D-STAR Overview

D-Star Overview

The D-STAR system provides a new capability and functionality to the ham radio world and increases the efficiency of emergency communications.

D-STAR (Digital Smart Technologies for Amateur Radio) was originally developed as the result of research by the Japan Amateur Radio League (JARL) to investigate digital technologies for Amateur Radio. Although the D-Star protocol is 'open source' and specifications available to anyone, there is currently only one equipment manufacturer that has begun manufacturing and distributing radios and repeaters, and that is ICOM.

The D-STAR system supports two types of digital data streams. The Digital Voice (DV) stream used on 144 and 440 MHz contains both digitized voice and digital data. Using a DV radio is like having both a packet link and FM voice operating simultaneously. The Digital Data (DD) stream that is used only on 1.2 GHz, is entirely data with a bit rate of 128k bps.

For voice conversations, D-STAR repeaters act just like familiar analog repeaters – everyone listening can hear your transmissions. Because your call sign is digitally incorporated into every transmission, the D-STAR repeater “registers” your call sign and shares it around the D-STAR system.

If you travel into a new D-STAR repeater’s coverage area, your location will be quickly updated around the D-STAR network on your first transmission in that area. This allows you to call someone registered with any other D-STAR repeater, no matter where that may be. If you call someone registered elsewhere, your voice will be routed to the appropriate repeater in digital form, where it is then heard just as you would expect if you were both using the same repeater!

The system today is capable of linking repeaters together locally and through the Internet utilizing callsigns for routing of traffic. Servers are currently linked via TCP/IP 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.

Another important aspect of D-STAR technology is its ability to send large quantities of data to emergency responders in the event of a disaster. Served agencies can instantly relate to sending 'email' or a 'word files' to someone. The data sent can be high-volume, where traditional amateur radio 'modes' are capable of getting a message through albeit slowly, D-STAR can place documents into the hands of those that need them most - fast image, text and document data exchanges.

Inside D-Star Digital Radio

I have created a downloadable .pdf about D-STAR Digital Radio. This will introduce you to the Digital Features of D-STAR, minor setup feature of the radio, call sign routing, and useful links to aid you in using the D-STAR Gateway.

http://www.coloradodstar.org/dl/InsideD-STARDigitalRadio.pdf

Barry Wilson KA0BBQ Founding Member Colorado D-STAR