matteo@macbook:~$ iwconfig wlan0
wlan0     802.11b/g linked  ESSID:"cocorico"
          Mode:Managed  Channel=9  Access Point: 00:0F:3D:38:5B:7A
          Bit Rate=11 Mb/s   Tx-Power=26 dBm   Sensitivity:4/6
          Retry:on   Fragment thr:off
          Link Quality:0  Signal level:0  Noise level:0
          Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0

matteo@macbook:~$ iwconfig ath0
ath0      IEEE 802.11g  ESSID:"cocorico"  Nickname:""
          Mode:Managed  Frequency:2.452 GHz  Access Point: 00:0F:3D:38:5B:7A
          Bit Rate=11 Mb/s   Tx-Power:14 dBm   Sensitivity=0/3
          Retry:off   RTS thr:off   Fragment thr:off
          Power Management:off
          Link Quality=44/94  Signal level=-52 dBm  Noise level=-96 dBm
          Rx invalid nwid:51  Rx invalid crypt:0  Rx invalid frag:0
          Tx excessive retries:0  Invalid misc:0   Missed beacon:0