Comparison of Observed and Predicted Basic Maximum Usable Frequency Using High Frequency Propagation

Abstract

This study compares the observed data from ionosonde measurements with the expected data from the frequency parameter (foF2) International Reference Ionosphere (IRI) model and the Basic Maximum Usable Frequency, denoted by the F2-Layer BMUF. This work involved (12) monthly median year data (2001, R12=111) selected for high sunspot numbers and years for low sunspot numbers (2004, R12=44) and (2005, R12=29) to investigate the effect of solar activity on the mid-latitude BMUF values observed and predicted over Wakkanai station (45.38o N, 141.66o E).  The data analysis shows that there is a strong correlation between the observed and projected values for both foF2 with the exception of January 2001 and 2004, and BMUF for low sunspot years and for all months with the exception of months 1, 9 and 12 of 2004. However, the negative correlation of high solar activity for the year 2001 is noted. The fitting procedure, a correction factor as a function of time, was used to correct the predicted value of BMUF for 2001 to boost the performance of the IRI model.