[Ionosphere] Need to understand collision frequency in E layer

Hi all,



I am trying to understand about collision frequency that happened in ionosphere layer. In D region, below 90 km [Wait and Spies 1964] the ionospheric electron-neutral collision frequency given as



v(h) = 1.816x10e11 exp(-0.15h)



I just wondering, to who ever really expert in this area, is it for E-region (the area between 90-120km altitude), the same equation can be used to measure collision frequency? as I know, the collision rate is different for different height.



thank you in advance.