Modern Ionospheric Ray Tracer for Earth Observation Satellite Missions

Electromagnetic waves propagation through the ionosphere is subject to several effects including refraction, absorption, signal delay, or Faraday rotation. A ray tracer propagator that simulates these effects is an important tool for all satellite missions relying on transionospheric communications and Earth observation. This study presents an update to the 1975 Jones and Stephenson IONORT's code by implementing the use of up-to-date ionospheric, atmospheric, and geomagnetic models (International Reference Ionosphere or NeQuick, NRLMSISE-00, and International Geomagnetic Reference Field), and a new 3-D model for equatorial plasma bubbles. The developed code is part of the Ionosphere Modular Software Package in the context of the European Space Agency project SIMIONO. High-frequency radar sounders, synthetic aperture radars, and GNSS reflectometry missions constitute the main application of this software. The ray tracer has been validated with respect to the original software and by comparing real versus simulated vertical ionograms in different locations and dates.