JPH0225786A - Speed detecting device - Google Patents
Speed detecting deviceInfo
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- JPH0225786A JPH0225786A JP17664288A JP17664288A JPH0225786A JP H0225786 A JPH0225786 A JP H0225786A JP 17664288 A JP17664288 A JP 17664288A JP 17664288 A JP17664288 A JP 17664288A JP H0225786 A JPH0225786 A JP H0225786A
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- 238000010586 diagram Methods 0.000 description 12
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Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は速度検出装置に関し、特に速度が早くかつ速度
変化の大きい移動物体を対象とする速度検出装置に関す
る。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a speed detection device, and particularly to a speed detection device that targets a moving object that has a high speed and a large change in speed.
従来、移動物体の速度を検出する速度検出装置は、通常
移動物体にマイクロ波を発射し、その反射波の周波数の
ドツプラシフト量から速度を算出していた。しかしなが
ら、マイクロ波は発射後、波長と出射径に応じた回折に
よる拡がりを有するため、発射源から少し離れた所では
大きく拡がってしまい、目標とする物体以外にも照射さ
れる。Conventionally, speed detection devices that detect the speed of a moving object usually emit microwaves to the moving object and calculate the speed from the Doppler shift amount of the frequency of the reflected wave. However, after the microwave is emitted, it spreads due to diffraction depending on the wavelength and emission diameter, so it spreads significantly at a distance from the emission source, and it irradiates objects other than the target object.
従って、受信する反射波は異なる速度の物体からの反射
の合成されたものとり、小さな移動物体に対しては、正
確な測定が出来なくなる。近時、このような欠点を除く
ため、周波数の極めて高い電磁波としての光を用いて、
回折による拡がりを少なくし、目標とする物体のみを照
射する方法が用いられている。Therefore, the received reflected waves are a combination of reflections from objects having different speeds, and accurate measurements cannot be made for small moving objects. Recently, in order to eliminate such drawbacks, light in the form of extremely high frequency electromagnetic waves has been used to
A method is used that reduces the spread due to diffraction and irradiates only the target object.
上述した従来の光による速度検出装置は、マイクロ波等
を利用した装置に比べ拡がり角が少なくなり、目標のみ
を照射出来るという利点を有するものの、半面以下の欠
点も有しており、速度変化の激しい物体の速度検出を行
なうことは困難であるという欠点がある。Although the above-mentioned conventional speed detection device using light has the advantage of having a smaller divergence angle and being able to irradiate only the target compared to devices using microwaves, etc., it also has some disadvantages, such as the difficulty in detecting speed changes. The disadvantage is that it is difficult to detect the velocity of violent objects.
すなわち、ドツプラシフトの周波数は、物体の移動速度
と波の速度（光速）との比に波の周波数を乗じたもので
あり、周波数の高い電磁波即ち光を用いるとドツプラシ
フトによる周波数もそれに応じて高くなる。このよな高
い周波数での信号処理は困難であり、低速の移動物体用
としては実用化されているものの高速移動物体の速度検
出には不適当である。In other words, the frequency of the Doppler shift is the ratio of the moving speed of the object to the speed of the wave (speed of light) multiplied by the frequency of the wave, and if electromagnetic waves with a high frequency, that is, light, are used, the frequency due to the Doppler shift will increase accordingly. . Signal processing at such a high frequency is difficult, and although it has been put into practical use for low-speed moving objects, it is inappropriate for speed detection of high-speed moving objects.
一方、高速移動物体の速度を検出するために、光を変調
して（ドツプラシフトを考える上では光検波器出力の周
波数即ち変調周波数にて扱える）測定する方法も考えら
れているが、現状では光を外部変調する周波数に上限が
あり、この周波数で変調した光によるドツプラシフト量
は小さくなり過ぎるため、この場合は遅い速度の物体の
速度検出が困難となり、従って、遅い速度から急激に加
速されて行く物体の時々刻々の速度検出を行なう事は出
来ない。On the other hand, in order to detect the speed of a high-speed moving object, a method has been considered in which light is modulated (when considering Doppler shift, it can be handled at the frequency of the photodetector output, that is, the modulation frequency); There is an upper limit to the frequency at which the light is externally modulated, and the amount of Doppler shift due to light modulated at this frequency becomes too small.In this case, it becomes difficult to detect the speed of a slow-speed object, and therefore the object is rapidly accelerated from a slow speed. It is not possible to detect the velocity of an object from moment to moment.
本発明の速度検出装置は、光発生源と、この光発生源の
出力光を変調信号で変調して光変調光を発生する光変調
器と、前記光変調光を移動物体に送出しその反射光を受
光する送受信光学系と、前記送受信光学系によって受光
した反射光を検波する光検波器と、前記変調信号と僅か
に周波数の異る副信号を出力する副信号発生器と、前記
光検波器の出力と副信号発生器の出力とを混合してその
差周波数の信号を出力する混合器と、前記混合器の出力
のゼロクロス点間の時間を計測用クロ・ツクパルスで計
測するパルス計数器と、前記変調信号と前記計測用クロ
ックパルスを出力する基準信号発生器と、前記パルス計
数器の計数した前記混合器の出力のゼロクロス点間の計
測用クロックパルスのカウント値を記憶しつつ前記カウ
ント値にもとづいて前記ゼロクロス点間の時間を算出し
前記移動物体の速度ならびに速度変化を得る記憶回路と
を備えて構成される。The speed detection device of the present invention includes a light generation source, a light modulator that modulates the output light of the light generation source with a modulation signal to generate light modulation light, and a light modulation device that sends the light modulation light to a moving object and reflects the light. a transmitting and receiving optical system that receives light; a photodetector that detects the reflected light received by the transmitting and receiving optical system; a subsignal generator that outputs a subsignal having a slightly different frequency from the modulated signal; and the photodetector. a mixer that mixes the output of the generator and the output of the sub-signal generator and outputs a signal of the difference frequency; and a pulse counter that measures the time between zero-crossing points of the output of the mixer using a clock pulse for measurement. and a reference signal generator that outputs the modulation signal and the measurement clock pulse, and the counting while storing the count value of the measurement clock pulse between the zero crossing points of the output of the mixer counted by the pulse counter. and a memory circuit that calculates the time between the zero crossing points based on the values and obtains the speed and speed change of the moving object.
次に図面を参照して本発明の詳細な説明する。 Next, the present invention will be described in detail with reference to the drawings.
第１図は本発明の一実施例の構成図であり、光源として
の光発生源１、光発生源１の出力光を変調信号で変調し
て光変調光を発生する光変調器２、前述した変調信号を
発生する基準信号発生器３、光調変光器２の出力する光
変調光を移動物体５に送出しその反射光を受光する送受
信光学系４、送受信光学系４によって受光した反射光を
検波する光検波器６、上述した変調信号と代かに周波数
の異る副信号を出力する副信号発生器８、光検波器６の
出力と副信号発生器８の出力とを混合してその差周波数
の信号を出力する混合器７、前記混合器７の出力のゼロ
クロス点間の時間を上述した変調信号とともに基準信号
発生器３の出力する計測用クロックパルスで計測するパ
ルス計数器９、パルス計数器９の計数した混合器７の出
力のゼロクロス点間の計測用クロックパルスのカウント
値を記憶しつつこのカウント値にもとづいて上述したゼ
ロクロス点間の時間を算出し移動物体５の速度ならびに
速度変化を得る記憶回路１０を備えて構成される。FIG. 1 is a configuration diagram of an embodiment of the present invention, in which a light source 1 as a light source, an optical modulator 2 that modulates the output light of the light source 1 with a modulation signal to generate optically modulated light, and the aforementioned optical modulator 2 are shown. a reference signal generator 3 that generates a modulated signal, a transmitting/receiving optical system 4 that transmits the modulated light output from the optical modulator 2 to a moving object 5 and receives the reflected light, and a reflection received by the transmitting/receiving optical system 4. A photodetector 6 that detects light, a sub-signal generator 8 that outputs a sub-signal with a different frequency instead of the above-mentioned modulation signal, and a sub-signal generator 8 that mixes the output of the photo-detector 6 and the output of the sub-signal generator 8. a pulse counter 9 that measures the time between zero-crossing points of the output of the mixer 7 using the measurement clock pulse output from the reference signal generator 3 together with the above-mentioned modulation signal; , while storing the count value of the measurement clock pulse between the zero-crossing points of the output of the mixer 7 counted by the pulse counter 9, and calculating the time between the above-mentioned zero-crossing points based on this count value, and calculating the speed of the moving object 5. It also includes a memory circuit 10 for obtaining speed changes.
次に、第１図の実施例の動作について説明する。Next, the operation of the embodiment shown in FIG. 1 will be explained.
光発生源１から出た光１０１は、基準信号発生器３から
出力する正弦波の変調出力信号１０２により変調され、
光変調器２から振幅変調された光変調光１０３として出
光される。Light 101 emitted from the light source 1 is modulated by a sinusoidal modulated output signal 102 output from the reference signal generator 3,
The light is output from the light modulator 2 as amplitude-modulated light 103.
振幅変調された光変調光１０３は送受信光学系４により
外部に出力光１０９として出射され、移動物体５に当た
り反射する。反射の際に移動物体の速度に比例したドツ
プラシフトを受けて変調周波数が変化した反射光１０４
は送受信光学系４により受光され光検波器６に入射し、
反射光１０４の変調層割数に応じ、な検波信号１０５が
出力され混合器７に入力する。The amplitude-modulated light 103 is emitted to the outside as output light 109 by the transmitting/receiving optical system 4, hits the moving object 5, and is reflected. Reflected light 104 whose modulation frequency has changed due to a Doppler shift proportional to the speed of the moving object upon reflection.
is received by the transmitting/receiving optical system 4 and enters the optical detector 6,
A detection signal 105 is outputted according to the modulation layer division number of the reflected light 104 and inputted to the mixer 7.
混合器７は、基準信号発生器３と僅に異る数ＫＨｚの周
波数差の信号１０６を発生する副信号発生器８からの副
信号１０６と検波信号１０５を混合し、二つの信号の差
の周波数の差周波数信号１０７を出力する。The mixer 7 mixes the detected signal 105 with the sub-signal 106 from the sub-signal generator 8 which generates a signal 106 with a frequency difference of several KHz slightly different from that of the reference signal generator 3, and calculates the difference between the two signals. A frequency difference frequency signal 107 is output.
差周波数信号１０７は、従って、副信号１０６−（変調
信号１０２＋ドツプラシフト）の周波数となる。ただし
、本実施例にあっては、副信号１０６の周波数を変調信
号１０２の周波数よりも高いものとしているが、その逆
の設定でも勿論差し支えない。The difference frequency signal 107 therefore has the frequency of the sub-signal 106-(modulation signal 102+Doppler shift). However, in this embodiment, the frequency of the sub-signal 106 is set higher than the frequency of the modulation signal 102, but of course the opposite setting is also possible.
この差周波数信号１０７はパルス計数器９に供給される
。この差周波数信号はほぼ数ＫＨ２の正弦波信号であり
、パルス計数器９は、この差周波数信号のゼロクロス点
間の時間を基準信号発生器３から得られる計測用クロッ
クパルス１０８で計測し、このゼロクロス点間ごとに得
られる計測用クロックパルス１０８のカウント値を記憶
回路１０に供給する。This difference frequency signal 107 is supplied to a pulse counter 9. This difference frequency signal is a sine wave signal of approximately several KH2, and the pulse counter 9 measures the time between zero crossing points of this difference frequency signal using the measurement clock pulse 108 obtained from the reference signal generator 3. The count value of the measurement clock pulse 108 obtained between zero crossing points is supplied to the storage circuit 10.
第２図（ａ）は第１図の実施例におけるゼロクロス点間
のパルス計数の説明図、第２図（ｂ）は第１図の実施例
におけるゼロクロス点間のパルス計数の記憶内容の説明
図である。FIG. 2(a) is an explanatory diagram of pulse counting between zero-crossing points in the embodiment of FIG. 1, and FIG. 2(b) is an explanatory diagram of memory contents of pulse counting between zero-crossing points in the embodiment of FIG. 1. It is.
第２図＜ａ）に示す如く、本実施例では、ゼロクロス点
として差周波数信号１０７がプラスの勾配でゼロライン
を切る点１．，１．を利用しているが、これはマイナス
の勾配も含む全ゼロクロス点を利用しても勿論差し支え
ない。As shown in FIG. 2 <a), in this embodiment, the zero crossing point is the point 1. where the difference frequency signal 107 crosses the zero line with a positive slope. ,1. However, it is of course possible to use all zero crossing points including negative slopes.
ゼロクロス点ｔ、とｔｎ間の時間は計測用クロックパル
ス１０８のカウントから容易に知ることができる。The time between zero cross points t and tn can be easily determined from the count of the measurement clock pulses 108.
記憶回路１０は、パルス計数器９がら提供されるゼロク
ロス点間のパルス計数値を記憶しっ、これにもとづいて
ゼロクロス点間の時間を求める。The memory circuit 10 stores the pulse count value between zero-crossing points provided by the pulse counter 9, and calculates the time between zero-crossing points based on this.
このゼロクロス点間の時間は、明らかに移動物体５の速
度に従って変化し、また速度の変化に対応して変化する
。The time between these zero-crossing points clearly changes according to the speed of the moving object 5, and also changes in response to changes in speed.
第２図（ｂ）のｎｌ、ｎ２．ｎ３は計測器間のゼロクロ
ス点ごとのパルス計測数を示す。ゼロクロス点間の時間
は差周波数信号１０７の逆数であり、光を反射した移動
物体５が静止していればこの時間（パルス計測数ｎ）は
一定であるが、移動している場合は移動速度に応じて差
周波数信号１０７の周波数が低く（ゼロクロス点間の時
間が長く）なり、パルス計測数ｎが変化（増加）する。nl, n2 in FIG. 2(b). n3 indicates the number of pulses measured at each zero crossing point between the measuring instruments. The time between zero cross points is the reciprocal of the difference frequency signal 107, and if the moving object 5 that reflected the light is stationary, this time (pulse measurement number n) is constant, but if it is moving, the moving speed Accordingly, the frequency of the difference frequency signal 107 becomes lower (the time between zero crossing points becomes longer), and the pulse measurement number n changes (increases).
なお第２図（ｂ）は分かり易くするために誇張して書い
たが実際はこのように大きな変化ではない。本実施例で
は、ゼロクロス点間の時間は０．１ミリ秒のオーダーで
あり、このゼロクロス点間の時間ごとの平均速度に対応
したデータが記憶回路１０・に記憶されることとなるの
で、この結果をデータ処理を行なって速度変化の激いし
い物体についても時々刻々の速度計測が可能となり、ま
た更にデータ処理を行なって時々刻々の位置情報を得る
ことも可能となる。Although Fig. 2(b) is exaggerated for clarity, the change is actually not this big. In this embodiment, the time between zero-crossing points is on the order of 0.1 milliseconds, and data corresponding to the average speed for each time between zero-crossing points is stored in the storage circuit 10. Data processing of the results makes it possible to measure the velocity of an object whose velocity changes rapidly from moment to moment, and further data processing makes it possible to obtain moment-to-moment position information.
第３図（ａ）は第１図の実施例の記憶回路１０における
計数パルス数の一例を示す特性図で、ゼロクロス点ごと
の移動物体の計測パルス数の一例を示している。FIG. 3(a) is a characteristic diagram showing an example of the number of pulses counted in the memory circuit 10 of the embodiment shown in FIG. 1, and shows an example of the number of pulses measured for a moving object at each zero-crossing point.
また、第３図（ｂ）は第３図（ａ）の計測パルス数に対
応して得られる移動物体の算出速度の特性図、第３図（
ｃ）は第３図（ｂ）の算出速度にもとづいて得られる移
動物体の位置の特性図である。In addition, FIG. 3(b) is a characteristic diagram of the calculated velocity of the moving object obtained corresponding to the number of measured pulses in FIG. 3(a), and FIG.
c) is a characteristic diagram of the position of a moving object obtained based on the calculated velocity of FIG. 3(b).
次に、本実施例に関して具体的な数値例を挙げて説明す
る。Next, the present embodiment will be explained using specific numerical examples.
いま、
基準信号発生器３の変調信号の周波数１００）４１−ｉ
ｚ副信号発生器８の副信号の周波数１００．００５Ｍ）
（ｚ移動物体５の速度 １０００ｍ／
Ｓ光速度 ３０００００Ｋｍ／Ｓと
すると速度零の時の差周波数＝１０００５０００−１０
０００００００＝ ５０００１−１ｚであり、１周期の
時間＝２００μＳとなる。Now, the frequency of the modulation signal of the reference signal generator 3 100) 41-i
Frequency of sub signal of z sub signal generator 8: 100.005M)
(z Speed of moving object 5 1000m/
S If the speed of light is 300000 Km/S, the difference frequency when the speed is zero = 10005000-10
0000000=50001-1z, and the time of one cycle=200 μS.
１０ＭＨｚ即ち１０ｎＳごとのクロックで２０００カウ
ントに対し、
移動物体５の速度１０００＋ｎ／Ｓの場合、ドツプラシ
フト＝ １０００ｍ／Ｓ÷３００００００００ｍ／５Ｘ
１００００００００Ｈｚ ＝ ３３３．３３３３３Ｆｌ
ｚ速度１０００ｍ／Ｓの時の反射波の変調周波数は、１
０００００３３３．３３３３３）１ｚ差の周波数＝ １
００００５０００Ｈｚ −１０００００３３３，３３３
３３Ｈｚ ＝ ４６６６ 、６６６６６Ｈｚ１周期の時
間＝ ２１４．２８６μｓ
１００ＭＨｚ即ち１０ｎＳ毎のクロックで２１４２８ま
たは２１４２９カウント
速度Ｏの時のカウントとの差は１４２８又は１４２９カ
ウント
分解能を考えると、２ｍ／Ｓでは
ドツプラシフト−２ｍ／Ｓ÷３００００００００ｍ／Ｓ
Ｘ １００００００００Ｈ，ｚ ＝ 、６６６６６Ｈｚ
速度２ｍ／Ｓの時の反射波の変調周波数は、１００００
．００００．６６６６６ｔ（ｚ差の周波数＝ １０００
０５０００Ｈｚ −１００００００００，６６６６６Ｈ
ｚ＝ ４９９９．３３３３３Ｈｚ
１周期の時間＝ ２００．０２６７μ５１００＋ｎ）４
Ｈｚ即ち１０ｎＳ毎のクロックで２０００２又は２００
０３カウントとなり、速度０の場合と識別可能となる。If the speed of the moving object 5 is 1000+n/S for 2000 counts with a clock every 10MHz or 10nS, then Doppler shift = 1000m/S ÷ 300000000m/5X
100000000Hz = 333.33333Fl
The modulation frequency of the reflected wave when the z speed is 1000 m/s is 1
00000333.33333) 1z difference frequency = 1
00005000Hz -100000333,333
33Hz = 4666, time for one cycle of 66666Hz = 214.286μs At 100MHz, that is, a clock every 10nS, the difference from the count when the count speed is O is 1428 or 1429. Considering the count resolution, at 2m/S, Doppler shift - 2m/ S÷300000000m/S
X 100000000H,z = , 66666Hz The modulation frequency of the reflected wave at a speed of 2m/S is 10000
．． 0000.66666t (z difference frequency = 1000
05000Hz -100000000,66666H
z = 4999.33333Hz Time of one cycle = 200.0267μ5100+n)4
20002 or 200 with a clock every 10nS
03 count, which can be distinguished from the case where the speed is 0.
即ち２ｍ／Ｓの分解能が得られる。That is, a resolution of 2 m/s can be obtained.
以上説明したように本発明は、移動物体からの反射によ
るドツプラシフト周波数を直接計測せず、適当な周波数
差を有する副信号とドツプラシフト分含む反射信号との
差信号を利用することにより測定し易い周波数に変換し
、その際、ゼロクロス点間の時間を移動物体の速度変化
に応じて最適な時間に設定し、全てのゼロクロス点間の
時間を基準周波数のパルスの計数値として記憶すること
により、高速度の移動物体の時々刻々速度変化を正確に
かつ速度変化に忠実に対応して測定を行なうことが出来
るという効果がある。As explained above, the present invention does not directly measure the Doppler shift frequency due to reflection from a moving object, but uses the difference signal between the sub signal having an appropriate frequency difference and the reflected signal including the Doppler shift, to easily measure the frequency. Converting to This has the advantage that it is possible to measure moment-to-moment changes in speed of a moving object accurately and faithfully corresponding to the changes in speed.
第１図は本発明の速度検出装置の一実施例の構成図、第
２図（ａ）は第１図の実施例のおけるゼロクロス点間の
パルス計数の説明図、第２図（ｂ）は第１図の実施例に
おけるゼロクロス点間のパルス計数の記憶内容の説明図
、第３図（ａ）は第１図の実施例の記憶回路１０におけ
る計数パルス数の一例を示す特性図、第３図（ｂ）は第
３図（ａ）の計測パルス数に対応して得られる移動物体
の算出速度の特性図、第３図（Ｃ）は第３図（ｂ）の算
出速度にもとづいて得られる移動物体の位置の特性図で
ある。
１・・・光発生源、２・・・光変調器、３・・・基準信
号発生器、４・・・送受信光学系、５・・・移動物体、
６・・・光検波器、７・・・混合器、８・・・副信号発
生器、９・・・パルス計数器、１０・・・記憶回路、１
０１・・・光、１０２・・・変調信号、１０３・・・光
変調光、１０４・・・反射光、１０５・・・検波信号、
１０６・・・副信号、１０７・・・差周波数信号、１０
８・・・計測用クロックパルス、１０９・・・出力光。
＾ ７ 図Figure 1 is a block diagram of an embodiment of the speed detection device of the present invention, Figure 2 (a) is an explanatory diagram of pulse counting between zero cross points in the embodiment of Figure 1, and Figure 2 (b) is 3(a) is a characteristic diagram showing an example of the number of counted pulses in the storage circuit 10 of the embodiment of FIG. 1; FIG. Figure (b) is a characteristic diagram of the calculated velocity of a moving object obtained in response to the number of measured pulses in Figure 3 (a), and Figure 3 (C) is a characteristic diagram obtained based on the calculated velocity in Figure 3 (b). FIG. 3 is a characteristic diagram of the position of a moving object. DESCRIPTION OF SYMBOLS 1... Light generation source, 2... Optical modulator, 3... Reference signal generator, 4... Transmission/reception optical system, 5... Moving object,
6... Photodetector, 7... Mixer, 8... Sub-signal generator, 9... Pulse counter, 10... Memory circuit, 1
01... Light, 102... Modulated signal, 103... Light modulated light, 104... Reflected light, 105... Detected signal,
106... Sub signal, 107... Difference frequency signal, 10
8... Clock pulse for measurement, 109... Output light. ＾ 7 Figure
Claims (1)
て光変調光を発生する光変調器と、前記光変調光を移動
物体に送出しその反射光を受光する送受信光学系と、前
記送受信光学系によつて受光した反射光を検波する光検
波器と、前記変調信号と僅かに周波数の異る副信号を出
力する副信号発生器と、前記光検波器の出力と副信号発
生器の出力とを混合してその差周波数の信号を出力する
混合器と、前記混合器の出力のゼロクロス点間の時間を
計測用クロックパルスで計測するパルス計数器と、前記
変調信号と前記計測用クロックパルスを出力する基準信
号発生器と、前記パルス計数器の計数した前記混合器の
出力のゼロクロス点間の計測用クロックパルスのカウン
ト値を記憶しつつ前記カウント値にもとづいて前記ゼロ
クロス点間の時間を算出し前記移動物体の速度ならびに
速度変化を得る記憶回路とを備えて成ることを特徴とす
る速度検出装置。A light generation source, an optical modulator that modulates the output light of the light generation source with a modulation signal to generate modulated light, and a transmitting/receiving optical system that transmits the modulated light to a moving object and receives the reflected light. , a photodetector that detects the reflected light received by the transmitting/receiving optical system, a sub-signal generator that outputs a sub-signal having a slightly different frequency from the modulation signal, and an output of the photo-detector and the sub-signal. a mixer that mixes the output of the generator and outputs a signal of the difference frequency; a pulse counter that measures the time between zero-crossing points of the output of the mixer using a measurement clock pulse; The count value of the measurement clock pulse between the reference signal generator that outputs the measurement clock pulse and the zero-cross point of the output of the mixer counted by the pulse counter is stored, and the zero-cross point is determined based on the count value. 1. A speed detection device comprising: a storage circuit that calculates the time between and obtains the speed and speed change of the moving object.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63176642A JPH083529B2 (en) | 1988-07-14 | 1988-07-14 | Speed detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63176642A JPH083529B2 (en) | 1988-07-14 | 1988-07-14 | Speed detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0225786A true JPH0225786A (en) | 1990-01-29 |
| JPH083529B2 JPH083529B2 (en) | 1996-01-17 |
Family
ID=16017150
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63176642A Expired - Lifetime JPH083529B2 (en) | 1988-07-14 | 1988-07-14 | Speed detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH083529B2 (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2757953A1 (en) * | 1996-12-26 | 1998-07-03 | Nec Corp | Line of Sight Speed Measurement Apparatus for Moving Objects |
| WO2004074867A1 (en) * | 2003-02-19 | 2004-09-02 | Mitsubishi Denki Kabushiki Kaisha | Laser radar |
| US7209222B2 (en) | 2002-12-27 | 2007-04-24 | Mitsubishi Denki Kabushiki Kaisha | Laser radar apparatus |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS578273A (en) * | 1980-06-19 | 1982-01-16 | Dainippon Printing Co Ltd | Adhesive composition for laminate |
-
1988
- 1988-07-14 JP JP63176642A patent/JPH083529B2/en not_active Expired - Lifetime
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS578273A (en) * | 1980-06-19 | 1982-01-16 | Dainippon Printing Co Ltd | Adhesive composition for laminate |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2757953A1 (en) * | 1996-12-26 | 1998-07-03 | Nec Corp | Line of Sight Speed Measurement Apparatus for Moving Objects |
| US7209222B2 (en) | 2002-12-27 | 2007-04-24 | Mitsubishi Denki Kabushiki Kaisha | Laser radar apparatus |
| WO2004074867A1 (en) * | 2003-02-19 | 2004-09-02 | Mitsubishi Denki Kabushiki Kaisha | Laser radar |
| US7274437B2 (en) | 2003-02-19 | 2007-09-25 | Mitsubishi Denki Kabushiki Kaisha | Laser detection and ranging apparatus |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH083529B2 (en) | 1996-01-17 |
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