04.24.11
Decoding APRS packets with parts from your junk box
A few days ago I had a chance to talk to some amateur radio operators about something called Automatic Packet Reporting System (APRS). APRS is a low bandwidth data communications mechanism that operates in a manner similar to UDP multicast. Each packet is broadcast over the air, with no handshaking or acknowledgement. (Some automated systems will send an acknowledgement via a second transmission. As with UDP, this is the application’s responsibility.) A variety of information is available via APRS such as weather data, GPS position of vehicles, and text messages. While a great majority of APRS data in my area is available on the web, what’s the fun in that? I wanted to see if I could pull the data down over the air.
APRS is used to show all types of data: weather, car/truck/airplane telemetry, and text messages.