Fig. 1

An approximate representation of vertical electron density profile between \(h_{min}\) and \(h_{max}\); the quantities \(N_m^Q( =\) maximum value of the electron density, peak density), \(h_m^Q( =\) peak height) and \(H^Q( =\) scale height) are the key parameters of the ionosphere layer Q with \(Q \in \{D, E, F_1, F_2 \}\). Figure is adapted from Limberger (2015) and is not to accurate scale, but is merely meant for illustration purpose. For a more detailed description of ionospheric profile shape, see e.g. Davies (1990)