Terrible signal strength in an office building

[t3h l337 n3wb]

I got a request from someone to set up some wireless access pointsto extend the range of an existing network. The location is a small office building, 2 floors with suites and stuff. My client wants to cover as much of the first floor as possible. Here's the current setup: the main router is a D-Link DIR-655 Draft N router with 3 big aftermarket antennas (not sure what kind/strength). I wired 2x75ft. Cat5e cables through the ceiling in 2 directions, hooking up D-Link DWL-G700AP access points to each cable. So it's like this:

AP1-------75ft-------Router-------75ft-------AP2

I'm sitting about 10ft. away from AP1 right now, and there's nothing in the way. However, the signal strength is extremely low (1 bar in Windows XP wireless zero utility). When I set it up the other day, I got an excellent signal from even farther down the hall, so I thought it was fine. Coming back today, though, I can't even see the SSID of AP1 sometimes. Originally, the DIR-655 was set on auto-scan channel, and the APs were set on channel 6. I've tried every single channel configuration, as well as swapping out the AP antenna for one of the big aftermarket ones on the DIR-655, but nothing seems to be working. Is there anything else I can do? I see like 6-10 other SSIDs around, so there seems to be a lot of noise. I'm on the phone with D-Link tech support now, but they're terrible and probably won't be able to help.

 

[spidey07]

Most likely noise if you can see that many others. Use netstumbler to find channel 1, 6 or 11 with the highest signal to noise and set the APs on different channels - 1, 6, 11. Also don't point the antennas at the client, they should be vertical.

Other than that if noise is still a problem you could use 5 Ghz or get somebody to do a site survey to locate the best place and kind of antennas to use as well as channel allocation.

 

[t3h l337 n3wb]

I already tried every combination of channels, and it didn't really help too much. Can I do anything else? If not, I guess I'll have to call someone else.