Ruggedized dual antenna GNSS receiver

  • 544 channels for tracking all known and future signals from GPS, GLONASS, GALILEO, BEIDOU, NavIC, QZSS & SBAS on both antennas
  • Precise and solid heading calculation
  • centimetre-level (RTK) and dm-level (PPP) position accuracy
  • Compatible with RTK and SBAS corrections
  • Septentrio GNSS+ algorithms for solid performance even in regions of evaluated ionospheric activity
  • Integrated cellular modem, Bluetooth and WiFi; optional UHF radio

Note: product with limited availability.

Orders accepted until, and not later than February 29, 2024 (last time buy date, subject to availability) for configurations including North America 4G cell modem.

Orders accepted until, and not later than July 31, 2023 (last time buy date, subject to availability) for all other configurations.

Built around Septentrio’s latest ASIC, the GReCo4, it features built-in jamming detection and countermeasures, multi-path rejection and fast acquisition. It is accurate and reliable now and into the future with over 500 channels to track all available constellations (GPS, GLONASS, Galileo, BeiDou, NavIC and QZSS) and has many of Septentrio’s special GNSS+ algorithms (see further below).

Compact and portable, the AsteRx-U was developed with machine control users in the agricultural, construction and mining industries in mind. With the help of RTK, users can benefit from centimeter positioning accuracy. 

The receiver is configurable from any device from a web browser and there is no longer need for additional equipment such as spectrum analyzer, modem and UHF radio because Septentrio has developed all these features into the AsteRx-U.

The GNSS+ toolkit - converting bad environments into good positioning

Activity in the ionosphere is a problem for GNSS signals, from loss of RTK fix to total loss of signal lock. Having honed our skills, supporting applications in the most iono-active areas on Earth,  the result is IONO+: the most advanced protection against ionospheric disturbances to GNSS signals on any receiver.

Metal and large nearby structures can reflect GNSS signals and produce multipath. The Advanced Multipath Mitigation Technology (APME+) system effectively disentangles direct and reflected signals enhancing both position and measurement quality. APME+ is bias free and, in line with Septentrio’s commitment to maximum configurability, can be disabled.

Advanced Receiver Autonomous Integrity Monitoring (RAIM+comprises fault detection mechanisms of the receiver at all the levels including the generation of measurements, quality control and navigation algorithms. Detected faulty measurements, which are typically caused by high multipath or active ionosphere, are removed from the solution.

Mechanical vibrations or shocks caused by rough terrain can wreak havoc with satellite tracking. LOCK+ automatically adjusts the parameters of the AsteRx4 high-precision GNSS receiver so you never lose position.

AIM+ anti-jamming and RF spectrum monitoring system

All Septentrio high-precision GPS/GNSS receivers feature AIM+, the most advanced onboard radio frequency interference (RFI) monitoring and mitigation technology on the market. It can suppress the widest variety of interferers, from simple continuous narrowband signals to the most complex wideband and pulsed jammers. The built-in protection against intentional and unintentional jamming and spoofing uses a sophisticated system of sampling and mitigation mechanisms. The RF spectrum can be viewed in real-time in both time and frequency domains.

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.

Illustrative image for Septentrio AsteRx-U3 GNSS Receiver Web User Interface (WebUI)

Septentrio’s 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
RTK (base and rover)
More info

Optional feature

Heading GNSS attitude
More info

Optional feature


Hi-speed serial ports (RS232)
Ethernet port (TCP/IP, UDP, LAN 10/100 Mbps)
High-speed/full-speed USB device port
Event markers
More info

Depending on configuration.

xPPS output (max. 100 Hz)
Integrated bluetooth (2.1 + EDR/4.0)
EU 4G LTE model
More info

4G compatibility in Europe and other regions: 4G LTE CAT4 (B1, B3, B5, B7, B8, B20), 3G UMTS/HSDPA/HSUPA (850/900/1900/2100), 2G GSM/GPRS/EDGE (850/900/1800/1900)

NA 4G LTE model
More info

4G compatibility in North America and other regions: 4G LTE CAT4 (B2, B4, B5, B7, B17), 3G UMTS/HSDPA/HSUPA (850/900/AWS1700/1900/2100), 2G GSM/GPRS/EDGE (850/900/1800/1900)

Integrated WiFi (802.11 b/g/n)
Integrated UHF (406-470 MHz)
More info

Optional feature

Integrated position accuracy

Standalone - horizontal
More info

Open-sky conditions. RMS levels.

1.2 m
Standalone - vertical
1.9 m
SBAS - horizontal
0.6 m
SBAS - vertical
0.8 m
DGNSS - horizontal
0.4 m
DGNSS - vertical
0.7 m


Horizontal accuracy
More info

+ 0.5 ppm

0.6 cm
Vertical accuracy
More info

+ 1 ppm

1 cm


Velocity accuracy
More info

Open sky conditions. RMS levels.

3 cm/s

Product datasheet

Support documentation

Important notes - Firmware upgrade:

  • Only AsteRx-U products with an internal random-access memory (RAM) larger than 64 MB are eligible for an upgrade to version 4.10.4. This means that AsteRx-U UHF with a serial number lower than 360231 and AsteRx-U, AsteRx-U MARINE with a serial number lower than 3402295 cannot run this version and needs to remain at firmware version
  • This firmware version does not support Septentrio SECORX positioning based on TerraStar service. Receivers actively using the SECORX service need to remain at firmware version 4.5.3


End of life notification AsteRx-U and AsteRx-U Marine
153.97 KB
AsteRx-U/AsteRx-U UHF/AsteRx-U MARINE User Manual v1.14
7.76 MB
AsteRx-U Quick Start Guide
647.73 KB
AsteRx-U Firmware Package v4.5.3
44.4 MB
AsteRx-U Firmware Package v4.5.0.1
42.61 MB
141.19 KB
3D drawing
4.19 MB

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