sudo modprobe ath_pci
sudo iwpriv ath0 bgscan 0

   5.

      Edit the rc.local

sudo gedit /etc/rc.local 

and add

iwpriv ath0 bgscan 0 

just before the

exit 0 

and save. (This prevents the "wifi0: rx WIFI overrun" bug [WWW] #1017)

Finally, the atheros driver will prevent you from resuming after suspend-to-ram, so edit /etc/default/acpi-support and add the ath_pci driver to the MODULES variable:

MODULES="ath_pci"