Septentrio-powered GNSS receivers for ArduPilot (GPS_TYPE 9) — anti-jamming RTK, dual-antenna heading

Hi all — we’re **UAV GNSS** (uav-gnss.com), building ready-to-use receivers around **Septentrio mosaic modules**. Since many ArduPilot users run Septentrio receivers (fully supported as GPS_TYPE 9), I wanted to share a practical setup guide and the anti-jamming angle, in case it’s useful.

**Quick setup (Pixhawk + Septentrio)**

- Wire Septentrio COM2 TX/RX to the Pixhawk GPS1 port (5V/GND)

- Set baud rate 115200 on both sides

- Parameters: GPS_TYPE=9 (Septentrio), GPS_BAUD_RATE=9 (115200), GPS_RATE_MS=100

- Verify 3D fix with >16 satellites

**Why anti-jamming matters for drones**

GNSS signals arrive at roughly 20 W light-bulb power from 20,000 km. Near 4G/5G towers, power lines, or co-located radios, a standard receiver loses RTK fix or drifts to meter level. Septentrio’s AIM+ gives roughly 60 dB of interference mitigation vs ~25 dB typical of consumer modules — the difference between holding centimeter-level RTK or losing it mid-flight.

**Dual-antenna heading**

The mosaic-X5 P3H / mosaic-G5 P3H variants give dual-antenna heading and pitch/roll over the same GPS serial port — no separate IMU/compass needed, which some builders like for redundancy or payloads where a magnetometer is unreliable.

**Integration guide (open source)**

We published a full wiring + parameter guide with an SBF parser script on GitHub: GitHub - uavgnss6-bot/septentrio-gnss-integration-guide: Septentrio GNSS receiver integration guide for ArduPilot and PX4 — wiring, configuration, RTK setup, and SBF data parsing. · GitHub . Receiver lineup: UAV GNSS Receivers for Drone Mapping & Survey | Septentrio mosaic-G5 and X5

Happy to answer technical questions here. If anyone else runs Septentrio with ArduPilot, curious what your experience has been.