ADS-B (Automatic Dependant Surveillance – Broadcast) is a system for tracking aircraft that relies on individual aircraft “squittering” their position and other data automatically every second or so on the SSR response (Secondary Surveillance Radar) frequency of 1090Mhz.

There are now low cost receivers available as a USB Dongle that are based on Software Defined Radio (SDR) technology. Jeff VE3EFF has set up a receiver at the STP site that is continually “listening“ and dumping data. Clink on the link to see aircraft in the area.