[MLB-WIRELESS] hops over water - reflective properties of wat er for microwaves...

[Tony Langdon]

> I know some HAMs experiment with communications
> by bouncing lasers off clouds!  The other possibility

Cloud reflections require very short wavelengths.  Light is a good choice
for that (at least at night).  You'd have to get well into the 100's of GHz
or even THz range to get any appreciable reflections at microwave
frequencies - and then you get atmospheric absorption...

> is meteor trails.  It is possible to bounce radio
> waves off the plasma left by a meteor burning up.
> Communication is in bursts, but there are enough
> meteors out there to give useful average data rates.
> Going into pie in the sky mode, it would be an
> interesting project to build a global 'community
> wireless' network using meteor trails in place
> of satellites.  (Though it might turn out to just
> be HF radio reinvented??)

You would be limited in agregate data rates, as the highest efficiency for
meteor scatter is around the mid VHF range (50-150 MHz) where bandwidth is
limited.  There are amateur modes capable of exploiting multiple meteor
"pings", but they typically operate low data rates.

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