EDIT: Ubiquiti Bullet2 was the solution. One of those on each end and the speed is great now (it is now faster than the internet connection, and thats all that matters to us)
Hello,
I have recently set up a 3.7 mile wireless link between two locations. We are using a Linksys WAP54g with firmware 3.04 on each end. They are on a clear channel, in bridge mode, and using WEP encryption. For antennas, we have 24db grid antennas from hyperlink. There is excellent line of sight and no fresnel zone problem. The cable run from the access points to the antennas is 11 feet, using hyperlink coax.
The connection is stable, but the tested speed readings are only 600-800kbps.
The first thought was that it might not be enough power, so we installed 1 watt 802.11g amplifiers (also hyperlink). This added 10 feet to the cable length. Unfortunately, speeds did not change significantly (possibly a little bit lower speed actually). We have since tried changing all sorts of settings on both access points, with no visible difference in connection speed.
Can anyone identify what is going wrong with this setup? What really confuses me is that the amplifiers did not help the speed at all. Is there a setting we should change? Is there a better firmware for the job?
Has anyone actually been successful in obtaining 3-4mbps+ speed at this distance without buying $10,000 pro hardware?
Last edited by bp2008; 01-28-2009 at 02:31 AM.
Reason: Update
That end is in the process of acknowledging receipt of a previous packet.
Both ends wait a while.
This end sends another packet...
Now that end has to acknowledge receipt of two packets.
All of this back and forth is happening on one channel. Much listening and waiting and acknowledging and deferring. And colliding. All of which takes time.
Which slows the throughput.
The need to acknowledge receipt of packets on the same link is what's holding you back.
Thank you for your response. I have seen on wikipedia that 1 mile is usually the maximum distance. (Long-range Wi-Fi - Wikipedia, the free encyclopedia) I don't think the WAP54g has this particular setting though, does it? Is there perhaps a stable third party firmware that does have this parameter?
Just to help you feel real bad about all this I have used Inverted homemade 7 Sector Amos antennas (in horizontal polarisation mode) running off Belkin 7001 wireless cards in Ad-Hoc mode over 8.67km's.
Connection speed? - between 7 - 8Mbits both ways.
Total cost of antenna's (excluding my retirment time!) - around £20!
Distance between wireless cards and antenna (on both sides0 using RG58 cable was approx 4meters.
The wireless cards? - old stuff nowadays, you couldn't give them away of you wanted too.
So - is it possible? Yes it is, and for what ever reason, you have some real bad timing/delay issues - which I agree with mark, are more than likely settings as opposed to poor hardware.
Just to help you feel real bad about all this I have used Inverted homemade 7 Sector Amos antennas (in horizontal polarisation mode) running off Belkin 7001 wireless cards in Ad-Hoc mode over 8.67km's.
Connection speed? - between 7 - 8Mbits both ways.
Wow. I am impressed. If you can do that with homemade antennas and older hardware over a longer distance, then it has to be possible to improve the speed in my case!
When you get to understand whats involved in the making of an antenna, you realise that by and large mass produced antenna's are crap - homemades (made properly for a given situation) almost always perform better.
I will keep that in mind about homemade antennas, next time I need one.
Anyhow, I came across the Ubiquiti Bullet2, which seems like exactly the answer I was looking for. Two of them are on the way, and hopefully better speeds along with them. Fortunately, I have other uses for the Linksys APs, so they will not be going to waste.
The Ubiquiti Bullet2 did the trick (it automatically sets the timeout for frame acknowledgement). Including the POE injectors, it was about $60 each. The speed is now where it should be, and I have a new favorite network hardware manufacturer.
I'm kinda curious how you came across the Ubiquiti Bullet2 to think it would cure your speed problem? I believe it worked because you said it did but after visiting the Ubiquiti site, nothing jumped out at me to indicate that the Bullet2 would fix your problem. Did you talk to a tech person? What speed did you finally get out of the system? Thanks.
3.7 Mile 802.11g speed disappointing 
Linear Mode
