Wavemon

Configuration

Use iwconfig to check if your wireless adapter is recognized

To install Wavemon use the following command :

sudo apt-get install -y wavemon

start using the following command

wavemon
iwconfig
which will give you something like :
wlan0 IEEE 802.11bg ESSID:"TheMatrix" Nickname:"XXXXXX"
      Mode:Managed Freq:2.427 GHz Access Point: 00:18:4D:10:49:C6
      Bit Rate:54 Mb/s   Sensitivity:0/0
      Retry:off   RTS thr:off   Fragment thr:off
      Power Management:off
      Link Quality=98/100 Signal level=83/100 Noise level=0/100
      Rx invalid nwid:0  Rx invalid crypt:0  Rx invalid frag:0
      Tx excessive retries:0  Invalid misc:0   Missed beacon:0