What is D-STAR*?

D-STAR* (Digital Smart Technology for Amateur Radio), a standard published in 2001, is the result of years of research funded by the Japanese government and administered by the JARL to investigate digital technologies for amateur radio. D-STAR* is an open protocol - published by JARL, it is available to be implemented by anyone. Whilst Icom is the only company to date that manufactures D-STAR* compatible radios, any equipment or software that supports the D-STAR* protocol will work with a D-STAR* system.

In a D-STAR* system, the air link portion of the protocol applies to signals travelling directly between radios or between radios via a repeater. D-STAR* radios can talk directly to each other without any intermediate equipment or through a repeater using D-STAR* voice or data transceivers.

The gateway portion of the protocol applies to the digital interface between D-STAR* repeaters. D-STAR* also specifies how a voice signal is converted to and from the stream of digital data. The D-STAR* codec is known as AMBE® (Advanced Multiband Excitation) and the voice signal is transmitted in the D-STAR* system at 3600 bits/second (3.6 kbps).

The D-STAR* system supports two types of digital data streams. The Digital Voice (DV) stream used for example on 430-440 MHz contains both digitised voice (3600 bps including error correction) and digital data (1200 bps). Using a DV radio is like having both a packet link and FM voice operating simultaneously. The Digital Data (DD) stream, used only on 1.2 GHz, is entirely data with a bit rate of 128k bps. The data connection to a radio that uses DV is via an RS-232 interface or USB 1.0. An Ethernet connection is used for high-speed DD D-STAR data. Ordinary terminal emulation software (DV) or a Web browser (DD) will be sufficient for exchanging data.