Atheros Ar9286 Need Fastest Best Reception Wifi Adaptor For A Wireless Laptop?

Need fastest best reception wifi adaptor for a wireless laptop? - atheros ar9286

Hello I have a Sony VAIO VGN ns325 to a wireless network adapter Atheros ar9286 (Vista) I can not run a good reception in many areas where there is no open-Fi ... Proposals to improve performance or is it better, faster, stronger I install the WiFi card in my laptop? Thanks