Tropospheric Scintillation at Ka-Band Over a Hilly Tropical Region

Satellite signal at the Ka-band is measured at a hilly, high rain fall region, Umiam, Shillong (25.6768° N, 91.9270 °E) for three years using GSAT 14 satellite. Scintillation has been extracted using a Butterworth filter of tenth order and 0.025 Hz cutoff frequency. Experimental results are then compared with the existing ITU-R scintillation model, Karasawa model, Van de Kamp model, and Ortgies-T model. Deviation of the above-mentioned models from measured data is then studied. The ITU-R model is found to be the best while Ortgies-T is found to be the worst performer over this region. New parameterization for the ITU-R scintillation model for the Ka-band is further proposed for this region based on one year of measured data and validated against other two years of data of 20.2 GHz. The results indicate the improved performance of the proposed model with a very high correlation value.