|VOICE CODEC||3600 bps AMBE®
|DATA SPEED||DV: 1200 bps (net 950 bps)
DD: 128k bps (net 90k bps)
|LS: 1200 bps
HS: 9600 bps
||DV: Any VHF/UHF band
DD: 1.2 GHz
|Any VHF/UHF band|
||DV: RS-232 or USB 1.0
||Same as Ethernet
||7-bit ASCII text|
||D-STAR packet format and 0.5GMSK
|LS: AX.25 using Bell 202 modulation
HS: AX.25 using K9NG Bell 212A
|DV: Transparent point-to-point
|AX.25 of TCP/IP|
For low-speed DV D-STAR* links (1200 bps), the data interface to your laptop or terminal is a familiar RS-232, three-wire connection (Rx data, Tx data, and signal ground) or a USB 1.0 interface, depending on the radio. For high-speed D-STAR* (128k bps), the data interface is an Ethernet connection with the customary RJ-45 jack.
Over the air, packet signals use FSK protocols originally designed for land-line applications and adapted to amateur radio. D-STAR* uses the up-to-date modulation method of 0.5GMSK--Gaussian Minimum Shift Keying. GMSK provides improved performance over packet because it is designed for wireless links. Data is sent using the D-STAR* packet format, which includes FEC (Forward Error Correction) and routing information. The data itself is encapsulated within the D-STAR* packet as an Ethernet packet.
Low-speed DV D-STAR* data is a "keyboard-to-keyboard" mode. The D-STAR* system provides reliable, transparent transport from user to user by using CRC error detection. High-speed DD D-STAR* data appears at the data interface as an Ethernet packet suitable for encapsulation by the TCP/IP protocol stack. The Ethernet connection is a bridged, point-to-point connection between static IP addresses so that standard Internet application software can be used to transfer data across the D-STAR* system.