
CHCNAV, a leading provider of high-precision GNSS solutions, is at the forefront of transforming positioning and navigation capabilities for unmanned systems.
As industries like drone mapping, autonomous navigation, and precision agriculture increasingly demand higher accuracy, various correction methods have emerged to enhance GNSS performance. This comprehensive guide from CHCNAV explores the main correction techniques available today and their applications in unmanned systems, highlighting how these technologies enable precise positioning across diverse operational environments.
Real-Time Kinematic (RTK)
Real-Time Kinematic (RTK) positioning represents a significant advancement over standard GNSS techniques. While standard positioning provides meter-level accuracy, RTK achieves centimeter-level precision through sophisticated carrier-phase measurements and real-time error correction.
Single Base RTK
Single Base RTK remains one of the most widely adopted correction methods in the industry. CHCNAV’s iBase station exemplifies the modern approach to RTK implementation, offering a compact and portable solution that’s ideal for unmanned system operations. The system employs a base station positioned at a known fixed location, which works in conjunction with a rover receiver mounted on the unmanned platform. Real-time correction data flows continuously between these two components, enabling precise positioning.
The advantages for unmanned systems are substantial. Users can achieve centimeter to millimeter-level accuracy, making it suitable for precise navigation and mapping tasks. The flexible deployment options allow operators to quickly set up and relocate the base station as needed, while the one-time investment structure eliminates recurring subscription fees. This method proves particularly effective for controlled operation areas where consistent accuracy is crucial for mission success.
Network RTK
Network RTK builds upon traditional RTK by utilizing multiple permanent base stations to cover large areas. This networked approach is particularly valuable for autonomous vehicle operations and large-scale drone mapping projects where consistent accuracy across extensive areas is crucial.
The system provides seamless coverage across wide areas, eliminating the need for operators to reset and reconnect to new base stations as they move through different regions. This continuous connectivity makes it an ideal solution for autonomous navigation in urban environments, where reliable positioning is essential for safe operation. The network approach ensures consistent accuracy over large regions, maintaining centimeter-level precision regardless of the operation’s scale.
PPP and PPP-RTK

A John Deere Tractor with CHCNAV NX510SE Auto Steering System.
Precise Point Positioning (PPP) and its RTK variant offer unique advantages for unmanned systems operating in remote areas. These methods leverage satellite-delivered corrections, making them particularly valuable for long-range drone operations that venture beyond the reach of conventional RTK networks. Maritime autonomous systems benefit from the global coverage, while remote area surveying operations can maintain precise positioning without local infrastructure. The technology proves especially useful for operations in areas with poor cellular coverage, where traditional network-based solutions might fail.
CHCNAV’s advanced GNSS receivers support both PPP and PPP-RTK corrections, enabling flexible deployment options for varied operational environments.
Post-Processing Kinematic (PPK)
Post-Processing Kinematic (PPK) has become increasingly important in the unmanned systems industry, particularly for drone mapping applications. CHCNAV’s CGO2.0 software provides robust post-processing capabilities that deliver superior accuracy in challenging environments where real-time corrections might be unreliable. The system offers exceptionally reliable corrections for aerial mapping missions, allowing operators to achieve consistent results even in difficult conditions. Its extended baseline capabilities enable operations over greater distances from the base station, while maintaining high precision. This makes it the optimal solution for mapping projects over water bodies or in mountainous terrain, where maintaining real-time communication links can be challenging.
Choosing the Right GNSS Correction Method
When selecting a GNSS correction method for unmanned systems, several key factors require careful consideration:
The operating environment plays a crucial role in determining the most effective correction method. Urban areas with good infrastructure might benefit from Network RTK solutions, while remote locations might require PPP or PPK approaches. The specific characteristics of the terrain and the overall coverage requirements will influence which solution provides optimal performance.
Accuracy requirements must be carefully evaluated against operational needs. Some applications demand real-time centimeter-level precision, while others can work effectively with post-processed results. The consistency of accuracy across the entire operation area becomes particularly important for large-scale autonomous operations.
Operational constraints shape the final decision significantly. The availability of communication infrastructure in the operation area, budget considerations including both initial investment and ongoing costs, and the technical expertise available within the team all impact the choice of correction method.
GNSS Future Perspectives
The unmanned systems industry continues to drive innovation in GNSS technology. CHCNAV remains at the forefront of this evolution, developing solutions that combine multiple correction methods to provide optimal positioning performance across various operational scenarios.
As autonomous operations become more prevalent, the integration of these correction methods with advanced navigation systems will play a crucial role in enabling precise, reliable, and safe unmanned system operations across industries.
Whether you’re operating mapping drones, autonomous ground vehicles, or other unmanned platforms, understanding and implementing the right GNSS correction method is crucial for successful operations. CHCNAV’s comprehensive range of GNSS solutions provides the flexibility and precision needed to meet these diverse requirements in the unmanned systems sector.