Simulation study of the interaction between large-amplitude HF radio waves and the ionosphere
Abstract
The time evolution of a large-amplitude electromagnetic (EM) wave injected vertically into the overhead ionosphere is studied numerically. The EM wave has a carrier frequency of 5 MHz and is modulated as a Gaussian pulse with a width of approximately 0.1 milliseconds and a vacuum amplitude of 1.5 V/m at 50 km. This is a fair representation of a modulated radio wave transmitted from a typical high-power HF broadcast station on the ground. The pulse is propagated through the neutral atmosphere to the critical points of the ionosphere, where the L-O and R-X modes are reflected, and back to the neutral atmosphere. We observe mode conversion of the L-O mode to electrostatic waves, as well as harmonic generation at the turning points of both the R-X and L-O modes, where their amplitudes rise to several times the original ones. The study has relevance for ionospheric interaction experiments in combination with ground-based and satellite or rocket observations.
- Publication:
-
Geophysical Research Letters
- Pub Date:
- March 2007
- DOI:
- 10.1029/2006GL028948
- arXiv:
- arXiv:physics/0612038
- Bibcode:
- 2007GeoRL..34.6106E
- Keywords:
-
- Computational Geophysics: Numerical solutions (4255);
- Ionosphere: Active experiments;
- Ionosphere: Plasma waves and instabilities (2772);
- Ionosphere: Wave propagation (0689;
- 3285;
- 4275;
- 4455;
- 6934);
- Physics - Plasma Physics;
- Physics - Space Physics
- E-Print:
- 6 pages, 7 figures