AsteRx-U3 Marine

Multi-constellation, dual-antenna GNSS receiver for marine applications

  • Full-constellation, triple-frequency satellite tracking on both antennas
  • Sub-degree GNSS heading & pitch or heading & roll
  • Centimeter-level (RTK) performance and sub decimeter-level (PPP) position accuracy  
  • L-band reception, robust against Iridium and Inmarsat uplink interference 
  • Support for FUGRO Marinestar corrections 
  • AIM+ unique interference mitigation system as part of the advanced GNSS+ algorithm suite
  • Integrated UHF radio, cellular modem, Bluetooth and Wi-Fi

The AsteRx-U3 MARINE is designed for marine survey and construction users. It is a multi-frequency GNSS receiver offering precise GNSS positioning and heading with enhanced Iridium and Inmarsat uplink interference mitigation. 

Consistently accurate now and into the future

The AsteRx-U3 is the most advanced integrated multi-constellation dual-antenna receiver from Septentrio. Its multi-frequency engine can track signals from all Global Navigation Satellite System (GNSS) constellations: GPS, GLONASS, Galileo, BeiDou, NavIC and QZSS – on both antennas. This guarantees you reliable and accurate GNSS positioning now and into the future.

Reliable centimeter accuracy

Septentrio’s 20 years of experience in the GNSS industry ensures that the AsteRx-U3 offers the highest possible accuracy, down to the centimeter level. LOCK+ technology maintains tracking during heavy vibrations and IONO+ ensures position accuracy even during periods of elevated ionospheric activity. The AsteRx-U3 offers the very latest in advanced interference mitigation technology  AIM+, which filters out ambient intentional and unintentional RF interference.

Any device, any platform

Use any device with a web browser to operate the AsteRx-U3 without any special configuration software via the Web interface, accessible over Ethernet, Wi-Fi or USB connections.

AIM+ anti-jamming and RF spectrum monitoring system

AIM+ offers built-in protection against intentional and unintentional jamming using a sophisticated system of sampling and mitigation mechanisms. Your high-precision GNSS receiver can automatically suppress the widest variety of interferers from simple continuous narrow-band signals to the more complex wide band and pulsed transmitters as well as lnmarsat and Iridium satellite transmissions.  

Intuitive web user interface

With your high-precision GPS reference receiver comes an intuitive web user interface for easy operation and monitoring allowing you to control the receiver from any mobile device or computer. The web interface also uses easy-to-read quality indicators ideal to monitor the receiver operation during the job at hand.


GNSS technology

GPS: L1 C/A, L1C, L2C, L2 P(Y), L5
Beidou: B1I, B1C, B2a, B2I, B2b, B3I
Galileo: E1, E5a, E5b, E5 AltBoc
QZSS: L1 C/A, L1C/B, L2C, L5
NavIC: L5
5 constellation RTK (base and rover)

Septentrio patented GNSS+ technologies

AIM+ Advanced Interference Monitoring and Mitigation
More info


Unique anti-interference system monitors, flags and mitigates narrow and wideband interference, jamming and spoofing.

More info


Hi-speed serial ports (RS232)
Ethernet port (TCP/IP, UDP, LAN 10/100 Mbps)
xPPS output (max 100Hz)
Outputs to drive external LEDs
General purpose output
NTRIP (client)
Initialisation time
7 s
Bluetooth (2.1 + EDR/4.0)
WiFi (802.11 b/g/n)
UHF (410-475 MHz)
Cellular modem: LTE CAT4

Other positioning modes accuracy

Horizontal DGNSS
0.4 m
Vertical DGNSS
0.7 m


Velocity accuracy
3 cm/s

Maximum update rate

10 Hz
Measurements only
10 Hz


More info



Time precision

xPPS out
More info

Incl. software compensation of sawtooth effect


Product datasheet

Support documentation

AsteRx-U3 MARINE User Manual v1.3
11.22 MB

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