Sub-Commission 4.1: Emerging Positioning Technologies and GNSS Augmentations
Sub-Commission 4.2: Multi-frequency Multi-constellation GNSS
Sub-Commission 4.3: Atmospheric Remote Sensing
Sub-Commission 4.4: GNSS Integrity and Quality Control
Study Groups, Joint Study Groups and Joint Working Groups
SG 4.1.1 Positioning using smartphones
SG 4.1.2 Positioning and Navigation in Asian Urban Canyons
JWG 4.3.1 Real-time ionosphere monitoring and modelling (joint with IGS and GGOS)
JWG 4.3.4 Validation of VTEC models for high-precision and high resolution applications (joint with IGS, GGOS and Comm. 1)
JSG 4.4.4: Assessment and validation of IGS products and open-source scientific software (Joint with IGS)
JSG from other leading commissions joint with Commission 4, SC 4.3:
- JSG 1: Coupling processes between magnetosphere, thermosphere and ionosphere (IAG ICCT, joint with GGOS Focus Area on Geodetic Space Weather Research)
JWGs from other leading commissions joint with Commission 4, SC 4.3:
- JWG 1: Electron density modelling (GGOS Focus Area on Geodetic Space Weather Research)
- JWG 2: Improvement of thermosphere models (GGOS Focus Area on Geodetic Space Weather Research, joint with ICCC)
- JWG 3: Improved understanding of space weather events and their monitoring by satellite missions (GGOS Focus Area on Geodetic Space Weather Research)
- JWG 1.x.x: Intra- and inter-technique atmospheric ties (Comm. 1)
- JWG x: Zenith Total Delays and gradients quality control for climate (ICCC, joint with Comm. 4)