What is APRS?

In the words of its creator:

"APRS is not a vehicle tracking system. It is a two-way tactical real-time digital communications system between all assets in a network sharing information about everything going on in the local area. On ham radio, this means if something is happening now, or there is information that could be valuable to you, then it should show up on your APRS radio in your mobile. APRS also supports global callsign-to-callsign messaging, bulletins, objects email and Voice because every local area is seen by the Internet System (APRS-IS)! APRS should enable local and global amateur radio operator contact at anytime-anywhere and using any device."

-          Bob Bruninga, WB4APR (SK)

“APRS is not a vehicle tracking system.”

 

APRS can send many types of data, including, but not limited to:

 1.       Positions (usually transmitting station).

2.       Station capabilities.

3.       Objects (usually on behalf of other entity).

4.       Weather Reports from individual stations.

5.       Weather Alerts forwarded from the National Weather Service.

6.       Telemetry.

7.       “Messages” addressed to specific stations, with automatic retries and acknowledgment.

8.       Bulletins sent to wider groups.

9.       Queries and Responses.

10.   Ham Radio of Things.   (like Internet of Things but with Ham Radio)

11.   User Defined data types.

 

 APRS is designed for local communication over radio links, not global messaging through the internet. While the APRS-IS internet backbone is a useful addition, it's not essential.

Unlike centralized systems like mobile phones, APRS is a decentralized network with no central control. Stations communicate directly with each other or via digipeaters. No infrastructure is required.

Information in APRS comes directly from users (that means you!), not central servers. Users can receive and use information from nearby stations without needing an internet connection.

Digital Repeaters (digipeaters) retransmit packets to extend range.  You can buy an appliance or build your own using free computer software. The International Space Station (ISS) and some amateur radio satellites carry APRS digipeaters.

Internet Gateway (IGate) stations can move data between disjoint RF networks. aprs.fi is not an active participant in the APRS network. It simply acts as a viewer, collecting historical data and displaying it alongside other sources like maps.

 The core of APRS lies in lies in direct communication between stations or through digital repeaters called digipeaters. This decentralized system allows users to share information locally without relying on the internet.

Besides communicating with other people, there are many automated systems which will provide information as a result of your query.

Kenwood, Yaesu, and others recognize the importance of APRS, and build it into many of their radios. You can also participate with an ordinary transceiver and free software applications.

The key takeaway is that APRS is designed for local, radio-based communication, with the Internet playing a secondary role in data visualization tools like aprs.fi.