Transcript APRS in Wisconsin

APRS
The Automated Packet
Reporting System
by: Andy Zwirko - K1RA
[email protected]
http://www.k1ra.us/
Presentation Overview
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Definition, purpose and scope of APRS
APRS Pitfalls & Misconceptions
History of APRS and its inventor
Station Hardware
Network and data flow
APRS protocol and raw packet decodes
Software
FARA members on APRS
The future of APRS and opportunities
Links
What is APRS?
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APRS = Automatic Packet
Reporting System
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APRS is an open system that
uses unconnected AX.25
radio packets to transmit and
collect data.
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APRS data is usually overlaid
on a map
APRS is:
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A two-way information exchange using radio
A one-to-many, unconnected packet protocol.
A tactical protocol designed for local RF use.
A protocol with many reporting capabilities.
A protocol with SMS capabilities.
A protocol also adapted to the Internet.
A protocol with extensive flexibility built-in.
A protocol still under development.
Purposes of APRS
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Immediate digital information exchange
between all participants in a local area or
event. This includes:
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Positions and status of all stations and objects (GPS)
Messages, Bulletins and Announcements
Assist in Search and Rescue operations
Gather and track weather data and telemetry (satellite,
remote)
DF bearings and signal strengths for quick transmitter
hunting
RF Connectivity plots of all stations
Local OBJECTS on a common map display for all
users
Local Freqs, Nets, Meetings, Marathons, Races, Events
Field Data
APRS Network Nodes
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Home stations
Mobile and Portable GPS tracker stations
Automatic Weather Stations
Digipeaters
Internet I-Gates
Scope of APRS
APRS Pitfalls & Misconceptions
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That APRS is just Vehicle Tracking vs. a Real-Time Information Distribution System.
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That APRS is dependent on GPS for its value (GPS is not needed. See Objects).
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Failure to use the APRS built-in Mile-Marks for tracking all other non-APRS mobiles.
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Using APRS clients that only do maps and ignore many of the APRS fundamentals.
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Failure to understand the importance of Objects
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Not understanding the APRS operator’s role as a Data Input (Objects, Messages, etc)
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Failure to use real-time messaging:
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Not using the D7 and D700 as data entry and clipboard display units at field events.
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Too much focus on Large Screen Displays vs. Individual Operator displays for events.
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Failure to display APRS symbols with all their attributes and colors
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Failure to manage the network by adjusting a local digipeater for the situation at hand.
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Not realizing the importance of Voice Operating frequencies in APRS.
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Failure to implement the original APRS Centralized Common Bulletin Board concept.
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Ignore the fundamental Decay Algorithm to accelerate new data, and decay old data!
Founder & History
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Bob Bruninga, WB4APR is
considered the “Father of APRS”
and is still active on a daily basis.
Bob is a member of the United
States Naval Academy Aerospace
Engineering Dept.
APRS was developed in the early
1990's for local tactical digital
communications, situational
awareness and TWO-WAY
information exchange using
Amateur radio.
Bob Bruninga first used to track
horses in 1994
Designed to “be a cost effective
mapping program that would allow
positioning of mobile stations
using GPS receivers.”
What is needed to participate?
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Operating via RF
Radio - VHF transceiver and antenna
 TNC - Terminal Node Controller
 Computer with APRS software installed
 GPS (optional) for mobile stations
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Operating via the Internet
Computer with browser or APRS software
 Mobile phone with browser or APRS software
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VHF Transceiver
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Any 2 meter radio will work as long as it will
work on 144.390 carrier squelch
You will need to make a cable to connect mic
audio, RX audio, and PTT to the TNC
TNC Encode/Decode
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Known as a radio modem, converts the digital
information from the computer and/or GPS
into audio tones and AX.25
The APRS network runs at 1200 baud
TNC Encode (only)
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Cheaper than a regular TNC ($30-45) but it only
transmits data
Has a single port that only allows connection to
a GPS
Tiny Trak 3
Open Tracker 1+
APRS Enabled Radios
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Some radios have built in TNCs for direct
connection to a computer or APRS interaction
right on the display.
Alinco DR-135
Kenwood TH-D7A
Kenwood D-700A
GPS Receivers
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Uses military controlled GPS
satellites available to general
public
Typical positions accuracy
ranges from 1-5 feet
GPS must output NMEA to
work with APRS
Many models available for
under $100
Serial, USB, Bluetooth
interfaces available to PC
Station Configurations
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Dedicated APRS system
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GPS
Computer
Radio (separate)
TNC (encode/decode)
Mic-E APRS system
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Radio (shared)
TNC (encode only)
GPS
Dedicated Equipment Pros / Cons
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Pros
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Can watch other units on map and send messages
Position is sent out at predetermined intervals
Separate radio system in car in case your 2M voice radio dies
Separate radio infrastructure in case your repeater goes down
Could also be used as Winlink or Packet station
Cons
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Another radio in the car
More 2M RF to interfere with your local repeater traffic
Higher cost because of more equipment
Mic-E Pros and Cons
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Pros
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Don’t have to install another radio in the car
Cheaper than the dedicated equipment way
Can use the cheaper encode only TNC
Cons
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Can not track other units on a map
Can not send messages to other units
Position only goes out when you talk on the radio
Position on map could be very old since you didn’t talk on radio
More expensive for the repeater owners
Won’t work on all repeater systems
No back-up radio if your voice radio fails
If the repeater fails, no one sees your position
Home / Fixed System
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APRS Home Station without a GPS
TNC
Computer
Radio
Trackers (one-way)
One-way APRS is not normally recommended. APRS is a Network. We
want good communications among all participants for maximum utility.
Trackers have no
APRS data display.
So the receiver
should be tuned to a
beaconed Voice
frequency so the
operator can be
involved in the Net!
One-way trackers are good for non-manned assets at large
movement events.. Not as the only APRS asset for a ham.
Tracker System
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Portable tracker box, with no compute or display
GPS
2m Antenna
Tracker
Radio
APRS Network Nodes
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Stations
Home
 Mobile
 Digipeaters
 Satellites
 I-Gates
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APRS is a Network intended for real-time, two-way
tactical information exchange.
SSID Suggestions
Special Station Identifier (SSID) allows multiple stations with the same callsign to coexist on
the network
No SSID - Home Station, Home Station running I-Gate
-1 Digipeater, Home Station running a Wide1-1 Digi, WX Digipeater
-2 Digipeater [#2 or] on 70CM
-3 Digipeater [#3]
-4 HF to VHF Gateway
-5 I-Gate (Not home station)
-6 is for Operations via Satellite
-7 Kenwood D7 HH
-8 is for boats, sailboats and ships (maybe 802.11 in the future)
-9 is for Mobiles
-10 is for operation via the internet only
-11 is for APRS touch-tone users (and the occasional Balloons)
-12 Portable Units such as Laptops, Camp Sites etc.
-14 is for Truckers
-15 is for HF
Digipeaters
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Extend the coverage of the
portable and mobile units
Much like a repeater but
operating on a simplex
frequency.
Usually located at a high
location on a tower
Can also be located at
someone’s home to help fill in a
certain area.
Paths WIDEn-N vs. Named
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Digipeaters acknowledge WIDEn-N paths
WIDEn-N paths are decremented for each hop
Never need more than WIDE2-2
Named path most efficient form of message
propagation
Only the station with the matching Alias will digipeat
the message
WD4HDL-1, N3HF-1
I-Gates – Tier2 Global Net
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I-Gates are internet gateways that expand the reach
of APRS worldwide – www.aprs2.net
An I-Gate listens to the local RF channel and relays
the information into an APRS Internet data stream.
I-Gates also relay information from the Internet
data stream to a local RF station
Benefits of I-Gates
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Reduces RF network congestion
Increases the trackability of mobile stations
Allows RF access of weather service bulletins
and alerts
Can set up an APRS station without a radio and
TNC
Any APRS station can be queried at
www.findu.com or www.aprs.fi
Typical Local APRS Network
Internet
Gateway
Digipeater
Home
Fixed
Mobiles
Digipeater
Portables
APRS Data Flow
APRS Protocol
APRS Data Types
APRS Position Protocol
APRS Object Protocol
APRS Message Protocols
APRS Map Symbols
Raw APRS Packets
Decoded APRS Packets
• Location and Status
Decoded APRS Packets
• Location and weather report
APRS Software
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PC Clients
APRSDos
 WinAPRS/MacAPRS
 UI-View
 APRSpoint
 APRS+SA
 Xastir (Linux / Unix)
 Internet Browser
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PDA Clients
AprsCE
 APRS-Go
 APRS-Palm
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I-Gate
JavAPRS
 AHub
 aprsD
 NOSaprs
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APRSDos
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The original APRS application. Development
going back to 1992
Very rudimentary maps
Has satellite tracking features, network
utilization analysis, and direction finding support
Price – free
http://www.usna.edu/Users/aero/bruninga/apr
s.html
APRSDos
WinAPRS
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Uses USGS Tiger maps and integrates with
Precision Maps from Undertow Software
Also uses old style APRSDOS vector maps.
NWS weather data overlay capability
Price – free
http://www.winaprs.com
Also hosts X-APRS, MacAPRS, dosAPRS
WinAPRS
UI-View
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Lots of features, more complex interface
Handles plug-ins (ex: NWS radar, Sat. telemetry)
Vibrant developer network
Uses user generated, or raster maps.
Integrates with Precision maps. Plug-ins for
Street Atlas, Mapblast and Tiger Maps
Price – free
http://www.uiview.org
UI-View
UI-View
APRSpoint
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Easy to use, familiar Microsoft style interface
Requires MapPoint 2004, 2006, 2009 or 2010
Provides for routing
Price – $77 with maps, $47 without maps
http://www.aprspoint.com
APRSpoint
APRS+SA
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Interfaces with Delorme Street Atlas USA
Offers text-to-speech capabilities
Price - free
APRS-Go
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Windows
Mobile / PDA
Uses OSM
public map set
Works with
many TNCs
Price – free
PC version too
http://www.aprsgo.com/
Online APRS Resources
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While APRS is
intended to be a
primary network that
does not require the
Internet, many users
use online national
databases to track
stations
APRS Real Time Propagation
http://www.mountainlake.k12.mn.us/ham/aprs
www.APRS.fi - Mapping
www.APRS.fi - Weather
www.APRS.fi - Beacons
www.findU.com - Mapping
www.findU.com – Nearby-In Range
Google for “USNA Buoy” Select USNA-1
www.findU.com - Messages
FARA on APRS
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KX4O – John – Mobile Tracker & Golden Packet
W4IFI – Randy – Mobile Tracker & Wx
KD6AKC – Mark – Mobile Tracker
N4YXW – Chuck – Internet Gateway
KW4VA – Andy (K1RA) – Echolink gateway
APRS Golden Packet 2010
APRS Golden Packet 2010
APRS Golden Packet 2010
Future of APRS
International Space
Station (ISS)
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The ISS was equiped
with an APRS receiver
on 145.825 recently
Used for crew to send
messages to friends,
family, and amateur
radio operators
Designed to track ISS in
space
Used as a space
digipeater in the APRS
space satellite
constellation
More info at
www.ariss.net
APRS Satellite Tracking & Reporting
System
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ASTARS - http://www.aprs.org/astars.html
APRS Opportunities
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APRStt (APRS touchtone decoding)
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Simple DTMF memory
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One button reports Position, Freq. and Status
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On every voice repeater
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On every IRLP node
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On every Echolink node
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Any where on .52!!
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ONLY NEEDS local software upgrade
AVRS (Automatic Voice Relay System) Global VOIP via APRS
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Uses APRS message to set up call
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Automatically links to Echolink or IRLP
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Radio auto-QSY’s to make link (Ham Radio Cell phone from Mobile)
APRStt (Touchtone)
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Simple DTMF memory - One button puts you in APRS (Position, Frequency and Status)!
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DTMF on voice freq translated to packet on APRS channel (or direct to APRS-IS)
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Position is 10 mile ambiguity using repeater posit (or 60 mile ambiguity out west)
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Frequency in packet is Frequency of Repeater
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If Echolink or IRLP, APRS packet includes node number!
APRStt (Touchtone)
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For WB4APR, the DTMF Sends:
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This is converted to an APRS packet on the APRS channel as:
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#A922444427A77D
WB4APR-11>APRStt,WIDE1-1:!DDM_.__N/DDDM_.__W$146.895MHz T107 IRLP7070
Puts you on global map near Baltimore Maryland, with your
immediate calling frequency, your Tone and your IRLP node number.
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That is everything you need to be known to the Global APRS system!
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We have had this since 2001 (in DOS w DTMF chip).
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We need someone to do this with a sound card in windows?
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Build into every Echolink/IRLP node and every Repeater controller
with a serial port!
Unless we get APRStt and therefore 100% situational awareness of any
Ham mobile or HT then APRS will always be a side show only used by 10%
of any club or organization.
How about: #B95*234*2D => Milemark #234 on Route 95, northbound
APRStt (Touchtone)
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DTMF Report shows on APRS
147.105MHz T107 R30m
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CALLSIGN with date and time
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Position in vicinity of repeater or APRStt entry point
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Voice Operating Frequency, Tone and other info
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Node number if Echolink or IRLP, or reverse patch number if Repeater
APRStt (Touchtone)
As simple as adding
a DTMF chip to a
Micro-Trak
Or adding a DTMF
chip to an OT and
HT for use in the
field at a special
event
APRStt, maps and events
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That APRS is dependent on GPS for its value
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(GPS is not required to put things on maps).
APRS Voice Alert!
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Voice Alert is effectively 3rd Radio
channel for the D7 and D700 APRS
radios
Set the APRS Band A to PL-100
and keep the volume turned up:
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You wont hear any packets on 144.39 *
But you will hear a voice call using PL-100 on 144.39
And you will hear* an occasional Ping packet if
another D700 comes in line-of-site to you, like a
proximity radar alerting you to local presence.
Great for long haul traveling and meeting other
APRS users.
Links
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WB4APR – APRS Home - http://www.aprs.org/
APRS Protocol –
ftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdf
ftp://www.tapr.org/aprssig/aprsspec/spec/aprs101m/
APRS Info Wiki – http://info.aprs.net/
APRSSIG Users Group – http://tapr.org/mailman/listinfo/aprssig
APRS Apps - http://www.eskimo.com/~archer/aprs_capabilities.html
APRS-IS – Internet Spec Info - http://www.aprs-is.net/
APRS Tier2 Network – http://www.aprs2.net
APRS.fi Map & Database – http://www.aprs.fi/
OpenAPRS Map – http://www.openaprs.net/
FindU APRS Map & Database – http://www.findu.com/
APRS & Edge of Space Science – http://www.eoss.org/aprs
APRS on ISS – http://www.usna.edu/Users/aero/bruninga/iss-faq.html
APRS Balloons – http://www.aprs.org/balloon-n8pk.html
PCSAT2 – http://www.usna.edu/Users/aero/bruninga/pcsat2.html
Meteor Scatter – http://www.usna.edu/Users/aero/bruninga/meteors.html