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1ntroductionAt the time of a large-scale disaster, information and communication technology provides essential tools for grasping situations and collecting information on disaster stricken areas, and for sharing information in rescue op-erations. Even in the case where terrestrial communication systems are severely disabled, satellite communication can provide an alternative communication. NICT has been conducting research on a high-speed internet satellite called WINDS (Wideband InterNetworking engineering test and Demonstration Satellite)[1]. e project includes the development and operation of an earth station mounted on a van called a vehicle earth station. e ve-hicle earth station is equipped with an antenna system capable of automatically detecting, tracking, and commu-nicating with the WINDS satellite while it is running[2].Understanding for the propagation environment is an important factor when constructing a communication system. NICT has conducted communication propagation measurements between a satellite and earth station on the moving vehicle earth station. Bearing in mind the future occurrence of a Nankai Trough Earthquake and associated giant tsunami, certain areas with higher possibilities of disaster damage were selected for extensive study: the wide Shikoku-Kinki area on the Pacic coast[3], Kyushu[4], and West Japan on the coast of the Japan Sea[5]. is report describes the results of the propagation measurement conducted moving around dierent areas. e study in-cluded up and down-link margin measurement of satellite links in a stationary state, the results of which are also described.2WINDS vehicle earth statione specications of the vehicle earth station are listed in Table 1, and its appearance is shown in Fig. 1. e ve-hicle earth station consists of such elements as a radome antenna (cassegrain antenna with a diameter of 65 cm), a 20W-class high power amplier (HPA), a 3-axis gimbal mechanism, modulator and demodulator. As shown in Tx frequency27.5-28.6 GHzRx frequency17.7-18.8 GHz18.9 GHz (for receiving beacon)Polarized waveLinearly-polarized wave (V/H)SSPA output20 WEIRP55.5 dBWG/T16.0 dB/KAntennaCassegrain antennaDiameter: 65 cmAntenna driving rangeEl: 20-90 degAz: endless rotationX-El: ± 15 degTracking accuracy<± 0.2 degData rateRegenerative modeTx: 1.5, 6, 24, 51 MbpsRx: 155 MbpsUser interfaceEthernet (1000 base-T)Power generation capacity≧ 2.8 kVATabT1　Specifications of the vehicle earth station3-11 A Measurement of Propagation in High Mobility Environments for Ka Band Satellite CommunicationTomoshige KAN, Akira AKAISHI, Byong-pyo JEONG, Kazuyoshi KAWASAKI, Toshio ASAI, and Takashi TAKAHASHISatellite communication has attracted attention as an effective means of communication in an emergency such as a disaster. National Institute of Information and Communications Technology (NICT) has developed a small-vehicle stations equipped with the antenna system for automatic tracking for the Wideband InterNetworking engineering test and Demonstration Satellite “KIZUNA” (WINDS), it has become possible to build a satellite line while moving. In this study, we report radio wave propagation measurements assuming the Nankai Trough earthquake in Ka-band satellite communications under a fast-moving environment in Shikoku and Kinki area, Kyusyu area, and the Coast of japan sea of western Japan.1593 Ultra-High-Speed Satellite Communication Technology