Abstract

This article introduces the advantages of integrating the high-precision GNSS receiver Septentrio AsteRx-m3 pro with the open-source flight control system ArduPilot. This solution aims to address challenges faced by drones in complex electromagnetic environments, such as GNSS signal interference, spoofing, and the stability of precise positioning. Leveraging its military-grade AIM+ anti-jamming and anti-spoofing technology, centimeter-level RTK positioning accuracy, real-time dual-antenna heading capability, and support for all systems and frequencies, the AsteRx-m3 pro provides a reliable and precise navigation core for the flight control system. Its high update rate, low power consumption, and compact design enable seamless integration with ArduPilot. Ultimately, this combination significantly enhances the operational accuracy, system reliability, and autonomous capabilities of drones in professional scenarios such as inspection and surveying, providing robust support for building high-performance commercial drone systems.

High-Precision GPS/GNSS Positioning Technology Empowering Drone Flight Control Systems

In complex electromagnetic environments and demanding operational scenarios, the Septentrio AsteRx-m3 pro high-precision GNSS receiver, with its industrial-grade reliability and centimeter-level RTK positioning capability, provides a stable and trustworthy positioning and heading core for drone systems based on open-source flight controllers like ArduPilot/PX4. Utilizing its exceptional anti-jamming, anti-spoofing technology, and real-time dual-antenna heading capabilities, this device ensures that drones can achieve centimeter-level hovering and high-precision trajectory tracking during tasks like powerline inspection and precision surveying. Through seamless integration, it quickly endows the flight control system with fully autonomous operational capabilities, laying a solid foundation of spatio-temporal perception for the intelligent evolution of drones.

Challenges of GNSS in Drone Flight Control Systems

GNSS Positioning Integrity Failure Challenge

This refers to the flight control system’s inability to trust GNSS outputs at critical decision points. “Invisible” failure under spoofing attacks: Malicious GNSS signals can forge entirely plausible but false positioning, velocity, and time information. Without any warning, the flight control system might execute preset flight paths based on false positions, potentially causing the drone to collide with assets under inspection (e.g., hitting a transformer), deviate into unsafe areas where it could be captured, or perform “ghost hovering” over locations that are not actually safe.

“Visible” failure under complex interference: Broadband electromagnetic noise from high-voltage lines or substations can saturate the front-end of standard receivers, leading to complete loss of signal acquisition and tracking. The flight control system needs to quickly identify this and switch to alternative navigation sources (e.g., vision/LiDAR); otherwise, failsafe protocols will be triggered, potentially interrupting critical inspection missions.

Availability and Stability Challenges of RTK Positioning

During close-range precision operations, GNSS needs to provide continuous, high-precision pose solutions. Dynamic disturbances from multipath and signal occlusion: When drones maneuver between structures like transmission towers, pipelines, or buildings, satellite signals are strongly reflected by metal, causing rapidly changing multipath errors that can lead to positioning “jumps” of tens of centimeters. Such jumps are fatal for operations requiring centimeter-level stability, such as automatic hovering or precise path following.

The fragility of RTK/PPK high-precision solutions: While carrier-phase differential technology provides centimeter-level accuracy, its initialization time and ability to maintain fixed solutions severely degrade in complex electromagnetic environments and near structures. Excessive baseline length (relative distance to the base station) or loss of lock due to interference directly causes the flight controller to lose high-precision positioning input.

GNSS Signal Quality and Fusion Challenges in Dynamic Environments

GNSS is the core of multi-sensor fusion navigation for drones, and its quality fluctuations directly impact overall state estimation.

Electromagnetic pulses and transient interference: Transient strong electromagnetic pulses generated by switching arcs or discharges can cause short-term “blinding” or output jumps in the GNSS receiver. The flight controller’s fusion filter (e.g., Kalman filter) must be able to detect and isolate these outliers to prevent erroneous states from corrupting the entire navigation solution.

Intelligent switching in heterogeneous signal environments: Rapid environmental changes during inspections (e.g., flying from open space near high-voltage lines) require the flight controller to dynamically assess GNSS confidence and smoothly switch between modes dominated by GNSS, vision, inertial navigation, etc. Any delay or jitter in switching can cause abrupt changes in control commands, leading to hazards.

Core Advantages of the Septentrio AsteRx-m3 pro

Top-Tier Anti-Jamming and Anti-Spoofing Capabilities – AIM+ Technology

AIM+ (Advanced Interference Mitigation) is an industry-leading anti-jamming and anti-spoofing technology featuring unique hardware filtering and adaptive digital filtering capabilities.

Effectively counters various interference sources, including pulsed interference, broadband swept-frequency interference, narrowband interference, pseudolite interference, etc.

Built-in RF spectrum monitoring system detects and locates interference sources in real-time, ensuring high-precision positioning is maintained even in high-interference environments.

In real-world jamming and spoofing tests organized by the Norwegian government, the AsteRx-m3 pro Pro performed excellently, maintaining 99.5% positioning availability under strong interference, outperforming most competitors.

Full Constellation, Full Frequency Support and High-Precision RTK Performance

Supports signals from multiple systems and frequencies including GPS, GLONASS, BeiDou, Galileo, QZSS, NavIC, and SBAS.

-Provides reliable centimeter-level RTK positioning accuracy (horizontal: 0.6 cm + 0.5 ppm, vertical: 1 cm + 1 ppm).

-Supports dual-antenna mode, providing high-precision heading and pitch/roll angle information without relying on magnetic sensors or vehicle dynamics.

Ultra-Low Power Consumption and Compact Design (Optimal SWaP)

-Lowest power consumption in its class, operating at only 1000 mW in full constellation, all-frequency mode.

-Dimensions: only 47.5 × 70 × 9.32 mm, weight: 27 g, suitable for embedded applications with strict size, weight, and power (SWaP) requirements.

GNSS+ Algorithm Suite Ensures Stability in Complex Environments

-LOCK+: Maintains stable tracking under high vibration and shock.

-IONO+: Mitigates the impact of ionospheric scintillation on signals.

-APME+: Effectively suppresses multipath effects, improving observation quality.

-RAIM+: Receiver Autonomous Integrity Monitoring enhances system reliability.

Easy Integration and Operation

-Provides complete interface documentation, command sets, SDK, and RxTools configuration software.

-Supports Web UI for remote configuration and status monitoring, suitable for unmanned and remote deployments.

-Compatible with multiple data formats (SBF, NMEA, RTCM, CMR) and communication interfaces (serial, USB, Ethernet, NTRIP).

Integration Advantages of Septentrio AsteRx-m3 pro with ArduPilot

RTK Positioning and Attitude Output Enhance Flight Control Precision

The AsteRx-m3 pro supports centimeter-level RTK positioning (horizontal: 0.6 cm + 0.5 ppm) and dual-antenna heading/attitude output (heading accuracy up to 0.03°, pitch/roll accuracy 0.05°).

ArduPilot can directly use its high-precision position, velocity, and heading information to achieve more stable hovering, precise route tracking, automated takeoff/landing, etc., making it particularly suitable for tasks like drone surveying, precision spraying, and formation flying.

Powerful Anti-Jamming Capabilities Enhance System Reliability

Integrated AIM+ anti-jamming and anti-spoofing technology effectively suppresses swept-frequency interference, pulsed interference, spoofing signals, etc., ensuring stable positioning data output even in complex electromagnetic environments.

For drones flying in urban areas, airports, industrial zones, and other scenarios with numerous potential interference sources, this system can significantly reduce the risk of loss of control due to GNSS signal loss or jumps.

High Update Rate and Low Latency, Suitable for High-Dynamic Flight

Supports a 100 Hz position update rate and < 20 ns event marker accuracy, providing ArduPilot with high-frequency, low-latency positioning input.

Applicable to high-speed drones, autonomous obstacle avoidance, agile maneuvering, and other applications requiring fast position feedback, improving system responsiveness and control quality.

Full Constellation, Full Frequency GNSS Support Improves Satellite Availability

Supports all major constellations and frequencies (GPS, GLONASS, BeiDou, Galileo, QZSS, NavIC, SBAS), significantly increasing the number of visible satellites.

Maintains higher positioning availability in occluded environments (e.g., urban canyons, forests), reducing the likelihood of ArduPilot degrading positioning modes due to insufficient satellite count.

Supports PPK and Post-Processing, Improving Survey Data Quality

Provides SDK and post-processing libraries supporting PPK (Post-Processed Kinematic) mode.

Can be combined with ArduPilot’s logging system to provide higher-precision trajectory data for aerial survey and 3D modeling tasks, enhancing final map/model accuracy.

AsteRx-m3 pro + ArduPilot: Building Professional-Grade Autonomous Systems

Injecting Industrial-Grade High-Precision GNSS Core Capabilities into ArduPilot

With its centimeter-level RTK positioning and sub-degree heading accuracy, combined with its unique AIM+ military-grade anti-jamming technology, the AsteRx-m3 pro elevates ArduPilot’s navigation performance to a professional operational level, ensuring the system maintains high mission success rates and reliability even in harsh environments from polar regions to deserts.

Reducing Development Costs

Thanks to its ultra-compact size and plug-and-play interface design, the AsteRx-m3 pro can be easily deployed alongside ArduPilot flight controller boards in space-constrained platforms. Its complete development toolchain allows developers to quickly build high-performance systems based on mature solutions, significantly lowering integration difficulty and overall development costs.

Multiple Performance Advantages Enhance Overall System Value

The system integrates performance advantages like 100 Hz high-frequency updates, full constellation/frequency tracking, dual-antenna heading output, and PPK post-processing. This not only meets the needs of high-dynamic and precise control but also greatly improves usability in complex environments and post-processing data accuracy, providing solid support for diverse commercial applications.

Future-Proof Technology Investment and Scalability of the AsteRx-m3 pro

The AsteRx-m3 pro supports next-generation security services like OSNMA and features over-the-air firmware upgrade capability, ensuring your system can evolve continuously to adapt to future technological developments in autonomous navigation and precise positioning. Its low power consumption and network-compatible design also lay a solid foundation for long-term operation and scalability.

ArduPilot Professional-Grade Reliability Ensures Commercial Deployment

With MIL-STD-810G vibration certification, RAIM+ autonomous integrity monitoring, and an MTBF exceeding 50,000 hours, the AsteRx-m3 pro provides industrial-grade reliability assurance for the ArduPilot system, ensuring it can stably support 24/7 continuous operation for critical commercial missions.

Typical Return on Investment Scenarios for ArduPilot

In scenarios such as precision agriculture, infrastructure inspection, logistics delivery, and scientific research and development, this combined solution can achieve rapid return on investment by improving operational accuracy, ensuring mission reliability, and optimizing operational efficiency, helping users translate technological investment into measurable business value.

Conclusion

The combination of AsteRx-m3 pro and ArduPilot provides a high-performance, easily integrable, and future-proof solution for building professional-grade autonomous systems. It not only significantly enhances the capability ceiling of the open-source flight control platform but also, with its industrial-grade reliability and powerful anti-jamming capabilities, ensures the system can create sustained value in demanding commercial applications.

What fundamental changes does integrating the Septentrio AsteRx-m3 pro bring to the ArduPilot drone system compared to traditional GNSS modules?

This integration elevates the navigation capability of the ArduPilot system from “usable” to a professional level of “trustworthy and precise.” The fundamental changes are: through military-grade AIM+ anti-jamming and anti-spoofing technology, it enables drones to maintain high reliability in strong electromagnetic interference environments like near high-voltage lines and substations, avoiding the risk of loss of control due to signal loss or spoofing; simultaneously, with centimeter-level RTK positioning and 0.03°-precision dual-antenna heading, it provides the flight controller with unprecedentedly accurate pose data, directly enabling centimeter-level hovering, high-precision route tracking, and other precision operations, addressing the pain points of accuracy jumps and loss of lock experienced by traditional solutions in complex environments.

In professional drone applications like inspection and surveying, how does the AsteRx-m3 pro specifically address the issues of “multipath interference” and “instantaneous signal occlusion” faced by GNSS signals?

The AsteRx-m3 pro provides targeted optimization for these issues through its GNSS+ advanced algorithm suite. Its APME+ algorithm effectively suppresses multipath effects caused by reflections from metal structures, reducing positioning “jumps”; the LOCK+ technology ensures satellite tracking is maintained during high-dynamic vibrations and instantaneous signal interruptions, shortening reacquisition time; and its full constellation, full frequency support significantly increases the number of visible satellites, maintaining sufficient satellite geometry even in partially occluded environments like near buildings or towers. This ensures the continuity and stability of RTK fixed solutions, guaranteeing the coherence and safety of precision operations.

Besides high-precision positioning, what other advanced application scenarios or system optimizations does the integration of AsteRx-m3 pro and ArduPilot enable?

This combination unlocks potential for several advanced applications and system optimizations. Its high update rate (100Hz) and low latency make it suitable for scenarios with extreme real-time requirements, such as high-speed drones and autonomous obstacle avoidance. The high-precision attitude angles from the dual-antenna output can replace or serve as a redundant source for the magnetometer, providing reliable heading in magnetically disturbed environments. Complete support for PPK post-processing, combined with flight logs, can provide centimeter-level post-mission trajectories for aerial survey modeling, improving the absolute accuracy of final maps/models. Its industrial-grade reliability (MIL-STD-810G certification, long MTBF) and remote monitoring capabilities further lay a solid foundation for achieving scalability and unmanned operations.