Personal Background
• KJ6VU
• Licensed in 1972
• Building repeaters since the ‘70s
• Cactus Intertie Nor Cal – Board of Directors
• Bay-Net – Board of Directors
• Builder / trustee of D-Star repeater WW6BAY
Content taken from various
presentations from…
John Hays K7VE
Debbie Fligor, N9DN
Dan Smith, KK7DS
… thanks !
Agenda
• Introduction to D-Star technology
– What is it?
– How does it work?
– What can you do with it?
• Building a D-Star & analog repeater system
• Summary
– Digital vs analog FM – pros and cons
– Using D-Star for emergency communications
What is D-Star ?
• Digital – Smart Technology for Amateur Radio
• ICOM’s implementation of JARL open standard for
UHF/VHF digital voice and data communications
• Equipment on 2 Meters, 440 MHz and 1.2 GHz
• Gaussian Minimum Shift Keying (GMSK) with forward
error correction
Why Should You Care ?
• Digital technologies applied to ham radio
• Spectrum efficiency
• Voice & data provides new options
• Audio quality does not degrade over multiple hops
• Eliminates noise on marginal signals
• World wide digital backbone
• Leverage the internet for backhaul
• It’s fun !
Fun Facts…
• > 16,000 registered D-Star users world wide
• > 680 internet gateways
• ~2,200 active users per day
Conventional wisdom
Proprietary Icom System
Crummy audio
Expensive radios
Very expensive repeaters
6 KHz bandwidth
D-Star First Impressions
Conventional wisdom
Proprietary Icom System
Crummy audio
Expensive radios
Very expensive repeaters
6 KHz bandwidth
My impression now
Open standard (mostly)
Pretty good audio
50% premium
New low cost alternatives
Not quite
Lots of new cool technology
New use models
Great user community
D-Star First Impressions
Conventional wisdom
Proprietary Icom System
Crummy audio
Expensive radios
Very expensive repeaters
6 KHz bandwidth
My impression now
Open standard (mostly)
Pretty good audio
30% premium
New low cost alternatives
Not quite
Lots of new cool technology
Enables new use models
Great user community
D-Star First Impressions
A Brief History of D-Star
JARL defines
D-Star spec
• Icom rolls out first D-Star products
• Early adopters install systems
• Call sign routing
• US usage starts to ramp up
• Popular with emcomm groups
• G1 and D-Plus gateways
• Many new technologies
DV dongle, GMSK Modem, DVAR, Reflectors
2001 2004 2006 2008 2011
• >16,000 users
• >600 repeaters
• DV Access Points
• Non-Icom repeaters
Growth of Non-Icom Equipment & Software
2001 2004 2006 2008 2011
DV Dongle DVAP
Radios
D-RATS
DVAR
Hot
Spot
StarGate
Repeater
Repeater Bands
K6ACS Santa Rosa 2m UHF
W6CO Mt. Veeder UHF
KS6HRP Folsom 2m
KD6SAC Citrus Heights 1.2
K6HDD Mt. Bullion 2m UHF 1.2
W6DHS Volcano 2m UHF 1.2
K6PIT Pittsburg 2m
K6MDD Mt. Diablo 2m UHF 1.2
W6YYY Oakland UHF
W6UUU Pleasanton UHF
K6LRG Mt. Alison UHF 1.2
WW6BAY Palo Alto UHF
KI6JUL San Jose 1.2
Available at www.bay-net.org
OUTPUT INPUT CALL LOCATION SPONSOR
144.9600 144.5600 W6DHS Volcano N6RDE
145.0400 144.6400 K6ACS Santa Rosa KD6RC
145.1300 144.5300 W6HHD Mariposa W6HHD
145.4500 144.8500 K6VIS Visalia TCARC
146.5800 147.5850 K6MDD Concord K6MDD
146.8950 146.2950 K6CHO Chico AREA 147.2400 147.8400 K6PIT Pittsburg K6PIT
147.6750 147.0750 KS6HRP Folsom SHARP
440.0375 445.0375 W6YYY Oakland N6LDJ
440.0500 445.0500 K6VIS Visalia TCARC
440.6000 445.6000 W6DHS Volcano N6RDE
442.1125 447.1125 K6ACS Santa Rosa K6ACS
443.8500 448.8500 WD6SJV Dunlap DCTS
444.0750 449.0750 WW6BAY Palo Alto BAY NET
444.1375 449.1375 K6MDD Concord K6MDD
444.6875 449.6875 K6LRG Fremont K6LRG
444.8000 449.8000 W6HHD Mariposa W6HHD
>24 DV Repeaters and >7 DD Nodes
In Northern California
OUTPUT INPUT CALL LOCATION SPONSOR 1284.1000 1272.1000 W6HHD Mariposa W6HHD 1284.2000 1272.2000 K6MDD Concord K6MDD 1284.5000 1272.5000 KD6SAC Folsom K6HLE 1285.3000 1273.3000 WD6SJV Dunlap DCTS 1286.3250 1274.3250 K6VIS Visalia TCARC 1286.5250 1274.5250 K6CHO Chico AREA 1286.5250 1274.5250 KI6JUL San Jose AREA 1286.6250 1274.6250 K6LRG Fremont K6LRG
1249.0750 1249.0750 K6MDD Concord K6MDD1249.2250 1249.2250 W6HHD Mariposa W6HHD1250.0000 1250.0000 WD6SJV Dunlap DCTS1255.0000 1255.0000 K6VIS Visalia TCARC1299.3500 1299.3500 K6CHO Chico AREA1299.3500 1249.3500 KI6JUL San Jose AREA1299.5000 1299.5000 KD6SAC Folsom K6HLE
Digital Voice
Digital Voice
Digital Voice
Digital Data
User Registrationhttps://dstargateway.dcara.net/Dstar.do
• You can listen but not
access a repeater
until you register
• Centralized
registration system
• Free
• Allows you to use any
D-Star repeater
Using D-Star Simplex
WW6BAY G
TALKING TO K1XYZ
K1XYZ
VK8RAD G
Boston, MA
San Jose
W6ABC = MyCall
UrCall =
RPT2 =
CQCQCQ
WW6BAY BRPT1 =
K6DEF
UR = CQCQCQ
RPT1=
RPT2=
MY = W6ABC
Using D-Star for On a Local Repeater
WW6BAY G
TALKING TO K1XYZ
K1XYZ
VK8RAD G
Boston, MA
San Jose
W6ABC = MyCall
UrCall =
RPT2 =
CQCQCQ
WW6BAY BRPT1 =
K6DEF
UR = CQCQCQ
RPT1= WW6BAY B
RPT2=
MY = W6ABC
Using D-Star
Repeater to Repeater Linking
WW6BAY B
WW6BAY G
TALKING TO K1XYZ
K1XYZ
VK8RAD G
Boston, MA
San Jose
W6ABC = MyCall
UrCall =
RPT1 =
RPT2 =
CQCQCQ
UR = CQCQCQ
RPT1= WW6BAY B
RPT2= WW6BAY G
MY = W6ABC
Using D-Star Reflectors
WW6BAY B
WW6BAY G
TALKING TO K1XYZ
K1XYZ
Boston, MA
San Jose
W6ABC = MyCall
UrCall =
RPT1 =
RPT2 =
CQCQCQ
Reflector
Gateway
Gateway
UR = REF014CL
RPT1= WW6BAY B
RPT2= WW6BAY G
MY = W6ABC
Cool Stuff…
D-VAP – Digital Voice Access Point
• 1 mw 2m simplex data radio
• USB connection to the PC
• Provides portable RF access
to the D-Star network
• All you need is an internet
connection
• Take the network with you
Cool Stuff…
DV Dongle
• Turns your computer into
a D-Star “radio”
• Built in DVSI CODEC
• Simple PC program
controls the dongle
• Windows, MAC, Linux
The Cost of D-Star
$530$290
$479$329
Conventional Conventional & D-Star
the cost of
1-2 CW Filters
D-Star is…
Data Rates & Bandwidth For DV Mode
(What you use on 2m & UHF)
2400 bps AMBE encoded voice
1200 bps Forward Error Correction (FEC) for voice
1200 bps data (text messages, GPS, etc…)
4800 b
ps
“Slow speed data mode”
DVSI = Digital Voice Systems Inc
“World leader in low-bit-rate speech compression technology”
Designer of the AMBE CODEC algorithm and chips
Used on satellite phones and land mobile applications
Anyone can buy the chips for about $20
DVSI AMBE 2020 CODEC chip
DVSI AMBE 2020 CODEC chip
Digital Voice Data Format – Header Section
CQCQCQ WW6BAY B WW6BAY G W6ABC BOB
D-Star Bandwidth
Better Than Traditional Narrow Band FM
40 db down @ 6 Khz away 20 db down @ 6 Khz away
D-Star uses GMSK modulation
Gaussian Minimum Shift Keying
• D-RATS
• DStarlet
• d*Chat
• Dstarusers.org
• D-PRS interface/javAPRSSrvr
• uSmartDigi D-Gate D-STAR Gateway D-STAR/APRS
Interface
• D-STAR query
• Opendstar.org Applications
Other D-Star Applications
D-RATS
Slow speed digital mode application
• All-in-one tool for D-STAR data
• Real uses for the data channel
• Oriented at EmComm applications
• No dependence on infrastructure
• Works on simplex
• Works on a gateway network
Features• Email
• ICS & Radiogram forms
• Messaging
• Chat
• File transfer
• Position reporting
Runs on…• Windows
• MAC OS
• Linux
Agenda
• Introduction to D-Star technology
– What is it?
– How does it work?
– What can you do with it?
• Building a D-Star & analog repeater system
• Summary
– Digital vs analog FM – pros and cons
– Using D-Star for emergency communications
Intro to Bay-Net
• History
– 1999 ARC State Lead Unit & Cactus sign Statement of Understanding
– 2005 Bay-Net created by NCCRA - First NCCRA “open repeater” system
– 2006 Started working with ARCBA and Orinda ARES
• Goal
– Open repeater system covering the bay area
– Supporting public service organizations including
American Red Cross Bay Area chapters
Orinda ARES
• Financial and technical support by
– System owners
– Northern Cal Cactus Radio Association
– Sierra Radio Systems Bay-Net
San Bruno Fire
6:20 Burlingame Red Cross comm team
alerted to check in to Bay-Net
6:25 Emergency net activation
Cell phone system was unreliable
– Network overload
- Equipment failure at fire site
Bay-Net was the main communications link
between…
• Burlingame Red Cross
• San Bruno EOC
• ICP
• Evacuation Center
Nets running for more than one week
Bay-Net
145.390
Repeater
443.225
Repeater
927.8625
Repeater
IRLP / EchoLink
ComputerLink
Radio
145.390
Repeater
Control System
443.975
Repeater
Link
Radio
Control System
Link
Radio
Black Mountain East Bay Hills
Internet
444.075
Repeater
Computer
Modem
Internet
444.350 Duplexer
444.075 Duplexer
GaAs FET Preamp
& Cavities
444.350 Repeater
444.075 Repeater
Cactus 420 Link Radio
Control System
Site Controller
D-Star Computer
Site Controller Computer
WW6BAY D-STAR Block Diagram
Celwave 526 Duplexer
Angle Linear GaAs FET
preamp and filter
Maxtrac Rx Maxtrac Tx
Satoshi modem board
Intel ATOM mobo
Centos 5.4
G4ULF NI-Star SW
USB
InternetEthernet
Agenda
• Introduction to D-Star technology
– What is it?
– How does it work?
– What can you do with it?
• Building a D-Star & analog repeater system
• Summary
– Digital vs analog FM – pros and cons
– Using D-Star for emergency communications
Digital vs Analog
Analog
Digital
Solid copy
Solid copy
Increasingly noisy
“R2D2”
No
Signal
No
Signal
Not intelligible
Many claim one has better range than the other
Too close to tell
However, D-STAR hangs in longer without noise
Both Have Downsides…
Analog
– Gets noisy
– Squelch tails
D-Star
– Disruption in the header (first 600 bits)
will cause the whole transmission to fail
– More complicated setup and operation
D-Star for Emergency Communications
For voice comms - conventional FM is generally better
– Universally interoperable
– Easy to use
– Cheap
How can D-Star be used?
– D-Star can be ideal if you have internet access
using a D-VAP
– Excellent secondary support system
– Use data channel for position and messaging
– Callsign routing can be very handy
– Wide area / out of area comms