Site: Ministry of Posts and Telecommunications (MPT)
Space Communications Policy Bureau
0-2 Kasumigaseki
1 Chome Chiyoda-ku
Tokyo 100-90, Japan

Date Visited: October 22, 1992

Report Author: J. Pelton



J. Pelton
M. DeHaemer
M. Miyahara (NSF Tokyo Office)


Masaaki Notsu

Deputy Director, Space Communications Policy Division

Yuji Okada

Deputy Director, Space Communications Policy Division

Yukio Nishiuehara

Chief, International Affairs Section, Space
Communications Policy Division


MPT is the national governmental agency that defines and funds R&D projects in the space communications area. In this respect it has been the lead agency, in conjunction with NASDA, for CS, CS-2, and CS-3 (1988). There is now a new approach to government-supported development. In 1995, for instance, there will be a need for a new satellite system to replace CS-3. This is being carried out as a private satellite development project rather than a MPT/NASDA project, in the form of the N-STAR satellite system being built by SS/Loral with the major Japanese subcontractor being NEC.

This change is in part a result of a "satellite arrangement" made by a trade committee with the U.S. concerning non-R&D satellites. Under this satellite arrangement, the government of Japan has adopted open, transparent and non-discriminatory policies and procedures for the procurement of non-R&D satellites by or for the use of the government of Japan and related entities (e.g., NTT's N-STAR). The MPT is thus now initiating programs only for R&D. COMETS, which is to be launched in February 1997, is the most significant project under the new satellite arrangement. ETS-VI was started before the satellite arrangement was signed, but does not really involve commercial service in any event. The only remaining activities are small, clearly experimental projects. MPT, in response to written questions submitted in advance of the visit, noted that there were many ways in which the Japanese Government fostered the positive development of space communications (e.g., through tax incentives, low interest loans, etc.). These are discussed more in depth in the policy section of this report (Chapter 1). MPT also described in some detail how the annual Space Development Plan is coordinated with relevant government agencies and ultimately reviewed and approved through the Prime Minister's office. This is described in greater detail in the policy section.


MPT's R&D Activities

MPT carries out a wide range of R&D activities. The areas discussed included the following:

Fiber Optic Cable Competition with Satellite Communications. MPT intends to keep its options open. Cost equations do not definitively resolve exactly which applications and services are best suited for space vs. terrestrial communications. Nevertheless, at this date, satellites seem to have their greatest strengths in mobile, rural, and broadcasting applications. Some trunking and restoration services seem possible into the future. New satellite applications may prove possible at higher frequencies with effort by the MPT's CRL focussing on 46/43 GHz and 30/20 GHz.

The ETS Series of Experimental Satellites and the Transition to Commercial Programs. ETS-V was launched in August 1987 by H-I rocket; ETS-VI and VII are to be launched in 1994 and 1997, respectively, by H-II rocket. The problems with the H-II launch vehicle have prevented this experimental series from being completed early. The object is to convert under the U.S. satellite arrangement to a commercial satellite project. New experimental projects in optical communications, small satellite systems, DBR or other innovative areas may still be started. The deregulation and restructuring of the Japanese telecommunications industry has already led to more U.S. participation (by LORAL, Hughes and GE). Hughes is even a partner in one of the new common carriers for satellite communications. These are as described below:

Radio Broadcast Satellites. MPT has a great interest in the feasibility of DBR and has commissioned studies in this area. There are no developmental satellite programs in this area at this time.

Direct Broadcast Satellites. The BS-3a and -3b are the last NASDA R&D and practical use satellites in the direct broadcasting area. Although MPT closely monitors this field, it is considered essentially commercialized. There are some 6.37 million DBS subscribers in Japan as of the end of September 1992. The current status of satellites is as follows:

The feasibility of converting to digital service and thus deriving two television channels per transponder is under active study. In 1997 there will be a need for a new DBS satellite system to replace the BS-3 series. This project will be entirely a private sector enterprise.

The status of home DBS antennas for TV reception was also reviewed. The price of flat plate antennas was discussed. It currently ranges from $1,000 to $1,200 while more conventional parabolic type receivers range from about $400 to $600. The prices of both types of antennas continue to drop.

Next 10 Years

The trend over the past 10 years has clearly been toward bigger satellites in orbit. There is some doubt as to whether this will be the trend for the next decade. There is some thought that small, cost effective, reliable, high quality satellites could play key roles in the future. Furthermore, LEO and MEO satellites arranged in global constellations could redefine the purpose, capacity, and performance of satellite systems. Certainly the low delay, high elevation angle and small terminals that can be achieved with lower earth orbit systems seem very attractive. The drive to achieve new economies and cost competitiveness with fiber optic cable may be a key driver in the future development of satellite systems. Also, hybrid satellite systems that combine terrestrial and space communications systems in new and innovative ways may be among the keys to the future.

Published: July 1993; WTEC Hyper-Librarian