Bridging

Hi, first time poster but I have been reading for awhile.

What I want to do is link myself and a friend that lives a block away in another apartment complex. See

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for a picture of the link. I am Link 1 and I have a WRT54Gv3 running DD-WRT and a 19db omni. They are Link 2 and have a WRT54Gv5 stock antennas.

I sit at ground level at my apartment with the omni sitting in the window They are on the 4th floor with a balcany.. If I go to my friends house, from their balcany (on the 4th floor) I can see my network if I hold the laptop out over the rail I plan on purchasing a flat panel wifi antenna and mounting it on their balcany so that it is standing out away from the building somewhat. The options I have looked at: Wireless bridge with external antenna (like the WET54g or similar) attached to the flat panel. WRT54GL with DD-WRT in Client Bridge (which works well) or some other option with the radio mounted in the back of the antenna running PoE. Any suggestions? Once I get the RF link made I can handle the rest just wondering what the cheapest and easyest way might be..

TIA, Adair

Reply to
Adair Witner
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"Adair Witner" hath wroth:

I just post answers. Some day, I might get around to reading the questions.

Ummm... 680ft is a bit more descriptive than "a block".

Should be doable. I see some potential problems:

  1. You're shooting across the face of the apartment building. This is tricky as you're going to have some blockage in the Fresnel Zone. At midpoint, you need about 7ft radius about the line of sight.
  2. I can't tell if there are any trees in the way from the photo. If there are trees, the signal loss is substantial.

Such an antenna would have a very narrow vertical radiation pattern of about 10 degress. Slight changes in tilt angle will result in huge changes in signal strength. A 19dBi panel or dish would be more appropriate.

The stock antennas are only about 2dBi gain. Probably not enough to get a reliable connection. Run the link calcs at: |

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see how much fade margin you're working with. My guess is that it's not enough with the stock antennas.

Incidentally, I just replaced my BEFW11S4v4 router with a WRT54Gv4 with DD-WRT at my house. The WRT54G does not appear to have a very good receiver and I've lost some coverage area.

Replace 19dBi omni with patch, panel, yagi, or other directional antenna. Indoors is not a good place for a high gain omni.

Do they have line of sight? That means can you see your window. Any trees?

Yeah, it appears that the building is in the way. How far out can you cantilever a direction antenna? I have such a system between two offices in the same building. Shooting across the face of the building was quite a challenge. I had to attach a 4ft PVC pipe to the outside of the buildings for the panel antennas to make it work.

Buy two panel antennas and replace the omni at your end.

I would use two panel antennas, some LMR-240 coax cable, and a pair of WRT54G routers with DD-WRT. That will avoid having to waterproof the radio or tinker with PoE. It would appear that you're only going to have about 6ft or so of coax, which can easily be tolerated (0.13dB/ft for LMR-240).

Do the math to see how big the antennas will need to be.

Reply to
Jeff Liebermann

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