Seattle to Portland Link?
Hi:
Sam Churchill here. I'm a member of Portland's PersonalTelco and am the editor of a daily weblog called Daily Wireless.
What do you think of Creating a Seattle to Portland link.
The 5.8 GHz band can output 200 watts EIRP, point-to-point. That's a reliable 30 miles. OFDM might handle multi-path interference. Equipment will get faster, better, cheaper. At some point - perhaps next year when affordable, off the shelf 802.16a equipment is available - this concept is going to look increasingly practical.
You'll have uncoordinated groups all coming up with their own proposals. I'm suggesting a coop. It would be dedicated to non-commercial and scientific applications. Not commercial applications. It could enable larger files - perhaps video files or earthquake telemetry - to be exchanged between Portland and Seattle. It might also enable hot spots in rest stop kiosks. That could create a revenue stream for the non-profit network.
How practical is this:
A Portland to Seattle link might hop from:
- Portland to Mt St Helens (60 miles)
- Mt. St Helens to Mt Rainier (60 miles)
- Mt Rainier to Seattle (60 miles)
The Mt St Helens link could go the visitor's center. A CraterCam (with a camera INSIDE the crater) would link to it. Each relay point could be stuffed in an Igloo Ice Chest.
Maybe a Soekris box or a similar solid-state, dual-card unit would work. There's tons of dark fiber on the I-5 corridor, of course and Northwest Microwave has a system that focuses on the Northwest. But none goes up the mountain.
The Redline AN-50 supports up to 8 channelized T1 circuits. If a Seattle/Portland T-1 cost $100/month, that would generate about $10K/year, for all 8 lines. It could be a self-sustaining. The USGS, schools, weather bureau and others could be coop partners. SeattleWireless and PersonalTelco might contribute in-kind expertise in exchange for a "free" T-1.
The 5.8 GHz band might work. The power limit is 1 watt but there is NO limitation (on Point-to-Point) until a maximum of 200 Watts EIRP is reached. A 60 mile long shot might be practical with 5 GHz and 1 watt amps.
Maybe ten relays strung every 20 miles or so down the I-5 corridor would make a practical, inexpensive, emergency backbone. You'd need something like Karlnet, or better yet, 802.16a. I don't know if these kinds VERY long relays would be practical but it wouldn't cost much to find out, would it.
Federal bucks will install 5.9 GHz ITS relays to connect weigh stations and highway readerboards. Weather, police, fire, schools and tourist information offices might piggyback on the ITS network at 5.8 GHz. They'd hit the rest stops.
A SeattleWireless/PTP link would be dedicated to non-commercial use. Relays at I-5 rest stops or at geologically strategic Access Points at Mt Hood, St. Helens and Rainer could deliver useful, low-cost alternative to phone lines.
I don't know what cost, application, latency, management and reliability issues might be show stoppers. Still, using the unlicensed 5.8 GHz band with gear like Redline or other vendors, a cooperative Seattle/Portland link might make sense.
- Sam Churchill
- --
This sounds like an interesting project. I was thinking of doing something similar up here in Newfoundland at old amature radio repeater sites, At one point all the repeaters accross the island were linked up and one could talk to someone in St. Johns, which is around 700km away.
We were thinking of using 802.11b and a pair of wireless ethernet bridges to create something like a cross band repeater. One of the briges would be on channel 1 pointing east and the other on channel 11 pointing west and the next site would be the otherway around. We would use old 39inch starchoice satellite tv dish's which would give us well over 25db of gain.
Anyway I don't think you need to go crazy with power if you have big enough dish's. But the problem with dishes is windloading, I don't know what the wind is like on the mountains around Seattle but up here we are looking at up to 200km/h at peak and 100km/h regually.
--
ChrisMcDonald, VO1 CSM
Yeah, it would be quite a project, Chris.
I just got a note from Eric Kozowski who clued me in on evergreenintertie.com and lloydio.com/evergreen.html, the ham radio network.
Here's a map:
- Sam Churchill www.dailywireless.org
