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5Concluding remarksExperiments with the mobile earth station were made to evaluate the propagation characteristics and up-link and down-link margin using the Ka-band satellite communica-tion system. e data obtained from this experiment con-rmed that the mobile earth station is able to capture the satellite above even it is moving at high speed. e ratio of the sections with a visible environment (i.e. the satellite can be captured in line of sight) over the entire length covered by the experiment was about 70% in the Shikoku-Kinki area, and about 80% in Kyushu and West Japan along the coast of the Sea of Japan. And then, tunnels were the dominant factor that hinders line-of-sight visibility.Measurements of received C/N0 of the reference burst signal from the MBA showed agreement between the measured and theoretical values (within ±1 dB).Measurements of Doppler frequency also showed agreement with the theoretical value, conrming the valid-ity of the link design approach that uses the maximum measured Doppler frequency corrected in consideration of the moving velocity of the earth station.From the link margin values obtained, we can conrm the feasibility of 24 Mbps mode communication in all measured areas in the experiment. Although there are some elements that hinder satellite visibility, their eects are only transient except tunnels. Taking all factors into consideration, the results from all measured areas proved that satellite communication will be of great use at the time of a disaster.ReferenceR1Special Issue on Wideband InterNetworking engineering test and Demonstration Satellite (WINDS), Journal of the National Institute of Information and Communications Technology, vol.54, no.4, Dec. 2007.2Akira AKAISHI, Takashi TAKAHASHI, Mitsugu OHKAWA, Toshio ASAI, and Byeongpyo JEONG, “Ka-band Mobile Earth Station for WINDS,” 29th ISTS, June 20133Tomoshige Kan, Takashi Takahashi, Kazuyoshi Kawasaki, Akira Akaishi, Toshio Asai, Byongpyo Jeong, Hajime Susukita, Shuji Murakami, and Morio Toyoshima, “A Measurement of Propagation in High Mobility Environments for Ka Band Satellite Communication,” IEICE technical report, vol.115, no.287, SAT2015-62, pp.79–84, Nov. 2015. (in Japanese)4Tomoshige Kan, Akira Akaishi, Toshio Asai, Takashi Takahashi, Kazuyoshi Kawasaki, Byongpyo Jeong, Hajime Susukita, Shuji Murakami, and Morio Toyoshima, “Propagation Measurement for Mobile Satellite Communications Using WINDS at Kyushu Area,” Proceedings of the 2016 IEICE General Conference, B-3-16, March 2016. (in Japanese)5Tomoshige Kan, Takashi Takahashi, Kazuyoshi Kawasaki, Akira Akaishi, Toshio Asai, Byongpyo Jeong, Hajime Susukita, and Morio Toyoshima, “Propagation Measurement for Mobile Satellite Communications Using WINDS at The Coast of Japan Sea of Western Japan,” IEICE technical report, vol.116, no.470, SAT2016-75, pp.81–86, Feb. 2017 (in Japanese) 6https://iperf.fr/7Satoru OZAWA, Masaaki SHIMADA, Yasuo Nakamura, Yoichi KOISHI, Satoshi KUSAMA, Katsunori HIRAYAMA, Ken MAEDA, and Keita FUKUHARA, “Multibeam Antenna System of WINDS Communication Satellite In-Orbit Performance Test Results,” Proceedings of the Space Sciences and Technology Conference, vol. 52, pp. ROMBUNNO.1A09, 2008.Tomoshige KAN, Dr. Eng.Researcher, Space Communications Laboratory, Wireless Networks Research CenterSatellite communication propagationAkira AKAISHI Space Communications Laboratory, Wireless Networks Research CenterSatellite communications systemByong-pyo JEONG, Dr. Eng.Senior Researcher, Applications Laboratory, Resilient ICT Research CenterDisaster response, GIS Satellite communicationKazuyoshi KAWASAKI Senior Researcher, Space Communications Laboratory, Wireless Networks Research CenterSatellite communicationToshio ASAI Space Communications Laboratory, Wireless Networks Research CenterSatellite communications systemTakashi TAKAHASHI Associate Director, Space Communications Laboratory, Wireless Networks Research CenterSatellite communication1653-11 A Measurement of Propagation in High Mobility Environments for Ka Band Satellite Communication