If you’ve researched drone mapping or LiDAR technology, you’ve likely come across the terms PPK and RTK. While they are often mentioned together, they’re not the same thing. In fact, they work together to improve the positional accuracy of drone survey data. The differences can get very technical and in depth, however, this blog will discuss them at the simplest level.
Understanding the basic differences between PPK and RTK can help project teams better understand how high-accuracy aerial mapping is achieved and why different workflows may be used depending on the project.
What Is RTK?
RTK, or Real-Time Kinematic, is a positioning method that improves a drone’s GPS accuracy while it is flying.
During an RTK flight, the drone receives correction data from a base station or correction network in real time. As each image or LiDAR point is collected, its position is continuously refined, allowing the drone to capture survey-grade location information as it flies.
Because these corrections occur during the flight, RTK can streamline data collection and reduce the amount of post-processing required.
What Is PPK?
PPK, or Post-Processed Kinematic, takes a different approach.
Instead of applying GPS corrections while the drone is in the air, PPK records the drone’s positioning data during the flight and applies corrections afterward using data from a base station or other known reference source. This post-processing workflow refines the recorded positions once the mission is complete.
By processing the data after the flight, PPK can correct positioning information even if a continuous real-time correction link wasn’t available throughout the mission.
The Biggest Difference
Although RTK and PPK both aim to improve positional accuracy, the primary difference is when the GPS corrections are applied.
With RTK, corrections are received and applied while the drone is flying. With PPK, the drone records the necessary positioning information during the mission, and the corrections are calculated after the flight has been completed.
Why Does This Matter?
Both workflows are capable of producing highly accurate mapping data when used correctly. However, each has advantages depending on the project.
RTK works well when a reliable connection to a base station or correction network can be maintained throughout the flight. Because corrections are applied in real time, data is ready for processing immediately after collection.
PPK offers greater flexibility in environments where maintaining a continuous connection may be difficult. If the real-time correction signal is interrupted by terrain, vegetation, buildings, or other obstacles, the recorded positioning data can still be refined during post-processing. This makes PPK particularly useful for remote or challenging project sites.
Is One Better Than the Other?
Not necessarily. Rather than competing technologies, RTK and PPK are two different workflows for achieving accurate positioning. The right choice depends on the project’s location, available equipment, and accuracy requirements.
Many modern drone mapping systems use RTK-enabled hardware while also supporting PPK processing. This gives survey teams the flexibility to collect accurate data in the field while retaining the option to further refine positional information during processing when appropriate.
Final Thoughts
PPK and RTK both improve the positional accuracy of drone mapping, but they do so using different workflows. RTK applies corrections during flight, while PPK refines the data after the mission has been completed.
Understanding the distinction helps explain how modern drone mapping systems achieve the level of accuracy needed for construction, engineering, surveying, and land development projects.
At Summit LiDAR, we select the workflow that best fits each project’s needs, helping our clients receive reliable, high-quality aerial data they can confidently use for planning, design, and decision-making.
