Automatic Packet Reporting System

In addition, all such data are typically ingested into the APRS Internet System (APRS-IS) via an Internet-connected receiver (IGate) and distributed globally for ubiquitous and immediate access.

APRS was developed from the late 1980s forward by Bob Bruninga, call sign WB4APR, a senior research engineer at the United States Naval Academy.

Bob Bruninga, a senior research engineer at the United States Naval Academy, implemented the earliest ancestor of APRS on an Apple II computer in 1982.

The first use of APRS was in 1984, when Bruninga developed a more advanced version on a VIC-20 for reporting the position and status of horses in a 100-mile (160 km) endurance run.

Following a series of Federal Emergency Management Agency (FEMA) exercises using CETS, the system was ported to the IBM Personal Computer.

During the early 1990s, CETS (then known as the Automatic Position Reporting System) continued to evolve into its current form.

APRS contains a number of packet types, including position/object/item, status, messages, queries, weather reports and telemetry.

Moving stations (portable or mobile) automatically derive their position information from a GPS receiver connected to the APRS equipment.

[8] The map display uses these fields to plot communication range of all participants and facilitate the ability to contact users during both routine and emergency situations.

In addition to real-time position reporting capabilities using attached GPS receivers, APRS is also capable of transmitting a wide variety of data, including weather reports, short text messages, radio direction finding bearings, telemetry data, short e-mail messages (send only) and storm forecasts.

While the map plotting is the most visible feature of APRS, the text messaging capabilities and local information distribution capabilities, combined with the robust network, should not be overlooked; the New Jersey Office of Emergency Management has an extensive network of APRS stations to allow text messaging between all of the county Emergency Operating Centers in the event of the failure of conventional communications.

In its most widely used form, APRS is transported over the AX.25 protocol using 1,200-bit/s Bell 202 AFSK on frequencies located within the 2-meter amateur band.

Stations can tap into this stream directly, and a number of databases connected to the APRS-IS allow Web-based access to the data as well as more advanced data-mining capabilities.

A number of low-Earth orbiting satellites, including the International Space Station, are capable of relaying APRS data.

An APRS infrastructure comprises a variety of Terminal Node Controller (TNC) equipment put in place by individual amateur radio operators.

In APRS, generic call signs are assigned to repeater stations to allow a more automatic operation.

Aircraft and balloon APRS stations should avoid beaconing with any path at altitude since digipeating may not be necessary due to their antenna height and likelihood of reaching multiple wide-ranging digipeaters and IGates.

These smaller trackers have used Morse code, Field Hell, and RTTY to transmit their locations and other data.

[17] The APRS protocol has been adapted and extended to support projects not directly related to its original purpose.