First of all this is not a general Linux forum, if you read the Wiki you will see that Backtrack requires advanced Linux skills.
Also if you do some research you can actually see that athk9 works with injection and your card is also supported, Backtrack should work without any driver installation problems:
http://www.backtrack-linux.org/forum...85-driver.html
http://www.backtrack-linux.org/wiki/..._working_cards
http://forum.aircrack-ng.org/index.php?topic=5927.0# Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01) - using the mac80211 ath9k drivers-passed
http://forum.aircrack-ng.org/index.php?topic=8530.0
http://forum.aircrack-ng.org/index.php?topic=7438.0


