Just throwing this out there:
1. University cubesats tend to want to occupy amateur satellite service spectrum for their science missions, V/U is common. 2. Most *science* missions are only designed to last a few years, but the orbits will last a while longer. 3. How many science missions have been completed, but the spacecraft is still in orbit and occupying amateur spectrum? (I don't know the answer but I suspect it's a decent number, probably out of single digits and into double digits, see http://www.nasa.gov/directorates/heo/home/CSLI_selections.html to get an idea of the number of cubesats going up from universities, note the number of "in work") 4. What if those university spacecraft carried Software Defined Radio technology as their primary method for delivering their mission data to the ground? 5. What if upon completion of their mission the universities turned over control of the spacecraft to AMSAT. 6. AMSAT then reconfigures the spacecraft such that the SDRs are now used for voice or data relay (FM, Linear, packet, whatever). 7. Now all of a sudden, hams don't have to wait for a new spacecraft to get built and find a launch. Birds already in orbit, that are using Amateur Spectrum, now all of a sudden are providing a service to the Amateur community.
Personally, I'm glad the universities are using Amateur Radio spectrum for their science missions. I view the skies as a "target rich environment" even if all I can do is listen to these birds. However, it would be nice if the birds occupying amateur spectrum actually provided a service to the amateur community. 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? Their science mission concludes, control is turned over to AMSAT, the radios are reconfigured, and they become transponder birds for the ham community.
At the rate that these spacecraft are going up, even if we nab only 10% of the spacecraft listed on the link above and convince them to fly SDRs that can be reconfigured, that's roughly 9 satellites that over time become useable by the ham community as voice/data transponders. We don't have to build them, we don't have to find a launch, we don't have to do anything but wait until the science mission is over and then play. Will the spacecraft be of the same quality of what comes out of AMSAT? Maybe, maybe not, but even if one only lasts a year as an FM or Linear Transponder, I'd take it, and use it.
Granted, who knows what the orbits would be, so a replacement for AO-40? Probably not. But would the Amateur Satellite community accept maybe instead of 1 really long pass from a HEO bird, maybe in that same time frame 10 or 20 or maybe even 50 passes from multiple lower birds (I made these numbers up, no idea what the actual numbers would be)?
Granted, there is a LOT that would go into making this idea possible. We'd have to have an SDR the universities are willing to use, probably one with flight history (cough, Fox-2, cough). We'd have to have someone go around to the Universities and "sell it" to the Principal Investigators that our radio will work for them (technical issues aside, maybe they get a little PR by adding support for the Amateur community onto their list of mission objectives). If they agree to fly the radio, and then turn over control, we need to be capable of supporting those spacecraft from an Operational point of view when the time comes. We would need to have some sort of "filter" such that if they drive the heck out of their spacecraft to the point that it is nearly dead when their science mission concludes we have the option to reject taking the spacecraft over. Etc. Etc. Etc.
There's a lot of "what ifs" up there, but my favorite "what if" to think about is: what if the 89 satellites on that link above were capable of supporting amateur use at the conclusion of their science missions (Fox-1 is on that list, so ok 88 satellites)? 89 satellites + what AMSAT has and is still putting up? Can't make a contact during field day on an FM bird because of crowding, no problem, you have 5 other satellites to choose from and try.
My second favorite "what if" to think about is: what if the university cubesats occupying amateur spectrum actually provided a service to the amateur community?
A traditional replacement of AO-40? No. Effectively reproducing the similar amounts of access time and capabilities of AO-40? Maybe.
Like I said, just throwing the idea out there...
-Zach, KJ4QLP
You just described the objective of the Fox-1 FM RF board. This is exactly the position AMSAT is trying to get into. There's a YouTube video that interviews Barry Baines and he ends up explaining this goal. I'd link to it but am currently typing this on my phone .
Zach Leffke zleffke@vt.edu wrote:
Just throwing this out there:
- University cubesats tend to want to occupy amateur satellite
service spectrum for their science missions, V/U is common. 2. Most *science* missions are only designed to last a few years, but the orbits will last a while longer. 3. How many science missions have been completed, but the spacecraft is still in orbit and occupying amateur spectrum? (I don't know the answer but I suspect it's a decent number, probably out of single digits and into double digits, see http://www.nasa.gov/directorates/heo/home/CSLI_selections.html to get an idea of the number of cubesats going up from universities, note the number of "in work") 4. What if those university spacecraft carried Software Defined Radio technology as their primary method for delivering their mission data to the ground? 5. What if upon completion of their mission the universities turned over control of the spacecraft to AMSAT. 6. AMSAT then reconfigures the spacecraft such that the SDRs are now used for voice or data relay (FM, Linear, packet, whatever). 7. Now all of a sudden, hams don't have to wait for a new spacecraft to get built and find a launch. Birds already in orbit, that are using Amateur Spectrum, now all of a sudden are providing a service to the Amateur community.
Personally, I'm glad the universities are using Amateur Radio spectrum for their science missions. I view the skies as a "target rich environment" even if all I can do is listen to these birds. However, it would be nice if the birds occupying amateur spectrum actually provided a service to the amateur community. 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? Their science mission concludes, control is turned over to AMSAT, the radios are reconfigured, and they become transponder birds for the ham community.
At the rate that these spacecraft are going up, even if we nab only 10% of the spacecraft listed on the link above and convince them to fly SDRs that can be reconfigured, that's roughly 9 satellites that over time become useable by the ham community as voice/data transponders. We don't have to build them, we don't have to find a launch, we don't have to do anything but wait until the science mission is over and then play. Will the spacecraft be of the same quality of what comes out of AMSAT? Maybe, maybe not, but even if one only lasts a year as an FM or Linear Transponder, I'd take it, and use it.
Granted, who knows what the orbits would be, so a replacement for AO-40? Probably not. But would the Amateur Satellite community accept maybe instead of 1 really long pass from a HEO bird, maybe in that same time frame 10 or 20 or maybe even 50 passes from multiple lower birds (I made these numbers up, no idea what the actual numbers would be)?
Granted, there is a LOT that would go into making this idea possible. We'd have to have an SDR the universities are willing to use, probably one with flight history (cough, Fox-2, cough). We'd have to have someone go around to the Universities and "sell it" to the Principal Investigators that our radio will work for them (technical issues aside, maybe they get a little PR by adding support for the Amateur community onto their list of mission objectives). If they agree to fly the radio, and then turn over control, we need to be capable of supporting those spacecraft from an Operational point of view when the time comes. We would need to have some sort of "filter" such that if they drive the heck out of their spacecraft to the point that it is nearly dead when their science mission concludes we have the option to reject taking the spacecraft over. Etc. Etc. Etc.
There's a lot of "what ifs" up there, but my favorite "what if" to think about is: what if the 89 satellites on that link above were capable of supporting amateur use at the conclusion of their science missions (Fox-1 is on that list, so ok 88 satellites)? 89 satellites + what AMSAT has and is still putting up? Can't make a contact during field day on an FM bird because of crowding, no problem, you have 5 other satellites to choose from and try.
My second favorite "what if" to think about is: what if the university cubesats occupying amateur spectrum actually provided a service to the amateur community?
A traditional replacement of AO-40? No. Effectively reproducing the similar amounts of access time and capabilities of AO-40? Maybe.
Like I said, just throwing the idea out there...
-Zach, KJ4QLP
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
Hi Zach,
On 9/5/2013 9:03 AM, Zach Leffke wrote:
Just throwing this out there:
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? Their science mission concludes, control is turned over to AMSAT, the radios are reconfigured, and they become transponder birds for the ham community.
Yes, and this is one of the goals of the Fox project too! We can partner with the universities, providing the transponder and bus (Fox-1A, RadFXSat) which may be dedicated to their experiment for some years or not, depending on the downlink needs (i.e. Fox-1 has high speed for youse guys, and the slow speed accommodates Vanderbilt). We have a transponder dedicated to ham use when the experiment(s) are through or even while they are going on. Or once Fox-1 is finished and all of the details are published, any institution could use the design for their project and "give back" (as a gesture of kindness for all the work we saved them and excellent science we helped them gather) the transponder when they are done with their science. It gives them a proven reliable system that they don't have to engineer on their own. It gives us another transponder if not on launch, at least eventually. Fox-2 will do the same for ham satellite SDX. Anybody know any young people who are in a position to help sell this paradigm to universities? ;-)
Jerry
Here is the video where this mission object is stated: http://www.youtube.com/watch?feature=player_detailpage&v=3o_PV2b9F6g#t=4...
On Thu, Sep 5, 2013 at 8:44 AM, n0jy n0jy@n0jy.org wrote:
Hi Zach,
On 9/5/2013 9:03 AM, Zach Leffke wrote:
Just throwing this out there:
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? Their science mission concludes, control is turned over to AMSAT, the radios are reconfigured, and they become transponder birds for the ham community.
Yes, and this is one of the goals of the Fox project too!
We can partner with the universities, providing the transponder and bus (Fox-1A, RadFXSat) which may be dedicated to their experiment for some years or not, depending on the downlink needs (i.e. Fox-1 has high speed for youse guys, and the slow speed accommodates Vanderbilt). We have a transponder dedicated to ham use when the experiment(s) are through or even while they are going on. Or once Fox-1 is finished and all of the details are published, any institution could use the design for their project and "give back" (as a gesture of kindness for all the work we saved them and excellent science we helped them gather) the transponder when they are done with their science. It gives them a proven reliable system that they don't have to engineer on their own. It gives us another transponder if not on launch, at least eventually. Fox-2 will do the same for ham satellite SDX. Anybody know any young people who are in a position to help sell this paradigm to universities? ;-)
Jerry
______________________________**_________________ 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-bbhttp://amsat.org/mailman/listinfo/amsat-bb
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
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
participants (5)
-
Brenton Salmi -
Bryce Salmi -
M5AKA -
n0jy -
Zach Leffke