Would it be possible to amp a wifi signal from a hub to travel over 1.5 kilometres, and a wireless card signal to match it?
Yes, this would be perfectly possible. There are a few ways of doing it, you can channel all the power coming out of your device at the moment (which goes in every direction possible) and make it come out all in one direction. This will give you extra range but it obviously means that it is only good for point to point coms. Google for pringle can wifi if you are interested in this. It is also possible to get comercial arials but they are quite expensive. The other option is simply to boost the power of the transmitter. It is possible to buy these but if you use them in the UK you WILL be breaking the law, especially if you try and get to 1.5Km. I am not sure of the legality in other countries but my guess is that it is also ilegal. You can can use the pringles can with a booster, it will still be ilegal but less detectable if you are confining the signal to a beam. As you correctly say you will need something at either end to make sure that the comunication is not just one way. Rod
i don't think there is a limit for transmitting distance.. only transmitter power... I know there is some systems (network bridges) that can transmitt (legaly) up to 2 (or was that 20?) Km... You will need a directional antenna, but tjose are pretty easy to make.. (use google)... Mking an amp yoursef is wery difficult since we are handling HF signals in the GHz range here..
http://www.alfa.com.tw/product_wireless_06.htm. I read something about with clear sight point to point, it could reach...30KM's . Needs a good antenna though
I saw a DIY 802.11 amp a little while back - that would work as well, though a directional antenna sure would be easier.
I've built one of those Pringles can antennas, it's very simple to do. I've not gotten a chance to test it thoroughly, but when I do, I'll let you know how it does.
Use a WIFI calculator to check your power allocation, but off the top of my head, you'd be able to do just fine with 12dbi antennas at each end, you might even be able to go as low as 8dbi depending on your transmitter power. Try antenna suppliers like Pacific Wireless and SuperPass
