The ndiswrapper wiki gives you a good guide to follow to get it installed. You will have to use:
CODE
lspci
from a command prompt to find out the PCI-ID of your Atheros card. Then you'll have to check it against the ndiswrapper wiki database to find a good match. Then it will tell you which driver you should be using for your card. It's not always a case of using the Windows XP driver by default - although in my case, this has always been enough for me.
Try madwifi first, and go for ndiswrapper if you get nothing with madwifi. But follow the ndiswrapper wiki for installation. You don't need to follow the compile notes, since you've installed the Mandriva packages, but the instructions for installing the driver and going from there are what is most important. As I said though, try madwifi first if you haven't already.