Wifi rf question

Post by **harrisjt2000** » Sun Nov 12, 2006 7:30 pm

ok, i have a some property at aprox .802 NE (map below) of me and there is no dsl or highs speed located there my question is i have some roam abouts and i may have a couple of 1 watt bridges, i can talk back and fourth from my location here to the other location with true FRS radios just fine and i can really talk with my xts3000 to the other on grms. but what i want to know is if i get some high gain antennas could i shoot wifi back and fourth easily? i have a tower on both propertys but one is below the tree line and the other is almost the same. there is a map below to show what i want i painted in where trees are. if any one has a sugestion please let me know. and any recomended soulutions i have no clue about the 2.4ghz band and what it can and cant do

tvsjr · Post by **tvsjr** » Sun Nov 12, 2006 7:48 pm

You need direct line of site... if you can do that, a couple of 1-watt units and a yagi or paraflector on each end would work just fine.

Post by **harrisjt2000** » Sun Nov 12, 2006 7:52 pm

ok thanks i could probally get it to Line of sight. 2.4 ghz doesnt go through trees and such that well i take it

AEC · Post by **AEC** » Wed Nov 15, 2006 12:03 pm

Seeing that your location is under 1 mile, and aside from a 'line' of trees along your intended path, I would get a high gain yagi and Heliax for use and I'll bet you would have no problems.

Free space path loss is minimal at < 1 mile, and 'if' the AP is using a good antenna as well, the link budget should work as long as the actual noise floor can be kept low enough.

Linksys or NetGear?

There are programs available that allow you to 'crank up' the output levels without damage, but you also need to hear the AP also.

Yagis are the easiest way to go. 10+ elements at S-Band should give you a strong, almost pin point accuracy signal to that AP.

If you were farther than a mile, or had large structures in the path, then i might suggest a link of sorts, but under a mile, the simplest solution would be a high gain yagi and heliax or similar cabling.

Remember, 2.4 Ghz. IS lossy, especially with 'standard' coaxial cables.

Forget ANY RG types, as well as 9913 water hose cable.

Times LMR400/600 might be the lowest cost you can get away with, but with no margin for error.

Don't forget that you will be working with signals generated at well under 1 watt ERP at the AP, so what you will receive will be closer to -90 Dbm or lower, like -110....That's pretty weak.

If you have the ability to check the signal levels through your equipment, do so while aligning your antenna, or have a friend point the antenna while you indicate the best direction/signal level via HAM RADIO, of course!

aaknitt · Post by **aaknitt** » Sat Nov 18, 2006 3:50 pm

The Green Bay Packet Radio guys have an online calculator that might help you out. It's pretty extensive (almost overkill).

http://my.athenet.net/~multiplx/cgi-bin ... s.main.cgi

If tree loss ends up being too much to overcome, you could consider 900 MHz, which is slower and would require new gear, but would handle the trees better.

Andy

mr.syntrx · Post by **mr.syntrx** » Sat Nov 18, 2006 11:43 pm

tvsjr wrote:You need direct line of site... if you can do that, a couple of 1-watt units and a yagi or paraflector on each end would work just fine.

100mW with direct line of sight and high gain antennas will do it, with no trouble at all.

Birken Vogt · Post by **Birken Vogt** » Thu Nov 23, 2006 11:55 am

mr.syntrx wrote:100mW with direct line of sight and high gain antennas will do it, with no trouble at all.

Sounds like you say that from experience, what sort of feed line are you referencing and how long on each end? Antennas and connectors?

Birken

CTAMontrose · Post by **CTAMontrose** » Thu Nov 23, 2006 5:57 pm

your distance shouldnt be a problem at 2.4GHz. We have some 802.11A (5ghz) links that are farther than that.. of course they are on 6' dishes, but at your distance, even a 2' dish would have more than enough fade margin.

Feedline loss can be drastically reduced by tower mounting the radio near the antenna as well, of course this approach will require some creativity for power and making the system environment proof.