RTKLIB — The Complete Guide: Open-Source GNSS Processing to Centimetre Accuracy, RTK and PPK

RTKLIB is an open-source software package for processing raw GNSS observations, developed by Tomoji Takasu. It lets an inexpensive receiver or a drone reach accuracy that used to require costly equipment, and it underpins many commercial products in the field.

RTKLIB

Tomoji Takasu

Centimetre-level GNSS post-processing — open-source RTK and PPK.

Get it from the vendor

What you get

Real-time RTK — against a base station or an NTRIP stream from a network of permanent stations.
PPK — post-processed kinematic, for example for drone photos without many ground control points.
Static solutions — for long baselines and control points.
Multiple constellations — GPS, GLONASS, Galileo, BeiDou and QZSS.
Utilities — conversion from receiver formats to RINEX, and plots for quality checks.

What to know

The interface is dated, and using it correctly requires understanding the processing parameters: elevation masks, ambiguity resolution mode and observation quality. A “fix” solution does not guarantee accuracy if the parameters are wrong. A maintained community fork (demo5) is tuned for low-cost receivers and is very popular among drone users.

Related tools

To map drone photos once positions are corrected — WebODM. To collect field data with a GNSS receiver — QField. For coordinate conversion and display on a map — QGIS.