Performance; Interfaces - Garmin GPS 25 LP Technical Specification

1.4.4

Performance

1) Tracks up to 12 satellites (up to 11 with PPS active)
2) Update rate: 1 second
3) Acquisition time
- 15 seconds warm (all data known)
- 45 seconds cold (initial position, time and almanac known, ephemeris unknown)
- 1.5 minutes AutoLocate
- 5 minutes search the sky (no data known)
4) Position accuracy:
Differential GPS (DGPS): Less than 5 meters RMS
Non-differential GPS: 15 meters RMS (100 meters with Selective Availability on)
5) Velocity accuracy: 0.2 m/s RMS steady state (subject to Selective Availability)
6) Dynamics: 999 knots velocity, 6g dynamics
7) One-pulse-per-second accuracy: ±1 microsecond at rising edge of PPS pulse
(subject to Selective Availability)
1.4.5

Interfaces

1) Dual channel CMOS/TTL level (-xVC versions) or RS-232 compatible level (-xVS
versions), with user selectable baud rate (300, 600,1200, 2400, 4800, 9600,
19200)
2) NMEA 0183 Version 2.0 ASCII output (GPALM, GPGGA, GPGSA, GPGSV,
GPRMC, GPVTG, PGRME, PGRMT, PGRMV, PGRMF, LCGLL, LCVTG)
Inputs
- Initial position, date and time (not required)
- Earth datum and differential mode configuration command, PPS Enable,
almanac
Outputs
- Position, velocity and time
- Receiver and satellite status
- Differential Reference Station ID and RTCM Data age
- Geometry and error estimates
3) Real-time Differential Correction input (RTCM SC-104 message types 1,2,3 and 9)
4) One-pulse-per-second timing output
5) Optional binary TTL output data format
6) Binary Format Phase Data
(almanac known, initial position and time unknown)
TM
4