The Wilson stuff looks interesting. Sure wish there was a way to test whether or not there is anything to "boost" here.
Many phones have a way to get them to display the signal strength on a real "meter" rather than just the "bars" on the screen. On my Blackberry I can go into "options/status" and get the actual dB level of the signal. We're currently at a location at which the signal strength is extremely poor (-105 dBm) and the phones can't be used for conversation but out Wilson has had no problem maintaining a very decent internet connection.
Sandie & Joel
2000 40' Beaver Patriot Thunder Princeton--425 HP/1550 ft-lbs CAT C-12
2009 Chevy Malibu LTZ with ReadyBrute tow bar/braking system
Official WiFiRanger Ambassador WFRAMB303
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While a bigger antenna and/or amp cannot improve zero reception, the lack of service on your cell phone MAY not mean zero signal. However, you'll have to spend some money to find out.
Since this is for a cabin, I would not necessarily go with the (superb) wilson trucker--it is a MOBILE antenna. Go to "l-com.com", where you can find carrier-grade antennas and amps.
Others have provided links to learn about antennas. If I were in your shoes, and a cell phone could pick up signal 1 mile away, I would bet some money and effort on it. If you're in a remote area, you could even stick a repeater antenna up a tree on a hill, powered by a solar panel.