This is my first HOWTO so please correct me if something goes wrong.
Today I purchased a PRONET PN-11NUSB wifi adapter in a hurry which is based on atheros chip. After googling a lot I managed to get it work.
Here are the steps:
I followed the initial steps from here but with slight difference.
1. Download the compat wireless drivers from here.
2. Extract the downloaded file
3. Now open the terminal and change directory to extracted directory
4. You will need to make the drivers.
e.g. $ cd ~/Downloads/compat-wireless-2.6.35-1/
4. Install drivers.
5. You need to install firmware for the drivers to work.
$ sudo make install
$ sudo make unload
$ sudo modprobe ath9k_htc
Download the firmware from here [Look for ar9271.fw].
6. Copy the ar9271.fw file to /lib/firmware
7. We are done!! cross check if your new hardware is installed correctly.
$ sudo cp /path/to/file /lib/firmware
$ sudo lshw