This paper proposes a satellite TV broadcast service system for the Asian and Oceanian regions, not as an alternative overseas satellite broadcast system to existing terrestrial overseas broadcasting systems, but as a system in which each country would have its own broadcast programs. First, the meaning of satellite broadcasting for developing countries and study examples are described. Second, the present broadcasting situation in the Asian and Oceanian regions is surveyed and analyzed, in conjunction with the size of population and national incomes in various countries. Third, the necessity for a satellite broadcast system to countries either without a TV broadcasting system or only limited TV broadcasting hours or having the insufficient penetration of TV sets is discussed. Fourth, the possibility of establishing a satellite broadcast system is studied. The broadcast countries are supposed to be 7 countries in the Asian region and 8 countries in the Oceanian region. The following system parameters are examined. Reception system: Community reception. Frequency band: 14/12.5 GHz band. Satellite geostationary location: 125 degrees east longitude. Finally, the parameters of a broadcast satellite, AOSAT, is presented.

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Japan Amateur Radio League, Inc, (JARL) supported by JARL′s Satellite Repeater Group (JAMSAT) is developing the first Japanese amateur radio satellite (JAS-1). JAS-1 is 26 faced polyhedron shape, about 40 cm by 40 m by 47 cm (16″ x 16″ x 19″) in size and 50 kg (110 Ibs.) in weight. JAS-1, which uses 145 MHz band for uplink and 435 MHz band for downlink, has two transponders each for analog and digital communications for world-wide amateur radio. These onboard transponders were manufactured by JAMSAT. JAS-1 will be launched in February 1986 by H-I test rocket of National Space Development Agency of Japan (NASDA).

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The purposes and performance characteristics of various experiments installed on Engineering Test Satellite-V (ETS-V) are described. The primary experiment is a mobile communication payload named “Aeronautical & Maritime Communication Experiment”(AMEX) consisting of L-band and C-band channels, to provide communication links for aircrafts and ships. In addition, several fundamental bus technology experiments such as RAM soft error monitor, solar cell degradation monitor and solar array vibration damping monitor are provided as “Technical Data Acquisition Equipment” (TEDA). Most of bus subsystems design have been derived from recent R&D activities sponsored by NASDA, and the operation of these subsystems is also the major experiment to verify the equipment performances to be used as the standard bus for spacecrafts planned in coming 10 years. It is anticipated that ETS-V will play the role of frontier for Japanese 3-axis controlled large geostationary communication satellites technology development.

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The H-II rocket is the second generation of Japan’s H series launch vehicles. The new rocket will provide a capability of launching a two ton class geostationary satellite (nearly 4 ton in a geostationary transfer orbit) in order to meet Japan’s needs in the 1990s. In the design and development of H-II, we aim at reducing its operational cost to the same level as the other major launch vehicles’ in the world. A survey on the prices of launch services of the Ariane launcher, the space shuttle, etc. shows that 17,000 - 21,000 dollars a kilogram of geostationary transfer orbit insertion may be the actual operational cost of this size of advanced launch vehicles. In the early stage of H-II system design, extensive trade-off studies on candidate subsystems were made, introducing a special index which is a function of launch capability, development cost, operational cost and number of vehicles flown. This index indicates a degree of cost effectiveness between cost and performance. It provided useful information for configuring the vehicle. As an example of studies with this index, first stage LOX tank pressurization systems, a gas oxygen pressurization system and a helium gas pressurization system, are discussed in this paper.

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