Seiko Shirasaka
Small Synthetic Aperture
Radar Satellite System
for On-Demand Observation
Program Manager
Seiko Shirasaka
  • Program Offical HP
1994 Masters of Engineering from Graduate School of Engineering, the University of Tokyo
2012 Ph. D. in Systems Engineering from Graduate School of System Design and Management, Keio University
1994 ~ 2010 Mitsubishi Electric Corporation Kamakura Works
2000 ~ 2002 EADS Astrium (present name: Airbus) Exchange Engineer
2010 ~ Associate Professor, Graduate School of System Design and Management, Keio University
2015 ~ ImPACT Program Manager
2017 ~ Professor, Graduate School of System Design and Management, Keio University
Profile

What's New

Overview

During emergency situations such a natural or man-made disaster, rapid responses by social infrastructure are essential in order to minimize damage. “24 hours responsibility under all-weather condition”, “ quick response”, “responsibility for wide area disaster” and “ simultaneous observation capability for surrounding region” are surely required for the satellite observation system to be beneficial as reliable social infrastructure. This program develops Small Synthetic Aperture Radar (SAR) satellite system capable of on-demand launching and quick observation. The new approach of SAR design “Deployable and Passive Slot Array Antenna System” is selected in this program and it realizes an ultra-lightweight and highly compact, 100kg-class, satellite system with 1m-class spatial resolution SAR sensor. Considering future business prospects, the mass production cost around 2 billion yen is targeted in this program, which will be one-tenth of conventional systems. Our aimed system enables“ all-time and all-point observation” in whole world several ten minutes to several hours after launching under all condition, even at night and under rainy/cloudy/stormy weather.

Disruptive Innovation

Keys to the breakthrough


There are two points needed for major breakthroughs:
  • To realize achieve the compact SAR, selection of a third approach rather than the two major methods used worldwide (active phased array antenna system approach and parabola antenna system approach) to achieve the world’s most lightweight, most compact SAR system.
  • To realize achieve instant, on-demand observations, achievement of an fully automated operation process from separation, observation to downlink through photography, control through autonomous on-board decision-making that includes responding to abnormalities, and high-speed data communication system that completes the downlink of observation data in a single pass.

The Challenges for the PM and the Impact of Success

Overview and background

  • To provide emergency response in the event of a natural disaster or the like, the system must be able to respond instantaneously, as well as at night and under adverse weather conditions. It must also be able to respond to wide-area disasters and be able to simultaneously observe neighboring areas.
  • The achievement of a small SAR satellite system for on-demand observations will make it possible to build a system that can launch a satellite when needed to observe the necessary observation points, and that can make observations even at night or under adverse weather conditions.

What is the impact to industry and society if achieved?

  • The achievement of “a vital eye providing peace of mind” as a piece of social infrastructure needed for rapid response in the event of a natural disaster, man-made disaster and so on will minimize damage and enable a speedy response. This will contribute to safety and security for not only Japan but the rest of the world as well.
  • Creation of new businesses through the ability to observe areas with high rate of cloud coverage.
  • Use of real-time big data of observation data.
  • Enhancement of international competitiveness through the export of equipment sales and small SAR satellite systems.

Scenario for Success and Achievement Targets

Scenario for success

  • Achievement of a compact SAR system through selection of a third approach rather than the two major approach used worldwide (active phased array antenna system approach and parabola antenna system approach) to achieve the world’s most lightweight, most compact SAR system.
  • Development of the bus equipment (power source system and heat system) needed to achieve the compact SAR system in order to confirm validity as a satellite.
  • In terms of reliability, utilize the heritage of the Hodoyoshi satellite bus to create a compact, lightweight satellite not bound by the conventional approach to satellite development, in order to achieve a 100 kg class small satellite system.
  • Achievement of a high-speed data link capable of downlinking data in a single pass.
  • Achievement of advanced automation through the use of advanced onboard software and an operation model.
  • Continuous execution of benchmarks.

Achievement targets

  • SAR resolution: 1 m class
  • Weight: 100 kg class (1/10 that of a 1 ton class satellite)
  • Cost: 2 billion yen per satellite at the mass production stage (reducing the cost of several dozen billion yen to 1/10)
  • Immediate use capability: usable several dozen minutes to several hours after liftoff

Overall R&D Program Structure Created by the PM

  • In the satellite system project, research and development of on-demand functions (automation and autonomy) will be performed in order to achieve on-demand observations. These functions will be used to develop the new technologies needed to achieve the satellite bus that will accommodate the compact SAR system, and to perform ground verification.
  • In the SAR system project, research and development needed to achieve the compact, lightweight SAR system that is capable of high-density packaging will be performed, in order to achieve a flight-model level SAR system with the necessary functions and performance, and ground verification will be performed.
  • In the Integrated System Project, research and development of a small SAR satellite system, research and development of the ground system, the overall design that includes surveys to determine the needs of anticipated users, research and development of the platform, and research and development of the evaluation system, will be conducted, in order to create a system that achieves the objectives.

Implementation Structure as Assembled by the PM

  • The University of Tokyo was selected as the research and development institution for the Satellite System Project, as an institution capable of developing a satellite bus that would not involve high costs and would not be bound by conventional satellite development approaches with respect to reliability, and to serve as the contracted research organization that will lead research and development of on-demand functions (automation and autonomy) and satellite bus equipment.
  • JAXA and Tokyo Institute of Technology were selected as the contracted research institutions for the SAR System Project. These are the only institutions in the world that have presented approaches to resolving the issues of compactness of SAR system and weight reduction and miniaturization.
  • Keio University was established for the Integrated System Project as an institution with a thorough understanding of satellite systems and one that can coordinate with the diverse presumed users and organize these systems into a platform, and can also conduct research into evaluation systems.

Organization

The Cabinet Office
ImPACT: Small Synthetic Aperture Radar (SAR) Satellite System for On-Demand Observations
Seiko Shirasaka
Associate Program Manager
Shinobu Nakamura
Associate Program Manager
Takeshi Tohara