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Ground Penetrating Radar research? How much power do you need? There are nice chunks of UHF, SHF and EHF frequencies available to hams. (http://www.arrl.org/frequency-allocations) Are there other US TLAs that keep you from pointing you ham antenna at the ground? (CQ CQ CQ DX!) You would just have to incorporate your call sign in your modulation every 10 minutes.

And regarding PNW rain, Terabeam Free Space Optics started in Seattle. I had rackspace in the same colo that they started in (Westin Building.)

For some reason I can't get the paper to load, but anyway, does this still depend on weak initialization vectors?

I know that the original attack did depend on that, and most software and basestations have since been configured to avoid those weak IVs. I know that some stuff (like Nokia's basestations) are still weak agains the original attack (at least when tested with Kismet), however, against Cisco Aironets and almost any newer hardware I haven't been able to see this weakness in action when trying out if it really works...

(Terabeam uses the term "WEPPlus" about this - see http://www.terabeam.com/solutions/whitepapers/wep- plus.php )

Anyway, if this is just extension of the original attack, then it still requires those weak IVs to exist.

Or is it something completely new?

Now, the handy table here tells us that a 20-mile link has an attenuation of 138 dB for such a frequency. If we want a one-kilowatt beam to rip into the satellite's antenna and have an RF source delivering 16 MW (big generator!), we can only accept an attenuation factor of 16,000, call it 2 to the 14th, or 42 db.

Now, 138 - 42 is 96, so our antenna has to supply a 96 dB gain. That's 34 dB more than our 25-m antenna, or about 2500 times more. Since gain is proportional to the square of the diameter, we need an antenna 50 times (50 = sqrt(2500)) bigger than our 25-m dish. That's a 1250-m (4100-ft) antenna!

Which is why radar satellites need good old missiles. Not that accelerating a warhead to Mach 25 is a piece of cake either, but that's another story.

Extending range? Simple : remove the oxygen from the air.

Actually, there are folks using it over 2.5 km (with expensiv antennas, and NOT through walls) :
http://www.terabeam.com/solutions/whitepapers/bene fits-60ghz.php

(I suspect that the 10m might actually be a feature to allow frequencies to be re-used)

Preferably, fiber optics will be used. However, it is very difficult to have a good overview of possibilities, and fiber optics technology is apparently very expensive to implement.

You can ditch the fiber but keep the optics. Free Space Optics (FSO) has been around for a long time. Despite being somewhat obscure, it is a very mature technology with a lot of things going for it. It provides fiber level bandwidth without the cost of digging up the ground to lay down fiber. Rapid deployment and high mobility can save not only money but time as well. You didn't mention how far apart the residences are in the neighborhood, but unless you're rural and very spread out, FSO may perform satisfactorily with allowance for bad weather. Bad weather being fog and scintillation.

Fog is a problem if you're near the coast or a large body of water that can produce a lot of mist. A heavy mist can really hammer the signal by several dBs over long distances on the order of a mile/kilometer. Currently it is the largest obstacle faced by permament/semi-permanent FSO implementations. Atmospheric scintillation is the phenomenon that makes stars twinkle at night. It is caused by variations in atmospheric temperature that change the index of refraction an optical signal encounters as it zooms to its destination. This problem, however, is more or less solved by making the signal take parallel paths to the reciever.

you may be interested in the following companies among others.

tellaire

terabeam

fsona

airfiber

lightpointe

industry news and references:

http://www.freespaceoptics.org/
http://www.wcai .com/fsoalliance/

I was driving to work North on Willows Rd in Redmond, WA today and I saw Terabeam's laser flashing away. It is pointed almost directly along the road to their satellite building to the South.

I haven't noticed it before, so I wondered if they had some beam dispersement issues. I got a little concerned that the laser was damaging my eyes. Hopefully the power on the lazer diode is turned down. You never know what is going on in development hardware ;)

The light looks like your run of the mill strobe light. The pattern looks like the LEDs on your hub. Not sure why because that flash speed is not consistent with the marketing info on www.terabeam.com.

Unfortunately the fog here in the valley tends to prohibit their use of the system.

The FCC and other government institutions are always going to have a hand in anything that scatters signal at RF.

My bet is on optical line-of-sight being developed by companies like Terabeam. OK, right now it's expensive technology only practical for corporate customers. So were computers 30 years ago.

The advantage of LOS technology is that there is no shared spectrum, and therefore no legitimate need to regulate. The only people who might want to regulate it are neighborhood associations, for aesthetic reasons. However, most of them have accepted satellite dishes so a well designed optical LOS transceiver should pass also.

Regardless of who or how, the problem will be solved. One day, people will pay only the cost of the transceiver, and they will get free internet, phone, you name it. I told this to my Dad, who owns stock in the phone company and it made him a bit nervous. I told him not to sell yet, but in 20 to 30 years you might not want to be holding stock in any of the companies that sell bandwidth.