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Fig. 1, the earth station is mounted on a van.e antenna system mounted on the vehicle earth sta-tion is capable of automatically detecting and tracking the satellite, for which exact positioning of the earth station (determined by GPS signal) and Beacon signal level (global beam from the satellite) are used. ese features enable the vehicle earth station to link with the satellite even while it is running. e Beacon signal in this context means the residual carriers of network monitoring infor-mation (telemetry radios for Mission Planner). Other fea-tures such as HD cameras and wireless LAN access points are also installed in the earth station as an eective function for emergency / disaster.3Propagation measurement experiment3.1 Experimental methodIn this experiment, the vehicle earth station on the move received an 18.9 GHz Beacon signal (sent from WINDS) for evaluation of received signal power. e Beacon signal was evaluated using a spectrum analyzer at every 100 ms for the peak received power and frequency. On the expressway, the maximum speed of the vehicle was 100 km/h.e routes selected for measurement include those envisaged to be most vulnerable to a Nankai Trough Earthquake and subsequent tsunami: the coastal roads of the Shikoku and Kinki areas facing the Pacic Ocean (Fig. 2), coastal roads from Oita to Kagoshima (Fig. 3), and coastal roads facing the Japan Sea from Shimane to Toyama (Fig. 4). Measurements were taken while the car was on the move. Each plot of these gures is color coded illustrat-ing the power of the Beacon signal (the sections plotted in blue indicate lowered intensity due to shadowing or other factors). Note that the signal intensity was normalized FiF1　Appearance of vehicle earth stationFiF2The route for measurement in Shikoku-Kinki area (Beacon signal power)LongitudeLatitudeReceived power[dB]FiF3The route for measurement in Kyushu area (Beacon signal power)LongitudeLatitudeReceived power[dB]KanoyaKagoshimaIzumiOitaFiF4The route for measurement in West Japan facing the Sea of Japan (Beacon signal power)LongitudeLatitudeReceived power[dB]3 Ultra-High-Speed Satellite Communication Technology160　　　Journal of the National Institute of Information and Communications Technology Vol. 64 No. 2 (2017)