Global ionospheric propagation model (GIM): A propagation model for scintillations of transmitted signals

The characteristics of random ionospheric inhomogeneities are described, including their dependency on the geophysical parameters. They are used in a propagation model to estimate the propagation errors and the fades of the transmitted signals. Margins to be included in a budget link are subsequently determined. Features of our propagation model, Global Ionospheric Propagation Model (GIM), are presented with typical results for VHF and L band links.