Holybro H-RTK Unicore UM982 Dual Antenna Heading GNSS

The Holybro H-RTK UM982 is a dual-antenna RTK GNSS receiver built on the Unicore UM982 module. Besides centimetre-level RTK positioning, it measures the vehicle's heading from its two antennas (moving-baseline yaw), giving PX4 and ArduPilot vehicles a yaw source that motors, power wiring and metal structures cannot disturb. It suits survey, mapping, inspection and autonomous platforms that operate near magnetic interference.

Key features

• GPS heading works even without RTCM corrections from a base station or NTRIP service

• Multi-band tracking across GPS, GLONASS, BeiDou, Galileo and QZSS

• 20 Hz positioning, heading and raw observation output

• Onboard IST8310 magnetometer, status LED and safety switch

• Also works as an RTK-corrected rover without heading, or as a manually configured base station sending RTCM to the ground station

Specifications

• GNSS module: Unicore UM982

• Signals: GPS L1C/A, L2P(Y), L2C, L5; GLONASS L1, L2; BeiDou B1I, B2I, B3I; Galileo E1, E5a, E5b; QZSS L1, L2, L5

• Heading accuracy: 0.1° (1 m antenna baseline)

• Update rate: 20 Hz

• Time to first fix: 30 s or less cold, 5 s or less hot

• Compass: IST8310

• Ports: JST-GH 10-pin, JST-GH 6-pin (UART2), USB-C

• Default baud rate: 230400

• Antenna connector: SMA (female on the board)

• Antenna gain: 2.5 dBi peak, 33 dB LNA (typical)

• Supply: 4.75-5.25 V, about 350 mA

• Board size: 34.8 x 58.9 x 14.4 mm

• Weight: 40.3 g without antennas

Mount both antennas rigidly with a clear view of the sky and enter their offsets in the autopilot; wider spacing gives better heading accuracy. The status LED needs PX4 1.14 or ArduPilot 4.4.0 and later.