Long range wireless ethernet...

Randy's PC runs off solar panels down in a canyon, off the grid in my neck of Ozark woods. The usual wireless solutions wont work. There is

*no* 'line of sight'. Randy's house is in a real nice grove of ancient oak that he most definately does not want to cut to clear; and besides the topo suggests that a bluffline mite be in the way.

But many of us are old enough to remember TV 'ghosting'. I figure I mite be able to bounce a signal off the canyon wall, or pick a frequency low enough to bend around the bluffline.

I've got some 75 foot pines in my yard, and the needle length is long enough, when wet, to ground out any wireless signal over 300 mhz. I can understand engineers being concerned about RFI in urban environments, and wanting lots of channels to chose from, which you get when the frequency is high enough. But we dont have the problem. We've got lotsa dead air to work in.

So- what is the bandwidth of each of the 4 ethernet channels? Has anyone else tried using notch filters or whatever to narrow cast 4 signals between tuned antennas? I can see using pulse emitters & detectors on say, 180mhz carrier wave that would either add to, or clip the peaks, and result in 180meg bits/sec/channel. No IF needed. Without an IF, a tuner wouldnt tune it. 90mbps even if half duplex.

Such a system could result in point to point communications the givernment could not tap. Aint no wire. Dont matter if there's a court order or not. Not that anyone cares what we have to say to each other, or where he surfs.

But in any case, I can see that it mite be necessary to use the com port to set the transmitter frequencies to find out what bands would work best here, and maybe boost the RF output to adapt to weather conditions.

Reply to
Day Brown
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you're dreaming.

think: "Sigint Surveillance Satellites"

the gov can pick up -any- signal, anywhere on earth. your signal is reflecting off things and some of it is going straight up...and these freqs go right through the ionosphere instead of reflecting....that's why they're limited to LOS.

...and once received by the ever-present monitoring satellite, your 'pulse' signal will be as trivially easy to read as any regular AM broadcast station.

back to the real world...

regarding the 'bounce' technique, yes, that's -possible-. Pick up some 900mhz gear and a pair of old C-band sat-tv dishes. The bigger the better (i.e. 12' is better than 6'). As I recall, an 8' dish on

900 gives you around 21db gain, in the real world.

and give it a try.

if there's only a single ridgline between ends, as you say; then you should put either a reflector up there (depending on angles involved), or a passive-repeater(pair of high-gain antennas back to back).

a reflector can be any large flat metal surface. 1/4" hardware-cloth can work; if you can keep it -flat-, and oriented properly....i.e. taut over 2x4 framing, and securely mounted.

Such passive repeaters generally fail if centrally located, but sometimes work if located very close to one end of the path.

finally, unless you want to spend the next 5 years f****ng around, just get some 900 gear and put a battery-powered repeater on top of that ridgeline, with a PV panel to keep it charged and a pair of high-gain yagis. Simple, almost guaranteed to work (assuming near-LOS between the two sites and the repeater).

If you both have true LOS to the ridgetop (no trees), even consumer-grade WiFi 2.4gig equipment will work using the repeater-scheme; if using high-gain ants.

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Neither of us has true LOS. I've got tall pines on my end, he's got oaks on his. Our situation is fairly common; after all, folks move here cause they like the way the woods looks. They dunno about the ISP problems.

Neither of us owns the ridge line either, which is another common problem- the economic charges for installation of repeaters. Passive or otherwise.

So far as I can tell, nobody who lives in the coutry designs communications equipment for people who live in the country.

Reply to
Day Brown

Are there still satellite ISPs covering North America.

802.11a has a subband that is licensed for significantly higher power than 802.11b/g. It's 5 GHz and a modest dish antenna can give spectacular gain. Proxim and Lucent and the usual suspects make the gear as long-haul TCP solutions.

I suggest you check your back account and then get in touch with a local ham radio guy who can eyeball your problem and make recommendations.

In ski country I've seen a cabin at the base of a cliff with a VHF TV antenna on the roof pointing straight up. It was clearly someone that got a useful TV signal via edge diffraction. It was a textbook situation.

Reply to
Al Dykes

Yes, of course. But satellite data is 600$ for the hardware plus 70$/mo for the minimum bandwidth which is way more than Randy needs. He has lots of other things to do besides sit in front of a PC.

I looked at ham packet radio. 9.6kbps. compared to 56kbps for the standard POTS dialup. yech.

It shouldnt be rocket science even if it is unusual. I'd hoped someone had already found a FM/VHF/UHF band solution. There are pulse emitters and detectors that reasonably should be able to put data on an analogue signal, that are on IC chips that only cost a few bucks each. But I need to know what the amplitude and frequency of the data stream for ethernet channels is.

Reply to
Day Brown

Is there someone you know down the ridge line where you could make a dog leg line of sight?

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The woods here is so thick you cant even get a rifle bullet to go 100 yards. I just dont see anything with a wavelength shorter than a meter getting thru when the woods is wet. Parly this may be aggrevated with acid rain, which increases the conductivity of wet bark, leaves, and pine needles.

I know the lower frequency would mean fewer channels, but there aint that many of us living out here that that would be a problem.

Reply to
Day Brown

X-posted to a.i.w since stuff like this gets discussed sometimes.

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has several long range, (20 mi) data transmitters from 900 mhz on up to 5.4ghz... and running in the

90-200mw range.

I just dont get it. The FCC created a new experimental class such that you can use *any frequency you want* so long as its not over 200mw, and dont have forbidden antennas. But *nobody* is going to come out into the boonies to see if I or anyone else installed a 15db tuned yagi.

So- an OEM could offer 200mw data transceivers for 100-200mhz, without being liable for damages if users hook up 'illegal' antennas. So, why havent entrepreneurs already done it?

If a 56kbps modem can operate on the 3k bandwidth of POTS, then what would you expect the DTR to be on the 30k bandwidth of ordinary FM transmitters (which are available at 25$/ea at 200mw)?

Reply to
Day Brown

Show them the money and they'll do it. But apparently no one thinks there is a market. :)

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Try this link-

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Non line of sight wireless.

haven't actually used the system myself, but one of our vendors at $dayjob *swears* by these.

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