• SAAB R4 GPS System

SAAB R4 GPS System

IMO require SOLAS class ships to carry type approved GPS equipment. Saab
TransponderTech can offer a number of IMO-compliant GPS and DGPS solutions,
either as stand-alone Navigation Systems or as a additions to existing Saab AIS

The navigation products from Saab are self-monitoring and extremely user friendly. They perform
continuous RAIM (Receiver Autonomous Integrity Monitoring) calculations. This allows the Officer Of
the Watch (OOW) to set the required navigation accuracy for any stage of the journey. The R4 Navigation
System from Saab will give continuous feedback and alarm if the accuracy limit is exceeded.
R4 GPS Navigation Sensor The R4 GPS Navigation Sensor is a high-precision
GPS receiver, capable of receiving SBAS (e.g. WAAS and EGNOS) differential corrections. The unit
performs continuous RAIM calculations, which enhance the integrity of the position data.

The R4 Control and Display Unit performs a multitude of navigation functions. The traffic light LEDs
are used to continuously indicate the status of the RAIM calculations. Green light tells the OOW that
the position accuracy is within the required value. In combined DGPS/AIS confi gurations, the R4
Control and Display Unit will display and control Navigation data, in addition to the AIS information.
Saab’s R4 GPS/DGPS products will of course be ideal to connect to existing or future AIS systems,
ensuring that the ship operates in full compliance with all relevant regulations. GPS information is
becoming extremely vital for many systems onboard and hence critical to overall safety.


Waypoints 2000 waypoint memory
Routes 100 routes, using a total of 2000
Functions Navigation (rhumb line and great circle),
Position, Route, Waypoint,
Event Mark, Plot, Sail To, MOB,
GPS/DGPS, Alarms, Time Alerts,
Trip Logs, Anchor Watch Alarm,
Confi guration
Integrity The product performs RAIM
calculations in accordance with IEC
61108-1 Ed. 2
Supply 22 - 30 V DC, 12.5 W
Display High Resolution 6 inch,
¼ VGA monochrome, Sunlight Readable
LEDs 1 Power and 3 RAIM status (R/Y/G)
Yoke or fl ush mounting of Display Unit

GPS Receiver
L1, C/A-code with carrier phase smoothing
12 channels (2 channels dedicated to SBAS)
DGPS by SBAS or externally input RTCM corrections
Update rate 1 Hz default, 5 Hz max
Position accuarancy GPS*: 5 m, DGPS** 1 m
(2D RMS)
Cold start 1 min typical

DGPS Beacon Receiver
Dual receiver: Manual or Automatic tuning
Frequency 283.5 to 325.0 kHz
MSK Bit Rates 50, 100, and 200 bps
Cold Start Time <1 minute typical
Reacquisition <2 seconds typical
Sensitivity 25 μV/m for 6 dB SNR @ 200 bps

2 bi-directional user ports RS422
1 output port RS422
Ports are confi gurable 4,800 - 38,400 bps
Alarm output for relay activiation
Alarm acknowledge input discrete
Log pulse output

Dimensions (WxHxD)
Control and Display unit 270 x 207 x 102 mm
Navigation Sensor 128 x 39 x 137 mm

Control and Display unit 1.1 kg (2.4 Ib)
Navigation Sensor 0.5 kg (1Ib)

Power/Data Cable to Navigation Sensor
2 m (7 ft). 18 pin MaxiCon - pigtail
Data Cable to Control and Display Unit
2 m (7 ft). 18 pin MaxiCon - pigtail
Power Cable to Control and Display Unit
2 m (7 ft). 3 pin MaxiCon - pigtail
GPS Antenna Cable (recommended)
RG214 and RG213: Max length 45 m
TNC connector

NMEA Messages

Proprietary Messages
For RAIM control and display
Environmental data
Protected environment (IEC 60945)
Operating temerature -15 °C to +55 °C
Compliance with the pollowing Standards
IMO Performance Standard for GPS
IEC 61108-1 Ed2, GPS
IEC 61162-1/2 Ed.2, NMEA 0183, version 2.0
through 3.0
* Dependent upon ionospheric activity and multipath
** SVs >5, HDOP <2, RTCM SC-104 correction data from
a dual frequency reference station, short baseline,
and low multipatch environment
Type approvals

SAAB R4 GPS System