
D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol specification for
amateur radio
Amateur radio, also known as ham radio, is the use of the radio frequency radio spectrum, spectrum for purposes of non-commercial exchange of messages, wireless experimentation, self-training, private recreation, radiosport, contesting, and emer ...
. The system was developed in the late 1990s by the
Japan Amateur Radio League and uses
minimum-shift keying
In digital modulation, minimum-shift keying (MSK) is a type of continuous-phase frequency-shift keying that was developed in the late 1950s by Collins Radio employees Melvin L. Doelz and Earl T. Heald. Similar to OQPSK, MSK is encoded with bit ...
in its
packet-based standard. There are other digital modes that have been adapted for use by amateurs, but D-STAR was the first that was designed specifically for amateur radio.
Several advantages of using digital voice modes are that it uses less
bandwidth
Bandwidth commonly refers to:
* Bandwidth (signal processing) or ''analog bandwidth'', ''frequency bandwidth'', or ''radio bandwidth'', a measure of the width of a frequency range
* Bandwidth (computing), the rate of data transfer, bit rate or thr ...
than older analog voice modes such as
amplitude modulation
Amplitude modulation (AM) is a signal modulation technique used in electronic communication, most commonly for transmitting messages with a radio wave. In amplitude modulation, the instantaneous amplitude of the wave is varied in proportion t ...
and
frequency modulation
Frequency modulation (FM) is a signal modulation technique used in electronic communication, originally for transmitting messages with a radio wave. In frequency modulation a carrier wave is varied in its instantaneous frequency in proporti ...
. The quality of the data received is also better than an analog signal at the same
signal strength
In telecommunications, particularly in radio frequency engineering, signal strength is the transmitter power output as received by a reference antenna at a distance from the transmitting antenna. High-powered transmissions, such as those used i ...
, as long as the signal is above a minimum threshold and as long as there is no
multipath propagation
In radio communication, multipath is the propagation phenomenon that results in radio signals reaching the receiving antenna by two or more paths. Causes of multipath include atmospheric ducting, ionospheric reflection and refraction, and ...
.
D-STAR compatible radios are available for
HF,
VHF,
UHF
Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter ...
, and microwave amateur radio bands. In addition to the over-the-air protocol, D-STAR also provides specifications for network connectivity, enabling D-STAR radios to be connected to the Internet or other networks, allowing streams of voice or packet data to be routed via amateur radio.
D-STAR compatible radios are manufactured by
Icom,
Kenwood, and FlexRadio Systems.
History
In 1998 an investigation into finding a new way of bringing digital technology to amateur radio was started. The process was funded by a ministry of the Japanese government, then called the
Ministry of Posts and Telecommunications, and administered by the
Japan Amateur Radio League. In 2001, D-STAR was published as the result of the research.
In September 2003 Icom named Matt Yellen, KB7TSE (now K7DN), to lead its US D-STAR development program.
Starting in April 2004 Icom began releasing new "D-STAR optional" hardware. The first to be released commercially, was a 2-meter mobile unit designated IC-2200H. Icom followed up with 2 meter and 440 MHz handheld transceivers the next year. However, the yet to be released UT-118 add-on card was required for these radios to operate in D-STAR mode. Eventually, the card became available and once installed into the radios, it provided D-STAR connectivity. The June 2005 edition of the
American Radio Relay League
The American Radio Relay League (ARRL) is the largest membership association of amateur radio enthusiasts in the United States. ARRL is a non-profit organization and was co-founded on April 6, 1914, by Hiram Percy Maxim and Clarence D. Tuska of ...
's ''
QST'' magazine reviewed the Icom IC-V82.
JARL released some changes to the existing D-STAR standard in late 2004. Icom, aware that the changes were coming, delayed the release of their hardware in anticipation of the changes.
The Icom ID-1 1.3 GHz mobile radio was released in late 2004. The ID-1 was the first D-STAR radio that provided digital data (DD) mode operation. In this mode, data can be transferred at 128 kbit/s as a wireless bridge via the RJ-45 Ethernet jack on the radios. It was the only radio to provide this function until the release of the IC-9700 in 2019.
The first D-STAR
satellite
A satellite or an artificial satellite is an object, typically a spacecraft, placed into orbit around a celestial body. They have a variety of uses, including communication relay, weather forecasting, navigation ( GPS), broadcasting, scient ...
QSO occurred between Michael, N3UC, in
Haymarket, Virginia
Haymarket is a town in Prince William County, Virginia, United States. The population was 1,545 as of the 2020 census.
History
Haymarket is built on land that used to be hunting grounds of the western Iroquois nations, who came from the New Y ...
and Robin, AA4RC, in
Atlanta, Georgia
Atlanta ( ) is the List of capitals in the United States, capital and List of municipalities in Georgia (U.S. state), most populous city in the U.S. state of Georgia (U.S. state), Georgia. It is the county seat, seat of Fulton County, Georg ...
while working AMSAT's AO-27 microsatellite (
Miniaturized satellite
A small satellite, miniaturized satellite, or smallsat is a satellite of low mass and size, usually under . While all such satellites can be referred to as "small", different classifications are used to categorize them based on mass. Satellites c ...
) in 2007. The two experienced minor difficulty with
doppler shift
The Doppler effect (also Doppler shift) is the change in the frequency of a wave in relation to an observer who is moving relative to the source of the wave. The ''Doppler effect'' is named after the physicist Christian Doppler, who described t ...
during the QSO.
As of late 2009, there are around 10,800 D-STAR users talking through D-STAR repeaters with Internet connectivity via the G2 Gateway. There are approximately 550 G2 enabled repeaters now active. Note, these numbers do not include users with D-STAR capabilities that are not within range of a repeater, or working through D-STAR repeaters that do not have Internet connectivity.
The first D-STAR capable microsatellite was launched in early 2016. OUFTI-1 is a
CubeSat
A CubeSat is a class of small satellite with a form factor of cubes. CubeSats have a mass of no more than per unit,, url=https://static1.squarespace.com/static/5418c831e4b0fa4ecac1bacd/t/5f24997b6deea10cc52bb016/1596234122437/CDS+REV14+2020-07-3 ...
built by Belgian students at the
University of Liège
The University of Liège (), or ULiège, is a major public university of the French Community of Belgium founded in 1817 and based in Liège, Wallonia, Belgium. Its official language is French (language), French.
History
The university was foun ...
and I.S.I.L (
Haute École de la Province de Liège). The name is an acronym for ''Orbital Utility For Telecommunication Innovation''. The goal of the project is to develop expertise in various aspects of satellite design and operation.
The satellite weighs just 1 kilogram and utilizes a UHF uplink and a VHF downlink.
In 2015, FlexRadio Systems added D-STAR support to their line of
HF transceivers and receivers via a software upgrade. D-STAR support requires the addition of the ThumbDV device from NW Digital Radio.
Technical details
The system today is capable of linking
repeater
In telecommunications, a repeater is an electronic device that receives a signal and retransmits it. Repeaters are used to extend transmissions so that the signal can cover longer distances or be received on the other side of an obstruction. Some ...
s together locally and through the Internet utilizing callsigns for routing of traffic. Servers are linked via
TCP/IP
The Internet protocol suite, commonly known as TCP/IP, is a framework for organizing the communication protocols used in the Internet and similar computer networks according to functional criteria. The foundational protocols in the suite are ...
utilizing proprietary "gateway" software, available from Icom. This allows amateur radio operators to talk to any other amateurs participating in a particular gateway "trust" environment. The current master gateway in the United States is operated by the K5TIT group in Texas, who were the first to install a D-STAR repeater system in the U.S.
D-STAR transfers both voice and data via digital encoding over the
2 m (VHF),
70 cm (UHF), and
23 cm (1.3 GHz) amateur radio bands. There is also an interlinking radio system for creating links between systems in a local area on 10 GHz, which is valuable to allow emergency communications oriented networks to continue to link in the event of internet access failure or overload.
Within the D-STAR Digital Voice protocol standards (DV), voice audio is encoded as a 3,600 bit/s data stream using proprietary
AMBE
An ambe, in anatomy, is a superficial jutting out of a bone.
Ambe is also the name of an old surgical instrument, made famous by Hippocrates, for reducing dislocations of the shoulder, so called because its extremity projects like the prominence ...
encoding, with 1,200 bit/s FEC, leaving 1,200 bit/s for an additional data "path" between radios utilizing DV mode. On air bit rates for DV mode are 4,800 bit/s over the 2 m, 70 cm and 23 cm bands.
In addition to digital voice mode (DV), a Digital Data (DD) mode can be sent at 128 kbit/s only on the 23 cm band. A higher-rate data protocol, currently believed to be much like
ATM, is used in the 10 GHz "link" radios for site-to-site links.
Radios providing DV data service within the low-speed voice protocol variant typically use an
RS-232
In telecommunications, RS-232 or Recommended Standard 232 is a standard introduced in 1960 for serial communication transmission of data. It formally defines signals connecting between a ''DTE'' (''data terminal equipment'') such as a compu ...
or
USB
Universal Serial Bus (USB) is an industry standard, developed by USB Implementers Forum (USB-IF), for digital data transmission and power delivery between many types of electronics. It specifies the architecture, in particular the physical ...
connection for low-speed data (1,200 bit/s), while the Icom ID-1 and IC-9700 radios offer a standard
Ethernet
Ethernet ( ) is a family of wired computer networking technologies commonly used in local area networks (LAN), metropolitan area networks (MAN) and wide area networks (WAN). It was commercially introduced in 1980 and first standardized in 198 ...
connection for high-speed (128 kbit/s) connections on the 23 cm band. This allows easy interfacing with computer equipment.
Gateway server
The current gateway control software rs-rp2c version G2, more commonly called "Gateway 2.0". Though most Linux distributions should be suitable, the recommended configuration uses CentOS Linux 5.1 with the latest updates, typically running (
kernel
Kernel may refer to:
Computing
* Kernel (operating system), the central component of most operating systems
* Kernel (image processing), a matrix used for image convolution
* Compute kernel, in GPGPU programming
* Kernel method, in machine learnin ...
2.4.20.
glibc
The GNU C Library, commonly known as glibc, is the GNU Project implementation of the C standard library. It provides a wrapper around the system calls of the Linux kernel and other kernels for application use. Despite its name, it now also dir ...
2.3.2 and
BIND
BIND () is a suite of software for interacting with the Domain Name System (DNS). Its most prominent component, named (pronounced ''name-dee'': , short for ''name Daemon (computing), daemon''), performs both of the main DNS server roles, acting ...
9.2.1 or later). The CPU should be 2.4 GHz or faster and the memory should at least be 512 MB or greater. There should be two
network interface card
A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter and physical network interface) is a computer hardware component that connects a computer to a computer network.
Early network interface ...
s and at least 10 GB free of hard drive space which includes the OS install. Finally for middleware,
Apache
The Apache ( ) are several Southern Athabaskan language-speaking peoples of the Southwestern United States, Southwest, the Southern Plains and Northern Mexico. They are linguistically related to the Navajo. They migrated from the Athabascan ho ...
2.0.59,
Tomcat 5.5.20, mod_jk2 2.0.4,
OpenSSL
OpenSSL is a software library for applications that provide secure communications over computer networks against eavesdropping, and identify the party at the other end. It is widely used by Internet servers, including the majority of HTTPS web ...
0.9.8d,
Java SE
Java Platform, Standard Edition (Java SE) is a computing platform for development and deployment of portable code for desktop and server environments. Java SE was formerly known as Java 2 Platform, Standard Edition (J2SE).
The platform uses th ...
5.0 and
postgreSQL
PostgreSQL ( ) also known as Postgres, is a free and open-source software, free and open-source relational database management system (RDBMS) emphasizing extensibility and SQL compliance. PostgreSQL features transaction processing, transactions ...
8.2.3 are utilized, but these can be different as updates occur.
Along with the open-source tools, the Icom proprietary dsipsvd or "D-STAR IP Service Daemon" and a variety of
crontab entries utilize a mixture of the local PostgreSQL and BIND servers to look up callsigns and "pcname" fields (stored in BIND) which are mapped to individual 10.x.x.x internal-only addresses for
routing
Routing is the process of selecting a path for traffic in a Network theory, network or between or across multiple networks. Broadly, routing is performed in many types of networks, including circuit-switched networks, such as the public switched ...
of both voice and data traffic between participating gateways.
During installation, the Gateway 2.0 software installation
script
Script may refer to:
Writing systems
* Script, a distinctive writing system, based on a repertoire of specific elements or symbols, or that repertoire
* Script (styles of handwriting)
** Script typeface, a typeface with characteristics of handw ...
builds most of the Web-based open-source tools from source for standardization purposes, while utilizing some of the
packages of the host Linux system, thus making CentOS 5.1 the common way to deploy a system, to keep incompatibilities from occurring in both package versions and configuration.
Additionally, gateways operating on the U.S. trust server are asked during initial setup to install DStarMonitor which is an add-on tool that allows the overall system administrators to see the status of each Gateway's local clock and other processes and
PIDs needed for normal system operation, and also sends traffic and other data to servers operated under the domain name of "dstarusers.org". By this means a complete tracking of user behaviour is technically possible. Installation of this software also includes JavaAPRSd, a Java-based
APRS interface which is utilized on Gateway 2.0 systems to interface between the Icom/D-STAR GPS tracking system called DPRS to the more widely known and utilized amateur radio APRS system.
How Gateway G2 works
Each participating amateur station wanting to use repeaters/gateways attached to a particular trust server domain must "register" with a gateway as their "home" system, which also populates their information into the trust server—a specialized central gateway system—which allows for
lookup
In computer science, a lookup table (LUT) is an array that replaces runtime computation of a mathematical function with a simpler array indexing operation, in a process termed as ''direct addressing''. The savings in processing time can be sig ...
s across a particular trust server domain. Only one "registration" per trust domain is required. Each amateur is set aside eight 10.x.x.x internal
IP address
An Internet Protocol address (IP address) is a numerical label such as that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface i ...
es for use with their callsign or radios, and various naming conventions are available to utilize these addresses if needed for specialized callsign
routing
Routing is the process of selecting a path for traffic in a Network theory, network or between or across multiple networks. Broadly, routing is performed in many types of networks, including circuit-switched networks, such as the public switched ...
. Most amateurs will need only a handful of these "registered" IP addresses, because the system maps these to callsigns, and the callsign can be entered into multiple radios.
The gateway machine controls two
network interface controller
A network interface controller (NIC, also known as a network interface card, network adapter, LAN adapter and physical network interface) is a computer hardware component that connects a computer to a computer network.
Early network interface ...
s, the "external" one being on a real 10.x.x.x network behind a router. A router that can perform
network address translation
Network address translation (NAT) is a method of mapping an IP address space into another by modifying network address information in the IP header of packets while they are in transit across a traffic Router (computing), routing device. The te ...
on a single public IP address (can be static or dynamic in Gateway G2 systems) to a full 10.x.x.x/8 network is required. From there, the Gateway has another NIC connected directly to the D-STAR repeater controller via
10BASE-T
1 (one, unit, unity) is a number, numeral, and glyph. It is the first and smallest positive integer of the infinite sequence of natural numbers. This fundamental property has led to its unique uses in other fields, ranging from science to sp ...
and the typical configuration is a 172.16.x.x (/24) pair of addresses between the gateway and the controller.
Differences between Gateway V1 and G2
The main differences between Gateway V1 and V2 are the addition of a
relational database
A relational database (RDB) is a database based on the relational model of data, as proposed by E. F. Codd in 1970.
A Relational Database Management System (RDBMS) is a type of database management system that stores data in a structured for ...
(
PostgreSQL
PostgreSQL ( ) also known as Postgres, is a free and open-source software, free and open-source relational database management system (RDBMS) emphasizing extensibility and SQL compliance. PostgreSQL features transaction processing, transactions ...
) for more flexibility and control of updates, versus the previous use of only
BIND
BIND () is a suite of software for interacting with the Domain Name System (DNS). Its most prominent component, named (pronounced ''name-dee'': , short for ''name Daemon (computing), daemon''), performs both of the main DNS server roles, acting ...
for "database" activities, the addition of both an administrative and end-user Web interface for registration which was previously handled via
command-line
A command-line interface (CLI) is a means of interacting with software via commands each formatted as a line of text. Command-line interfaces emerged in the mid-1960s, on computer terminals, as an interactive and more user-friendly alternativ ...
commands by the Gateway V1 system administrators, dropping the requirement for static public
IP address
An Internet Protocol address (IP address) is a numerical label such as that is assigned to a device connected to a computer network that uses the Internet Protocol for communication. IP addresses serve two main functions: network interface i ...
es for
gateways, and the ability of the software to use a
fully qualified domain name
A fully qualified domain name (FQDN), sometimes also called an absolute domain name, is a domain name that specifies its exact location in the tree hierarchy of the Domain Name System (DNS). It specifies all domain levels, including the top-level ...
to find and communicate with the trust server, allowing for redundancy/failover options for the trust server administrators. Finally, a feature called "multicast" has been added for administrators to be able to provide users with a special "name" they can route calls to which will send their transmissions to up to ten other D-STAR repeaters at the same time. With cooperation between administrators, a "multicast group" can be created for multiple repeater networks or other events.
Another additional feature of Gateway G2 is the ability to use callsign "suffixes" appended to the user's callsign in a similar fashion to the repeaters and gateways in the original system, which allow for direct routing to a particular user's radio or between two user radios with the same base callsign, by utilizing the 8th most significant field of the callsign and adding a letter to that location, both in the gateway registration process on the web interface, and in the radios themselves.
Gateway V1 control software
The Gateway V1 software was similar to Gateway G2, and utilized Fedora Core 2+ or Red Hat Linux 9+ OS on a Pentium-grade 2.4 GHz or faster machine.
IrcDDBGateway
Gateway software developed by Jonathan Naylor, G4KLX, has a larger network of repeaters and users and is being adopted by former Gateway G2 users as the G2 system is closed source, only supports Icom repeaters, and runs on Centos 5.x which will reach end of life in March 2017. ircDDBGateway operates on the ircDDB and QuadNet2 networks and is licensed under
GPL-2.0.
ircDDBGateway supports Icom controllers and repeaters, as well as homebrew repeaters and hotspots (simplex access points). It provides more linking and routing options over the Gateway V1 and G2.
ircDDBGateway can run on various distributions of Linux and versions of Microsoft Windows. Computer requirements can be as simple as a
Raspberry Pi
Raspberry Pi ( ) is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in collaboration with Broadcom Inc., Broadcom. To commercialize the product and support its growing demand, the ...
.
DStarGateway
Refactored ircDDBGateway by Geoffery Merck F4FXL. Known to support Icom 3rd Generation repeaters.
Add-on software
Various projects exist for gateway administrators to add "add-on" software to their gateways, including the most popular package called "dplus" created by Robin Cutshaw AA4RC. A large number of Gateway 2.0 systems are offering services added by this software package to their end-users, and users are getting used to having these features. Features include the ability to link systems directly, "voice mail" (a single inbox today), ability to play/record audio to and from the repeaters connected to the Gateway and the most important, the ability for DV-Dongle users to communicate from the Internet to the radio users on the repeaters.
There is often a misconception by users and system administrators alike that the Gateway 2.0 systems have these add-on features from dplus by default, a testament to the popularity of this add-on software. Dplus software development has an active following, and features such as multiple repeater/system connections similar to the type of linking done by other popular repeater-linking systems (
IRLP and
EchoLink
EchoLink is a computer-based amateur radio system distributed free of charge that allows radio amateurs to communicate with other amateur radio operators using Voice over IP (VoIP) technology on the Internet for at least part of the path between t ...
) are being worked on.
Criticisms
;Proprietary codec
Like other commercial digital modes (
P25,
TETRA
Tetra is the common name of many small freshwater characiform fishes. Tetras come from Africa, Central America, and South America, belonging to the biological families Characidae, Alestidae (the "African tetras"), Lepidarchidae, Lebiasi ...
,
DMR,
dPMR,
NXDN,
System Fusion), D-STAR uses a closed-source proprietary voice codec (
AMBE
An ambe, in anatomy, is a superficial jutting out of a bone.
Ambe is also the name of an old surgical instrument, made famous by Hippocrates, for reducing dislocations of the shoulder, so called because its extremity projects like the prominence ...
) that's patented by Digital Voice Systems, Inc. (DVSI) because it was the highest quality and only codec available in silicon when the system was released. Amateur radio operators do not have access to the specification of this codec or the rights to implement it on their own without buying a licensed product. Amateurs have a long tradition of building, improving upon and experimenting with their own radio designs. The modern digital age equivalent of this would be designing and/or implementing codecs in software. Critics say the proprietary nature of AMBE and its availability only in hardware form (as ICs) discourages innovation. Even critics praise the openness of the rest of the D-STAR standard which can be implemented freely. As of 2017 the patents have expired, as announced by Bruce Perens, K6BP at the 2017 ARRL/TAPR DCC in his State of Digital Voice talk.
;Trademarked name
The term 'D-STAR' is itself a registered
trademark
A trademark (also written trade mark or trade-mark) is a form of intellectual property that consists of a word, phrase, symbol, design, or a combination that identifies a Good (economics and accounting), product or Service (economics), service f ...
of Icom. Icom also holds a trademark for its stylized D-STAR logo. There is no indication Icom is charging other vendors to use any of the D-STAR branding.
;Usable range compared to FM
D-STAR, like any digital voice mode has comparable usable range to FM, but it degrades differently. While the quality of FM progressively degrades the farther a user moves away from the source, digital voice maintains a constant voice quality up to a point, then essentially "
falls off a cliff". This behavior is inherent in any digital data system, and it demonstrates the threshold at which the signal is no longer correctable, and when data loss is too great, audio artifacts can appear in the recovered audio.
;Emergency Communications Concerns
Many advanced D-STAR features rely on internet connections although simplex, repeated and crossband gateway voice and data communications do not. During widespread disasters that compromise commercial telecommunications infrastructure, D-STAR systems (as well as other modes that rely on the internet) may suffer outages or feature degradation that impacts operations. Without simulating such outages during drills, it is difficult to assess the impact of or establish D-STAR service recovery procedures in the event of such failures. As of the fall of 2011, there has been almost no discussion in the ham radio literature regarding actual drills where D-STAR systems were tested with completely failed or even intermittent telecommunications infrastructure. Comprehensive emergency communications plans used by ARES and other such organizations should address the possibility that such systems may not function as intended during major disasters.
The loss of Internet does not degrade the local operation of a D-STAR repeater system. Over the Internet linking and routing of traffic may be degraded. Some groups are using microwave-based systems, such as HamWAN, to link repeaters.
;Cost
In
Icom's radio line, D-STAR used to significantly add to the cost of a radio, which was a barrier to the adoption of the technology. While in 2006 the cost of a D-STAR radio was compared to that of a standard analog radio, and the price difference was nearly double, in 2024 D-STAR is standard fare in many amateur radio transceivers, fixed-base (Icom IC-9700), mobile (Icom IC-7100) and hand-held (Icom IC-705, IC-905, IC-50A and IC-52A).
This decrease in price is due to the per-unit cost for the voice codec hardware and/or license and partly to manufacturer research and development costs that has now been amortized. As is the case with any product, as more units were sold, the R&D portion of the cost decreased over time.
FlexRadio Systems D-STAR implementation requires the use of a $129 add-on module to their FLEX-6000 Series Radios.
;Questionable legality
Many have argued that the proprietary codec constitutes a form of encryption, and encryption is prohibited by almost every country's amateur radio licence conditions. According to FCC rules, if the algorithm is publicly published or otherwise widely available enough that transmissions are not secret, it is considered encoding rather than encryption. Unfortunately D-STAR uses AMBE, a non-public codec. However, French regulators, in April 2010, have issued a statement that rules D-STAR illegal in France, due to the ability to create a connection to the internet with it and the proprietary nature of the codec used. The French Amateur Radio society, DR@F - Digital Radioamateur France has an online petition against this ruling, calling for the government to allow the mode, as to ban it would deny them 'fundamental rights'.
Non-Icom D-STAR repeaters
The world's first non-Icom D-Star repeater was developed by KB9KHM using a GMSK Node Adaptor developed by Satoshi Yasuda and DVAR Hotspot software developed by KB9KHM in 2008. This repeater could link over the Internet with other Icom repeater gateways and Reflectors via D-Plus. It did not support callsign routing or slash routing via the K5TIT G2 network.
The first non-Icom D-STAR repeater fully supporting the K5TIT G2 network and D-Plus, GB7MH, went live on 10 September 2009, in West Sussex, England.
Whilst waiting for the DSL line installation, the repeater is connected to the Internet via a 3G dongle from network operator "Three".
The system is built around Satoshi Yasuda's GMSK Node Adapter, a Mini-ITX system running CentOS 4, a Tait T800 repeater and G2 code written by G4ULF.
All the usual G2 features such as callsign routing, D-Plus linkage and DPRS via D-STAR Monitor are supporte
https://www.qsl.net/rvarc/files/WS4VA_D-STAR_Presentation.pd
Today a home-brewed D-STAR repeater can be built using open source software, used commercial radio equipment and a computer. One group advocating the construction of home-brewed D-STAR repeaters is Free-Star. Free-Star is an experimental approach to the implementation of a vendor neutral, and open source, digital communication network for amateur radio.
GB7LF in Lancaster, UK, went live in May 2009 and was a converted Tait repeater. It was preceded by two others in Weston-Super-Mare, UK and also another in Staffordshire, U
Compatible programs and projects
;D-StarLet
A Web-based text messaging application using D-STAR digital data technology.
D-StarLet is an open source client-server solution that allows content creation and modification from certain persons. D-StarLet interfaces with a D-STAR radio through the serial port. It works with Windows (98+), Linux (Red Hat 7.3+), Apple
Mac OS X
macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...
, and others.
;D-PRS interface
D-PRS is GPS for ham radio. Includes DStarTNC2, javAPRSSrvr, DStarInterface, and TNC-X
;DStarMonitor
A Java application run on the repeater gateway PC which logs activity on the attached repeaters. Additional features include APRS object representation of each repeater.
;DStarQuery
DStarQuery monitors the low-speed data stream of a D-STAR radio looking for queries sent from a remote station. When a valid query is received, a predefined sequence is executed and the results transmitted from the station running DStarQuery. For example, a station transmits "?D*rptrs?" and it is received by a DStarQuery station which responds with a list of local repeaters.
The program D-PRS Interface includes a "Query" entry field that streamlines this process allowing the user to simply enter the desired command. Most DStarQuery systems will respond with a list of available commands when "?D*info?" is received.
;D-STAR Comms PRO
An advanced software application for use with D-STAR enabled radios. Supports advanced text chat, personal messaging with auto-reply and inbox, e-mail gateway and a beacon mode. GPS Tracking / Logging and a GPS Beacon emulator and Internet linking. New features are added weekly and users can suggest new features through the D-STAR Comms forum. www.dstarcomms.com
;D-STAR Star TV
Slow Scan TV for D-STAR radios and video streaming for Icom ID-1 by GM7HHB. Runs on Windows XP and Vista.
;D-RATS
D-RATS is a D-STAR communications tool that supports
text chat
Instant messaging (IM) technology is a type of synchronous computer-mediated communication involving the immediate ( real-time) transmission of messages between two or more parties over the Internet or another computer network. Originally involv ...
, TCP/IP forwarding,
file transfer
File transfer is the transmission of a computer file through a communication channel from one computer system to another. Typically, file transfer is mediated by a communications protocol. In the history of computing, numerous file transfer protoc ...
s, and can act as an
e-mail gateway. There is also the ability to map user's positions using the D’PRS function of D-STAR. The application is written in
Python
Python may refer to:
Snakes
* Pythonidae, a family of nonvenomous snakes found in Africa, Asia, and Australia
** ''Python'' (genus), a genus of Pythonidae found in Africa and Asia
* Python (mythology), a mythical serpent
Computing
* Python (prog ...
/
GTK
GTK (formerly GIMP ToolKit and GTK+) is a free software cross-platform widget toolkit for creating graphical user interfaces (GUIs). It is licensed under the terms of the GNU Lesser General Public License, allowing both Free software, free and ...
and is
cross-platform
Within computing, cross-platform software (also called multi-platform software, platform-agnostic software, or platform-independent software) is computer software that is designed to work in several Computing platform, computing platforms. Some ...
. It runs on Windows, Mac OS X, and Linux. The application was developed by Dan Smith (KK7DS) for the Washington County Amateur Radio Emergency Service in Oregon.
D-STAR is able to send data to
emergency responders in the event of a disaster. Served agencies can relate to sending
e-mail
Electronic mail (usually shortened to email; alternatively hyphenated e-mail) is a method of transmitting and receiving Digital media, digital messages using electronics, electronic devices over a computer network. It was conceived in the ...
or other documents to someone. The quantity of data sent can be higher compared to traditional amateur modes. Voice and even
CW are capable of getting a message through albeit slowly, but D-STAR can transfer documents, images, and
spreadsheet
A spreadsheet is a computer application for computation, organization, analysis and storage of data in tabular form. Spreadsheets were developed as computerized analogs of paper accounting worksheets. The program operates on data entered in c ...
s.
It was in the
Great Coastal Gale of 2007 the Washington County ARES group was able to test D-STAR during this series of several strong Pacific storms that interrupted conventional communication systems for up to one week. Primary emergency traffic for the
American Red Cross
The American National Red Cross is a Nonprofit organization, nonprofit Humanitarianism, humanitarian organization that provides emergency assistance, disaster relief, and disaster preparedness education in the United States. Clara Barton founded ...
and the
Vernonia, Oregon
Vernonia is a city in Columbia County, Oregon, United States. It is located on the Nehalem River, in a valley on the eastern side of the Northern Oregon Coast Range that is the heart of one of the most important timber-producing areas of the ...
Fire Department was handled by the group using traditional FM voice because the group had no D-STAR repeater equipment available. Once the situation's communication needs became established the D*Chat messaging function was used to send small text transmissions via D-STAR
simplex
In geometry, a simplex (plural: simplexes or simplices) is a generalization of the notion of a triangle or tetrahedron to arbitrary dimensions. The simplex is so-named because it represents the simplest possible polytope in any given dimension. ...
at distances of up to seventeen miles.
An ability for amateurs to send files during this weather event would have greatly increased the capacity for ARES to help during the emergency.
Although D*Chat was a useful means of communication D-RATS was developed to help fill the gaps that may have been lacking.
Another improvement over D*Chat that D-RATS provides is form support. Users can set up frequently used forms well before they are necessary and when the need comes all that is required is to fill in the fields. In this way, for example, emergency forms from the
Red Cross
The organized International Red Cross and Red Crescent Movement is a Humanitarianism, humanitarian movement with approximately 16million volunteering, volunteers, members, and staff worldwide. It was founded to protect human life and health, to ...
,
National Traffic System
The National Traffic System (NTS) is an organized network of amateur radio operators sponsored by the American Radio Relay League for the purpose of relaying messages throughout the U.S. and Canada.
During normal times, these messages are rout ...
, or the
Incident Command System
The Incident Command System (ICS) is a standardized approach to the command, control, and coordination of emergency response providing a common hierarchy within which responders from multiple agencies can be effective.
ICS was initially develop ...
, such as the FEMA standard ICS-213, could be generated and sent.
Home-brew D-STAR radio
The first presumed D-STAR radio including pictures and diagrams can be found at Moetronix.com's Digital Voice Transceiver Project. This page includes the schematic, source, and whitepaper.
Another project is Satoshi Yasuda's (7M3TJZ/AD6GZ) experiments with a UT-118 DV adapter. This project involves interfacing Icom's UT-118 with other manufacturer's amateur radio transceivers. With this project some VHF/UHF/SHF amateur radio transceivers are capable of being adapted for D-STAR operation. This requires access to the receiver's discriminator and to the direct FM modulator of the radio, sometimes available at a 9,600 bit/s packet interface. Satoshi's product is no longer available. There is an alternative available at www.
Antoni Navarro (EA3CNO) also has designed another interface based on a PIC microprocessor and UT-118 module.
With the rise of cheap RTL-chip based Software Defined Radios, there also appeared various software decoders to decode digital speech information carried by radio signals. Recently, this also includes D-Star. There are third-party decoders available, either for the protocol data and for the digital speech content, but legal conflicts with the patented AMBE vocoder may exist in some jurisdictions.
Equipment
*Homebrew
**Decoder/Receivers:
***Reception done by a Software Defined Radio and decoding of the D-Star header information done by the program dstar.exe.
***Reception done by a Software Defined Radio and speech decoding done by the program DSD 1.7 (Digital Speech Decoder).
**Repeater equipment:
***GMSK Node Adapter - these devices are hardware GMSK modems with firmware to take D-STAR protocol frames over a USB cable and provide the necessary logic and GMSK modulation to control a simplex node or a full duplex repeater. One repeater that is easily adaptable is the Kenwood TKR-820 as documented by K7VE.
***GMSK using a sound card - this method uses a computer sound card to generate GMSK modulation and de-modulation. The primary software for this method is developed by Jonathan Naylor. An example of a repeater system using this technique is the addition of D-STAR to the
Yaesu
is a district in Chūō, Tokyo, Japan, located north of Ginza, west of Nihonbashi and Kyōbashi, and adjacent to the east side of Tokyo Station. The Yaesu exit of this station, which faces Nihonbashi, is a recent addition and primarily provide ...
DR-1X repeater by attaching the UDRC and a
Raspberry Pi
Raspberry Pi ( ) is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in collaboration with Broadcom Inc., Broadcom. To commercialize the product and support its growing demand, the ...
computer.
*Icom D-STAR equipment
**Transceivers—D-STAR and Analog FM Capable:
***Icom ID-1: 23 cm digital voice and digital data mobile transceiver. Power is selectable at 1 W or 10 W. USB control port and Ethernet connection for data. No longer available.
***Icom IC-2820H/IC-E2820: 2 m / 70 cm twin band digital voice mobile transceiver. Power up to 50 W on each band. May be purchased with or without UT-123 D-STAR module. The D-STAR module includes a built-in GPS receiver with accompanying antenna.
***Icom ID-31 and ID-31A: 70 cm digital voice hand held transceiver (5W). Includes a built-in GPS receiver and repeater database.
***Icom ID-51 and ID-51A: 2 m / 70 cm dual band digital voice hand held transceiver (5W). Includes a built-in GPS receiver and DSTAR repeater database. Also reception of broadcast FM, AM, and shortwave.
***Icom ID-51 Anniversary Edition and ID-51A Plus: 2 m / 70 cm dual band digital voice hand held transceiver (5W). Identical to ID-51A but adds FM repeater directory and higher speed (3600 bit/s) DV data mode.
***Icom ID-51 and ID-51A Plus 2: identical to ID-51A Plus but adds Access point and Terminal mode.
***
Icom IC-705: HF/VHF/UHF 5w/10w Users can enjoy the latest G3 Gateway and DV mode features and have direct access to the D-STAR network with Terminal/Access point modes. The Photo Share feature as seen in the IC-9700 is available on the IC-705 to share photos with other IC-705 and IC-9700 radios without a computer.
***Icom ID-800H: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 55 W on 2 m and 50 W on 70 cm.
***Icom ID-880H: 3rd gen 2 m / 70 cm digital voice mobile transceiver (50W).
***Icom IC-80AD: 3rd gen 2m / 70 cm digital voice hand held transceiver (5W).
***Icom IC-92AD: 2 m / 70 cm twin band digital voice hand held transceiver. Four power settings up to 5 W on each band. Rugged and submersible design, optional microphone with embedded GPS.
***Icom IC-91AD/IC-E91 + D-STAR: 2 m / 70 cm twin band digital voice hand held transceiver. Power is selectable at 0.5 W or 5 W on each band.
***
Icom IC-905: VHF/UHF/SHF transceiver announced recently by ICOM.
***Icom IC-2200H: 2 m single band digital voice mobile transceiver. Power up to 65 W. Must purchase optional D-STAR module.
***Icom IC-V82: 2 m single band digital voice hand held transceiver. Power up to 7 W. Must purchase optional D-STAR module.
***Icom IC-U82: 70 cm single band digital voice hand held transceiver. Power up to 5 W. Must purchase optional D-STAR module.
***
Icom IC-9100: HF/VHF/UHF transceiver. Must purchase optional UT-121 D-STAR module.
***Icom IC-9700: 2 m / 70 cm / 23 cm All Mode. Includes the Digital Data Mode found in the discontinued ID-1. Can decode two digital voice streams at once.
***Icom IC-7100: HF/VHF/UHF transceiver. Includes built-in D-STAR capability and monochrome touchscreen.
***Icom ID-4100A: 2 m / 70 cm twin band digital voice mobile transceiver with monochrome touchscreen. Power up to 50 W. Air band, Marine, Weather RX. Terminal and assess point mode GPS receiver. microSD slot for voice and logging
***Icom ID-5100: 2 m / 70 cm twin band digital voice mobile transceiver with monochrome touchscreen. Power up to 50 W on each band. Includes D-STAR module standard with GPS receiver and antenna in the head. Higher speed (3600 bit/s) DV data mode possible with firmware upgrade.
**Receivers:
***Icom IC-R2500: HF/VHF/UHF/SHF receiver/scanner. Must purchase optional D-STAR module.
***Icom IC-R30: HF/VHF/UHF/SHF receiver/scanner
**Repeater equipment:
***Icom ID-RP2000V: 2 m digital voice repeater.
***Icom ID-RP4000V: 70 cm digital voice repeater.
***Icom ID-RP2V: 23 cm digital voice repeater.
***Icom ID-RP2D: 23 cm digital data access point.
***Icom ID-RP2C: Repeater controller. Can support up to four digital voice repeaters and digital data access points. Required to operate any Icom D-STAR digital voice repeater or digital data access point.
***Icom ID-RP2L: 10 GHz Microwave Link Repeater.
*FlexRadio Systems D-STAR equipment
**Transceivers—D-STAR, CODEC2, Analog FM Capable and all mode:
***FLEX-6700: HF-2m all mode including digital voice transceiver (8 receivers). Power is selectable from 1 W to 100 W. Open API including D-STAR access. D-STAR source available online
***FLEX-6500: HF-4m all mode including digital voice transceiver (4 receivers). Power is selectable from 1 W to 100 W. Open API including D-STAR access. D-STAR source available online
***FLEX-6300: HF-6m all mode including digital voice transceiver (2 receivers). Power is selectable from 1 W to 100 W. Open API including D-STAR access. D-STAR source available online
**Receivers:
***FLEX-6700R: HF-2m all mode including digital voice receiver (8 receivers). Open API including D-STAR access. D-STAR source available online
::Note: ''These transceivers are not available in North America and appear to be OEM versions of the Icom ID-800H''
*Kenwood D-STAR equipment
**Transceivers:
*** Kenwood TH-D74: 2 m / 70 cm dual band handheld with digital voice and
APRS.
*** Kenwood TH-D74A: 2 m / 1.25 m / 70 cm tri band handheld with digital voice and
APRS.
*** Kenwood TH-D74E: 2 m / 70 cm dual band handheld with digital voice and
APRS.
*** Kenwood TH-D75: 2 m / 70 cm dual band handheld with digital voice and
APRS.
*** Kenwood TH-D75A: 2 m / 1.25 m / 70 cm tri band handheld with digital voice and
APRS.
*** Kenwood TH-D75E: 2 m / 70 cm dual band handheld with digital voice and
APRS.
*** Kenwood TMW-706: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 20 W.
*** Kenwood TMW-706S: 2 m / 70 cm dual band digital voice mobile transceiver. Power up to 50 W.
*AOR
**Receivers:
***AOR AR-DV1: Wide band receiver (100 kHz - 1300 MHz) that decodes multiple digital voice modes including D-STAR
***AOR AR-DV10: Wide band receiver (100 kHz - 1300 MHz) that decodes multiple digital voice modes including D-STAR
*Inet Labs
**Computer accessory:
***DV-Dongle: The dongle is a
USB
Universal Serial Bus (USB) is an industry standard, developed by USB Implementers Forum (USB-IF), for digital data transmission and power delivery between many types of electronics. It specifies the architecture, in particular the physical ...
device with the
AMBE
An ambe, in anatomy, is a superficial jutting out of a bone.
Ambe is also the name of an old surgical instrument, made famous by Hippocrates, for reducing dislocations of the shoulder, so called because its extremity projects like the prominence ...
codec built in. Amateurs can use this with a personal computer's audio system to communicate over the D-STAR network. This is an option for using D-STAR if there is not a local D-STAR repeater or if there is a repeater but it is not associated with an Internet gateway.
The dongle works along with the DVTOOL software, a simple application that mimics the controls on a D-STAR radio, although the interface does not actually look like a radio panel. Note: Now available from a number of amateur radio dealers or by homebrew using documentation at Moetronix.
*** DV-AP: A DVAP Dongle (DV Access Point Dongle) is also a USB device that creates a connection to the D-STAR network through an Internet connected computer. But instead of using the computer's audio system, the DVAP Dongle has an antenna and a 10 mW two-meter transceiver that provides short-range over-the-air access using a D-STAR radio (usually a handheld). Note that a D-STAR radio is required. The DVAP does ''not'' convert an analog FM signal to D-STAR.
*NW Digital Radio
**Computer accessory:
***ThumbDV D-STAR DV USB is a
USB
Universal Serial Bus (USB) is an industry standard, developed by USB Implementers Forum (USB-IF), for digital data transmission and power delivery between many types of electronics. It specifies the architecture, in particular the physical ...
device with the
AMBE
An ambe, in anatomy, is a superficial jutting out of a bone.
Ambe is also the name of an old surgical instrument, made famous by Hippocrates, for reducing dislocations of the shoulder, so called because its extremity projects like the prominence ...
codec built in. Amateurs can use this with a personal computer's audio system to communicate over the D-STAR network. This is an option for using D-STAR if there is not a local D-STAR repeater with a gateway.
***PiDV D-STAR DV add-on card for upcoming UDRX,
Odroid
The ODROID is a series of single-board computers and tablet computers created by Hardkernel Co., Ltd., located in South Korea. Even though the name ''ODROID'' is a portmanteau of ''open'' + ''Android'', the hardware is not actually open-source h ...
or
Raspberry Pi
Raspberry Pi ( ) is a series of small single-board computers (SBCs) developed in the United Kingdom by the Raspberry Pi Foundation in collaboration with Broadcom Inc., Broadcom. To commercialize the product and support its growing demand, the ...
that adds the
AMBE
An ambe, in anatomy, is a superficial jutting out of a bone.
Ambe is also the name of an old surgical instrument, made famous by Hippocrates, for reducing dislocations of the shoulder, so called because its extremity projects like the prominence ...
codec chip
See also
*
MDC-1200
*
Multi-Band Excitation
Multi-Band Excitation (MBE) is a series of proprietary speech coding standards developed by Digital Voice Systems, Inc. (DVSI).
Overview
In 1967 Osamu Fujimura (MIT) showed basic advantages of the multi-band representation of speech ("An App ...
*
NXDN, a related commercial two-way digital radio standard with similar characteristics
*
Project 25
Project 25 (P25 or APCO-25) is a suite of standards for interoperable Land Mobile Radio (LMR) systems designed primarily for public safety users. The standards allow analog conventional, digital conventional, digital trunked, or mixed-mode sys ...
, a related digital radio standard sponsored by
APCO
*
Ricochet modems
*
TETRA
Tetra is the common name of many small freshwater characiform fishes. Tetras come from Africa, Central America, and South America, belonging to the biological families Characidae, Alestidae (the "African tetras"), Lepidarchidae, Lebiasi ...
, a digital two-way radio standard in use outside of North America
References
Journal
* ARRL: QST ''Icom IC 2820H Dual Band FM Transceiver'' Vol 91 No 11 November 2007 Page 74, by Steve Ford, WB8IMY does a review on the IC 2820H Dual Band FM Transceiver.
*
RSGB:
RadCom
''RadCom'' is the monthly magazine published by the Radio Society of Great Britain and is provided to all corporate members of the society. Typically 100 pages, it includes a mixture of news, theory, construction and technical articles of inter ...
March 2008 (Vol 83 No 03) review of Icom IC-E2820 transceiver and overview of D-STAR.
* CQ-VHF: D-STAR in the Southeastern U.S., Greg Sarratt, W4OZK, (partial), https://web.archive.org/web/20080913225308/http://www.cq-vhf.com/D-StarWin08.html
* N1IC's Review of Icom ID-51 http://nicktoday.com/icom-id-51-id-51a-first-quick-review/
External links
Icom D-STAR Digital RadiosIcom D-STAR MicrositeD-STAR FAQ and InformationIcom D-STAR informationdstarusers.orgD-STAR videoby the Washington County ARES group
{{DEFAULTSORT:D-STAR
Digital amateur radio
Quantized radio modulation modes