The relative daily variability of f0F2 and hmF2 and their implications for HF radio propagation
Article first published online: 7 DEC 2012
Copyright 1974 by the American Geophysical Union.
Volume 9, Issue 8-9, pages 749–756, August-September 1974
How to Cite
1974), The relative daily variability of f0F2 and hmF2 and their implications for HF radio propagation, Radio Sci., 9(8, 9), 749–756, doi:10.1029/RS009i008p00749., , and (
- Issue published online: 7 DEC 2012
- Article first published online: 7 DEC 2012
- Manuscript Revised: 3 MAY 1974
- Manuscript Received: 14 DEC 1973
The effect of the daily variability of f0F2 and hmF2 on the propagation conditions of an HF communication circuit has been studied in an empirical manner. The daily variability of f0F2 and hmF2 was determined by a detailed statistical analysis and the results were incorporated into a three-dimensional ionospheric model and ray-tracing program. During hours surrounding local noon, the relative day-to-day changes seen in both f0F2 and hmF2 are comparable while at all other times the daily variability of f0F2 substantially exceeds that of hmF2. In terms of HF propagation changes resulting from these changes in f0F2 and hmF2, it can be concluded that a knowledge of the critical frequency of the F2 region is much more important than that of hmF2 if account must be taken of the propagation changes resulting from the normal daily variability of the F2 region.