1998 Fiscal Year Final Research Report Summary
Study of a limit in the Space Collaboration System
| Project/Area Number |
09680234
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Educational technology
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| Research Institution | National Institute of Multimedia Education |
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Principal Investigator |
ASAI Kikuo RESEARCH & DEVELOPMENT RESEARCH ASSOCIATE, 研究開発部, 助手 (90290874)
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| Co-Investigator(Kenkyū-buntansha) |
TANAKA Kenji MINISTRY OF POSTS AND TELECOMMUNICATIONS COMMUNICATION RESEAARCH LABORATORY COMM, 通信システム部, 研究官
HAYASHI Zenzi RESEARCH & DEVELOPMENT ASSOCIATE PROFESSOR, 研究開発部, 助教授
YUKI Kiyohiro RESEARCH & DEVELOPMENT PROFESSOR, 研究開発部, 教授
OHNISHI Hitoshi RESEARCH & DEVELOPMENT RESEARCH ASSOCIATE, 研究開発部, 助手
KONDO Kimio RESEARCH & DEVELOPMENT PROFESSOR, 研究開発部, 教授
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| Project Period (FY) |
1997 – 1998
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| Keywords | Educational Exchange Network / VSAT / Rain Attenuation / Remote Use / Link Control / Audio-Video distribution |
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| Research Abstract |
To make stability and extension of operation on the inter-university satellite network (Space Collaboration System : SCS), we provide specification limit of the system control equipment and propose specification of the extension. The measurement of switching time of transmitting station shows the operation with the present VSAT number switching them Within 6.5 sec. The communication signal is controlled with slotted aloha method, and the timing is arranged not to collide the burst signals for controlling carriers. Increasing participant stations causes problems in starting the session. At the time, the session information is transferred from a HUB station to VSAT stations. Increasing the stations requires much time to send the data, and it causes delay of the staffing time. One of solution for this problem is to add in-band to the present system.
Rain attenuation characteristic is measured by receiving a satellite beacon signal to check effect for link quality due to the rain attenuatio
… More
ns. We observed power attenuation of 2dB for 0.25mm/m. But it is expected that the rain attenuation does not cause disabled things with margin over 10dB on AGO by receiving a satellite telemetry signal.
The primary requirement of the SOS extension is remote operation. This is based on the reason that Each campus has only one VSAT station in the university, and the SOS facilities have been installed usually in a lecture room or meeting room because of lack of space. This situation has caused collision of reservations for the room shared by the SCS, so the SOS could not be used very often even though the transponder channel was available. To solve this problem required a remote operation by using the SOS in a different room from where it was installed, This was accomplished by the transfer of audio and video signals and the remote control of the channel control system. We discuss three methods of the remote link control : (l)Touch Panel Method, (2) Window-Share Method, (3) WWW Method. We selected the WWW Method due to the extensity and flexibility, and installed it to the SOS.Distribution of audio and video need reasonable choice of media for the present equipment and required quality, such as coaxial cable, optical fiber, wireless system, and ISDN.We evaluated the usability of remote operation of the SOS in the international forum. Less
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