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the two is that Kanoya② is lower by about 1.5 dB as compared to Kanoya①. e cause is due to rainfall. Measured values showed good agreement with theoretical calculations (the red curve in the gure) with a standard deviation of 0.48 dB. Figure 9 shows received C/N0 sent from the Chubu beam of the MBA (while measurements were taken in West Japan along the coast of the Sea of Japan) against the distance from the beam center. e measured values also showed good agreement with theo-retical calculations with their deviation falling within ±1 dB.e three plots in Fig. 10 show the measured data obtained in the section connecting Uwajima and Kochi. e vertical axes of these plots represent: (a) Doppler frequency, (b) azimuth angle of the mounted antenna, and (c) moving velocity of the vehicle earth station. In view of the fact that the satellite is located directly south of the vehicle earth station, Doppler frequency is expected to show positive values if the vehicle earth station moves to-ward south, and negative value if it moves toward north. e experiment demonstrated that this relation holds in-deed. Figure 11 shows CDF of Doppler frequency measured along the whole extent of the Shikoku-Kinki area route. e maximum Doppler frequency in this area was 1,094 Hz.Doppler frequency fd is dened as:= (1)Where, v represents the moving velocity[m/s], θ repre-sents the incident angle of radio waves relative to the traveling direction, and λ the wavelength [m]. By substitut-ing the following three values into equation (1) — Beacon signal central frequency 18.9 GHz, antenna elevation angle 41.3°, and moving velocity 100 km — we get the maximum FiF12　Measurement points used in the data propagation experimentSakaideWakayamaKushimotoMuroto-misakiAshizuri-misakiUwajimaTokushimaKochiTobaFiF13　Network configuration used in the data propagation experimentWINDSVehicle earth stationFixed earth stationPC for link monitoringEach measuring point earth stationPC for link monitoringNICT Kashima Space Technology CenterFiF10Measured data obtained in the sections between Uwajima and Kochi0200040006000800010000経過時間[s](a)ドップラ周波数-100001000ドップラ周波数[Hz]0200040006000800010000経過時間[s](b)方位角-1000100アンテナ方位角[度]0200040006000800010000経過時間[s](c)速度050100速度[km/h](a)Doppler frequency(b)Azimuth angle(c) VelocityDoppler frequency[Hz]Antenna azimuthangle [deg]Velocity [km/h]Elapsed time [s]Elapsed time [s]Elapsed time [s]FiF11　CDF of Doppler frequencyDoppler frequency[Hz]3 Ultra-High-Speed Satellite Communication Technology162　　　Journal of the National Institute of Information and Communications Technology Vol. 64 No. 2 (2017)