter.com/AMSAT_UK/ _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
