Quick Answer
The HERE3+ uses a u-blox M8P receiver with single-band L1 GPS, GLONASS, and BeiDou support. It achieves roughly 2.5m accuracy in standard GPS mode and around 2.5cm with RTK. The HERE4 uses a u-blox NEO-F9P dual-band (L1/L5) receiver supporting all major constellations, and achieves sub-centimetre accuracy with RTK. The HERE3+ suits basic autonomous flight and entry-level precision work. The HERE4 is built for surveying, mapping, and applications demanding the highest positioning accuracy.
Understanding GNSS Accuracy Levels
Standard GPS gives roughly 2 to 5 metre accuracy. That works for waypoint navigation, return-to-home, and general autonomous flight. When you need centimetre-level precision for photogrammetry, surveying, or precision agriculture, RTK (Real-Time Kinematic) is required. RTK uses correction data from a fixed base station to eliminate satellite signal errors. Both the HERE3+ and HERE4 support RTK. The difference is in the receiver hardware, satellite bands tracked, and convergence speed. For more background, see our GPS modules for drones guide.
HERE3+ Overview
The HERE3+ uses the u-blox M8P receiver, tracking L1-band signals from GPS, GLONASS, and BeiDou. It connects to CubePilot autopilots via DroneCAN at 8Mbit/s, includes an ICM42688 IMU and RM3100 compass, weighs 51.8g, and measures 68mm square.
In standard GPS mode the HERE3+ achieves around 2.5m 3D accuracy. With RTK corrections from a base station, that drops to roughly 2.5cm. The update rate is 8Hz. It is a solid choice for autonomous survey missions where GPS hold and basic precision are sufficient.
HERE4 Overview
The HERE4 is a significant step up. It uses the u-blox NEO-F9P receiver tracking dual-band signals (L1 and L5) from GPS, GLONASS, Galileo, BeiDou, QZSS, and SBAS. Tracking two bands improves accuracy and reliability, particularly where satellite signals are partially obstructed.
The HERE4 achieves 0.01m (1cm) plus 1ppm accuracy with RTK. It converges to an RTK fix in under 10 seconds, much faster than the HERE3+. The navigation update rate reaches 20Hz in RTK mode. The HERE4 also has an STM32H757 dual-core processor, ICM42688 IMU, RM3100 compass, and MS5611 barometer.
Beyond positioning, the HERE4 can function as a secondary flight controller. With 8 PWM or BiDSHOT outputs, RC input, camera hotshoe, and trigger port, it is a self-contained solution for mapping drones needing precise positioning and camera synchronisation.
Specification Comparison
| Feature | HERE3+ | HERE4 |
|---|---|---|
| GNSS Receiver | u-blox M8P | u-blox NEO-F9P |
| Bands | Single-band (L1) | Dual-band (L1 + L5) |
| Constellations | GPS, GLONASS, BeiDou | GPS, GLONASS, Galileo, BeiDou, QZSS, SBAS |
| GPS Accuracy (3D Fix) | 2.5 m | N/A (RTK primary) |
| RTK Accuracy | 2.5 cm | 1 cm + 1 ppm |
| RTK Convergence | Variable | Under 10 seconds |
| Update Rate (RTK) | 8 Hz | Up to 20 Hz |
| Barometer | No | MS5611 |
| PWM Outputs | No | 8 (PWM or BiDSHOT) |
| Weight | 51.8 g | 60 g |
The Base Station
RTK requires a base station transmitting correction data. The Here4 Base is CubePilot's dedicated base station. It broadcasts corrections over radio to the HERE4 rover on the aircraft for real-time centimetre-level positioning. You can also configure a HERE4 module itself as a base in stationary mode, or use compatible base stations from Emlid and u-blox.
Which Module Should You Buy?
Choose the HERE3+ for autonomous flight, return-to-home, and basic waypoint missions. It handles entry-level RTK well enough for rough survey work and is more affordable for multi-aircraft operations.
Choose the HERE4 for photogrammetry, precision agriculture, surveying, or any application where every centimetre matters. Faster convergence, dual-band tracking, higher update rates, and the integrated camera trigger justify the higher cost. Its ability to serve as a secondary flight controller is a bonus for lightweight mapping rigs.
What to Buy
- CubePilot HERE3+ GNSS Module (M8P) — cost-effective GPS with basic RTK support
- CubePilot HERE4 Multiband RTK GNSS — dual-band precision for surveying and mapping
- Here4 Base Station — dedicated RTK base for centimetre-accurate corrections
- GPS & Navigation Systems — full range of GPS and GNSS modules
FAQ
Q: Do I need a base station for RTK to work?
A: Yes. RTK requires correction data from a base station with a known position. Without a base, both modules operate in standard GPS mode at metre-level accuracy.
Q: Can the HERE4 replace my flight controller entirely?
A: For simple mapping builds it can, thanks to its PWM outputs and RC input. Most operators use it alongside a Cube autopilot, with the HERE4 handling positioning and camera triggering while the Cube manages flight logic.
Q: Is the HERE4 compatible with Cube Orange+ and Cube Red Pro?
A: Yes. Both connect via DroneCAN. Plug the HERE4 into a CAN port on the carrier board, enable DroneCAN in your ArduPilot configuration, and it appears as a GPS and compass source.