GPS / GNSS
GPS / GNSS Surveying Methods Compared
Summary
GNSS surveying positions points from satellite signals of GPS, GLONASS, Galileo and BeiDou. Methods range from static sessions of an hour or more (millimetre-level control) to RTK in seconds (centimetre-level detail). The right method depends on accuracy, productivity, communication and reference frame requirements.
Definition
GNSS surveying: precise positioning using carrier-phase observations from global navigation satellite systems.
- Static: mm-level control
- RTK: cm-level in seconds
- PPP: no base needed
- Heights are ellipsoidal
Methods compared
| Method | Typical horizontal accuracy | Occupation | Typical use |
|---|---|---|---|
| Static | 3–5 mm + 0.5 ppm | 30 min – several hours | Primary control, deformation |
| Rapid static | 5–10 mm + 1 ppm | 5–20 min | Secondary control |
| RTK / network RTK | 8–20 mm + 1 ppm | Seconds | Detail, stakeout |
| PPK | 10–20 mm | Seconds to minutes | Drones, areas without communications |
| PPP | 2–10 cm (converged) | 20 min – hours | Remote control points |
Reference frames and epochs
GNSS coordinates belong to a reference frame realized at an epoch, such as ITRF2014 at 2017.0 or a national frame like KSA-GRF17. Plate motion of several centimetres per year means mixing epochs or frames causes real errors. See datum transformations.
Heights
GNSS heights are ellipsoidal (h). Orthometric heights (H) need a geoid model: H = h − N.
FAQ
What is the difference between GPS and GNSS?
GPS is the US system. GNSS is the general term covering GPS, GLONASS, Galileo, BeiDou and regional systems. Modern receivers track several.
Which method should I use for control?
Static or rapid static with redundant baselines, processed and adjusted as a network.
Related tools and articles
Tools
- Field Visit SurveyRecord and check field observations.
- Coordinate TransformationConvert between EPSG coordinate systems.
Articles
- RTK GNSS Surveying: Accuracy and Quality ControlReal-time kinematic (RTK) GNSS uses carrier-phase measurements and corrections from a base station or network …
- Static SurveyReference topic
- GNSS Quality ControlReference topic
- WGS 84: World Geodetic System 1984WGS 84 is the global geodetic reference system used by GPS. It defines an ellipsoid (a = 6 378 137 m, 1/f = 29…
References
- NOAA National Geodetic Survey. Guidelines for Real Time GNSS Networks and NGS-58/59 GNSS height guidelines.
- Hofmann-Wellenhof, B., Lichtenegger, H. & Wasle, E. GNSS – Global Navigation Satellite Systems, Springer, 2008.
Cite this page
GeoCAD Bridge. “GPS / GNSS Surveying Methods Compared.” GeoCAD Bridge Knowledge Center, updated 2026-10-05. https://www.geocadbridge.com/knowledge/survey-gps-survey/