Probleme wifi

Bonjour, à tous
je suis vraiment decu de linux unbuntu
j'espere que ce serait simple
mais voila je galere a me connecter en wifi j'ai installer unbuntu 9.04 sur netbook
N140 avec seven dessusj'ai installer les pilotes qu'il fallait la connexion marche
mais au bourt de 5 ou 10 min et le taux ne depasse jamqis les 47% meme en etant à cote de la free
déconnexion impossible de se reconnecter obliger de redémarrer
alors que sous seven je n'ai pas de probleme

voile aussi les resultats des commandes à effectuer
pour avoir toutes les inforamtions necessaires aux personnes qui connaissent pour moi
c'est du chinois

barkaoui@LittleWing:~$ cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=9.04
DISTRIB_CODENAME=jaunty
DISTRIB_DESCRIPTION="Ubuntu 9.04"
barkaoui@LittleWing:~$ lsusb
Bus 001 Device 003: ID 0ac8:c33f Z-Star Microelectronics Corp.
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 005 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 004 Device 002: ID 0a5c:2151 Broadcom Corp.
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub

barkaoui@LittleWing:~$ lspci
00:00.0 Host bridge: Intel Corporation Mobile 945GME Express Memory Controller Hub (rev 03)
00:02.0 VGA compatible controller: Intel Corporation Mobile 945GME Express Integrated Graphics Controller (rev 03)
00:02.1 Display controller: Intel Corporation Mobile 945GM/GMS/GME, 943/940GML Express Integrated Graphics Controller (rev 03)
00:1b.0 Audio device: Intel Corporation 82801G (ICH7 Family) High Definition Audio Controller (rev 02)
00:1c.0 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port 1 (rev 02)
00:1c.2 PCI bridge: Intel Corporation 82801G (ICH7 Family) PCI Express Port 3 (rev 02)
00:1d.0 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI Controller #1 (rev 02)
00:1d.1 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI Controller #2 (rev 02)
00:1d.2 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI Controller #3 (rev 02)
00:1d.3 USB Controller: Intel Corporation 82801G (ICH7 Family) USB UHCI Controller #4 (rev 02)
00:1d.7 USB Controller: Intel Corporation 82801G (ICH7 Family) USB2 EHCI Controller (rev 02)
00:1e.0 PCI bridge: Intel Corporation 82801 Mobile PCI Bridge (rev e2)
00:1f.0 ISA bridge: Intel Corporation 82801GBM (ICH7-M) LPC Interface Bridge (rev 02)
00:1f.2 IDE interface: Intel Corporation 82801GBM/GHM (ICH7 Family) SATA IDE Controller (rev 02)
00:1f.3 SMBus: Intel Corporation 82801G (ICH7 Family) SMBus Controller (rev 02)
02:00.0 Network controller: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) (rev 01)
03:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller (rev 02)

barkaoui@LittleWing:~$ lspci -nn | grep -i net
02:00.0 Network controller [0280]: Atheros Communications Inc. AR9285 Wireless Network Adapter (PCI-Express) [168c:002b] (rev 01)
03:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8101E/RTL8102E PCI Express Fast Ethernet controller [10ec:8136] (rev 02)


barkaoui@LittleWing:~$ sudo lshw -C network
[sudo] password for barkaoui:
*-network
description: Wireless interface
product: AR9285 Wireless Network Adapter (PCI-Express)
vendor: Atheros Communications Inc.
physical id: 0
bus info: pci@0000:02:00.0
logical name: wmaster0
version: 01
serial: 00:26:b6:53:7f:7e
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress bus_master cap_list logical ethernet physical wireless
configuration: broadcast=yes driver=ath9k latency=0 module=ath9k multicast=yes wireless=IEEE 802.11bgn
*-network
description: Ethernet interface
product: RTL8101E/RTL8102E PCI Express Fast Ethernet controller
vendor: Realtek Semiconductor Co., Ltd.
physical id: 0
bus info: pci@0000:03:00.0
logical name: eth5
version: 02
serial: 00:24:54:13:41:5b
size: 100MB/s
capacity: 100MB/s
width: 64 bits
clock: 33MHz
capabilities: pm msi pciexpress msix vpd bus_master cap_list ethernet physical tp mii 10bt 10bt-fd 100bt 100bt-fd autonegotiation
configuration: autonegotiation=on broadcast=yes driver=r8169 driverversion=2.3LK-NAPI duplex=full ip=192.168.0.24 latency=0 link=yes module=r8169 multicast=yes port=MII speed=100MB/s
*-network DISABLED
description: Ethernet interface
physical id: 2
logical name: pan0
serial: 0e:13:47:ac:1a:44
capabilities: ethernet physical
configuration: broadcast=yes driver=bridge driverversion=2.3 firmware=N/A link=yes multicast=yes
barkaoui@LittleWing:~$