Limitations and possible improvements of ionospheric models for radio propagation: Effects of sporadicElayers

摘要: Recent angle of arrival measurements echoes reflected from sporadic E layers show that those are frequently tilted in different directions with deviations the horizontal ranging up to 30°. The observations also indicate structure sizes Es relatively small, on order 50 km. Strong tilts can launch HF rays into whispering gallery mode, and cause large errors direction finding. They permit interpretation nonblanketing as a geometrical effect not an optical property. consequences findings for modelling will be discussed.