Cubepilot Here4 Base RTK - without antenna

CubePilot Here 4 Base is a GNSS RTK base station that enhances the accuracy of drone navigation through RTK corrections transmission (RTCM). In combination with a compatible GPS module on the drone (rover), it can significantly improve position stability and achieve centimeter-level relative accuracy.

Here 4 Base is designed for easy use with a ground station, especially via Mission Planner or QGroundControl. To transmit corrections between the base and rover, a pair of telemetry modules is required to ensure a data link between the PC on the ground and the drone. On the ground side, the base connects to the computer via USB. The L1 + L5 antenna (not included) connects via an SMA connector.

The core of the module is the u-blox F9P chip, which supports BeiDou, Galileo, GLONASS, GPS, and QZSS systems. The GNSS module can receive up to 4 constellations simultaneously in L1 and L5 bands, contributing to faster fixes and better robustness of solutions in challenging environments. In RTK mode, the module specifies horizontal accuracy of 0.01 m + 1 ppm (CEP) and vertical accuracy of 0.01 m + 1 ppm (R50).

When used for the first time, the base is usually set up using the Survey-In method, where the desired accuracy and minimum measurement time are entered in Mission Planner. Achieving better absolute accuracy takes longer; in open space, it may take minutes for meters and tens of minutes to hours for tens of centimeters and less. This absolute accuracy of the base influences the absolute accuracy of the rover but does not limit relative accuracy between the base and rover, which can still be at the centimeter level even with a less accurate absolute position of the base.

Proper placement of the antenna and environment for RTK is very important. For a reliable fix, it is advisable to have as wide a view of the sky as possible, ideally with minimal obstacles above the horizon, and to avoid proximity to sources of interference. It is recommended to place it on a stable elevated platform, typically on a tripod, and to maintain a sufficient distance from obstacles and strong electrical devices.

Documentation