The objective of this project is to establish a single-frequency GNSS positioning regional ionospheric mitigation service over the eastern Mediterranean based on the more accurate representation of the state of the ionosphere.
This improvement will be possible through the adjustment of the NeQuick-G algorithm, which is the basis for the ionospheric single-frequency GNSS correction algorithm adopted by GALILEO GNSS system, using ionospheric characteristics measured over Cyprus. The proposed service will depend on a modern digital digisonde (DPS-4D) and a collocated dual-frequency total electron content (TEC) monitor in Cyprus in the frame of real time monitoring of ionospheric propagation predictions.
The long-term improvement provided by the proposed service will be primarily depend on the dataset of a modern digital digisonde (DPS-4D) compiled over the last eight years. The short-term improvement provided by the proposed service will depend on total electron content (TEC) data provided by a GNSS reference station in the context of real time monitoring of ionospheric propagation predictions.
This service will aid towards improved representation of the regional ionosphere in its median (long-term) as well as near real-time representation and will therefore reduce ionospheric positioning errors both in a climatological sense but also in a weather-like mode of NeQuick-G in the frames of the Galileo system operation.
The operation of this novel service will facilitate improvement of CCIR files that define the ionospheric electron density profile and therefore provide a direct indication of the extent of the positioning errors which directly affect the trans-ionospheric propagation of GNSS satellite signals under quiet geomagnetic conditions. The data observations will be processed and ingested into the NeQuick model by adjusting its relevant parameters (anchor points of the electron density profile and the Az ionisation level) and the users will have the option to download files that represent more accurately the median behaviour of the local ionosphere or even to update these files more often in a near-real time operation mode.
This service will ultimately propose a novel regional mode for ionospheric positioning error mitigation that may be fully or partially adopted in other parts of the globe as a means to enhance the accuracy of single-frequency positioning devices.