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160 km wifi signal

 Congratulations to Team iFiber Redwire for their 125 mile unamplified 802.11b link!





This was accomplished with a 12 foot dish on a mountain on the outside of Las Vegas and their remote station with a 10 foot dish on a mountain to the west of St. George Utah.
The team had spent much of their summer break from University to build and test their equipment. With surplus satellite dishes scrounged from their home area, building a custom trailer for the remote station, assembling all the scaffolding for the base station and testing. The teams talents in welding, mathematics, electronics, ham radio, programming, and Linux were all necessary to break their previous record.
I went up for the afternoon on Friday the 29th and Saturday the 30th, 2005 to watch these masters of technology.

Lightning was common in all directions during setup on Friday July 29th:


Two way voice communications over the 100 plus miles was made nearly effortless with the use of 2 meter ham radio gear.

A view in the aimed direction of the base antenna (over Las Vegas)


Topography of 124.9 mile WiFi link.


Path of 124.9 mile WiFi link showing the mountain height overcoming the Earth's curvature.


The only time they tried the amps was when the remote group was on a mountain in Utah 143 miles away but could not quite reach the desired coordinates 2 miles further and hundreds of feet higher, the road ended and the terrain was too rough to continue driving. They were a little too low in elevation, with a small mountain peak obstructing the two locations, they tried unamplified and amplified, and the 802.11b link would not work.

If they made it to the desired location, I'm confident that they would have successfully linked up at 145 miles.
The three images above created with Radio Mobile. My Radio Mobile presentation at SOCALWUG and the video.


Hand crafted antenna feed with circular polarization (can you say AO-40). Connected to
Z-Com XI-325HP+ 300mw PCMCIA cards in laptops running Linux.



Frequently Asked Questions:
What on earth do they need an amp for??

No amp was used in the 125 mile link. They tested the amps for about 10 minutes when the remote group was 143 miles away and this link did not work. Unfortunately the terrain would not cooperate. They had the amp on loan from a vendor. Also, the Z-Com PCMCIA card in Nevada was set to 300mw and the Z-Com PCMCIA card in Utah was set to 30mw.
Its just not fair that they called it "reliable", since they're blowing several retransmissions on every attempted send, so many, that I'm surprised the link works.

They deemed it "reliable" since it their applications, ssh to each other's Linux laptop, VNC etc. were up and running uninterrupted for several hours while they waited for the judges to arrive.
I can't even get my WiFI signal to reach my bedroom.
Install a 10' dish in your home :-)  You don't have Line Of Sight in your home nor do you have high quality antennas on your AP or laptop. Both of these factors may keep your signal from reaching you.
Isn't this too much power for WiFi?
All the members of the team are licensed Amateur Radio operators which allows much higher power.


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