wireless setup

I have set up sattelite broadband due to no access to cable or dsl in my
area. and then added a d- link wireless router with d link pcmia card for my
laptop it is working fine in my house with ecellent signal. ( i have set up
the aerial for router at window when i bring my laptop outside to a
portacabin roughly 50 ft from the window i t show ok-good signal but says
limeted or no connectivty icon. Any ideas what would be wrong and is there
any way i could boost the signal any way just to give me a mors stady
reception.

Many thanks in advance for any help




Loupier