Some aspects of small-scale stratifications at E-layer and F2-layer levels of the daytime mid-latitude ionosphere

Limited range ionosonde recordings have shown that in mid-latitude regions the daytime E-region is often disturbed and small-scale stratifications can be observed regularly on ionograms. The true range separations between stratifications vary from 1 to 8 km with a well-pronounced peak for separations in the range 2 to 2.5 km. Also, fixed-frequency recordings near the daytime penetration frequency of the F2-layer have shown the continuity of the virtual - height changes which occur to the quasi-horizontal-trace (QHT) segments of the F2-layer traces. These segments are often observed when travelling ionospheric disturbances (TIDs)are present. On the fixed-frequency recordings particular traces (associated with the QHT segments) are seen to change virtual range at a much greater rate than the background layer