Open the Terminal. Applications--> Accessories--> Terminal OR press ALT+F2 and type 'gnome-termianl' & enter then you have to check the WiFi adapter so type , lspci -v , in the terminal and check wether your adapter is Atheros and if not i'm afraid that this might not work, so after knowing that it's Atheros you can proceed further
System-->Administration-->Hardware Drivers and Deactivate the driver Ubuntu has used for the adapter (in most scenarios Ubuntu assigns a avalible driver for the adapter but it's won't be competible )after that reboot .
The kernel headers and the compiler are needed to build this driver so you have to get started by installing build-essential. In a terminal window (Applications/Accessories/Terminal) enter:
sudo apt-get install build-essential
The driver code will be downloaded with the subversion source code manager so I installed subversion:
sudo apt-get install subversion
You need a place to put the driver source without mixing it up with other stuff so changed directory to your home directory:
Created a directory:
And changed to the new dirctory:
Use subversion to download (checkout) a copy of the code: If this site is not working mail me ..I have the tar file....
After the driver code is downloaded by subversion, change to the directory, which should be madwifi-hal-0.10.5.6
Run the make script to have the compiler build the driver:
Install the driver
sudo make install
sudo make && make install
Add the Atheros kernel module to the list of modules to be automatically loaded at boot by adding "ath_pci" (without the quotes) to the end of the /etc/modules file. Gedit is probably easy to use so try:
sudo gedit /etc/modules
Now you can reboot and it should work.