Tsutomu Shigeta, Takashi Miyoshi
Satellite Mission Application Center, Office of
Satellite Systems,National Space Development Agency of Japan (NASDA)
2-1-1 Sengen, Tsukuba-shi, Ibaraki 305-8505, Japan
TEL: +81-298-59-2987, FAX: +81-298-50-1916 e-mail: firstname.lastname@example.org
While NASDA has been engaged in the development of new satellite missions and the bus technologies, NASDA explores new and attractive applications by promoting the utilization of satellite missions and strengthening the relationships with external parties. Offering opportunities to external parties for conducting application experiments will bring great chances for them in challenging and experimenting new space-based applications. Consequently, it is expected that the outcomes of the space development are returned to general public, research institutes, industries, and that ideas or requirements for new satellite mission could emerge and be materialized. With these objectives in mind, NASDA is presently planning a new space project that is named "i-Space". The i-Space project aims to contribute to the progressing "IT Revolution" by providing new space communication capabilities and to develop practical applications by collaborating with external parties. This paper introduces the activities and roles of NASDA in promoting satellite utilization experiments, particularly focusing on the i-Space project.
Keywords: Satellite; IT, I-Space
NASDA newly established the Satellite Mission Application Center, in its
Office of Satellite Systems, in order to strengthen NASDA's activities, in the
fields of communications, broadcasting and navigation, for creating new
satellite missions and promoting utilization of the space-based technologies.
As shown in Figure-1, which shows the lifecycle of the satellite mission, an important role of the Center is to strengthen the upper part of the cycle, namely the mission utilization and the mission planning. Promoting utilization of the space technologies and reflecting utulization results to the mission planning could create new and attractive satellite missions.
The Center acts as a focal point of NASDA in coordinating cooperative activities with domestic and overseas institutions for the above-mentioned activities.
2.1. Outline of the "i-Space" project
In recognizing the importance of advanced information society, the Japanese
Government is encouraging the government-affiliated organizations to create
effective measures for coping with the emerging new era of "IT(Information
Technology) Revolution", presently one of the major political agenda. In
response to such a social demand, NASDA is proposing a new space project named
"i-Space" so as to contribute to the revolutionized information
society by developing new space-based communication capabilities which is to be
effectively integrated with the ground communication infrastructure, as well as
conducting demonstration experiments in a variety of application areas.
One important objective of the "i-Space" is to effectively utilize newly-developing satellite communication technologies, including the satellite-based Internet system and the mobile communications, for coping with national issues such as Earth environment, education, medical treatment, security management, etc. By demonstrating the usefulness of such new capabilities and their advantages over the terrestrial communications, the i-Space project will serve as a bridge to the future operational use of space communications in many application fields. (See Figure-2)
Another important objective is to contribute to the issue of "Digital Divide". While the advanced multimedia technologies and communication systems have been remarkably and rapidly advanced these days, however, a gap in the information environment available for person is expanding because of several reasons including the geographical differences. Since the satellite can quickly offer a high data-rate communication environment over a wide area, it will exactly make it possible to build an information infrastructure overcoming the geographical disadvantage. The i-Space project aims to solve the digital divide problem not only in Japan but also in the Asia-Pacific region.
2.2. Satellites utilized for the i-Space project
Under the i-Space project, NASDA is proposing conducting several application
experiments, utilizing different types of satellites. As the first step of the
project, NASDA conducts pilot experiments utilizing existing commercial
satellites as a precursor testing for the later-mentioned developing satellites.
In the next phase, the advanced satellite mobile communications and its
application systems will be demonstrated utilizing the Engineering Test
Satellite-VIII (ETS-VIII). Then as the next step, the High-data-rate Internet
Satellite system will establish important elements of the Internet-based
In addition to these satellites, NASDA is planning to make a system study on the Quasi-geostationary Satellite, which is the next generation's mobile communications satellite system.
These elements should be closely linked so as to promote their utilizations and to create new applications. The followings are the brief introduction to the ETS-VIII, the High-data-rate Internet Satellite and the Quasi-geostationary Satellite.
ETS-VIII is being developed for its launch in 2003 with the objectives of developing following technologies (See Figure-3):
a. The world's largest 3-ton class geo-stationary satellite bus, and a large-scale deployable antenna of greater than 13m
b. Cost-effective communications services with hand-held terminals for mobile-to-mobile audio and data communications
c. Mobile digital multimedia broadcasting with CD quality, and image transmission system
d. High precision clock system for satellite positioning experiments
ETS-VIII is expected to be in use for both domestic users and neighboring
countries for several years after its initial tests. The S-band mission antenna
of ETS-VIII is primarily designed for covering the Japanese archipelago,
however, NASDA is considering extending its coverage by controlling the
satellite's attitude. The recent study shows that the coverage may be extended
to the Philippines, Vietnam, China, and so on.
It is under coordination that the ETS-VIII utilization experiment will be announced by releasing the Announcement of Opportunity (A.O.). NASDA is studying the A.O. conditions and an experiment-planning scheme by interviewing many potential users through the after-mentioned survey and the user community.
ii) High-data-rate Internet Satellite
The experimental "Gigabit-class" communications satellite is currently being studied by the Communications Research Laboratory (CRL) of the Ministry of Posts and Telecommunications (MPT) together with NASDA, to develop and introduce the advanced satellite communications technologies which are essential to ushering in the optical fiber network era, and to demonstrate the applicability of the satellite-based Internet services. The satellite is capable of providing services as fiber-like Gbps trunking connection and the 155Mbps ATM-based multimedia access by small-aperture terminals throughout the Asia-Pacific area.
Even though the high-speed terrestrial lines such as optical fiber networks are being laid, the satellite communication system can be utilized as a complementary system together with ground infrastructure. The satellite multicasting function (one to N communication) is one of its significant features making use of its wide area coverage and simultaneity.
iii) Quasi-geostationary Satellite System
Table-1: Examples of the ETS-VIII experiments proposals
No. Experiments themes
1 Mobile medical care for remote areas and in emergency cases
2 Educational usage for the field class on the theme of environmental issues
3 Image data transmission for improving efficiency of the Remote-Sensing ground truth activities
4 Sea-surface data in-situ measurement and transmission experiment
5 Application for forest site management and reporting
6 Monitoring network for volcanic ashes and flood problems
7 Forest-fire early warning and damage assessment system using Remote-Sensing satellite data
8 S-band digital mobile broadcasting experiment
9 Precise ETS-VIII orbit determination and clock synchronization using GPS-like navigation signals
10 Measurement of propagation delay and ionosphere/troposphere layer elects on L-band and S-band
By placing three satellites in the inclined three orbits of the same size of
the geo-stationary orbit, keeping the same intervals among three satellites,
either of the satellites is always kept in a position directory above the
Japanese archipelago, and accessible with high elevation angle. (See Figure-5)
Because of the following features, the system is suitable for mobile communications, particularly in urban areas.
1) Reduction of building blockade
2) Effective utilization of satellite orbit and frequency
3) Usefulness for positioning function
2.3. Examples of the i-Space experiments
Figure-6, Figure-7, and Figure-8 shows examples of the applications which the i-Space may realize. In these figures, the High-data-rate Internet Satellite and ETS-VIII are usefully utilized, taking advantages of their features and capabilities, namely, the high-speed communications, the satellite-based Internet services and the mobile ability.
For promoting utilization of the space-based technologies, NASDA is intending
to play active roles for the purpose of returning back the outcome of the space
developments to the society. NASDA is now planning some satellite utilization
experiments aiming to explore attractive satellite-based applications, and is
presently engaged in the followings;
1) Conducting the survey on ideas for utilization of ETS-VIII and the High-data-rate Internet Satellite
2) Organizing satellite briefing sessions and the International Forum (MPT as the main organizer)
3) Preparing for the utilization experiments of ETS-VIII and the High-data-rate Internet Satellite
4) Planning and conducting the pilot experiments utilizing commercial communications satellite
5) Organizing the user community on satellite utilization
Regarding the above item 1), NASDA has been conducting a preliminary survey for both domestic and overseas institutions in the Asia-Pacific region to receive experiment proposals for ETS-VIII and the High-data-rate Internet Satellite, by providing technical information and arranging technical briefing sessions. Many attractive ideas have been proposed with the number of around 100. NASDA is presently communicating with proponents to shape up the significant ideas for possible future implementation of the experiments.
As Table-1 shows typical examples of the ETS-VIII usage which are picked up from the survey result, many of the expectations to the ETS-VIII are the two-way transmission of multi-media data including video, voice and PC connection at locations where terrestrial communications are not available or sufficient. From this survey result, it could be said that the ETS-VIII utilization concept is a "Multimedia at anywhere & anytime".
For participating in the ETS-VIII
experiments, each participant principally needs to prepare necessary ground facilities including the S-band communications terminal and the application equipment. However, since the S-band terminal is not available on the market, NASDA is considering trial manufacture, and providing the terminals to experiment users. (See Figure-9)
As for the High-data-rate Internet Satellite, many of the expectations to the satellite are, as shown in Table-2, for the use of multimedia technologies for variety of application areas such as medical, education, and its application for supercomputer networking, establishment of Earth observation network and the forest fire management. From this survey result, it could be said that a concept of the High-data-rate Internet Satellite utilization is a "High-speed Multimedia Networking".
Table-1 Examples of the ETS-VIII experiments proposals
|1||Mobile medical care for remote areas and in emergency cases|
|2||Educational usage for the field class on the theme of environmental issues|
|3||Image data transmission for improving efficiency of the Remote-Sensing ground truth activities|
|4||Sea-surface data in-situ measurement and transmission experiment|
|5||Application for forest site management and reporting|
|6||Monitoring network for volcanic ashes and flood problems|
|7||Forest-fire early warning and damage assessment system using Remote-Sensing satellite data|
|8||S-band digital mobile broadcasting experiment|
|9||Precise ETS-VIII orbit determination and clock synchronization using GPS-like navigation signals|
|10||Measurement of propagation delay and ionosphere/troposphere layer elects on L-band and S-band|
Table-2: Examples of the High-data-rata Internet Satellite experiments proposals
|1||Evaluation of TDM effectiveness for global TV broadcasting|
|2||High speed interactive database access via asymmetrical communication link|
|3||Developing small aperture terminal for multimedia data transmission with QoS requirement|
|4||Forest fire monitoring and management utilizing Remote Sensing data|
|5||Parallel processing of super computers|
|6||Establishing virtual LAN services through the High-data-rate Internet Satellite network|
|7||QoS evaluation for the High-data-rate Internet Satellite network|
|8||Multi-media video conferencing for environmental awareness|
|9||Online Workshop for local communities|
|10||Establishing Community Tele-service Center (CTC) for rural development issues|
NASDA is planning to conduct some pilot experiments, utilizing commercial
communications satellite as a precursor testing for ETS-VIII and the
High-data-rate Internet Satellite.
The pilot experiments are to be conducted in both domestic and neighboring countries, and the experiment themes and collaborative partners would be decided taking into account the significance of the experiments, such as social impacts and contribution to domestic and regional issues, as well as feasibility including cost and the partner's resources.
As for the schedule, NASDA is intending to initiate some experiments from early 2001 for ETS-VIII, and also considering conducting some experiment themes for the High-data-rate Internet Satellites.
Introduced hereafter are two pilot experiment themes, which are to be conducted for the preparation of ETS-VIII utilization experiments.
4.1. Medical use:
In the medical field, satellite has a great potential for its applications
and may help expand doctors' activities. A medical doctor used to bring his/her
medical bag to the patient's home, accident place, rural hospital, however, the
medical bag might be replaced by the ETS-VIII communications terminal by which
doctor or nurse can access to;
1) Patient clinical record that is databased in the main hospital
2) Doctor at big hospital for expert consultation
The pilot experiment aims to realize the above concept and, thus, pursue
technical challenges necessary for realizing them.
One of the possible applications of the pilot experiment is the mobile medical van, which goes to rural areas where a basic communications infrastructure and medical facility are not sufficiently provided. This might be useful, in particular, for the rural areas in the Asia-Pacific region.
4.2. Educational use:
The experiment theme is entitled "Satellite-based field education on the
theme topic of environmental issues". NASDA is looking at the potentiality
of the satellite-based mobile communications and the Earth observation satellite
data for activating the education program dealing with environmental issues.
Utilizing the mobile communications satellite such as ETS-VIII, a class room in school will be connected with a teacher outside, for example, in coastal zone with issue of environmental damage, where no communication infrastructure is available. In such a place, the mobile-type satellite-based TV conference system make it possible that teacher outside and students in the classroom discuss on environmental problems looking at the real image of the site on the TV conference system. As a main theme of the education program is for environmental issues, the satellite Earth observation data will be effectively utilized.
This satellite-based education tool is also useful for giving lessons from temples, ruins, and any places where terrestrial communication is not available.
For promoting utilization of satellite communications, NASDA considers it
also important to strengthen its relation with external parties and consult with
many potential users in various fields.
NASDA is organizing the User Community on Satellite Utilization consisting of members from industrial sector, universities, research institutions, etc. The Community aims to provide forum for many experts in various fields to discuss on satellite utilization, new satellite missions and social needs in the area of communications, broadcasting and navigation.
As introduced above, NASDA is exploring cooperative activities with domestic
and overseas partners, with the Satellite Mission Application Center as a focal
point of NASDA.
For the successful implementation of the satellite utilization experiments, active participation from various application fields, as well as organizing user communities, is important. In this regard, NASDA will try to continue its cooperation with domestic and overseas institutions, in the hope that NASDA may provide the opportunities of satellite utilization.
NASDA wishes to invite ideas for the application experiments utilizing ETS-VIII, the High-data-rate Internet Satellite as well as ideas for the pilot experiments.
Fig.1 Role of the Center in the satellite mission cycle
Fig 2 Image of the i-Space Project
Fig 3 Image of ETS-VIII
Fig 4 High-data-rate Internet Satelllite
Fig 5 Quasi-geostationary Satellite System
Fig 6 Example of the i-Space Experiments (Application to education field)
Fig 7 Example of the i-Space Experiments (Application to medical field)
Fig 8 Example of the i-Space Experiments (Application to disaster management field)
Fig 9 Image of the ETS-VIII utilization