Automatic Packet Reporting System


Bob Bruninga, WB4APR
wb4apr att amsat.org

Dayton Info: See the mobile and HT Setup notes for Dayton this year. Also be aware that you can use ANY HT with a DTMF keypad to report your position at Dayton. Tell your non-APRS friends and see Building Grid, Flea market East, Flea market West

Appalachian Trail Golden Packet Attempt: On the weekend of 25/26 July 09 we will try to get an RF packet the 2000 mile length of the AT. See details.

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. See the APRS Messaging/Contact Initiative. .

This page is in reverse chronological order. New information is at the top. For more background on APRS drill further down the page. For example, the map below from Hessu, OH7LZB's web site http://aprs.fi/ shows a one month snapshot of activity which reveals some gaps in the APRS coverage in the USA.


Click to see a year's animation!

There are many misconceptions about APRS? . See typical oversights and hear my talk on the 3 Oct 08 Rain Report
See also original APRSdos views and concepts which have been overlooked in some new programs.

Download: . . APRS-by-Bob Powerpoint (3 Mb) (Feb 09 version).

New Initiatives! . Over the last few years there have been several initiatives that have drastically improved APRS network performance and useability for users. The original APRS spec was updated in 2004 with the APRS1.1 addendum and APRS1.2 proposals. Most of these new initiatives are listed here.

  • APRS=>DTMF Paging Gateway Gates local APRS info to DTMF Paging radios
  • APRS RFID using RFID Name tags for locating individuals at a venue
  • CQ SERVER for sending global messages or CQ's using National GROUP Callsigns such as SCOUTS, SCR, IOTA, JOTA, etc.
  • Local Info Initiative to put locally useful info on the mobile APRS radio front panel
  • The New-N Paradigm is fixing the USA network. See Southern and Northern Europe progress. See New-N Statistics in Maryland.
  • APRS Touchtone (APRStt) shows how to use any DTMF HT to report in to APRS
  • Default Parser (Vicinity Tracking) to make sure every packet heard gets a posit. See also the original Commented Parser.
  • Tracker Manifesto Trackers are also 2-way participants in the network
  • AFRS Automatic Frequency Reporting System for rapid amateur radio emergency support or locally recommended Voice Frequency Objects.
  • APRS Email via the Amateur Satellites
  • Event and Field Data Entry using the D7 HT.
  • Voice Alert built-in simplex voice back-channel for APRS mobiles
  • State APRS WEB pages for each area of the country.
  • APRS Satellites . Operational: GO32, semi: PCSAT1, Echo, ISS2, decayed: PCSAT2, ANDE, RAFT, and in-work, P-sat.
  • Proportional Pathing for better local tracking and less QRM
  • SkyCommand uses UI Packets just like APRS and can be commanded from APRS HT's and mobiles.
  • APRS Special Event Ops for keypad data entry at special events.
  • Query the QRZ database from your HT or mobile!
  • Worldwide Digipeater maps by WA8LMF.
  • APRS-IS Core and Tier-2 servers web pages.
  • National Parks with APRS coverage.
  • MileMark database for position of non-APRS stations. Description, and Basic code, and mm-data.dat file.

    OVERVIEW: The Automatic Packet Reporting System was designed to support rapid, reliable exchange of information for local, tactical real-time information, events or nets. The concept, which dates back to the mid 1980's, is that all relevant information is transmitted immediately to everyone in the net and every station captures that information for consistent and standard display to all participants. Information was refreshed redundantly but at a decaying rate so that old information was updated less frequently than new info. Since the primary objective is consistent exchange of information between everyone, APRS established standard formats not only for the transmission of POSITION, STATUS, MESSAGES, and QUERIES, it also establishes guidelines for display so that users of different systems will still see the same consistent information displayed in a consistent manner (independent of the particular display or maping system in use). See the original APRS.TXT. The two images below should give you an idea of the kinds of information available to the mobile operator on his APRS radio. On the left is the Kenwood D710 radio showing the station list, and on the right is the attached GPS with map display showing the location of other APRS stations.

    Each station or object in the list has three more pages of information on it. The objects can show Repeater frequenceis in an area, meetings, nets, events, hamfests, echolink and IRLP nodes and frequencies, traffic speeds, accidents, emergency situations. And the attached GPS can show the location of each of these items.

    THE GOAL IS COMMUNICATIONS and LOCAL INFO UPDATE, -NOT- JUST VEHICLE TRACKING!

    APRS was never intended to be just a vehicle tracking system (GPS was added in the 1992 time frame when GPS became affordable). APRS is much more. See the Kenwood mobile display above. This is the STATION LIST which shows the nearest 100 stations heard. . In this case, not only are the two stations of AB9FX nearby, but also his current VOICE operating frequency is visible. Also, we can see that this radio is in OPERATING range of three voice repeaters that are also identifying themselves as objects on APRS as the locally recommended voice operating channels.

    APRS provides situational awareness to all operators of everything that is going on in his local area, whether it be Weather reporting, traveler info, Direction Finding, objects pointing to ECHOlink and IRLP, or Traffic reporting and emergency response. All of this while providing not only instantaneous operator-to-operator keyboard messaging capability for special events, but also an always-on Voice Alert backchannel between mobiles in simplex range. There is even an APRS interface to the WinLINK system called APRSlink, so that mobiles can send and receive Email without needing a PC. Think of APRS as a signalling channel to reveal ALL amateur radio resources and live activities that are in range of the operator at any instant in time.

    UBIQUITOUS OPERATIONS: Consistent with providing information on all resources within range, APRS must also work across all boundaries and in all areas of the continent for all travelers. For this reason, 144.39 MHz is dedicated to APRS throughout North America. Other continents have similar single frequencies such as 144.80 in Europe and 145.175 In Australia. Also after 14 years of evolution, APRS was greatly simplified beginning in the 2004 time frame to eliminate obsolete and inefficient routing. See the New-N Paradigm. Now, there is only one recommended PATH everywhere, and it is VIA WIDEn-N for fixed stations where N is usually 2 in most metropolitan areas and no more than 3 most everywhere else. Mobiles can use VIA WIDE1-1,WIDE2-1 in those 2 hop areas to gain help from nearby WIDE1-1 fill-in digipeaters. See the high density areas in the map below:


    See USA map of Mobiles
    See map of digis

    APRS GLOBAL INTERNET SYSTEM: Although APRS is a local, tactical real-time two-way communications system, the enormous free bandwidth of the Internet was added in the mid 1990's to allow global monitoring of all real-time data from all local communities around the world. Everything on any APRS frequency is being monitored locally and fed globally into the APRS internet system by hundreds of Igates See live list (complete) or a Map of I-G symbols. Not only does this allow for global monitoring of any local activity, it also allows two-way point-to-point messaging between any two APRS users anywhere on the planet (that has an APRS infrastructure). Think of it as everything goes in so it is available to everyone, but the only thing that comes from the internet back to local RF are messages and selected position data requested locally.

    UNIVERSAL TEXT MESSAGING FOR AMATEUR RADIO: . Recently, the local/global interconnectivity of APRS is being considered as a backbone to facilitate a Universal Text Messaging Initiative not only between any APRS users, but between any two radio amateurs completely independent of the type of device. They can use cell phones, blackberrys, pagers, DTMF HT's or just about any other kind of device. See the web page.

    APRS was developed by Bob Bruninga, WB4APR, as a real-time local tactical communications system for rapidly exchanging digital data of immediate value to operations. This really took off when GPS became available and MAPS were integrated into the system for tactical situational awareness of everything in the net. In the 13 years since its introduction, (see history) it has grown to encompass just about every aspect of Amateur Radio. For the original introduction to APRS, CLICK HERE or check out the first category of links below to get the big picture of what APRS is all about...

    The above shot was APRSdos in the early 1990's. Now it is world wide linked by K4HG's global FINDU.COM internet links. The map below shows the approximate 20,000 users now on the air in the USA. Or Click here to see the entire 30,000 worldwide users LIVE.

    (Refresh)

    Here are some other LIVE maps from around the country and the world showing the global, yet LIVE aspect of APRS:

    USA WEST:........ Southwest, Northwest, 4-Corners, Central CA, Southern CA, Hawaii
    USA CENTRAL: North Central, Midwest, South Centeral
    USA EAST:........ New England, Northeast, Mid Atlantic, Wash-DC, Southeast, Florida
    WORLD:............ Europe, S.America and Africa, Australia/NewZealand, Japan

    APRS-IS, the APRS Internet System: The APRS-IS is a worldwide network of internet gateways that provides end-to-end RF connectivity from any where on the globe within range of an IGate. In addition K4HG maintains FINDU.com which maintains a database of all packets heard anywhere at any time, up to the minute. For the live status of the APRS-IS, see this table.

    The remainder of this page is just a list of links to just about everything involving APRS in the last 10 years. To cover the breadth and depth of these applications, just follow the links...

    OVERALL APRS CONCEPT LINKS FOR NEW USERS:

    NEW ITEMS and IDEAS

    APRS SATELLITE PROJECTS

    OTHER APRS APPLICATIONS AND USES

    OTHER LIVE INTERNET APRS SITES

    OTHER APRS INFORMATION SITES

    APRS DATA and FILES

    HISTORICAL LINKS AND OLD STUFF

    Join the TAPR APRS Special Interest Group E-mail Reflector: APRSSIG


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