Wireless network setup question

[Fandu]

Since DSL is not available to either my house or my friends house, we're trying to see if it's possible to do a wireless link from the closest place that has DSL which is 1 mile from my house, and 2 miles from my friends place. I've drawn up a
map of our plan that I wanted to run by you guys and see what comments you had.

We want to run a 1.4mbit DSL connection from a place called MCDC using a linksys wrt54g router and a 16-slot waveguide antenna to both of our houses. We're planning to each use ~14dBi dipole antennas with wrt54g's in client mode. We're planning to use one of the custom firmware available for the wrt54g's so we can run them in client mode. Our first question is will the system work as we want: 1) provide both of us with broadband and 2) bridge our LAN's so we can share files.

 

[alexXx]

if you have no trees or anything in the way, then it will most likely work

 

[JackMDS]

If the Antennae are Good and are installed High above the Ground so there is No obstructions (clear line of sight) it might work.

You would need an instrument to do the Antenna?s alignment since from such a distance you can not do it by Sight.

:thumbsup:

 

[Fandu]

Both my friend and I have line of sight to the source antenna. We are able to mount all of the antennas ~20' off the ground.

 

[alexXx]

if you have the money, go for it. that would be a neat project(i am actually currently hooking my grandparents up to my network,(1/4mile away) using a home made cantenna and an old satelite dish.

 

[sjgmoney]

Sounds like a cool idea, however I have the feeling that line of sight from 100 yards is one thing, from 1 or 2 miles is another. You may think you have things lined up......

JackMDS is probably on to something here, you're going to need help lining up the antennas.

 

[Cheetah8799]

You may want to check out the MeshAP project to get some antenna ideas. http://www.locustworld.com/

They have a mailing list which some very smart folks participate in. You could ask for antenna suggestions there.

2 miles is a long way, so you may need to get creative with your antenna if you want it to work. Or just spend a lot of money. I believe there is a way to build an antenna with a coffee can so that the antenna signal will be focused in one direction, as opposed to all around. That way you can get optimal signal from point to point. Also, keep in mind that weather conditions will likely affect your signal quality at 2 miles.

 

[ktwebb]

Two miles isn't that far if you have the right equipment and know what your doing. An omni dipole on your end however is not what your going to want to use. Yagi or parabolic, and you don't need near that much gain on the radiator for that distance, assuming of course you have clear unobstructed line of sight and good fresnel zone clearance. With a 16 dB waveguide on the other end, and IF it is setup correctly, you could get away with something in the 7 to 9 dBi range with a moderately narrow beamwidth on your directional. Low loss cable, depends on how far the run is to determine what kind you need, and properly grounded with lightening arrestors. Could do it in my sleep but if I had never done this before then I'd have a slim chance of making it work properly. Do-able but dificult. As far as the pointing, you don't really need anything but good software and good sense. Panning with a strength utility can be tiresome and frustrating but generally it's a pretty easy thing to do in concept and practice.

 

[Fandu]

The guys at Sveasoft are suggesting using 14.2dBi panel antennas at all 3 locations. I can get a decent price of $54cdn /panel with 3' LMR195 & RP-TNC to fit WRT54G from Superpass, so that might be what we try and do. What kind of signal strength do you think we could get from that?

 

[ktwebb]

What's the beamwidth on those antennas?

How are you going to mount your antennas? You mentioned in an earlier post about mounting at 20' but you only mention 3' of transmission cable in this last post. Not adding up unless your going to run ehternet to the bridge mounted on the mast, and then the 3' pigtail to the antennas. That's plenty of juice for that distance assuming your parent bridge/antenna has the proper beamwidth to accomodate both remote sites. I would use yagi's at the remote sites myself. Would be cheaper I'd think, and possibly a more directed pattern. I don't know. I have just never been a fan of panels but they may be just the trick for you.


Edit:
I just looked and saw some panels with a 17 degree beamwidth. That's fine. Might want to go a bit wider at the parent site. 23 degrees or something like that. Hard to say based on a drawing.
As far as strength. All things being perfect (meaning pointing/panning, cabling/crimping, etc...) 100%. Only reason besides being done poorly would be interference and you wouldn't know that for sure until you got it up, or at least did some detailed surveying.

 

[Fandu]

ktwebb: The plan is to mount the AP's on the mounting bracket and run power-over-ethernet down to the respective networks. As far as the beam width goes, I ran some quick calculations today and the houses are around 8 degrees apart when looking from the parent site. So the 14dB panel has a 27 degree beam, and the 18dB'er has a 17 degree beam so I think either of them would work just fine. We're going to take some GPS readings to get an exact number though.

 

[JackMDS]

Do not forget Grounding.

You have to put the APs in Weather protected boxes and make sure they can vent excess heat.

 

[Fandu]

We're on it. We have some outdoor electrical boxes that we're planning on using.

 

[ktwebb]

And lightening arrestors. They will need to be arrested as well as grounded. With only 3 feet of LMR195 you'll have very little loss for the cable run. You'll have to factor in some extra cable for the lightening arrestors and connectors for them.