GPS PROCESSING
- Standard NMEA 2.0 GGA and RMC sentences
- Utilizes SIRF3 based receiver
- Typical accuracy within 15 meters
DATA MODEM INTERFACE
- FFSK/MSK data communication over existing voice channel
- 1200 bits-per-second data rate
- FEC, CRC, interleaving and data scrambling used
- Messages include 8 character unit ID
POLL-BASED POSITION REPORTING
GPSMIC always responds from the Base Station (or optionally, a base-configured GPSMIC)
AUTOMATIC POSITION REPORTING MODES
1. Push-To-Talk (PTT) switch activated
- Position report sent either on every PTT or a time-throttled basis
2. Fixed-Time Based
- Periodic reporting of position
- Time interval value: 1 - 255
- Time interval units: seconds, minutes, hours, or days
3. Fixed-Distance Based
- Position reported if location change exceeds set distance threshold
- Distance Threshold : 100 meters – 64 Km
- Operational modes: absolute (e.g. geo-fence) or relative (between successive location reads
- Uses separate periodic time check which may be set by user
