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ABSTRACT: Huge antennas has many useful applications in space as well as on the ground, for example, Solar Power Satellite to provide electricity to the ground, telecommunication for cellular phones, radars for remote sensing, navigation and observation, and so on. The S-310-36 sounding rocket was successfully launched on 22 January 2006 to verify our newly proposed scheme to construct huge antennas under microgravity condition in space. The rocket experiment has three main objectives, the first objective of which is to verify the Furoshiki deployment system [S. Nakasuka, R. Funase, K. Nakada, N. Kaya, J. Mankins, Large membrane "FUROSHIKI Satellite" applied to phased array antenna and its sounding rocket experiment, in: Proceedings of the 54th International Astronautical Congress, 2003. [1]], the second is to test the retrodirective antenna system to correct the distortion of the structures in a long range from space to the ground as mentioned above and the last is a microgravity test of the crawling robots on the deployed mesh. The payload section is composed of four sections. The mesh is installed at the top section and the two robots are in the box at the second section under the mesh. The daughter sections at the third section are attached to the mother section, while the momentum wheel is stored in the bottom section. The telemeters and the timer are in the CI section under the payload one. The three sections above the daughter ones are covered by a nose cone. The rocket motor was separated from the payload section to reduce the momentum of the payload, while the nose cone was released after the launch. The payload section was precisely stopped to spin by the momentum wheel for the deployment of the mesh. The mesh would be tangled in case the spinning of the payload section could not perfectly be stopped. The three daughter sections were separated by springs to deploy the mesh installed on the top of the mother section. The daughter sections might be bounced toward the mother section without a position control. Therefore the daughter section had a gas jet to stop the rebound and keep the strength of the mesh. The microwave transmitters were turned on to radiate the microwave toward the ground according to the pilot signal transmitted from the ground station. These transmitters had a retrodirective antenna system to control precisely the direction of the microwave toward the transmitting antenna of the pilot signal. The retrodirective antenna system can decide the output phases of the microwave by conjugating the received phases of the pilot signal. The two robots started to crawl toward the separated daughter sections on the mesh after the deployment.
Acta Astronautica. 01/2009; 65(1-2):202-205.
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ABSTRACT: A new concept for a retrodirective tracking system applicable for communication and power transmission is proposed. In the proposed concept, the power transmitter utilizes a receiver's pilot signal to obtain information about its direction by conjugating the signal's phase inside a nonlinear medium. Power is therefore transmitted back to the receiver by the phase-conjugated signal beam. The power can be concentrated by an array of phase conjugators, which provides a large aperture so that the intensity can be increased on the receiver's photovoltaic panels compared to a single element. Controlling the phase and the direction of the readout beams in the four-wave-mixing process provides control over the interference pattern, its position, and its size. A numerical analysis is given for the phase and spot size control, and measurements with two Co-doped Sr(x)Ba(1-x)Nb(2)O(6) (Co:SBN) crystals confirm the occurrence of interference that is achieved for the case of two beams.
Applied Optics 08/2007; 46(21):4633-41. · 1.41 Impact Factor
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IAC 2006, Valencia, Spain; 01/2006
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IAC 2006, Valencia, Spain; 01/2006
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IAC 2005, Fukuoka, Japan; 01/2005
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Journal of the British Interplanetary Society. 01/2005; 58(11/12):402-406.
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IAC 2005, Fukuoka, Japan; 01/2005
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ISTS'04, Miyazaki, Japan; 01/2004
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ABSTRACT: University of Tokyo and Kobe University are planning a sounding rocket experiment of large membrane “Furoshiki Satellite” extension and large phased array RF transmission. The paper will describe the concept of “Furoshiki Satellite,” its application to phased array antenna, and the scenario of micro gravity experiment using a small sounding rocket.University of Tokyo has been proposing the idea of “Furoshiki Satellite,” a large membrane or a net structure, say in size, extended by satellites which hold its corners. The attitude and the shape of the membrane or net structure is controlled by these corner satellites. As one application of Furoshiki Satellite, a large phased array antenna can be configured by several RF transmitters placed on several parts of the large net structure. It is difficult to control the position and attitude of the RF transmitters precisely, but using the “retro-directive” method, the tolerance of such position and attitude disturbance will be relaxed by large. This is one of promising systems’ concept of the future large solar power satellite or large antenna, because quite a large area can be obtained without any hard structure, and the weight will not depend very much on the size [S. Motohashi, T. Nagamura, Large scaled membrane structure Furoshiki Satellite—its concept and orbital/attitude dynamics, in: Proceedings of 20th International Symposium on Space Technology and Science (ISTS), 1996, p. 96-n-14].To demonstrate the feasibility of the extension of large net structure and phased array performance, micro-gravity experiment is planned using a sounding rocket of ISAS/JAXA, Japan.
Acta Astronautica.
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ABSTRACT: We succeeded in the JAXA/ISAS sounding rocket experiment on the "Furoshiki" deployment (1), the retrodirective antenna and the crawling robots on the deployed mesh in January, 2006, as we presented the result at the last IAC in Valencia. The S-310-36 sounding rocket was launched to verify our newly proposed scheme to construct huge structures under microgravity condition in space. The rocket experiment had three main objectives, the first objective of which was to verify the Furoshiki deployment system, the second was to test the retrodirective antenna system to correct the distortion of the structures in a long range from space to the ground as mentioned above and the last is a microgravity test of the crawling robots on the deployed mesh. The payload section was composed of four sections. The mesh was installed at the top section and the two robots were in the box at the second section under the mesh. The daughter sections at the third section were attached to the mother section, while the momentum wheel was stored in the bottom section. The telemeters and the timer were in the CI section under the payload one. The three sections above the daughter ones were covered by a nose cone. We are planning the next demonstration for the Solar Power Satellite after the sounding rocket experiment. We believe the fundamental beam control system of the microwave has been established by the sounding rocket experiment, which is one of the most important and critical issues to realize the SPS. Our next plan is an orbiter experiment to carry out the beam control test with a pilot signal from the ground. We are launching small several satellites to extend the Furoshiki deployment, which can work a test bed to investigate the functions of the Sandwich panels and robotic technologies related to the SPS. We launch many Sandwich panels with the antenna element to work as an active phased array antenna after the construction of the large mesh. Each antenna element, which receives the pilot signal transmitted from the large parabola antenna on the ground, transmits a radio wave of the different frequency from the pilot signal by controlling the output phase to the ground. This space experiment is the first trial in the world to construct the real small Solar Power Satellite.
