I have been using a cell signal amplifier for about 1 month now and so far very satisfied. It took a few days to setup since the directional antenna should point to the tower. I purchased theSIG-008from Signifi (
http://www.signifimobile.com/). There are many different models so you may select what works best for you. Their price is reasonable andwhat did it for me wasthe 60 day return policy so I knew that if I had issues making this work it could be returned.
My current positionhas virtually no signal, phone kept dropping the connection. So if you have any signal at all, then this should probably work. The amp also works with data (via the cell connection)as well, in fact this reply is going through the amp to get to the internet.
If I can provide additonal info, just send me an email off-line.