Ubuntu - WiFi - Scan for WiFi connections

NOTE: iwlist is the old command, there's the newer iw command. 

iw scan
 
iwlist scan

or 

iw wlan0 scan | egrep 'SSID|signal'
 
sudo iwlist wlan0 scanning | egrep 'Cell |Encryption|Quality|Last beacon|ESSID'

Help

See: 

man iwlist