JPH043511B2 - - Google Patents
Info
- Publication number
- JPH043511B2 JPH043511B2 JP16931282A JP16931282A JPH043511B2 JP H043511 B2 JPH043511 B2 JP H043511B2 JP 16931282 A JP16931282 A JP 16931282A JP 16931282 A JP16931282 A JP 16931282A JP H043511 B2 JPH043511 B2 JP H043511B2
- Authority
- JP
- Japan
- Prior art keywords
- doppler sensor
- electric field
- field strength
- vmax
- vmin
- 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.)
- Expired
Links
- 230000005684 electric field Effects 0.000 claims description 22
- 238000005259 measurement Methods 0.000 claims description 7
- 238000001514 detection method Methods 0.000 claims description 4
- 238000010586 diagram Methods 0.000 description 6
- 238000000034 method Methods 0.000 description 3
- 230000005855 radiation Effects 0.000 description 3
- 238000007796 conventional method Methods 0.000 description 1
- 238000006257 total synthesis reaction Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
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
- G01S7/00—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00
- G01S7/02—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00
- G01S7/41—Details of systems according to groups G01S13/00, G01S15/00, G01S17/00 of systems according to group G01S13/00 using analysis of echo signal for target characterisation; Target signature; Target cross-section
- G01S7/415—Identification of targets based on measurements of movement associated with the target
Description
【発明の詳細な説明】
本発明はマイクロ波ドツプラーセンサで検出し
た出力により反射物体の形状を知る方法に関す
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for determining the shape of a reflective object based on the output detected by a microwave Doppler sensor.
従来、目視不能状態での離隔位置からの物体有
無の検知はできても、物体の外形形状まで識別す
ることは実用的にできないこともあつて、検知物
体が目標とする物体であるかどうかを識別するた
めには、目標物体のみに生ずる特別の条件を見出
して検知するしかないという欠点があつた。 Conventionally, although it has been possible to detect the presence or absence of an object from a remote location when it is impossible to see it visually, it is not practical to identify the external shape of the object, so it has been difficult to determine whether the detected object is the target object or not. The disadvantage is that the only way to identify the target object is to find and detect special conditions that occur only with the target object.
本発明の目的は、静止した被測定物体に向けて
ドツプラセンサよりマイクロ波を放射し、その被
測定物体からの反射波の位相と大きさを求める操
作を、多数の測定点で行い、そこで得られた一連
のデータにフーリエ変換操作を行うことによつ
て、比較的簡単に物体の外形形状を離隔位置から
容易に識別することができる物体形状識別方法を
提供することによつて、前記従来の欠点を除去す
ることにある。 The purpose of the present invention is to emit microwaves from a Doppler sensor toward a stationary object to be measured, and to obtain the phase and magnitude of the reflected waves from the object at a large number of measurement points. By providing an object shape identification method that can relatively easily identify the external shape of an object from a remote position by performing a Fourier transform operation on a series of data, the above-mentioned drawbacks of the conventional method can be solved. The goal is to eliminate the
次に、本発明の一実施例の構成及び作用を原理
とともに図面によつて説明する。 Next, the structure and operation of an embodiment of the present invention will be explained with reference to the drawings together with the principle.
第１図において、形状識別用目標物体１の位置
する直線Ｌ１のマイクロ波反射特性をｇ（x1）と
したとき、直線Ｌ１と平行な直線Ｌ２に沿つて
cos2の指向特性をもつマイクロ波ドツプラーセン
サ２を移動する。 In Fig. 1, when the microwave reflection characteristic of the straight line L1 on which the shape identification target object 1 is located is g(x1), along the straight line L2 parallel to the straight line L1,
A microwave Doppler sensor 2 having a directional characteristic of cos 2 is moved.
このとき、
t1（x2）を直線Ｌ１上の一点（x1）位置に放射
されたマイクロ波の電界強度、
ｒ（x2）を直線Ｌ１より反射されてドツプラー
センサ２に入射するマイクロ波の全合成電界強度
とすると、ｒ（x2）は次のように表わされる。 At this time, t1(x2) is the electric field strength of the microwave radiated to a point (x1) on the straight line L1, and r(x2) is the total synthesis of the microwave reflected from the straight line L1 and incident on the Doppler sensor 2. In terms of electric field strength, r(x2) is expressed as follows.
ここで
−ｗ〜＋ｗを放射波の有効反射区間
αをドツプラーセンサ２に取付けられたホーン
アンテナ３のアンテナ定数
λをマイクロ波の波長
とする。 Here, −w to +w is the effective reflection interval of the radiated wave, α is the antenna constant of the horn antenna 3 attached to the Doppler sensor 2, and λ is the wavelength of the microwave.
次に、ここでｔ（x2）を、第１図の直線Ｌ２の
位置x2に置かれたドツプラセンサ２に組付けら
れたアンテナ３より放射される電界の中心軸上で
の強度、即ち、放射電界強度（x2に関係なく一
定）とすると、ｔ（x2）とt1（x2）との関係は
と表わされる。従つて(1)(2)より
ただしθ＝tan-1x2−x1／Ｄ
（参考文献、小沢 孝夫著「電気回路」P32〜
P34、昭晃堂、昭和55.5.30初版）
次に、ａ（x1）をホーンアンテナ３のアンテナ
特性（ホーンアンテナ３の放射角により決まる定
数）とし、
と定めると、
ｒ（x2）＝ｇ（x1）＊ａ（x1）
と表わされる。 Next, let t(x2) be the intensity on the central axis of the electric field radiated from the antenna 3 attached to the Doppler sensor 2 placed at the position x2 of the straight line L2 in FIG. Assuming the strength (constant regardless of x2), the relationship between t(x2) and t1(x2) is It is expressed as Therefore, from (1) and (2) However, θ=tan -1 x2−x1/D (References, “Electrical Circuits” by Takao Ozawa, P32~
P34, Shokodo, first edition on May 30, 1982) Next, let a(x1) be the antenna characteristic of the horn antenna 3 (a constant determined by the radiation angle of the horn antenna 3), Then, it is expressed as r(x2)=g(x1)*a(x1).
そこで、ｒ（x2）、ｇ（x1）、ａ（x1）のフーリエ
変換をＲ（ξ）、Ｇ（ξ）、Ａ（ξ）で表わせば、合
成定理より、
Ｒ（ξ）＝Ｆ〔ｇ（x1）＊ａ（x1）〕
＝Ｇ（ξ）・Ａ（ξ）
従つて、
ｇ（x1）＝F-1〔Ｇ（ξ）〕＝F-1〔Ｒ（ξ）
／Ａ（ξ）〕＝F-1〔Ｆ〔ｒ（x2）〕／Ｆ〔ａ（x1）〕
〕……(5)
ここで最右項は、反射波データｒ（x2）のフー
リエ変換Ｆ〔ｒ（x2）〕とアンテナ特性ａ（x1）の
フーリエ変換Ｆ〔ａ（x1）〕との比の逆フーリエ変
換が反射特性ｇ（x1）となることを示していま
す。 Therefore, if the Fourier transforms of r(x2), g(x1), and a(x1) are expressed as R(ξ), G(ξ), and A(ξ), then from the composition theorem, R(ξ)=F[g (x1) * a (x1)] = G (ξ)・A (ξ) Therefore, g (x1) = F -1 [G (ξ)] = F -1 [R (ξ)
/A(ξ)]=F -1 [F[r(x2)]/F[a(x1)]
]...(5) Here, the rightmost term is the ratio between the Fourier transform F[r(x2)] of the reflected wave data r(x2) and the Fourier transform F[a(x1)] of the antenna characteristic a(x1). It shows that the inverse Fourier transform of is the reflection characteristic g(x1).
このことは、第４図のＸ線上の０からX2にい
たるΔxづつ離れた多数の測定点x2において、そ
れぞれの反射波データｒ（x2）を求め、そのフー
リエ変換Ｆ〔ｒ（x2）〕を求めることが必要なこと
を示しております。また、求められる反射特性ｇ
（x1）はx1の関数となり、ある範囲のx1に対応す
る複数のデータが得られる。即ち、第６図に示す
ように、Ｚ軸上の測定値Ｖ（x2）の最大値Vmax
と最小値Vminから(6)式を用いてｒ（x2）を求め、
この操作により、第７図に示すように、Ｘ軸上０
からx2に至るΔx離れた点x20、x21、x22…につ
いてｒ（x20）、ｒ（x21）、ｒ（X22）…を求め、更
に、第８図に示すように、ｒ（x2）＝｛ｒ（x20）、
ｒ（x21）、ｒ（X22）…｝とアンテナ特性ａ（x1）
より(5)式を用いてｇ（x1）を求めることができ
る。 This means that each reflected wave data r(x2) is obtained at a large number of measurement points x2 separated by Δx from 0 to X2 on the X-ray in Figure 4, and its Fourier transform F[r(x2)] is calculated. It shows what you need to ask for. Also, the required reflection property g
(x1) is a function of x1, and multiple data corresponding to a certain range of x1 can be obtained. That is, as shown in FIG. 6, the maximum value Vmax of the measured value V(x2) on the Z axis
and the minimum value Vmin, use equation (6) to find r(x2),
By this operation, as shown in FIG.
Find r(x20), r(x21), r(X22)... for points x20, x21, x22... separated by Δx from (x20),
r(x21), r(X22)...} and antenna characteristics a(x1)
From this, g(x1) can be found using equation (5).
その結果、(5)式より、ドツプラセンサ２入射全
合成電界強度ｒ（x2）を測定することによりアン
テナ特性ａ（x1）を使つて（ｔ（x2）＝１として計
算可能）ｇ（x1）を求めることができる。 As a result, from equation (5), by measuring the total combined electric field strength r(x2) incident on the Doppler sensor 2, g(x1) can be calculated using the antenna characteristic a(x1) (can be calculated as t(x2) = 1). You can ask for it.
従つて、反射特性ｇ（x1）から目標物体１の形
状を知ることができる。 Therefore, the shape of the target object 1 can be known from the reflection characteristic g(x1).
そこで、ドツプラーセンサ２入射全合成電界強
度ｒ（x2）は次のようにして測定される（参考文
献、小沢 孝夫著「電気回路」P97、P108、昭
晃堂、昭和55.5.30初版）。 Therefore, the total combined electric field strength r(x2) incident on the Doppler sensor 2 is measured as follows (Reference, Takao Ozawa, "Electric Circuit", P97, P108, Shokodo, first edition on May 30, 1982).
ドツプラーセンサ２の検出信号Ｖ（x2）は入射
全合成電界ｒ（x2）と放射電界ｔ（x2）を用いて
次のように表わせる。 The detection signal V(x2) of the Doppler sensor 2 can be expressed as follows using the total incident electric field r(x2) and the radiated electric field t(x2).
Ｖ（x2）＝Ｋ｜ｔ（x2）＋ｒ（x2）｜2
（Ｋは定数）、このｔ（x2）とｒ（x2）の関係ベ
クトル図を第２図に示す。 V(x2)=K|t(x2)+r(x2)| 2 (K is a constant), and the relationship vector diagram between t(x2) and r(x2) is shown in FIG.
ここで、目標物体１と検出点との距離Ｄについ
てはＤ≫λ／４を満足するとき、Ｄが±λ／４の範囲で
変化しても、｜ｒ（x2）｜の変化は実験結果では数
％以下にとどまる。しかるにθはほぼ一π〜十π
の範囲で変化する。θ＝０のときＶ（x2）は極大
値Vmaxをとり、θ＝±πのとき、Ｖ（x2）は極
小値Vminをとる。 Here, when the distance D between the target object 1 and the detection point satisfies D≫λ/4, even if D changes within the range of ±λ/4, the change in |r(x2)| However, it remains below a few percent. However, θ is approximately 1π to 11π
Varies within the range of . When θ=0, V(x2) takes the maximum value Vmax, and when θ=±π, V(x2) takes the minimum value Vmin.
このとき
Vmax＝Ｋ｜ｔ（x2）＋ｒ（x2）｜2
＝Ｋ｛｜ｔ（x2）｜2＋２｜ｔ（x2）｜
・｜ｒ（x2）｜＋｜ｒ（x2）｜2｝
Vmim＝Ｋ｜ｔ（x2）−ｒ（x2）｜2
＝Ｋ｛｜ｔ（x2）｜2−２｜ｔ（x2）｜
・｜ｒ（x2）｜＋｜ｒ（x2）｜2｝
∴Vmax−Vmin＝4K｜ｔ（x2）｜・｜ｒ（x2）
｜
∴｜ｒ（x2）｜＝Vmax−Vmin／4K｜ｔ（x2）｜……(6
)
となり、ドツプラーセンサ２入射全合成電界強度
ｒ（x2）を求めることができる。 In this case, Vmax=K|t(x2)+r(x2)| 2 = K{|t(x2)| 2 +2|t(x2)| ・|r(x2)|+|r(x2)| 2 } Vmim = K | t (x2) - r ( x2 ) | 2 = K | −Vmin=4K｜t(x2)｜・｜r(x2)
｜ ∴｜r(x2)｜＝Vmax−Vmin／4K｜t(x2)｜……(6
), and the total combined electric field strength r(x2) incident on the Doppler sensor 2 can be obtained.
このことから、目標物体１の形状の識別は第３
図〜第５図のようにして行われる。 From this, the identification of the shape of the target object 1 is the third step.
This is carried out as shown in FIGS.
即ち、ドツプラーセンサ２から電磁波、例えば
マイクロ波を放射させることによる目標物体１か
らの反射波と前記放射波との合成電界強度に対応
したドツプラーセンサ２からの出力は第３図に示
すように、バツフアアンプ４とＡ／Ｄコンバータ
５を経てマイクロコンピユータ６に入力されると
ともに、このマイクロ波放射状態においてドツプ
ラーセンサ２を第４図Ｘ軸方向０〜X2上Δx×ｎ
の各位置（x2）に移動させ、この各位置（x2）
においてドツプラーセンサ２を目標物体１と対向
するＺ軸方向前後に変位させて前記各位置（x2）
における電界強度の最大値Vmaxと最小値Vmin
を測定し、この電界強度Vmax、Vminと放射電
界強度ｔ（x2）と定数Ｋとからドツプラーセンサ
２に入射される全合成電界強度｜ｒ（x2）｜＝
Vmax−Vmin／4K・｜ｔ（x2）｜を求め、更に、該全合成
電界強
度ｒ（x2）とドツプラーセンサ２のアンテナ特性
ａ（x1）とから目標物体１のマイクロ波反射特性
ｇ（x1）＝F-1〔Ｆ〔ｒ（x2）〕／Ｆ〔ａ（x1）〕〕を
求めるとともに、
このマイクロ波反射特性ｇ（x1）をドツプラーセ
ンサ２をＸ軸、Ｙ軸線上のΔx、Δy移動させた各
測定位置に従つてプロツトすることによつて目標
物体１の形状を求めることができる。 That is, the output from the Doppler sensor 2 corresponding to the combined electric field strength of the reflected wave from the target object 1 and the radiated wave caused by emitting electromagnetic waves, such as microwaves, from the Doppler sensor 2 is as shown in FIG. is inputted to the microcomputer 6 via the buffer amplifier 4 and the A/D converter 5, and in this microwave radiation state, the Doppler sensor 2 is input to the
to each position (x2), and this each position (x2)
, the Doppler sensor 2 is displaced back and forth in the Z-axis direction facing the target object 1 to obtain each of the above positions (x2).
Maximum value Vmax and minimum value Vmin of electric field strength at
The total combined electric field intensity |r(x2)|=
Vmax−Vmin/4K・|t(x2)| is determined, and further, the microwave reflection characteristic g( x1)=F -1 [F[r(x2)]/F[a(x1)]], and calculate this microwave reflection characteristic g(x1) by Δx on the X-axis and Y-axis of the Doppler sensor 2. , the shape of the target object 1 can be determined by plotting according to each measurement position moved by .DELTA.y.
なお、電磁波の周波数を任意に変化させること
によつて、夜間及び火中における物体の形状、ま
た、地下に埋設された物体の形状、例えばガス
管、水道管の太さ等を識別することができる。 By arbitrarily changing the frequency of electromagnetic waves, it is possible to identify the shape of objects at night or under fire, as well as the shape of objects buried underground, such as the thickness of gas pipes and water pipes. can.
次に、本発明の効果について説明する。 Next, the effects of the present invention will be explained.
本発明は形状検出用物体と任意距離隔てて対向
させたドツプラーセンサを、物体とドツプラーセ
ンサとを結ぶ直線とほぼ直交する面に沿つて移動
させるとともに、この移動途上の各位置（x2）
においてドツプラーセンサから電磁波を放射させ
ながらドツプラーセンサを物体と対向する方向に
前後に変位させて前記各位置における電界強度の
最大値Vmaxと最小値Vminを測定するとともに、
この電界強度Vmax、Vminと放射電界強度ｔ
（x2）と定数Ｋとからドツプラーセンサに入射さ
れる全合成電界強度｜ｒ（x2）｜＝
Vmax−Vmin／4K・｜ｔ（x2）｜を求め、更に、該全合成
電界強
度ｒ（x2）とドツプラーセンサのアンテナ特性ａ
（x1）とから物体の電磁波反射特性ｇ（x1）＝F-1
〔Ｆ〔ｒ（x2）〕／Ｆ〔ａ（x1）〕〕を求めるとともに
、この電磁波
反射特性ｇ（x1）をドツプラーセンサを移動させ
た各測定位置に従つてプロツトする物体形状識別
方法にある。 The present invention moves a Doppler sensor facing a shape detection object at an arbitrary distance along a plane substantially perpendicular to a straight line connecting the object and the Doppler sensor, and at each position (x2) along the way.
, while emitting electromagnetic waves from the Doppler sensor, displace the Doppler sensor back and forth in a direction facing the object and measure the maximum value Vmax and minimum value Vmin of the electric field strength at each position, and
This electric field strength Vmax, Vmin and radiation electric field strength t
Total combined electric field strength incident on the Doppler sensor from (x2) and constant K |r(x2)|=
Vmax−Vmin/4K・|t(x2)| is determined, and further, the total combined electric field strength r(x2) and the antenna characteristic a of the Doppler sensor
(x1) and the electromagnetic wave reflection property of the object g(x1) = F -1
An object shape identification method that calculates [F[r(x2)]/F[a(x1)]] and plots this electromagnetic wave reflection characteristic g(x1) according to each measurement position where the Doppler sensor is moved. be.
これによつて、本発明は目視不能状態での離隔
位置から物体の外形形状を容易に識別することが
できる効果がある。 As a result, the present invention has the effect that the external shape of an object can be easily identified from a remote position in a state where it is not visible to the naked eye.
第１図は本発明の一実施例の原理説明図、第２
図はその原理説明のための電界強度のベクトル
図、第３図はその電気系統図、第４図と第６図〜
第８図はその測定状況を示す説明図、第５図はそ
の測定のマイクロ制御用フローチヤート図であ
る。
１……目標物体、２……ドツプラーセンサ、３
……ホーンアンテナ、４……バツフアアンプ、５
……Ａ／Ｄコンバータ、６……マイクロコンピユ
ータ。
Figure 1 is a diagram explaining the principle of one embodiment of the present invention, Figure 2 is a diagram explaining the principle of an embodiment of the present invention.
The figure is a vector diagram of electric field strength to explain the principle, Figure 3 is the electrical system diagram, Figures 4 and 6~
FIG. 8 is an explanatory diagram showing the measurement situation, and FIG. 5 is a flow chart for microcontrol of the measurement. 1...Target object, 2...Doppler sensor, 3
……Horn antenna, 4……Battery amplifier, 5
...A/D converter, 6...Microcomputer.
Claims (1)
ドツプラーセンサを、物体とドツプラーセンサと
を結ぶ直線とほぼ直交する面に沿つて移動させる
とともに、この移動途上の各位置（x2）におい
てドツプラーセンサから電磁波を放射させながら
ドツプラーセンサを物体と対向する方向に前後に
変位させて前記各位置における電界強度の最大値
Vmaxと最小値Vminを測定するとともに、この
電界強度Vmax、Vminと放射電界強度ｔ（x2）
と定数Ｋとからドツプラーセンサに入射される全
合成電界強度｜ｒ（x2）｜＝Vmax−Vmin／4K・｜ｔ（x2
）｜を 求め、更に、該全合成電界強度ｒ（x2）とドツプ
ラーセンサのアンテナ特性ａ（x1）とから物体の
電磁波反射特性ｇ（x1）＝F-1〔Ｆ〔ｒ（x2）〕／Ｆ〔
ａ（x1）〕〕を求 めるとともに、この電磁波反射特性ｇ（x1）をド
ツプラーセンサを移動させた各測定位置に従つて
プロツトすることを特徴とする物体形状識別方
法。[Scope of Claims] 1. A Doppler sensor facing a shape detection object at an arbitrary distance is moved along a plane substantially perpendicular to a straight line connecting the object and the Doppler sensor, and each point along the way is moved. While emitting electromagnetic waves from the Doppler sensor at position (x2), the Doppler sensor is displaced back and forth in the direction facing the object, and the maximum value of the electric field strength at each of the above positions is determined.
Measure Vmax and minimum value Vmin, and calculate the electric field strength Vmax, Vmin and the radiated electric field strength t(x2)
The total combined electric field strength incident on the Doppler sensor from
)|, and further, from the total combined electric field strength r(x2) and the antenna characteristic a(x1) of the Doppler sensor, the electromagnetic wave reflection characteristic of the object g(x1)=F -1 [F[r(x2)] /F [
a(x1)] and plotting this electromagnetic wave reflection characteristic g(x1) according to each measurement position to which a Doppler sensor is moved.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16931282A JPS5957182A (en) | 1982-09-27 | 1982-09-27 | Identification of shape of object |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP16931282A JPS5957182A (en) | 1982-09-27 | 1982-09-27 | Identification of shape of object |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS5957182A JPS5957182A (en) | 1984-04-02 |
| JPH043511B2 true JPH043511B2 (en) | 1992-01-23 |
Family
ID=15884196
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP16931282A Granted JPS5957182A (en) | 1982-09-27 | 1982-09-27 | Identification of shape of object |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS5957182A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2720355C1 (en) * | 2019-08-09 | 2020-04-29 | Михаил Васильевич Захаров | Target recognition radiolocation station |
| WO2023021763A1 (en) * | 2021-08-20 | 2023-02-23 | コニカミノルタ株式会社 | State detection system and state detection method |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103513246B (en) * | 2013-10-09 | 2015-11-04 | 中国科学院空间科学与应用研究中心 | A kind of system and method for sub-wavelength imaging |
-
1982
- 1982-09-27 JP JP16931282A patent/JPS5957182A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2720355C1 (en) * | 2019-08-09 | 2020-04-29 | Михаил Васильевич Захаров | Target recognition radiolocation station |
| WO2023021763A1 (en) * | 2021-08-20 | 2023-02-23 | コニカミノルタ株式会社 | State detection system and state detection method |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS5957182A (en) | 1984-04-02 |
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