PPP vs PPK vs RTK: Complete Comparison for Precision GNSS Positioning
RTK supplies relative positioning in real time, PPK computes a relative solution after recording, and PPP uses precise satellite products without a nearby base receiver. Choose by required delivery time, reference-data availability, observation quality and the accuracy you can independently verify.
Three paths to centimeter-level positioning
Precise GNSS workflows use carrier-phase observations with models and corrections for satellite, receiver and propagation effects. RTK and PPK are commonly relative methods, while PPP uses precise satellite products. All require suitable observations and verification; no method name alone guarantees centimetre or millimetre accuracy.
Core technical comparison
| Parameter | RTK (Real-Time Kinematic) | PPK (Post-Processed Kinematic) | PPP (Precise Point Positioning) |
|---|---|---|---|
| Mathematical Model | Double-differenced carrier phase | Double-differenced carrier phase | Undifferenced code and phase; model depends on strategy |
| Base Station Required? | Yes (Dedicated base or NTRIP CORS) | Yes (Local base or public CORS) | No (Single autonomous receiver) |
| Maximum Baseline | Depends on atmospheric correlation, network corrections and conditions | Depends on reference data, atmosphere and processing model | No local baseline; needs compatible satellite products |
| Communication Link | UHF radio or Cellular (NTRIP) | None required in the field | None (Internet connection for orbit download) |
| Solution Timing | Real-time (sub-second latency) | Post-mission (after data download) | Post-mission (or real-time with SSR corrections) |
| Convergence Time | Variable ambiguity initialisation | Variable; processed after recording | Depends on observations, products and ambiguity strategy |
| Accuracy assessment | Check fixed solution and independent control | Check trajectory, residuals and base coordinates | Check convergence, residuals, frame and independent control |
| Primary Use Case | Construction stakeout, boundary surveying | Drone LiDAR/PPK, aerial photogrammetry | Geodetic control networks, remote CORS, maritime |
When to choose RTK
Real-Time Kinematic is indispensable when immediate coordinates are required on the ground — such as civil construction stakeout, topographic surveys, and agricultural machine guidance. However, RTK depends on an uninterrupted wireless data link (UHF radio or cellular NTRIP). In mountainous terrain, offshore locations, or remote forests where radio line-of-sight fails or cellular coverage drops, correction availability is reduced, and the solution may degrade depending on the receiver and the outage.
When to choose PPK
PPK is useful when a trajectory can be delivered after a mission and overlapping base observations are available. It removes dependence on a live correction link during acquisition. Some engines combine forward and backward processing, but post-processing cannot guarantee recovery of missing or obstructed observations. Check phase continuity, base coordinates and antenna metadata.
When to choose PPP
Precise Point Positioning eliminates the base station entirely. Instead of differencing observations against a local reference station, PPP uses global satellite orbit and clock corrections derived from worldwide tracking networks (such as IGS, CODE, and GFZ). This makes PPP ideal for establishing new geodetic control networks, monitoring crustal deformation, surveying in remote deserts or offshore oceans, and validating CORS station coordinates without regional network dependencies.
How PosFlow supports your positioning workflow
PosFlow publishes PPP and PPK workflows through Apex. Review the processing guide for supported modes, accepted inputs and availability before starting a job. Run QC on the observations first and retain the resulting products, settings and report for verification.
References and methodology
Technical definitions follow the sources below. Worked examples are illustrative; product-specific thresholds are identified as PosFlow settings. For corrections, contact PosFlow with the article URL and the relevant specification.