Horst is an application to monitor wireless traffic. It gives you statistics about the wireless medium, and have a nice curses UI for a human to read.
Normally, you use horst to visually monitor the network traffic. To use horst, you first have to put the wireless interface into monitor mode, see this page for more information on how to put the driver into monitor mode. When you have put the wireless interface into monitor mode, use this command to start horst:
# horst -i wlan0
assuming you have named the monitor wlan0.
There are several customizations you can do to configure horst the way you like it, for a short help type:
# horst -h
- horst homepage http://br1.einfach.org/tech/horst/