The modular SDR board for universities is exactly what Fox-1 and Fox-2 (as well as future Fox's) aim to do! Unfortunatly noone here will get details on the current specs or design due to ITAR restrictions but if you become part of the Fox project engineers you'll see what's going on.
* I'll leave this e-mail with just a thought: *
*“Just remember - when you think all is lost, the future remains”* - Robert Goddard
Engineering is about doing things people say can't be done, think about the size/power requirements of satellites 20 years ago, 10 years, ago... their functional density....
It's not impossible, just difficult!
Thanks,
Brent, KB1LQD
On Thu, Sep 5, 2013 at 9:37 AM, M5AKA m5aka@yahoo.co.uk wrote:
But what if the SDX that flew on ARISSat, or the one that will be developed for the Future of the Fox series could be "sold"
(or
given) to the university cubesat community as a radio capable of being
used
to deliver science data?
Hi Zach,
Unfortunately there goes the CubeSat's power budget.
The SDX transponders have an overhead, not just in terms of the physical space they occupy, but the amount of power they consume.
I believe the most efficient SDX transponder has an overhead of some 350 mW above the power consumed by an analog linear transponder and a linear transponder itself would consume more power than a standard 9600 bps CubeSat telemetry module.
So it appears to be a non-starter for 1U CubeSats. Might be feasible on 3U CubeSats but it would mean much less power would be available for other experiments on the CubeSat.
The question is what's in it for the CubeSat team ? The answer may be a higher data rate, the existing 9600 bps just isn't fast enough. In theory, depending on the modulation employed, a 30 kHz bandwidth SDX transponder could generate a 96 kbps downlink which is much more useful. To some the trade-off of power budget for downlink speed may prove appealing.
At the moment it's all theoretical but certainly worth considering when a FOX-2 SDX transponder has been proven to work in space.
73 Trevor M5AKA _______________________________________________ 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