The Structure of the Sporadic E Layer Detected from VHF Ionospheric Propagation

From the statistical result of sporadic E propagation carried out on the frequency of 50 Mc/s, there is, in general, a fairly good correlation between the received field intensity and the critical frequency of the sporadic E layer measured at apex. This relation, however, is not always vahd for each case; i.e., the transmission loss of the received signal depends not only on the value of f 0 E s ;, but also on the layer thickness and the distribution of electron density within the layer. The distribution of electron density in the sporadic E layer is deduced from both data of transmisssion loss and critical frequency at apex, if the sporadic E layer is assumed to be an extremely thm ionized layer.