D-STAR (Digital Smart Technologies for Amateur Radio) is a digital voice and data protocol developed by the Japan Amateur Radio League (JARL). It is one of the major digital modes used in amateur radio, alongside DMR, Fusion (C4FM), and P25. Below are the key pros and cons of D-STAR:
Pros of D-STAR:
1. Integrated Digital Voice and Data
- D-STAR allows simultaneous voice and low-speed data transmission, making it useful for messaging and location services.
2. Wide-Area Linking via Reflectors
- D-STAR repeaters can be linked together using reflectors, allowing for worldwide communication over the internet (D-STAR calls these “DPlus Reflectors”).
3. Call Sign Routing
- Unlike some other digital modes, D-STAR allows users to call each other directly using call signs, regardless of their location in the network.
4. Dedicated Digital Design
- Unlike DMR (which was adapted from commercial radio), D-STAR was designed specifically for amateur radio, making it more tailored to the needs of hams.
5. Supports Full-Duplex Operation
- Some D-STAR radios (such as Icom’s dual-band models) support full-duplex, which can be useful for satellite operations.
6. GPS Integration
- Many D-STAR radios include built-in GPS functionality, making it easy to share location information. This is useful for APRS-like features and emergency communication.
7. Open Standard Codec
- The protocol itself is open, though the voice codec used (AMBE) is proprietary.
Cons of D-STAR:
1. Expensive Equipment
- Compared to DMR (which benefits from inexpensive commercial radios), D-STAR radios are typically more expensive and mainly produced by Icom and Kenwood.
2. Limited Manufacturer Support
- Unlike DMR or Fusion, which have multiple manufacturers, D-STAR is primarily supported by Icom, with some support from Kenwood. This limits the variety and price competition of radios.
3. Proprietary AMBE Codec
- While the D-STAR protocol is open, the AMBE codec is proprietary, meaning software developers must license it, limiting homebrew options.
4. Slower Data Rate
- D-STAR’s data transfer speed is relatively slow compared to modes like VARA, Packet, or even Fusion’s WiRES-X. This limits its usefulness for high-speed digital data applications.
5. Less Audio Clarity Than Some Competitors
- Some operators feel that DMR and Fusion provide better-sounding digital voice quality, though this is subjective.
6. Network Dependency for Global Communication
- While D-STAR works well for local simplex and repeater use, long-distance communication via reflectors requires an internet connection, making it dependent on network infrastructure.
7. More Complex Setup for New Users
- Programming a D-STAR radio requires understanding call sign routing, repeater linking, and reflectors, which can be intimidating for beginners compared to DMR or analog FM.
Conclusion:
D-STAR is a powerful and feature-rich digital mode that excels in call sign routing, GPS integration, and global linking. However, the limited manufacturer support, higher cost, and complexity of setup may make it less appealing compared to DMR or Fusion. If you already have D-STAR-compatible gear or enjoy experimenting with digital voice and data, it can be a great mode to explore.