Data relay system concept for Japan

Abstract

1.2 International Cooperation of Space It is anticipated that in the future Network Int_er~tional Cooperation at many kinds of spacecraft such as earth SNIP observation satellites, space stations, To establish the Space Network and space planes will be launched. system, NASA has materialized a tracking To collect data from the spacecraft and data relay satellite system, and ESA efficiently and support their various space activities, NASDA has planned the development of space nework ground system using data relay satellites. The use of data relay satellite on the geostationary orbit will make it possible to achieve high data rate communication from the spacecraft and continuous real time spacecraft operation. This paper describes the space network ground system concept for future space infrastructure below. 1) Development plan of NASDA Space Network system 2) ETS-VI experimental ground system design 3) New service possibility for future space activites 1. PROSPECTS FOR DEVELOPMENT AND IMPROVEMENT OF SPACE NETWORK SYSTEM 1.1 NASDA Development Plan of Space Network System NASDA plans to develop and improve the Space Network system, including preliminary experiments required for development. This is because the existing tracking and control system needs to be upgraded and a new operating system using a data relay and tracking system will be required to ensure the high-level operation of spacecraft launched by the H-11 rocket and of JEM. In the Space Network Plan, the following experiments will be performed to develop and improve a future comrnunications network system mainly composed of the data relay and tracking satellite as shown in Fig. 1. NASDA plans to develop and improve a data relay and tracking satellite thrcugh experiments with ETS-VI and COMETS. On the assumption that the user satellite is an earth observation satellite which must transmit high data rate and receive data from all over the world, or a space station which is expected to perform continuous data transmission and TV picture transmission, NASDA intends to perform experiments using ADEOS and JEM for the time being. Copyright @ 1992 American Institute of Aeronautics and Astronautics, Inc. All rights reserved. and NASDA are studying the design of DKS and DRTS. In parallel with efforts to construct the Space Network system, NASA, ESA, and NASDA have been studying the possibility of international space network interoperability in terms of technical standards. The recommendations on the S band (technical recommendations from the representatives of NASA, ESA, and NASDA) prep~red last year led to the materialization of plans for technical verification tests by experiments conducted between NASA and NASDA and between NASA and ESA. In addition, a study of recommendations 0 1 1 the K band was also commerlced. 1.3 Future Experimental Plan of NASDA -(I) ETS-VI Space Network test Intersatellite corrmunication tests equipment will be carried on ETS-VI and experiments (maximum data signaling rate: approx. 3 Mbps) will be performed between a durmy satellite and ADEOS to acquire the basic equipment technology and operation technology required to construct and operate the Space Network system. Arrangements with the orqanj zztions concerned are being made with a view to performing the experiment (SNIP verifjcation tests) on S-band interoperability between NASDA and NASA for the purpose of international cooperation in iriteroperation, and procedures for the experiment are being established. ( 2 ) CONETS space Network test Experiments with COMETS and two-way communications experiments (maximum data signaling ratc: approx. 120 Mbps) will be performed to establish the basic equipment technology and operation technology required to construct and operate the Space Network system. The Ka-band interoperability experiment will be carried out between NASDA arid ESA and S-baud interoperability will be performed between NASDA and both ESA and NASA for the purpose of international cooperation. Around 1993 Around 1997 Around 1999