TraceAssist Ephemeris keeps rovers ahead of the broadcast ephemeris cycle. While a receiver is still acquiring satellites, TraceNav repeats the latest orbital parameters so positioning engines can start computing immediately.
Why it matters
- Faster first solution: No need to wait for satellites to send their own ephemeris pages (which can take minutes).
- Reliable cold starts: Essential for rovers that power-cycle or move between job sites frequently.
- Unified delivery: Uses the same NTRIP connection as the main correction stream—no additional sockets or SDKs required.
Broadcast behavior
If your rover supports assisted positioning metadata, configure it to store the latest ephemerides. This avoids re-requesting data after short drops.
Typical startup timeline
Rover responsibilities
- Parse & cache: Store incoming ephemerides until a fix is achieved; most SDKs do this automatically.
- Send GGA: Transmit NMEA GGA sentences every 1–5 seconds once position estimates become available.
- Validate fallbacks: If GGA stops, TraceRouter can resume ephemeris mode (depending on configuration).
Monitoring
Within the TraceNav dashboard:
- Open the device session detail to view Ephemeris Mode duration.
- Verify message counts—ephemeris bursts appear as spikes in message 1019/1020/1042/1046 graphs.
