Wireless Connection Drop out

Hello all, I have a D-Link wireless router with a pc with a wireless netowrk card in it but after the pc sits a while with no activity it loses it connection but I have apps on it that require it map network drives so I am getting alot of errors due to the lost of connectivity is there any quick fix out there that will keep that connection with out killing alot of band width or pinging my router to death??

Thanks

DEE