Mapping of some ionospheric characteristics over a restricted area using SIRM (simplified ionospheric regional model)

A simplified model is used for mapping, in a restricted area, some ionospheric characteristics expressed as functions of local time (LT), season, solar activity and geographic latitude. The statistical model is based on a Fourier analysis of the monthly medians of 7 VI stations in Europe. Only 12 Fourier coefficients are required to portray the annual behaviour of some selected ionospheric parameters in a given VI station. A good agreement is obtained by comparing this model with the simple linear regression method. Moreover, such Fourier coefficients are suitable to generate zonal ionospheric maps in universal time (UT) after a time conversion. A comparison between this model, the CCIR model and the experimental observations gives satisfying results