M_GIM: a MATLAB-based software for multi-system global and regional ionospheric modeling

The ionospheric delay must be modeled and analyzed as one of the main error sources affecting the Global Navigation Satellite Systems (GNSS). To make up for the absence of open-source software in ionospheric modeling, a multi-system global and regional ionospheric modeling software named M_GIM is introduced, produced based on the M_DCB, a GNSS satellite and receiver differential code biases estimating software, and redeveloped in MATLAB 2019b. The conventional dual-frequency carrier-to-code leveling (DFCCL) method is used in M_GIM, and up to quad-system (GPS/GLONASS/ Galileo/BDS) observations can be processed. After a series of experiments, the reliability of the software is evaluated, which verifies that the established global and regional ionospheric models have similar accuracy to most of the individual ionosphere associate analysis centers (IAACs) final and rapid global ionosphere map (GIM) products. Using this software, one can easily establish a reliable temporal and spatial variation model of the ionosphere, aiding ionosphere-related space weather research and precise navigation and positioning.

Automated summary

Ionospheric delay is a significant error source for GNSS, and it needs to be modeled and analyzed. To address the lack of open-source ionospheric modeling software, a multi-system global and regional ionospheric modeling software called M_GIM is introduced, based on the M_DCB. It has been evaluated and proved reliable, with similar accuracy to individual ionosphere associate analysis centers (IAACs) final and rapid global ionosphere map (GIM) products.