Unmanned Systems Technology 036

Trimble has developed two integrated smart antennas for high-precision GNSS navigation applications (writes Nick Flaherty). The AX940 and AX940i are designed for autonomous vehicles, precision agriculture and port automation. The antennas combine up to 336 frequencies from multiple satellite constellations from GPS, Galileo, GLONASS, BeiDou, QZSS and NavIC to provide more accurate positioning using Trimble’s Maxwell 7 GNSS receiver chipset. The accuracy, of down to 1-2 cm, comes without having to use a local base station or cell modem. Data from inertial sensors in the AX940i are combined with the GNSS data in a real-time kinematics (RTK) positioning and orientation engine, providing a continuous high-rate, low- latency output to guidance and control systems. The RTK system can be Trimble’s RTX network or OmniSTAR. The AX940 and AX940i provide RS- 232, USB, CAN and Ethernet interfaces to a system controller. The AX940i also includes wi-fi and Bluetooth connectivity for wireless interface and control. The 660 g smart antennas measure 221 x 218 x 52 mm and take a 9-30 VDC input via a 26-pin rugged connector. Power consumption is typically 3.0 W with two constellations. The smart antenna for GNSS navigation systems has an accuracy of 1-2 cm Precise GNSS antennas Navigation