D-Star

1
D-Star

• An Introduction to the JARL standard for Digital
  Voice and Digital Data on VHF/UHF/Above

2
What is D-STAR

• Digital Smart Technologies for Amateur Radio
• 1999 Funded by the Japanese Government and
  administered by the Japanese Amateur Radio League
  (JARL)
• 2001 Open Specification Published anyone can
  implement http//www.arrl.org/FandES/field/regula
  tions/techchar/D-STAR.pdf
• Current Implementations
• Digital Voice (with simultaneous low rate data)
  on 2 meters
• Digital Voice (with simultaneous low rate data)
  on 70 centimeters
• Digital Voice (with simultaneous low rate data)
  on 23 centimeters
• Digital Data (128Kbps) on 23 centimeters
• Backbone (10 Mbps) on 10 gHz. band
• Internet Gateways

3
Terminology

• Digital Voice (DV)
• 4800 bps data stream real time encoded with
• 2400 bps voice (AMBE encoded)
• 1200 bps Forward Error Correction (FEC) for voice
• 1200 bps data (text messages, GPS, telemetry,
  etc.)
• 6.25 kHz. Bandwidth using GMSK
• Digital Data (DD)
• 128 kbps data stream
• 150 kHz. Bandwidth
• Possible extensions to other rates and bandwidths
• E.g. 4800 bps in 6.25 kHz. (not current standard)
  on repeaters

4
Terminology

• Backbone
• 10 mbps data rate
• 10.5 mHz. bandwidth
• Point-to-Point
• Alternatively 2.4 and 5.8 gHz.
• using stock or modified Part 15 devices
  (WiFi/WiMax)
• Not D-STAR Standard
• Gateway
• Internet linking of D-Star Repeaters and Access
  Points

5
Terminology

• AMBE
• Advanced Multi-Band Excitation (AMBE) is a very
  powerful proprietary speech coding standard
  developed by Digital Voice Systems, Inc. (From
  http//en.wikipedia.org/wiki/Advanced_Multi-Band_E
  xcitation)
• Converts audio to and from the digital format
  used in D-Star Digital Voice at 2400 bps with
  1200 bps of FEC.
• FEC
• Forward Error Correction

6
The DV Protocol
Data
Radio Header
7
The DV Protocol
Alternating Audio/Data
8
The DD Protocol
9
The DD Protocol
TCP/IP
10
How Does DV Sound?

• Strong Mobile D-Star Signal
• Weak Mobile D-Star Signal
• Weak D-Star vs. Weak FM
• D-Star DTMF Sample

Sound samples courtesy KC5ZRQ
11
Making a Contact Simplex

• General Call
• Your Call CQCQCQ
• RPT1
• RPT2
• My Call K7VE
• Specific Station
• Your Call KZ7ZZZ
• RPT1
• RPT2
• My Call K7VE
• Call Groups
• 100 groups (00-99)

• General Call
• Calling CQ
• Roundtables/Nets
• Most Common
• Specific Station
• When other station is using callsign squelch
• Send Message
• Emergency Override

12
Making a Contact Local Repeater

• General Call
• Your Call CQCQCQ
• RPT1 WA7GIE C
• RPT2
• My Call K7VE
• Specific Station
• Your Call KZ7ZZZ
• RPT1 WA7GIE C
• RPT2
• My Call K7VE
• Call Groups
• 100 groups (00-99)

• General Call
• Calling CQ
• Roundtables/Nets
• Most Common
• Specific Station
• When other station is using callsign squelch
• Send Message
• Emergency Override

13
Making a Contact Zone Repeater

• General Call
• Your Call CQCQCQ
• RPT1 WA7GIE C
• RPT2 WA7GIE B
• My Call K7VE
• Specific Station
• Your Call KZ7ZZZ
• RPT1 WA7GIE C
• RPT2 WA7GIE B
• My Call K7VE
• Call Groups
• 100 groups (00-99)

• General Call
• Calling CQ
• Roundtables/Nets
• Most Common
• Specific Station
• When other station is using callsign squelch
• Send Message
• Emergency Override

14
Zone Repeater Illustration
WA7GIE C
WA7GIE B
Controller
70 CM UR CQCQCQ RPT1 WA7GIE B RPT2 WA7GIE
C MY K7VE
2 M UR CQCQCQ RPT1 WA7GIE C RPT2 WA7GIE B MY
KC7PAA
15
Zone Repeater Illustration
WA7GIE C
WA7GIE B
Controller
70 CM UR KC7PAA RPT1 WA7GIE B RPT2 WA7GIE
C MY K7VE
2 M UR K7VE RPT1 WA7GIE C RPT2 WA7GIE B MY
KC7PAA
16
Making a Contact Gateway

• General Call
• Your Call /K5TIT
• RPT1 WA7GIE C
• RPT2 WA7GIE G
• My Call K7VE
• Specific Station
• Your Call KZ7ZZZ
• RPT1 WA7GIE C
• RPT2 WA7GIE G
• My Call K7VE

• General Call Through Gateway
• Calling CQ
• Most like IRLP
• Be sure to give reverse routing
• Specific Station Through Gateway
• Calling specific Station
• Dont need to know other stations location
  (City, Repeater, Freq., )
• When other station is using callsign squelch
• Send Message

17
Gateway Illustration
WA7GIE B
K5TIT B
WA7GIE C
K5TIT A
Controller
Controller
Repeaters and Gateways should have club call
signs
Internet or Backbone
GPS
23 CM UR K7VE RPT1 K5TIT A RPT2 K5TIT G MY
N5MIJ
70 CM UR N5MIJ RPT1 WA7GIE B RPT2 WA7GIE G MY
K7VE
18
Applications

• DD About anything you could do on the Internet
  (WWW, FTP, Telnet, )
• Text Messaging
• D-GPS
• Future VOIP Telephone Interconnect (Uberpatch
  assign your radio a public telephone number.)
• Whatever you can imagine

19
Cost Comparison

• FM AX.25 1200 Baud
• Single Band Handheld 119 (Icom V82)
• TNC 189.95
• Interconnecting Cables 9-39

• D-Star
• Single Band Handheld 119 (Icom V82)
• UT-118 199.95

Essentially the same price!!! Use IC-2200H
(139.00) for mobile comparison.
20
Homebrew?

• Software Watch http//opendstar.org
• Hardware http//www.moetronix.com/dstar/

21
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22
Websites

• http//www.dstarusers.org
• http//groups.google.com/utah-d-star-users
• http//www.icomamerica.com
• http//www.icomamerica.com/support/forums/
• http//groups.yahoo.com/group/illinoisdigitalham
• http//groups.yahoo.com/group/dstar_digital
• http//k7ve.ampr.org
• And many more

23
Questions?

• Can I use D-Star through an FM Repeater?
• Does it work through a Satellite?
• Can I link a traditional FM repeater, IRLP,
  Echolink, to D-Star?
• Is anybody using this?
• Are we only going to get radios from Icom?
• Is it really an open system? How can that be with
  a proprietary chip like the AMBE 2020?
• Others?