FURUNO, GS-100 SATELLITE SPEED LOG

The GS-100 works using GNSS satellites:

Receives signals from multiple satellite systems (GPS, GLONASS, Galileo)
Calculates:
- Ship position
- Speed over ground (SOG)
- Heading and motion
Uses an integrated satellite compass to determine direction and movement

The Furuno GS-100 is a GNSS-based (satellite) speed log used on ships to measure speed, distance, and vessel motion with very high accuracy—especially at low speeds during berthing and docking.

Technical Specification

📡 General

Type: GNSS Satellite Speed Log (SDME + THD compliant)
Principle: Multi-GNSS (GPS / GLONASS / Galileo / QZSS)
Standards:
- IEC 61023 (SDME)
- ISO 22090-3 (THD)

🚢 Measurement performance

Speed range

Longitudinal (fore–aft):
-60.0 to +60.0 knots
Transverse (port–starboard):
-60.0 to +60.0 knots

Accuracy

High accuracy (≥5 satellites):
- ±0.02 kn RMS (at antenna)
- ±0.08 kn RMS (at reference position)
Low satellite condition (3–4 satellites):
- ±2% or ±0.2 kn

Distance measurement

Trip distance:
0.00 to 999,999.99 nautical miles
Distance resolution:
0.01 NM

Heading & motion

Heading range: 0° to 359.99°
Heading / Roll / Pitch accuracy: ~0.4–0.5° RMS
Rate of Turn (ROT):
0.1°/min or 0.01°/min (selectable)

Response performance

Following speed: 45°/s
Settling time: ~90 seconds
Heading backup: ≤1° (short signal loss)

📡 GNSS antenna unit

Receiving frequency:
- GPS/Galileo/QZSS: 1575.42 MHz (L1)
- GLONASS: 1602.56 MHz
Tracking channels:
- GPS: 12
- GLONASS: 10
- Galileo: 8
- QZSS: 2
Position accuracy:
- GNSS: ~5 m (2drms)
- SBAS: ~4 m