GNSS Processing

GNSS (Global Navigation Satellite Systems) processing enables precise positioning, crustal deformation monitoring, atmospheric studies, and geodetic research.

---

📡 GNSS Constellations

• GPS (USA)
• GLONASS (Russia)
• Galileo (Europe)
• BeiDou (China)
• QZSS (Japan)
• IRNSS/NavIC (India)

---

🛰️ Types of GNSS Processing

1. Static Processing

High accuracy for geodesy & crustal deformation.

2. Kinematic Processing

Positioning for navigation, UAVs, surveying.

3. PPP — Precise Point Positioning

Uses precise clocks & orbits for global accuracy.

4. RTK — Real-Time Kinematic

Centimeter accuracy using base–rover architecture.

5. GNSS Interferometry

Tropospheric delay estimation & atmospheric sensing.

---

🔧 Open-Source GNSS Tools

RTKLIB

Standard for open-source RTK/PPP processing.
🔗 https://github.com/tomojitakasu/RTKLIB

GPSTk

Toolkit for GNSS processing & simulation.
🔗 https://github.com/SGL-UT/GPSTk

GAMIT/GLOBK (free academic license)

Network adjustment & GNSS geodesy.
🔗 https://geoweb.mit.edu/gg/

TEQC (archived)

RINEX editing, quality checking.
🔗 https://www.unavco.org/software/data-processing/teqc/teqc.html

PyGNSS

Python utilities for GNSS analysis.
🔗 https://github.com/iondynamics/pygnss

---

🌍 GNSS Data Sources

UNAVCO / EarthScope GPS Networks

High-rate GNSS data.
🔗 https://www.unavco.org

IGS — International GNSS Service

Global data & precise products (SP3, CLK).
🔗 https://www.igs.org

SOPAC Data Portal

Southern California geodetic data.
🔗 https://sopac.ucsd.edu

---

🎥 YouTube Playlists

• GNSS Data Processing (Lectures)
  🔗 https://www.youtube.com/results?search_query=gnss+processing+tutorial

• RTKLIB Tutorials
  🔗 https://www.youtube.com/results?search_query=rtklib+tutorial

---

📘 Additional Learning

• ESA GNSS Education Portal
  🔗 https://www.esa.int/Applications/Navigation