JPS60257380A - Image processing method of synthetic aperture radar - Google Patents

Image processing method of synthetic aperture radar

Info

Publication number
JPS60257380A
JPS60257380A JP59112209A JP11220984A JPS60257380A JP S60257380 A JPS60257380 A JP S60257380A JP 59112209 A JP59112209 A JP 59112209A JP 11220984 A JP11220984 A JP 11220984A JP S60257380 A JPS60257380 A JP S60257380A
Authority
JP
Japan
Prior art keywords
frequency
image
synthetic aperture
aperture radar
received
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP59112209A
Other languages
Japanese (ja)
Other versions
JPH0224478B2 (en
Inventor
Shigeru Morimoto
森本　盛
Yasumasa Hisada
安正 久田
Yasuyuki Ito
康之 伊東
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
National Space Development Agency of Japan
Original Assignee
National Space Development Agency of Japan
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by National Space Development Agency of Japan filed Critical National Space Development Agency of Japan
Priority to JP59112209A priority Critical patent/JPS60257380A/en
Publication of JPS60257380A publication Critical patent/JPS60257380A/en
Publication of JPH0224478B2 publication Critical patent/JPH0224478B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/02—Systems using reflection of radio waves, e.g. primary radar systems; Analogous systems
    • G01S13/06—Systems determining position data of a target
    • G01S13/08—Systems for measuring distance only
    • G01S13/10—Systems for measuring distance only using transmission of interrupted, pulse modulated waves
    • G01S13/24—Systems for measuring distance only using transmission of interrupted, pulse modulated waves using frequency agility of carrier wave
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S13/00—Systems using the reflection or reradiation of radio waves, e.g. radar systems; Analogous systems using reflection or reradiation of waves whose nature or wavelength is irrelevant or unspecified
    • G01S13/88—Radar or analogous systems specially adapted for specific applications
    • G01S13/89—Radar or analogous systems specially adapted for specific applications for mapping or imaging
    • G01S13/90—Radar or analogous systems specially adapted for specific applications for mapping or imaging using synthetic aperture techniques, e.g. synthetic aperture radar [SAR] techniques
    • G01S13/904—SAR modes

Landscapes

  • Engineering & Computer Science (AREA)
  • Remote Sensing (AREA)
  • Radar, Positioning & Navigation (AREA)
  • Physics & Mathematics (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • General Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Image Processing (AREA)
  • Radar Systems Or Details Thereof (AREA)
  • Image Analysis (AREA)

Abstract

PURPOSE:To identify easily an object by assigning each color of three primary colors to three image outputs obtained by three frequencies, and forming an artificial color synthetic picture by superposing them. CONSTITUTION:In a three frequency synthetic aperture radar 11, pulse signals of three different frequencies F1, F2 and F3 are sent out simultaneously from each transmitter, pulse waves are radiated toward the same object to be observed G from each antenna 12-1, 12-2 and 12-3 connected to each transmitter, each reflected wave is received by each antenna 12-1, 12-2 and 12-3 and received by a receiver, and each received signal is recorded. By bringing these recorded data to a batch operation processing, they are imaged at every frequency, respectively. With respect to each image output of three pieces obtained at every frequency by this imaging processing, for instance, red, green and blue and assigned to the frequencies F1, F2 and F3, respectively, and monocolor images 13-1, 13-2 and 13-3 are superposed, by which an artificial color synthetic image 14 is obtained. In such a way, a floating phenomenon of an object being a purpose is generated, and it can be identified easily.

Description

【発明の詳細な説明】 〔発明の技術分野〕 、二の発明は、人工衛星等の飛翔体に搭載される合成開
口レーダの画像処理方法に関する。Detailed Description of the Invention [Technical Field of the Invention] The second invention relates to an image processing method for a synthetic aperture radar mounted on a flying object such as an artificial satellite.

〔発明の技術的背景と問題点〕[Technical background and problems of the invention]

一般に、人工衛星や航空機等の飛翔体（プラントフオー
ム）に搭載した映像レーダから、移動飛翔体の側方の地
上に電波を発射し、移動しながらこの反射波を受信して
、その受信信号を記録しておいて、一括演算処Ｉｇ！（
ホログラフインク処理）することにより、比較的小さい
［１旧］のアンテナで、実効的に大開口のアンテナを合
成することができるようにした合成開口レーダはよく知
られている。In general, a video radar mounted on a flying object (plant form) such as an artificial satellite or an aircraft emits radio waves to the ground on the side of the moving object, receives the reflected waves while moving, and receives the received signal. Record it and perform batch calculation Ig! (
Synthetic aperture radar is well known in which a relatively small [1st] antenna can be effectively synthesized into a large aperture antenna by using holographic ink processing).

そして、かかる合成開口レーダは、映像センサとして用
いられ、全天候型で昼夜の区別なく高分解能の画像を得
ることができるものである。Such a synthetic aperture radar is used as a video sensor, and is all-weather and can obtain high-resolution images regardless of day or night.

第１図は、かかる合成開口レーダの概略構成を示す図で
ある。図において、１は人工衛星や航空機等の飛翔体（
プラントフオーム）、２は送信機、３は受信機、４は送
受分波器、５は受信機３で受信した受信電波を記録する
受信電波記録装置、６はアンテナである。FIG. 1 is a diagram showing a schematic configuration of such a synthetic aperture radar. In the figure, 1 is a flying object such as an artificial satellite or an aircraft (
2 is a transmitter, 3 is a receiver, 4 is a transmitter/receiver branching filter, 5 is a received radio wave recording device for recording the received radio waves received by the receiver 3, and 6 is an antenna.

このように構成されている合成開口レーダにおいて、合
成開口レーダアンテナ６は飛翔体１に固定されており、
第２図に示すように、飛翔体１の移動に伴ってアンテナ
６から、時々刻々ある特定の間隔（パルス繰り返し周期
）で、間欠的に一定の周波数Ｆｏのパルス状の電波を地
、ト対象物Ｇに輻射し、その地上対象物Ｇからの反射電
波を、同じアンテナ６で受けて、受信機３で受信し、記
録装置ｆｔ５に記？、ＡするようになゲＣいる。そして
、前述の如く、この記録受信信号を一括演算処理して、
画像を再生するものである。In the synthetic aperture radar configured in this way, the synthetic aperture radar antenna 6 is fixed to the flying object 1,
As shown in Figure 2, as the flying object 1 moves, the antenna 6 intermittently sends pulsed radio waves of a constant frequency Fo to the ground and target at specific intervals (pulse repetition period). The radio waves radiated to the object G and reflected from the ground object G are received by the same antenna 6, received by the receiver 3, and recorded in the recording device ft5. , there is a game C like A. Then, as mentioned above, this recorded reception signal is subjected to batch calculation processing,
It plays back images.

ところで、この際、輻射されるパルス電波の周波数Ｆｏ
は、所望の観測すべき対象物によって適当に選定され、
〜周波に固定されているのが従来の方式である。したが
って、処理画像も白黒が、モノカラーのものしか得られ
ず、観測された対象物と使用したパルス電波の周波数帯
及び得られた画像との間の対応関係は不明な点が多く、
光領域で観察される対象物が合成開口レーダでは実際に
どのように見えるかが未だ解明されておらず、合成開口
レーダで得られる画像のメリットが不明であり、利用面
での研究が進展していないのが現状である。By the way, at this time, the frequency Fo of the radiated pulse radio waves is
is appropriately selected depending on the desired object to be observed,
The conventional method is to fix the frequency to ~. Therefore, processed images can only be obtained in black and white or monochrome, and there are many points that are unclear about the correspondence between the observed object, the frequency band of the pulsed radio waves used, and the obtained image.
It is still not clear how objects observed in the optical domain actually appear with synthetic aperture radar, and the merits of images obtained with synthetic aperture radar are unclear, and research on its use is progressing. The current situation is that this is not the case.

〔発明の目的〕[Purpose of the invention]

本発明は、従来の合成開口ルーダにおけるががる問題点
を解消すべくなされたもので、疑似カラー合成画像を形
成して観測対象物との対応関係を明確にし、観測対象物
の識別が容易に得られるようにした合成開口レーダの画
像処理方法を提供することを目的とするものである。The present invention was made in order to solve the problem of looseness in conventional synthetic aperture routers, and it forms a pseudo-color composite image to clarify the correspondence with the observed object, making it easy to identify the observed object. It is an object of the present invention to provide an image processing method for synthetic aperture radar that can be obtained.

〔発明の概要〕[Summary of the invention]

それぞれ異なる周波数を用いた３周波合成開ロレーダで
同一対象物を観測し、各周波数毎に得られた各画像出力
に、３原色の各色をそれぞれ割り当ててモノカラー画像
を形成し、これらのモノカラー画像を重ね合わせて疑似
カラー合成画像を得て、観測対象物と該カラー合成画像
との対応関係を明確にし、観測対象物の識別を容易に行
なえるようにするものである。The same object is observed with a three-frequency synthetic open radar using different frequencies, and each of the three primary colors is assigned to each image output obtained for each frequency to form a monocolor image. The images are superimposed to obtain a pseudo-color composite image, and the correspondence between the observed object and the color composite image is clarified, so that the observed object can be easily identified.

〔発明の実施例〕[Embodiments of the invention]

以下本発明の実施例について説明する。 Examples of the present invention will be described below.

第２図は、本発明の一実施例を示す説明図である。図に
おいて、１１は人工衛星等の飛翔体で、該飛翔体１１に
は３周波合成開ロレーダが搭載されている。この実施例
における３周波合成開ロレーダは、３つの異なる周波数
の送・受信機及び異なる周波数のパルス電波を放射する
アンテナ１ｚ−＋、　１２−２．１２−３を備えている
。FIG. 2 is an explanatory diagram showing one embodiment of the present invention. In the figure, reference numeral 11 denotes a flying object such as an artificial satellite, and the flying object 11 is equipped with a three-frequency synthetic radar. The three-frequency synthetic open radar in this embodiment includes transmitters/receivers of three different frequencies and antennas 1z-+, 12-2, and 12-3 that radiate pulse radio waves of different frequencies.

このように構成されている３周波合成開ロレーダにおい
て、各送信機から３つの異なる周波数ＦいＦ２．　Ｆ、
ｌのパルス信号を同時に送出し、それぞれに接続された
各アンテナ＋２−＋、　１２−２．１２−３からパルス
電波を、同一観測対象物Ｇに向けて放射し、その各反射
波を各アンテナ１２−１．１２−２．１２−ｚで受けて
受信機で受信し、各受信信号を記録しておいて、該記録
データを一括演算処理することにより、周波数毎にそれ
ぞれ画像化される。この画像化処理により各周波数毎に
得られる３個の各画像出力に、３原色の各色を適当に、
例えば、第１周波数Ｆ、、第２周波数Ｆ２　第２周波数
Ｆ２により得られる各画像出力に、それぞれ赤色、緑色
、青色を割り当てて、第４図に示すように、モノカラー
画像１３−、．１３−２、】３−３を形成し、次いで、
この処理によって得られた３原色の各色のモノカラー画
像＋３−、、１３−２．１３−３を重ね合わせることに
よって、疑似カラー合成画像１４を得るものである。In the three-frequency synthetic open radar configured in this manner, three different frequencies F, F2, and F2 are transmitted from each transmitter. F,
1 pulse signals are simultaneously sent out, and pulse radio waves are emitted from each of the antennas +2-+ and 12-2. 12-1.12-2.12-z and is received by a receiver, each received signal is recorded, and the recorded data is collectively processed to form an image for each frequency. Appropriately apply each of the three primary colors to each of the three image outputs obtained for each frequency through this imaging process.
For example, by assigning red, green, and blue to each image output obtained by the first frequency F, second frequency F2, and second frequency F2, monocolor images 13-, . 13-2, ]3-3, and then
A pseudo-color composite image 14 is obtained by superposing the monochrome images of the three primary colors obtained through this process, +3-, , 13-2, and 13-3.

このようにして得られた観測対象物の疑似カラー合成画
像によれば、白黒テレビをカラー化した場合と同様な効
果、すなわち、目的とする対象物の浮上化などの現象が
生じ、識別が容易になる等の効果を得ることが可能とな
る。According to the pseudo-color composite image of the observation target obtained in this way, the same effect as when colorizing a black-and-white television, that is, phenomena such as the levitation of the target object, occurs, making it easy to identify. It is possible to obtain effects such as

また、異なる３周波で得られたそれぞれの画像出力と、
それらに対する３原色の各色の組合わせを適宜選定する
ことにより、より自然色に近い画像を得たり、あるいは
、観測域内のあべ１特定な対象物、例えば、農業関係で
は作物、土壌自体、土地の含水分布等、鉱工業関係では
資源の倚無に関係する土地の摺曲構造等、海洋関係では
海水温度分布、波浪等、を強調したりすることが可能に
なる。In addition, each image output obtained at three different frequencies,
By appropriately selecting the combination of the three primary colors, it is possible to obtain images that are closer to natural colors, or to capture images of specific objects within the observation area, such as crops, the soil itself, or the land itself. It becomes possible to emphasize water content distribution, etc. in the mining industry, such as the curving structure of land that is related to the availability of resources, and in the ocean, seawater temperature distribution, waves, etc.

なお、上記実施例では、ｊｌ’）　ｙＪ＋体に搭載する
３周波合成開ロレーダは、送・受信機及びアンテナ等を
別個に３個ずつ備えて構成したものを示したが、３周波
合成開ロレーダは１本発明者らが先Ｇこ（π案した華−
の装置で異なる３′つの周波数のパルス電波を、１パル
スずつ順次繰り返して送出するように構成したもの（特
願昭５９−２５１７３号）も使用することができる。In the above embodiment, the 3-frequency synthetic open radar mounted on the jl') yJ+ body was constructed with three separate transmitters, receivers, antennas, etc.; The present inventors first proposed G(π).
It is also possible to use a device (Japanese Patent Application No. 59-25173) configured to sequentially and repeatedly transmit pulsed radio waves of 3' different frequencies one pulse at a time.

〔発明の効果〕〔Effect of the invention〕

以上実施例について説明したように、本発明によれば、
３周波によって得られる３つの画像出力に３原色の各色
をそれぞれ割り当てて、それらを重ね合わせて疑イ以カ
ラー合成画像を形成することによって、合成開口レーダ
において、観測対象物と画像の対応関係が明確になり、
対象物の識別が容易にできる等の効果が得られる。As described above with respect to the embodiments, according to the present invention,
By assigning each of the three primary colors to the three image outputs obtained by the three frequencies and superimposing them to form a composite color image, synthetic aperture radar can establish the correspondence between the observed object and the image. become clear,
Effects such as easy identification of objects can be obtained.

【図面の簡単な説明】[Brief explanation of the drawing]

第１図は、従来の合成開口レーダの一例の概略構成図〜
第２図は、その動作態様を示す説明図、第３図は、本発
明に係る合成量１］レーダの画像処理方法の一実施例の
説明図、第４図は、第３図に示した実施例の画像処理態
様を示す説明図である。 図において、１１は飛翔体、Ｊ２−１．１２−２．１２
−３はアンテナ、１３−１、】３−ｚ、　＋１はモノカ
ラー画像、１４はカラー合成画像を示す。 特許出願人宇宙開発事業団 代理人弁理士　最　上　健　治 第１区 第２図 第３図 第４図Figure 1 is a schematic configuration diagram of an example of a conventional synthetic aperture radar.
FIG. 2 is an explanatory diagram showing its operation mode, FIG. 3 is an explanatory diagram of an embodiment of the composite amount 1] radar image processing method according to the present invention, and FIG. It is an explanatory diagram showing an image processing mode of an example. In the figure, 11 is a flying object, J2-1.12-2.12
-3 is an antenna, 13-1, ]3-z, +1 is a monochrome image, and 14 is a color composite image. Patent applicant Kenji Mogami Patent attorney representing the Japan Space Development Agency District 1 Figure 2 Figure 3 Figure 4

Claims (1)

【特許請求の範囲】[Claims] ３つの異なる周波数を用いた３周波合成開ロレーダで同
一対象物を観測し、各周波数毎に得られた各画像出力に
、３原色の各色をそれぞれ割り当ててモノカラー画像を
形成し、次いで各モノカラー画像を重ね合ねゼでカラー
合成画像を得るようにしたごとを特徴とする合成開口レ
ーダの画像処理力ｌｊマ。The same object is observed with a three-frequency synthetic open radar using three different frequencies, and each image output obtained for each frequency is assigned each of the three primary colors to form a monochrome image. The image processing power of a synthetic aperture radar is characterized in that a color composite image is obtained by overlapping color images.
JP59112209A 1984-06-02 1984-06-02 Image processing method of synthetic aperture radar Granted JPS60257380A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP59112209A JPS60257380A (en) 1984-06-02 1984-06-02 Image processing method of synthetic aperture radar

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP59112209A JPS60257380A (en) 1984-06-02 1984-06-02 Image processing method of synthetic aperture radar

Publications (2)

Publication Number Publication Date
JPS60257380A true JPS60257380A (en) 1985-12-19
JPH0224478B2 JPH0224478B2 (en) 1990-05-29

Family

ID=14580980

Family Applications (1)

Application Number Title Priority Date Filing Date
JP59112209A Granted JPS60257380A (en) 1984-06-02 1984-06-02 Image processing method of synthetic aperture radar

Country Status (1)

Country Link
JP (1) JPS60257380A (en)

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US10230925B2 (en) 2014-06-13 2019-03-12 Urthecast Corp. Systems and methods for processing and providing terrestrial and/or space-based earth observation video
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US10871561B2 (en) 2015-03-25 2020-12-22 Urthecast Corp. Apparatus and methods for synthetic aperture radar with digital beamforming
US10955546B2 (en) 2015-11-25 2021-03-23 Urthecast Corp. Synthetic aperture radar imaging apparatus and methods
US11378682B2 (en) 2017-05-23 2022-07-05 Spacealpha Insights Corp. Synthetic aperture radar imaging apparatus and methods for moving targets
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Publication number Priority date Publication date Assignee Title
JP2003085532A (en) * 2001-09-07 2003-03-20 Communication Research Laboratory Land use classification processing method using sar image
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US9529081B2 (en) 2013-04-03 2016-12-27 The Boeing Company Using frequency diversity to detect objects
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GB2512739B (en) * 2013-04-03 2015-08-12 Boeing Co Using frequency diversity to detect objects
US20160103216A1 (en) * 2013-04-03 2016-04-14 The Boeing Company Using frequency diversity to detect objects
JP5636085B1 (en) * 2013-12-27 2014-12-03 アジア航測株式会社 Single-polarization SAR color image creation device
US10230925B2 (en) 2014-06-13 2019-03-12 Urthecast Corp. Systems and methods for processing and providing terrestrial and/or space-based earth observation video
US10871561B2 (en) 2015-03-25 2020-12-22 Urthecast Corp. Apparatus and methods for synthetic aperture radar with digital beamforming
US10615513B2 (en) 2015-06-16 2020-04-07 Urthecast Corp Efficient planar phased array antenna assembly
US10955546B2 (en) 2015-11-25 2021-03-23 Urthecast Corp. Synthetic aperture radar imaging apparatus and methods
US11754703B2 (en) 2015-11-25 2023-09-12 Spacealpha Insights Corp. Synthetic aperture radar imaging apparatus and methods
US11378682B2 (en) 2017-05-23 2022-07-05 Spacealpha Insights Corp. Synthetic aperture radar imaging apparatus and methods for moving targets
US11506778B2 (en) 2017-05-23 2022-11-22 Spacealpha Insights Corp. Synthetic aperture radar imaging apparatus and methods
US11525910B2 (en) 2017-11-22 2022-12-13 Spacealpha Insights Corp. Synthetic aperture radar apparatus and methods

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Publication number Publication date
JPH0224478B2 (en) 1990-05-29

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