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公开(公告)号:JPH08105962A
公开(公告)日:1996-04-23
申请号:JP26090094
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: SAKURAI JOJI , YAJIMA MASANOBU , HISADA YASUMASA
Abstract: PURPOSE: To provide a radar device having the capability of giving a high resolution by using a relatively small antenna for reducing beam width substantially. CONSTITUTION: Regarding a radar device installed on the ground or mounted on a flight body such as a spaceship, an antenna system is formed out of the first and second transmission antennae 4 and 5, as well as the first and second receiving antennae 6 and 7. Also, the beam axes of the antennae 4 and 5 are inclined in directions opposite to each other, so as to form a transmission difference beam pattern 11 and the phase of a transmission beam from one of the antennae 4 and 5 is reversed. At the same time, beam axes of the antennae 6 and 7 are inclined in directions opposite to each other, so as to form a receiving difference beam pattern 14, and the phase of a receiving beam from one of the antennae 6 and 7 is reversed. Also, the directions of beam axes of the beam patterns 11 and 14 are made different from each other, and the antennae 4 and 5, and 6 and 7 are arranged, so that both difference beam patterns 11 and 14 are only partly superposed on an observation object zone, thereby forming equivalently small beam width.
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公开(公告)号:JPH11125673A
公开(公告)日:1999-05-11
申请号:JP28840797
申请日:1997-10-21
Applicant: MITSUBISHI ELECTRIC CORP , NAT SPACE DEV AGENCY
Inventor: TANAKA HIROKAZU , URASAKI SHUJI , FUJISAKA TAKAHIKO , IWAMOTO MASAFUMI , KONISHI YOSHIHIKO , HISADA YASUMASA , SAKURAI JOJI
Abstract: PROBLEM TO BE SOLVED: To realize high spacial resolution when loaded on a missile and observing planet surface, by utilizing collectively the observed data with chirp pulse from a plurality of orbits, and hypothetically forming a large array antenna. SOLUTION: A radar device observing a regolith layer of the moon, for example, is constituted of each device loaded on a moon satellite such as a chirp pulse 4 and antenna 7 and an image processor 10 placed on the ground. A specific chirp pulse from the antenna 7 is reflected by the regolith layer of the moon, received by the antenna 7 and transmitted to the ground. By the image processor 10, two dimensional synthetic open processing is done in horizontal direction for a plurality of adjacent orbit data, and pulse compression processing is done in the depth wise direction to obtain the thickness of the regolith layer. Thus, the chirp pulse with high frequency or double polarization or high frequency and double polarization is used, and pulse width control, data compression processing, elevation measurement, and switching to microwave measurement are also made possible.
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公开(公告)号:JPH08105955A
公开(公告)日:1996-04-23
申请号:JP26089794
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: SAKURAI JOJI , YAJIMA MASANOBU , HISADA YASUMASA
Abstract: PURPOSE: To provide a radar device having the capability of giving a high resolution by using a relatively small antenna for reducing beam width equivalently. CONSTITUTION: Regarding a radar to be installed on a moon-orbital observation satellite 1 or the like, a phased array antenna 4 is used as an antenna for transmission and receiving in common, and a feeding phase for each antenna element is adjusted for maintaining a difference in each beam axis between a transmission beam 6 at the time of transmission and a receiving beam 7 at the time of receiving, so as to superpose only a part of a transmission beam pattern and a receiving beam pattern on an observation object zone. Constitution is thereby made, so as to form a composite transmission and receiving beam 15 having equivalently narrow breadth.
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公开(公告)号:JPH08145648A
公开(公告)日:1996-06-07
申请号:JP30843994
申请日:1994-11-18
Applicant: NAT SPACE DEV AGENCY
Inventor: HISADA YASUMASA , SAKURAI JOJI , YAJIMA MASANOBU
Abstract: PURPOSE: To measure the depth of a surface structure highly accurately by detecting the resonance state of reflected wave in the surface structure from the voltage standing wave ratio, i.e., the ratio between a traveling wave based on the variation of frequency and each detection output of reflected wave. CONSTITUTION: A variable frequency oscillator 22 delivers a traveling wave and the intensity thereof is detected by means of a traveling wave detector 25 through a directional coupler 23 before being radiated tram an antenna 24 toward the surface of the moon 31. Waves reflected from the first and second surfaces 31-1, 31-2 of the moon 31 are received by the antenna 24 and separated from the traveling wave through the coupler 23 before the intensity thereof being detected through a reflected wave detector 26. The ratio of detection signal between the detectors 25, 26 is determined as a voltage standing wave ratio. The reflected wave from the surface 31-2 resonates when the wavelength thereof is in a predetermined relationship with the depth of a regolith 32 and does not return to the antenna 24. Consequently, the standing wave ratio is minimized. The depth of the regolith 32 can be determined based on the wavelength of traveling wave at that time and the known permittivity of the regolith.
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公开(公告)号:JPH08105967A
公开(公告)日:1996-04-23
申请号:JP26089894
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: HISADA YASUMASA , SAKURAI JOJI , YAJIMA MASANOBU
Abstract: PURPOSE: To provide a radar device capable of measuring an object for observation with a high resolution along a depthwise direction without using a large aperture antenna or narrow pulse width. CONSTITUTION: A radar device mounted on a moon-orbital observation satellite 1 or the like is provided with a transceiver section 2 for sending out the first transmission pulse f1 having a frequency reflected on the first moon surface 4-1 and not entering the moon soil, and the second transmission pulse f2 having a frequency entering the soil and reflected on the second moon surface 4-2, and then receiving the echo pulses thereof, as well as a signal processing circuit 11 for reversing the phase of the received echo pulse f1 ' of the first transmission pulse f1 and outputting the pulse f2 ' after the addition thereof to the second transmission echo pulse f2 '.
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公开(公告)号:JPH08105957A
公开(公告)日:1996-04-23
申请号:JP26089994
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: HISADA YASUMASA , SAKURAI JOJI , YAJIMA MASANOBU
Abstract: PURPOSE: To allow depthwise observation with a high resolution without using a large aperture antenna by observing an identical observation object from two directions at the time of passing up the north and passing down the south, with an antenna offset in an identical direction from a position directed immediately below, and applying mutual correlation treatment to two observation data. CONSTITUTION: A radar device 2 laid on a moon-orbital observation satellite 1 is formed out of a transmission and receiving section 3, an antenna 4 and a mutual correlation treatment section 5. The antenna 4 has a beam axis 11 offset by a certain angle γ from a position directed immediately below. An identical point on the moon surface 13 is observed twice from two different directions, for example, from a point PN for passing up the north and a point PS for passing down the south, both appearing due to the rotation of the moon along the orbit of the satellite 1. Furthermore, the section 5 subjects two echo signals received from the observation of the identical point on the moon surface along two directions. and extracts information on the thickness of the surface soil of the moon.
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公开(公告)号:JPH08105956A
公开(公告)日:1996-04-23
申请号:JP26090194
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: SAKURAI JOJI , YAJIMA MASANOBU , HISADA YASUMASA
Abstract: PURPOSE: To provide a radar device having the capability of giving a high resolution by using a relatively small antenna for reducing beam width substantially. CONSTITUTION: Regarding a radar device mounted on the ground, a spaceship or the like, a phased array antenna 4 is provided as an antenna for transmission and receiving in common. The beam axes of two transmission beams formed via the adjustment of a feeding phase for each antenna element are offset in opposite directions and the phase of one transmission beam is reversed to form a transmission differential beam pattern 6 as a transmission beam pattern. Also, two beam axes of two receiving beams formed via the adjustment of a feeding phase for each antenna element are offset in opposite directions, and the phase of one receiving beam is reversed to form a receiving differential beam pattern 7, as a receiving beam pattern. Furthermore, each of the beam axes of both beam patterns 6 and 7 are made different, and constitution is so made that both differential beam patterns 6 and 7 are only partly superposed on an observation object zone.
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公开(公告)号:JPH08105953A
公开(公告)日:1996-04-23
申请号:JP26089694
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: YAJIMA MASANOBU , SAKURAI JOJI , HISADA YASUMASA
Abstract: PURPOSE: To provide a radar device having the capability of giving a high resolution by using a relatively small antenna for reducing beam width substantially. CONSTITUTION: Regarding a radar to be installed on a moon-orbital observation satellite 1 or the like, a transmission antenna 4 and a receiving antenna 5 are separately provided, and arranged so as to have only a part of each antenna beam pattern superposed on an observation object zone, with beam axes kept different from each other. Also, the antenna 5 receives only the reflected beam of a transmission beam from the superposed section. According to this construction, a radar device with equivalently reduced beam width can be provided.
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公开(公告)号:JPH08102605A
公开(公告)日:1996-04-16
申请号:JP26090294
申请日:1994-10-03
Applicant: NAT SPACE DEV AGENCY
Inventor: SAKURAI JOJI
Abstract: PURPOSE: To obtain an antenna storing and expanding device capable of easily storing and expanding an antenna element. CONSTITUTION: The antenna element 1 is rotatably supported by an antenna element holder through a rotary shaft 11 and constituted so as to be rotationally exited to a laid storing position by a helical spring 13. A coil 16 consisting of shape memory alloy to be shortened at the time of heating is connected between a fixed hole formed on the base end of the element 1 and a fixed fitting 15 formed on the bottom part of the holder 12, a heater 17 for heating the coil 16 is heated to shorten the coil 16, the element 1 is rotationally excited to an erected expanded position, and a latch fitting 19 is engaged with the element 1 to hold the element 1 at the expanded position.
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公开(公告)号:JPH08189964A
公开(公告)日:1996-07-23
申请号:JP1558495
申请日:1995-01-06
Applicant: NAT SPACE DEV AGENCY
Inventor: SAKURAI JOJI , YAJIMA MASANOBU , HISADA YASUMASA
IPC: G01V3/17 , G01B15/02 , G01B17/02 , G01B21/08 , G01S7/03 , G01S13/08 , G01S13/50 , G01S13/88 , G01S15/89 , H01Q1/28
Abstract: PURPOSE: To provide a rotary radar apparatus which can obtain a high resolution irrespective of a beam width with the use of even a relatively small antenna. CONSTITUTION: A transmitting/receiving antenna 6 is mounted at the front end of a rotary arm 5 fixed to a rotary shaft 4 of a rotary device 3. The antenna 6 is rotated at a constant speed around the rotary shaft 4. A transmitter 9 is connected to the antenna 6 via a circulator 12, and a band pass filter 13 passing only receiving signals of the same frequency as a transmission frequency is arranged in a circuit to a receiver 10 branching from the circulator 12. The rotary radar apparatus is thus constituted.
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