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This paper describes the research and development on the personal satell i te communications system using the millimeter-wave and Ka-band in Japan, focusing on the Communications Research Laboratory(CRL)'s projects through the Engineering Test Satellite VI (ETS-VI) and Communications and Broadcasting Engineering Test Satellite (COMETS) projects. Both satellites have been mainly developed by National Space Development Agency (NASDA), and CRL has developed experimental communication payloads to carry out the personal satellite communications experiment. Those payloads employ millimeter-wave band and Ka-band to provide large capacity to networks. In the ETS-VI projects, the basic technologies to utilize millimeter-wave and Ka-band such as devices and satellite access protocols will be developed. Subsequently, active phased array antenna, onboard switching technology and network management technologies will be developed through COMETS project. The ETS-VI and the COMETS will be launched in mid 1994 and early 1997, respectively. |
