"Adair Witner" <buhbear007@mail.com> hath wroth:
>Hi, first time poster but I have been reading for awhile.
I just post answers. Some day, I might get around to reading the
questions.
>What I want to do is link myself and a friend that lives a block away in
>another apartment complex.
Ummm... 680ft is a bit more descriptive than "a block".
>See http://kd5dyp.mine.nu:8081/wifilink.jpg for a picture of the link.
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.
>I am Link 1 and I have a WRT54Gv3 running DD-WRT and a 19db omni.
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.
>They are Link 2 and have a WRT54Gv5 stock antennas.
The stock antennas are only about 2dBi gain. Probably not enough to
get a reliable connection. Run the link calcs at:
|
http://wireless.wikia.com/wiki/Wi-Fi#Link_Calculations
and 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.
>I sit at ground level at my apartment with the omni sitting in the window
Replace 19dBi omni with patch, panel, yagi, or other directional
antenna. Indoors is not a good place for a high gain omni.
>They are on the 4th floor with a balcany..
Do they have line of sight? That means can you see your window. Any
trees?
>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
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.
>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.
Buy two panel antennas and replace the omni at your end.
>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.
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).
>Once I get the RF link made I can handle the rest just wondering what the
>cheapest and easyest way might be..
Do the math to see how big the antennas will need to be.
--
Jeff Liebermann
jeffl@comix.santa-cruz.ca.us
150 Felker St #D
http://www.LearnByDestroying.com
Santa Cruz CA 95060
http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558
Bridging 
Linear Mode
