Results From Simultaneous Ka- and X-Band Long-Term Satellite Propagation Measurements at Low Elevation Angle in the Arctic

Ka- and X-band are used for earth observation satellite data downlink and governmental satellite communications, with a gradual shift towards the higher frequencies. This paper presents results from three years of beacon measurements at 7.6 and 20.7 GHz at an elevation angle of <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$6.1$</tex> I at <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$70^\circ\mathrm{N}$</tex> in Norway. For 99% of the time the results show excess attenuation levels of 0.5 dB at X-band and 2.6 dB at Ka-band. For tropospheric scintillation the 99% levels are 0.6 and 1.1 dB at X- and Ka-band, respectively. The ITU-R model predictions for rain attenuation agree well with the measurements, especially when local rain data are used. For scintillation, the ITU-R model gives higher than measured levels while a recent model developed from arctic data gives too low annual predictions but fits very well on monthly basis.