Re: All Satellites (Alan P. Biddle)
At a SmallSat conference I attended on behalf of AMSAT this summer, I was amused at the casual assumption by a researcher that 50, Five Oh, cubesats could be launched as part of an upper atmosphere project using ham frequencies for the downlinks. (They would have a lifetime of only 3-4 months.) Jan King, W3GEY/VK4GEY, who does coordination of satellite frequencies, gently but firmly brought them down to earth a bit.
On the one hand, we get new hams with interests in space communications from these projects, but on the other we need to prevent the de facto appropriation of needed frequencies. A fine line to walk.
Alan WA4SCA
The thing that worries me the most is that the de facto appropriation of our amateur satellite frequencies seems very likely if we continue along a path which keeps us from filling those slots with payloads of our own. All this complaining about cubesats and the use of amateur frequencies for telemetry is kind of pointless if we aren't using those frequencies and have no prospect of using those frequencies in the foreseeable future.
It seems to me that coordinating 50 cubesats for four months could be a tractable problem, depending on the precise nature of the signals and their orbital spacing. It's not like there is a huge number of operational amateur satellites that they'd have to avoid.
Mark K6HX
Isn't it neat that Amateur Radio allows you to have a very narrow interest and get enjoyment out of it. From HF to multi GHz. From terrestrial to EME.
One subset is amateur satellites. Further subsets within amateur satellite includes those who love to work the FM Grid Sats, others like the "beep" Sats while others explore the old dead birds looking for a Phoenix a la AO-7.
To complain about the use of spectrum by one group or another is nuts. In the last day I've read such nonsense as "use of amateur frequencies for telemetry". Duh? Was it being used for something else? Did anyone notice that the "beep" Sats for the most part do their beeping on UHF. Those are not exclusive amateur frequencies. We, as amateurs, are the SECONDARY user of a shared frequency.
In the meantime, instead of complaining, get involved with your local CubeSat project to make sure that a FM or linear transponder is part of the spec. I think Delfi is a perfect model for us to pursue. Post science, post amateurs assisting with near whole earth orbit data acquisition, the satellite is turned over for amateur use. What a wonderful model of collaboration and win-win Delfi set for all of us.
Which leads me to my final comment on this Friday night rant... I don't expect to see another HEO or MEO in my life time. I think there is a better chance to see a constellation of LEO picosats running a mesh-like network. A network built up gradually over time by the CubeSat community 2 or 3 cubes at a time over many years costing no one group an arm and a leg to move toward that goal. No one launch failure jeopardizing the big picture. No one satellite failing in the constellation putting down the whole network or our enjoyment of it use.
Step'n off the soap box...
73, Alan VE4YZ EN19kv AMSAT LM 2352 http://www.wincube.ca
On Fri, Sep 25, 2009 at 7:15 PM, Mark VandeWettering [email protected] wrote:
At a SmallSat conference I attended on behalf of AMSAT this summer, I was amused at the casual assumption by a researcher that 50, Five Oh, cubesats could be launched as part of an upper atmosphere project using ham frequencies for the downlinks. (They would have a lifetime of only 3-4 months.) Jan King, W3GEY/VK4GEY, who does coordination of satellite frequencies, gently but firmly brought them down to earth a bit.
On the one hand, we get new hams with interests in space communications from these projects, but on the other we need to prevent the de facto appropriation of needed frequencies. A fine line to walk.
Alan WA4SCA
Tell them they can put up 500, as long as the downlink is on S-band :-)
73, Bruce VE9QRP
participants (3)
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Alan VE4YZ -
Bruce Robertson -
Mark VandeWettering