I got a Motorola Atrix and..... ?

I just got a Motorola Atrix and it has terrible signal where I live. We have had problems with certain phones in this area. I upgraded from my Samsung Mythic, which got good signal (not the best but I could send a text almost anywhere). The lady at the AT&T store said this phone should be a bit better. I tried an iPhone because that was my other choice of phone. It got good signal at first but then lost it after it actually made a call. So does this phone have an antenae on the back so I could try the twist tie trick?