[CentOS] Wireless problems

Hi guys, I have a problem with my Centos 6.4.

I am experiencing a Wireless Disconnects, some time ago I had them
constantly each 2-3minutes. After upgrading to new kernel (and other
software from "Software Update" I am still exepriencing disconnects but
every 10-15 minutes. It makes me angry because I am doing a lot of work
with ftp servers.

Card:
*Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express)
(rev 01)*

uname -r:
*2.6.32-358.23.2.el6.i686*

I Turned off ipv6 in */etc/sysctl.conf*

Here is Log: ( I divided it into 2 stages)
----------------------------------------------------
Nov  8 14:10:01 mlody kernel: cfg80211: Calling CRDA to update world
regulatory domain
Nov  8 14:10:01 mlody NetworkManager[8817]: <info> (wlan0): supplicant
connection state:  completed -> disconnected
Nov  8 14:10:01 mlody kernel: cfg80211: World regulatory domain updated:
Nov  8 14:10:01 mlody kernel: cfg80211:   (start_freq - end_freq @
bandwidth), (max_antenna_gain, max_eirp)
Nov  8 14:10:01 mlody kernel: cfg80211:   (2402000 KHz - 2472000 KHz @
40000 KHz), (300 mBi, 2000 mBm)
Nov  8 14:10:01 mlody kernel: cfg80211:   (2457000 KHz - 2482000 KHz @
20000 KHz), (300 mBi, 2000 mBm)
Nov  8 14:10:01 mlody kernel: cfg80211:   (2474000 KHz - 2494000 KHz @
20000 KHz), (300 mBi, 2000 mBm)
Nov  8 14:10:01 mlody kernel: cfg80211:   (5170000 KHz - 5250000 KHz @
40000 KHz), (300 mBi, 2000 mBm)
Nov  8 14:10:01 mlody kernel: cfg80211:   (5735000 KHz - 5835000 KHz @
40000 KHz), (300 mBi, 2000 mBm)
-------------------------------------------------------
Nov  8 14:10:01 mlody NetworkManager[8817]: <info> (wlan0): supplicant
connection state:  disconnected -> scanning
Nov  8 14:10:17 mlody NetworkManager[8817]: <info> (wlan0): device state
change: 8 -> 3 (reason 11)
Nov  8 14:10:17 mlody NetworkManager[8817]: <info> (wlan0): deactivating
device (reason: 11).
Nov  8 14:10:17 mlody NetworkManager[8817]: <info> (wlan0): canceled DHCP
transaction, DHCP client pid 16791
Nov  8 14:10:17 mlody NetworkManager[8817]: <warn> Couldn't disconnect
supplicant interface: Method "Disconnect" with signature "" on interface
"fi.epitest.hostap.WPASupplicant.Interface" doesn't exist#012.
Nov  8 14:10:17 mlody NetworkManager[8817]: <info> Auto-activating
connection 'Auto Bulgarski Poscikk'.
Nov  8 14:10:17 mlody NetworkManager[8817]: <info> Activation (wlan0)
starting connection 'Auto Bulgarski Poscikk'
...


first block: This appears and after several seconds then second block
appear and the wifi is disconnected, right after it disconnects it tries to
reconnect.


*Regards!*