Basic Studies for Space Solar Power Systems in Japan

A Space Solar Power System (SSPS) comprises many parts, in a space segment and a ground segment. In order to construct an SSPS, many parts have to be launched to space using rocket vehicles. All these subsystems must complete a phase of basic research, before starting the development phase. This paper presents the basic SSPS research in Japan on selected topics. Spacetenna construction is discussed from both viewpoints of mechanical structure and electrical performance. Beam-forming using phased array antennas is explained. For launch, a new type of microwave rocket is introduced. The details and present achievements of each topic are written by a representative of each research group.