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Zusammenfassung:
Global Positioning Satellite (GPS) measurements made by the Canadian High Arctic Ionospheric Network (CHAIN) are used to scrutinize the distortion seen in the trans-ionospheric radio signal. The analysis of ground measurements of the radio signal can therefore contribute for the understanding the plasma instability mechanisms that generate electron density structures in the ionosphere (irregularities). In this work, we describe the radio signal spectral characteristics in the auroral region (Churchill). We present examples of phase spectrum with two-components characterized by a stepper spectral slope at small scales irregularities, and a shallower slope at larger scales. The breaking point frequency is larger than the Fresnel frequency in the most cases. In return, the amplitude scintillation spectra always exhibit a single slope power behaviour. The phase spectra are examined within a two-components model developed by Fremouw et al. [1980]. In this model, the component associated with large scale electron density fluctuations is responsible for low frequency phase variations (geometrical-optics), while the small-scales produce diffractive patterns responsible for the generation of the high frequency fluctuations.
