A Computation Of Incoherent Scatter Spectra In The High-latitude Auroral Ionosphere

In this dissertation, according to the theory of the incoherent scatter, the effects of the non-equilibrium inosphere plasma incoherent power spectra and the related theory and experiment are investigated. The current incoherent scatter radar data analysis and processing is based on the standard Maxwellian distribution, however, non-Maxwellian distribution characteristics of the ionospheric plasma can be induced by high power radio wave heating, particle settlement and two-stream instabilities, etc. All this will make distribution function depature from the distributon of stability, and the result of the inversion of the inosphere plasma parameter may cause error and even wrong. Consequently, this dissertation is focused on the incoherent scatter spectra with the non-Maxwellian distribution, this is basic theory for modifing the inversion programe of the incoherent scatter radar. Based on the principle of the incoherent radar for detecting the inosphere and EISCAT, the main topics and results are as follows:Firstly, according to the theory of the incoherent scatter, the effect of diverse ion component on incoherent scatter spectra in stable state is studied.Secondly, using Boltzmann's equation, the solution of intergral for the relaxtion models, the solutions of the totus distribution and generalized orthogonal polynomialare presented, the corresponding incoherent scatter spectra are simulated.Thirdly, the phenomenon of naturally enhanced ion-acoustic lines (NEIALs) at high-latitude is presented, the ion-ion two-stream instable, the bump-on-tail and field-aligned currents instable result naturally enhanced ion-acoustic lines is discussed.Finally, the data processing of EISCAT and the analyzing software are introduced, and using the EISCAT data for the enhanced ion-acoustic lines occuring, the characteristic of the spectra at naturally enhanced ion-acoustic lines occuring is analyzed, non-equilibrium state inosphere plasma parameter extract is elementary studied.