Site: NASDA Tsukuba Space CenterPRIVATE
2-1-1 Sengen Tsukuba-Shi
Ibaraki-Ken 305
Japan

Date Visited: October 19, 1992

Report Author: J. Pelton

ATTENDEES

NASA/NSF:

W. Brandon
M. DeHaemer
R. DePaula
C. Mahle
E. Miller
J. Pelton
A. Chang (Visiting Intern to NASDA from JPL)

HOSTS:

Hidetoshi Murayama

Director NASDA Tsukuba Space Center

Noboru Takata

Asst. Senior Engineer

Hideo Hara

Asst. Senior Engineer

Saburo Kuwajima

Communications Equipment Lab, Engineer

Toshio Doura

Asst. Senior Engineer

Masaaki Shimada

Asst. Senior Engineer

BACKGROUND

The NASDA Tsukuba Space Center, established in 1972, has grown over the last 20 years to be a major center for research in launcher development, test and integration, and satellite operations (tracking, telemetry and command) in the field of satellite telecommunications. NASDA Space Center at Tsukuba has an annual budget of $450 million. It supports a wide range of technologies through contractor studies. 120 NASDA employees plus contractor personnel work on R&D activities. NASDA usually contracts its satellite communications research work to industry, while CRL and ATR provide governmental technical leadership.

Despite impressive test and integration facilities of world class quality (e.g., 13 m(superscript 3) thermal vacuum space chamber, 1600 m(superscript 3) acoustical test facility), Tsukuba Space Center has a relatively small staff of 250 NASDA professional employees plus 100 to 150 contractor personnel. Projects at the center include the H-I and H-II launch vehicles now completed and the J-1 launcher. Experimental satellite projects include the ETS-VI and -VII spacecraft, COMETS, ERS-1 and -2 and the Japanese Experimental Module (JEM) for the U.S. Space Station Freedom, the ADEOS Observation Program, and the HOPE reusable space shuttle that will be mated with the H-II launcher. Much of the design, manufacturing, test and integration of experimental communications satellites is left to the contractor and subcontractor organizations, typically NEC, MELCO and Toshiba.

Clearly, NASDA provides overall leadership in Japan's effort to develop new space technology. NASDA, in cooperation with CRL, ATR, ISAS and Japanese aerospace industry, especially the big three listed above, design new spacecraft, develop new technology, implement experimental missions and conduct tests and evaluations of flight prototypes. Overall, this effort is well coordinated among the several governmental agencies and private corporations involved.

RESEARCH AND DEVELOPMENT ACTIVITIES

NASDA R&D

NASDA R&D includes, among others, the following:

Advanced, Highly Reliable Batteries. Development and life testing is being carried out with nickel hydrogen (NiH(subscript 2)), nickel-cadmium (NiCd) and nickel metal hydride (NiMH) batteries especially for small satellites. (Note: the most advanced battery work in Japan, in the area of lithium ion batteries is being conducted at Toshiba.)

Infrared Sensors. Coded devices in the 3 and 12 micron frequency range are being developed and tested.

Advanced Thrusters. Xenon ion thrusters have been developed by Toshiba and MELCO for use on ETS-VI and COMETS. There is no active research on hyperbolic fuels or hybrid systems, since these are not expected to produce significant new results in terms of lifetime or thrust performance.

Launch Research. Work is aimed primarily at developing the H-II and Hope launch vehicles, although the J-1 small launcher is under active development as well. No sea launch facility is currently under development. There are delays associated with development of the H-II launcher program, and there are concerns that the J-1 launcher will be too expensive ($25 to $35 million) to be internationally competitive. Methane-liquid oxygen-fueled boosters are also under study.

High Temperature Superconductivity. NASDA indicated that this area was not being pursued except for "paper studies" at this time, with the primary effort being at SRL (Dr. S. Tanaka), plus some work at NTT as well.

Optical Systems. The ETS-VI optical ISL uses a 7.5 cm telescope on-board the spacecraft. The ground optical telescope system implemented by CRL employs a 20 cm transmit facility and a 1.5 m receiving telescope.

Radiation Testing. The radiation test facility uses Cf 252 as its radiation source. All semiconductors for use on spacecraft are tested here. This includes all analog and digital components, SRDs, DRAMs, etc. This is a well equipped facility with a very comprehensive approach to testing.

LEO Satellite Systems. NASDA is actively sponsoring research on small satellite systems of the 100-500 kg class. NEC, Toshiba, MELCO and CRL have active study programs in this area and a program called OICETS will begin soon.

New Frequency Applications/Allocations. The COMETS 20/30 GHz mobile communications experiment is planned to study feasibility of future mobile services in these bands. The feasibility of using 43/38 GHz for PCS is being studied by CRL in an ETS-VI experiment.

Optical Communications Development. The small optical experimental satellite project (OICETS) is expected to obtain Phase B approval this year, allowing experiments with the European ARTEMIS project. The candidate optical equipment would be a 140 kg experimental package consuming 250 W.

Other Observations

Although not developed at NASDA, the tour included examination of the lightweight roll-out flexible solar array system (with 1/3 less mass) and the shaped (i.e., specially molded) antenna reflectors that will allow beam shaping to match the irregular shape of the Japanese islands "footprint" using only two feed horns on the BS-3 satellites.


Published: July 1993; WTEC Hyper-Librarian