A modern, resilient approach to drone GNSS post‑processing for land surveyors and engineering teams.
Surveyors have relied on GPS since the earliest days of the technology. What has changed dramatically over the last several years is what professional teams can extract from modern GNSS. Classic approaches, including on‑site RTK for immediacy and single‑base PPK, still deliver solid results. But more and more projects now demand better accuracy across tougher sites, with fewer fragile dependencies on things like cell coverage or a single base station battery. The question many teams ask is simple: how do we get repeatable, survey‑grade results even when the field throws us curveballs?
That is exactly the problem Aerotas ATK was built to solve. ATK is Aerotas’ GNSS post‑processing methodology for drone mapping that treats every project like a small network adjustment. Rather than relying on a single correction stream or a single baseline, ATK fuses many sources of information while pushing the boundaries of what is possible in post-processing with the most advanced technologies in existence. In practice that means we combine multiple satellite constellations, multiple receivers, and cutting edge estimation techniques to squeeze a precise trajectory out of whatever the field gives you. The result is geolocation data that is not just accurate when everything goes well, but resilient when something doesn’t.
How ATK Works
At the heart of ATK is the idea that more independent lines of evidence lead to better positioning. We start by gathering observations from the four major constellations (GPS, GLONASS, BeiDou, and Galileo) across as many frequencies as the drone and bases can provide. Those observations are paired with the most current precise satellite products available: orbits, clocks, and phase‑bias information that describe where each satellite actually was and how its signal behaved. With that foundation, the ATK engine runs multiple complementary branches. One branch performs differential processing (PPK) between the drone and one or more base stations; the other branch performs PPP with ambiguity resolution (PPP‑AR) to estimate an absolute solution directly from the constellations. Both branches are then reconciled and stress‑tested with network least‑squares techniques that explicitly consider site location, data quality, baseline distances, and prevailing sky conditions.
Ideal projects provide four categories of input: the drone’s raw multi‑frequency logs; precise satellite products from Nasa; a short‑baseline local base (typically under five kilometers); and public base data from permanent stations within roughly one hundred kilometers. When all four are present, ATK exploits the short‑baseline geometry for tight relative precision while using the broader network to lock the absolute frame. When one or more sources are missing, if a base dies mid‑mission, a CORS station is offline, or there is simply no cell coverage, ATK falls back gracefully by leaning on the remaining inputs and the PPP‑AR branch. Because both branches are always running, there is no single point of failure.
In field terms, think about three common scenarios. On a canyon job, a local base may see half the sky while the drone spends much of the flight in and out of view; ATK leverages the overlapping segments and uses PPP‑AR to stabilize the absolute frame. On a remote site, there may be no practical way to place a local base at all; ATK works directly from the drone logs and the precise products to deliver a defensible absolute trajectory. On a suburban site with unreliable cellular coverage, an otherwise clean RTK workflow can collapse unexpectedly; ATK treats those same observations as raw material for a multi‑source solution that does not depend on a live correction stream.
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What You Can Expect
Because Aerotas has served the land surveying industry since 2014, accuracy is not an aspiration, it is what everything else is built around. In typical conditions, single‑flight precision, even without a local base station, lands around 1–2 cm, which is often enough to avoid a re‑flight even with significant in-flight errors. Global absolute accuracy is roughly 10 cm worldwide without any supporting base station data, and typically 3–5 cm in the continental United States, where dense public networks and our region‑tuned models provide an advantage. When ATK outputs are paired with our photogrammetry or LiDAR alignment workflows, whole‑project accuracy commonly converges near 3 cm.
We are careful about how we back those numbers. ATK results are validated against independent checks: long‑duration OPUS occupations on stable marks, total‑station control networks, and cross‑comparisons among GNSS, IMU, photogrammetry, and LiDAR observations. We document methods and outcomes according to the ASPRS Positional Accuracy Standards for Digital Geospatial Data, because the proof matters as much as the result. The consequence for your team is straightforward: fewer re‑flights, fewer surprises in office QA, and a cleaner handoff to downstream tools.
Project reliability is another critical pillar. ATK is engineered to keep working when individual components do not. If a local base battery dies, a nearby CORS is down for maintenance, or a site has no cell signal for real‑time corrections, ATK still has multiple ways to build a trajectory. That resilience translates directly into schedule and budget protection. Even better, it creates flexibility. Where you launch from, where you can place a base, and how long you can log all matter less. Work the site safely and efficiently; ATK is designed to meet you where you are rather than forcing a single rigid playbook.
From an adoption standpoint, the process is straightforward and intentionally light‑touch. You simply send the drone’s RINEX (or native logs) and optional local‑base data if you have it. We perform ATK processing, photogrammetry, lidar analysis, and linework drafting, and return a complete, survey‑grade map. Aerotas has been helping surveyors create better, more accurate, and more reliable maps for over a decade.
The additional details often make the difference on the margins. ATK can run from a single drone observation file when that is all you have, but results always improve with more information. Short occupations on a local base can be surprisingly helpful; so can long‑baseline permanent stations, even at fifty to one hundred kilometers, because they anchor the solution to a consistent frame over time. Under current standards and product availability, single‑flight precision remains at the 1–2 cm level in most conditions without a base. Absolute accuracy depends more heavily on the presence and quality of local or permanent bases and on the day’s atmospheric behavior, which is why the continental U.S. typically outperforms the global average. When the project includes both imagery and LiDAR, ATK feeds each modality and we then use flight‑to‑flight alignment to tighten the final network. In many cases, overall project accuracy closes near 3 cm without the overhead of dense ground control.
None of this removes the need for professional judgment. Field best practices still matter: place bases on solid marks with measured antenna heights, log at appropriate rates, maximize sky view when practical, and make note of any timing or lever‑arm changes. And while ATK reduces dependence on ground control, Aerotas continues to recommend control points and/or check shots for survey deliverables. They are essential for proof for you, for your clients, and for public agencies that must defend their records.
Looking Ahead
We designed ATK to evolve to meet new challenges our clients face in the field. With tens of thousands of aerial surveys processed across every type of terrain in the US, Aerotas has built one of the largest GNSS datasets in the industry. That real-world foundation drives continuous improvements to the algorithms inside ATK, bringing survey-level accuracy anywhere – with less friction, fewer dependencies, and no need for fixed local bases or dense ground control.
Picture what that means for your team. No full-day base setup, two-hour base occupation — just efficient flying and dependable results. Back in the office, ATK reconciles the data against precise products and public stations to produce a map that stands up to the most rigorous checks. The result is simple: fewer re-flights, faster delivery, and accuracy that holds up under client and agency scrutiny.
If that’s the kind of reliability you want in your workflow, let’s talk. We’ll review how you currently handle GNSS on drone projects, identify where you lose time or accuracy, and run a low-risk trial on one of your recent datasets. Best case, you see immediate gains in efficiency and precision. Worst case, you gain a clear understanding of where your current process already performs well.
Curious how ATK would perform on your next project? Schedule a free 20-minute consult — we’ll walk through your workflow, show where ATK adds the most value, and help you capture everything your drone is capable of delivering.
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