Three-dimensional numerical ray tracing on a phenomenological ionospheric model
Article first published online: 22 OCT 2010
Copyright 2010 by the American Geophysical Union.
Volume 45, Issue 5, October 2010
How to Cite
2010), Three-dimensional numerical ray tracing on a phenomenological ionospheric model, Radio Sci., 45, RS5017, doi:10.1029/2010RS004359., , and (
- Issue published online: 22 OCT 2010
- Article first published online: 22 OCT 2010
- Manuscript Accepted: 29 JUL 2010
- Manuscript Revised: 21 JUN 2010
- Manuscript Received: 14 JAN 2010
- ray tracing;
- HF radio propagation
 In this paper we present a numerical and step by step ray-tracing method on a phenomenological ionospheric electron density (Ne) model, the TaiWan Ionospheric Model (TWIM), which is constructed from the FormoSat3/Constellation Observing System for Meteorology, Ionosphere and Climate (FS3/COSMIC) ionospheric radio occultation data. With the Earth's magnetic field and horizontal Ne gradient effects included, efficient methods for calculating ray parameters such as the ground range, reflection height, phase path, and group path are presented. The three-dimensional TWIM consists of vertically fitted α-Chapman-type layers, with distinct F2, F1, E, and D layers, for which the layer parameters such as peak density, peak density height, and scale height are represented by surface spherical harmonics. This way the continuity of Ne and its derivatives is maintained. This is important for practical schemes for providing reliable radio propagation predictions. The methodology is successfully applied to a practical high-frequency transmitter for oblique incidence ray tracing and further evaluated by comparing synthetic vertical ionograms generated by the method with experimental ionosonde observations.