Ham radio already makes use of many digital modes such as RTTY, PSK31, AX.25 Packet, etc. Another wave coming is a true digital voice mode, especially for the VHF and higher bands. Currently, most of the activity on the VHF and higher bands is FM (or SSB), both analog modulation. Virtually all of the mobile phone formats have gone digital and good old analog FM is being phased out. Many land mobile users such as police and fire radio are also moving to digital. I suspect it is a question of when (not if) ham radio VHF/UHF will go digital.
The two competing formats emerging in the ham radio world are D-STAR and APCO 25. D-STAR is a digital radio standard developed by the Japanese government under the direction of the JARL. ICOM is the leading proponent of D-STAR and has several transceivers and repeaters available that conform to the standard. The ICOM web site has the best information on using D-STAR. The ARRL recently did a review of a few ICOM D-STAR products in QST.
Any new technology has to overcome the fear that it won’t be broadly adopted and will die an early death. One concern is that only ICOM has D-STAR radios in the market today. Recently, there have been sightings of a D-STAR radio from Kenwood, which could indicate momentum behind the D-STAR standard. The ARRL has also reported activity from Kenwood on D-STAR transceivers.
APCO 25 is the digital radio standard aimed at police/fire/emergency responders developed by the Association of Public-Safety Communications Officials (APCO) International. APCO calls this format “Project 25” or P25, which is described here. Some hams argue that hams should once again follow the tradition of adopting commercial/land mobile developed standards for ham use. There is merit to this argument as the VHF/UHF FM gear is based on commercial standards. Even today, many repeaters are made up of commercial gear deployed on the ham bands.
Which is better, a standard developed for amateur radio use or one that leverages off commercial standards and technology? The debate is on in the various online ham forums. (Don’t expect consistently brilliant discussion of the topic.) VE7TKO has been a vocal supported of D-STAR on eham.net digital forum and qrz.com.
Stay tuned. This will be a hot topic in the years to come. And it will probably take years for digital to overtake analog….the installed base is just too large and it will take time for it to convert over.