reminds me of that 72-mile WLAN link from san diego to the san clemente islands. http://www.computerworld.com/mobiletopics/mobile/story/0,10801,76118,00.html http://computerworld.com/mobiletopics/mobile/story/0,10801,75830,00.html quote: 'Ma agreed. He said 72 miles "is a truly amazing feat," especially over water, where reflections can inhibit the signal.'
You might be able to ask them about water issues first hand. http://hpwren.ucsd.edu/ Chris ----- Original Message ----- From: "Jeff Kutz" <[EMAIL PROTECTED]> To: <[EMAIL PROTECTED]> Sent: Thursday, September 11, 2003 3:04 AM Subject: Re: [SOCALWUG] WiFI over water > When I first got interested in the subject of WiFi, I read about a link, I > believe it was in Hawaii, where they went some 20+km over water. They had a > picture from one of the sites and it looked like they were quite high over > the water. It looked like they were going from a hill/mountain to another > hill/mountain. They didn't report any water-specific problems. They did use > a hi-gain antenna but the idea was the long range of the link so this is to > be expected. > > I would say, "Go for it, and report back....." > > regards, > > Jeff > > > > >From: Andy Middleton <[EMAIL PROTECTED]> > >Reply-To: [EMAIL PROTECTED] > >To: SOCALWUG <[EMAIL PROTECTED]> > >Subject: [SOCALWUG] WiFI over water > >Date: 11 Sep 2003 09:23:15 +0100 > > > >Jack, > > > >Another small challenge! I'm planning to make a 3 or 4 km link over the > >sea across a small bay here in Tenerife. One side of the link is fairly > >high (40-50m above sea-level), but the other is at half the height > >(20m). In theory I am not infringing the Fresnel zone (at 3 miles is > >almost 8m), but I am slightly concerned over possible reflections from > >the sea. I know that normally water absorbes microwaves, so I don't > >think it will be a problem, but I wondered if, on those days of > >dead-calm, there could be any reflection; the signal is almost parralel > >to the water, I am using horizontal polarisation: what is the worst that > >could happen to the link? > >Now that we're talking about it, how low can I go with my link? What > >would happen with vertical polarisation? Are there any "water-effects" > >that I have to be especially aware of? That I can even take advantage > >of? Could one "reflect" ALL of the signal? WOuld that be usefull? > > > >Sorry if its abit long! > > > >Andy Middleton > > > > _________________________________________________________________ > Express yourself with MSN Messenger 6.0 -- download now! > http://www.msnmessenger-download.com/tracking/reach_general >
