> I prefer the concept of the high altitude communications blimps
> which can float above cities for years, be easily retrieved for
> maintenance, cost nothing when compared to 'space birds' and don't
> have any of the dangers of rocket launching involved.
See:
157 m long (515 feet) and 62 m (203 feet) in diameter at the widest
point! That's nearly as long as the biggest Zeppelins and a lot
wider.
I would be most impressed if they can get this to work. Solar cells
and fuel-cell storage light enough to be kept up by helium at a 22 km
elevation with a 1 tonne telco payload - all kept in place with ion
engines, which as far as I know, only work at very low air pressures.
How then does it power itself up there? Or down?
Several tonnes of stuff floating above a populated area, ready to be
punctured by a meteor . . . get an insurance quote on that!
It has to cover a very large area, (19,000 square kilometers) with a
supposedly small piece of microwave spectrum - only 300 MHz. The
spectrum can be re-used in different directions with direcational
antennae of vertical and horizontal polarisations.
Get a quote on insurance against someone jamming the entire thing for
a lark or for financial gain.
- Robin
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Robin Whittle rw@firstpr.com.au http://www.firstpr.com.au
Heidelberg Heights, Melbourne, Australia
First Principles Research and expression: music, Internet
music marketing, telecommunications, human
factors in technology adoption. Consumer
advocacy in telecommunications, especially
privacy. Consulting and technical writing.
Real World Electronics and software for music: eg.
Interfaces the Devil Fish mods for the TB-303.
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