extentsion by a cable - is it possible ?

there is a free open wireless transmission next to my home.
if i step out of home w/my lappy i can connect to it easily.
but from inside my home it is coming and going.
it means that i already have a wireless card buit-in my laptop.
i wish to fulfill the following idea :
have a cable that is going from my room towards outside of the window where there is reception. (i.e. connected on the one side to the laptop and on the other side to some receptive device).
can you put my idea into words ?
(it just that i don't have any experience in these issues but ready to learn.
thnx guys
doronb