NMEA sentences include a talker identifier (aka “talker ID”) which is a two-character prefix identifying the GNSS.
Official GNSS talker IDs according to NMEA 4.11:
| Talker ID | GNSS | Owner | Coverage |
|---|---|---|---|
| GA | Galileo | European Union | Global |
| GB | BeiDou System (BDS) | People’s Republic of China | Global |
| GI | NavIC (formerly IRNSS) | Government of India | Regional - India |
| GL | GLONASS | Russian Federation | Global |
| GN | Global Navigation Satellite System (GNSS) | - | Global |
| GP | Global Positioning System (GPS) | U.S. Government | Global |
| GQ | QZSS | Government of Japan | Regional - Asia-Oceania |
Unofficial GNSS talker IDs, generated by receivers from various manufacturers:
| Talker ID | GNSS | Owner | Coverage |
|---|---|---|---|
| BD | BeiDou System (BDS) | People’s Republic of China | Global |
| GN * | GLONASS | Russian Federation | Global |
| IM | IMES | Government of Japan | Regional - Asia-Oceania |
| NC | NavIC (formerly IRNSS) | Government of India | Regional - India |
| QZ | QZSS | Government of Japan | Regional - Asia-Oceania |
Notes: