JP6233606B2 - Target identification laser observation system - Google Patents

Description

  The present invention relates to a laser observation system for observing a flying object.

  Nowadays, laser light is used for various purposes. A typical laser observation system is a laser ranging system. For example, a laser observation system for observing an artificial satellite equipped with a reflector is called SLR (Satellite Laser Ranging).

  In SLR, it is possible to accurately measure the distance from a laser beam launch point to an artificial satellite (reflector). By observing the exact position of the satellite at many points, the observation system can derive the precise orbit of the satellite. As a result, this artificial satellite can be used as a triangular point in orbit in various systems.

An example of a laser observation system is described in Patent Document 1, for example.
The laser observation system (moving body position measuring device) described in Patent Document 1 is a laser device (optical device) that continuously irradiates a target with laser pulse light and receives reflected laser light reflected by the target. It comprises. In this radar observation system, the target is measured by each of the continuously transmitted laser pulse lights, and each reflected laser pulse light is detected by the array sensor, and the moving direction is derived from the difference between the detection positions. This document also discloses a mechanism for automatically matching the direction in which the laser pulse light is transmitted to the target.

  For the automatic tracking technique, for example, a radar observation system described in Patent Document 2 is a reference. Patent Document 2 discloses a method for automatically tracking a target flying at high speed, such as a rocket or debris, with high accuracy. Although Patent Document 2 describes a radar observation technique, it can be incorporated as one of automatic tracking techniques for radar observation by re-reading the antenna direction as the telescope direction.

  Patent Document 3, Patent Document 4 and Patent Document 5 describe a method for identifying a target object from a radar image or a still image. Patent Document 6 describes an apparatus for narrowing down a target object using a model pattern. Patent Document 7 discloses an information processing apparatus (group) that tracks a target in cooperation between a plurality of apparatuses connected via a network.

JP 2009-244192 A JP 2011-112494 A JP 2000-275338 A JP 2004-093166 A JP 2007-207180 A JP 2010-210212 A Japanese Patent Laying-Open No. 2015-068545

  The laser observation system can be used for various applications. For example, the laser observation technique described in Patent Document 1 can be used for many observation applications such as flying objects, rockets, and space debris (hereinafter referred to as debris) flying in outer space.

  The flying object observation method includes an optical observation method using a camera and a radar observation method using radio waves.

Debris observation will be used as an example to explain the problems of these flight observation techniques.
In debris observation, we would like to observe the state of debris shape, rotational motion, etc. accurately in order to finally use it for debris removal.
Since the former optical observation often observes reflected sunlight, there is a problem that it cannot be observed in the state where sunlight does not strike. In optical observation, only the angle of view of the camera is observed, and the distance cannot be calculated. As a result, the debris trajectory cannot be determined. Furthermore, in optical observation, there is a limit to the size of the telescope (optical system) to accurately identify debris flying at a high altitude from the ground.
The latter radar observation is inferior in resolution for identifying a target object compared to optical observation and laser observation. As a result, accurate orbit determination and object identification with the required accuracy are difficult only by radar observation.

  Several problems can also be set for the laser observation technique disclosed in Patent Document 1, and improvement of target capturing ability and target identifying ability can be studied. More specifically, in the laser observation technique disclosed in Patent Document 1, it is required that the reflected laser pulse light returns from the target at a level higher than a predetermined value. Further, it is required that the reflected laser pulse light returns from the target in the form of a pulse without breaking the waveform. This is unlikely to be a problem for targets that maintain a good reflective surface (for example, an artificial satellite equipped with a reflector), an object flying in a stable posture, an object with a good reflective surface, etc. Not all goals are such characteristics. For example, it has unsuitable side surfaces such as debris that is constantly rotating, an object that causes strong scattering on the reflecting surface, and an object that has a surface that hardly reflects a specific wavelength.

  Further, the laser observation technique disclosed in Patent Document 1 aims at obtaining the position and distance of the target object, and does not identify the target itself. The techniques described in Patent Documents 2 to 7 are not laser observation techniques.

  The present invention has been made to solve some of the above-described problems, and an object of the present invention is to provide a target identification laser observation system that satisfactorily identifies a target object with laser light.

  Another object of the present invention is to provide a target identification laser observation system that can satisfactorily track a target object.

A target identification laser observation system according to an embodiment of the present invention includes a telescope that is directed to an initially captured target object, a laser device that receives pulsed laser light that is scattered and deformed by the target object via the telescope, A waveform acquisition unit that acquires the waveform shape of the deformed pulse laser beam and the amount of change in the waveform shape, and at least the surface of the target object based on the light-receiving waveform shape of the deformed pulse laser beam and the amount of change in the waveform shape And a determination unit that performs an object identification that reflects the estimation result by performing a shape estimation process.

A laser target identification method using a lidar system according to an embodiment of the present invention includes a laser emitting step of irradiating an initially captured target object with laser pulse light of one or a plurality of wavelengths, and a telescope directed to the initially captured target object. A laser light receiving step for condensing one or a plurality of pulsed laser beams having been scattered and deformed by a target object via one or more observation points, a waveform shape of the pulse laser light condensed in the laser light receiving step, and A waveform acquisition step for acquiring a change amount of the waveform shape, and a received light waveform shape acquired in the waveform acquisition step and a surface shape of the target object estimated based on the change amount of the waveform shape, or a surface shape of the target object And a target identification step of performing object identification reflecting the estimation result based on the past observation result.

  ADVANTAGE OF THE INVENTION According to this invention, the target identification laser observation system which identifies a target object favorably with a laser beam can be provided.

  Similarly, according to the present invention, it is possible to provide a target identification laser observation system that can satisfactorily track a target object.

1 is a block diagram showing a laser observation system according to a first embodiment of the present invention. It is explanatory drawing which showed the operation | movement aspect of the laser observation system of 1st Embodiment for the example of debris observation. It is explanatory drawing which showed the operation | use aspect which uses multiple wavelengths with the laser observation system of 1st Embodiment. It is explanatory drawing which modeled the change of the receiving pulse width when the reflected wave of a target object is received in the several measurement point using the laser pulse light of single frequency. FIG. 5 is an explanatory diagram schematically illustrating a change in a reception pulse width when a reflected wave of a target object is received at a plurality of measurement points using laser pulse light in a state where the angle of the target object in FIG. 4 is changed. It is explanatory drawing which showed typically the relationship between an irradiation pulse wave and a condensing pulse wave. It is explanatory drawing which showed the structure and the operation | movement aspect of the laser observation system 2 of 2nd Embodiment which concern on this invention. 2 is a block diagram illustrating an internal structure of a laser device 10. FIG. It is the block diagram which illustrated the internal structure of the laser apparatus 10 incorporating the heterodyne system.

A plurality of embodiments of the present invention will be described with reference to the drawings.
The laser observation system described using the embodiment includes a mechanism for transmitting laser pulse light toward a target and receiving reflected laser light as a reflected wave, similarly to the existing laser ranging system. The initial capture of the target object may be performed by referring to a database in which the trajectory of the target object is recorded in advance, or by constantly capturing the coordinates at which the target object appears. Further, the initial acquisition may be performed using one or both of the radar observation method and the optical observation method.

  In the following description, descriptions of similar parts between the embodiments are simplified or omitted. Further, in the following description, a ranging method based on a difference (time) between the transmission timing of the pulse laser beam and the light reception timing is simplified or omitted. Of course, each laser observation system should be configured so that the distance to the target can be measured.

FIG. 1 is a block diagram showing a laser observation system 1 according to the first embodiment.
FIG. 2 is an explanatory diagram showing an operation mode of the laser observation system 1 taking debris observation as an example. FIG. 2A shows a state where the observation target debris is aimed, and FIG. 2B schematically shows an example of a received waveform change of the laser pulse.

  FIG. 3 schematically shows an example of a received waveform change of a laser pulse in an operation mode using a plurality of wavelengths.

  As shown in the figure, the laser observation system 1 includes a laser device 10, a control unit 20 (a waveform acquisition unit 21, a determination unit 22), and a telescope 30.

  The laser device 10 includes a mechanism for generating pulsed laser light and sending it to a target, and a mechanism for condensing reflected laser light scattered by the target. The laser device 10 is preferably configured so that the pulsed laser light to be transmitted can be continuously transmitted with an extremely short time interval. Further, the laser device 10 is preferably configured to be capable of changing the wavelength of the pulsed laser light. The wavelength can be changed by changing the laser medium itself to be generated, or may be changed by a wavelength conversion element or the like. As will be described later, it is not always necessary to send the pulsed laser beam to the target at all observation points (light receiving points), and it may be configured as a laser observation system that performs only observation (light reception).

  For example, the laser apparatus 10 includes a laser controller, a laser oscillator, an optical system path, and a light receiving sensor (light detector). Further, a spectroscope, a filter, an optical amplifier, an electric signal amplifier, a distance measuring counter, etc. may be provided as necessary. In the laser apparatus 10, the laser controller receives a laser control signal from the control unit 20, the laser controller operates a laser oscillator, and sends a transmission laser beam (pulse laser beam) from the optical system path to the telescope 30. Immediately thereafter, the laser device 10 converts the reflected laser light (deformed pulse laser light) sent from the telescope 30 into a signal by the light receiving sensor via the optical system path. This waveform signal is transmitted to the waveform acquisition unit 21. When performing distance measurement, the laser device 10 also notifies the control unit 20 of the time (time information) from the transmission of the transmitted laser light to the reception of the reflected laser light. The waveform signal may be digitized and notified to the control unit 20 as a digital signal, or may be notified as an analog signal.

  The control unit 20 manages the overall operation of the laser observation system 1 in an integrated manner. For example, time management, generation timing of the transmitted pulse laser beam, adjustment of the angle of the telescope 30, distance measurement, communication with other systems, and the like are managed. The control unit 20 includes a waveform acquisition unit 21 and a determination unit 22. A distance measuring unit, a communication unit, and the like may be provided as necessary. The communication unit may communicate with the communication partner through a necessary communication interface, regardless of wired / wireless.

  The control unit 20 acquires a waveform signal and time information from the laser device 10 in accordance with object identification processing (such as trajectory determination and shape identification) of a desired target countermeasure object, and past observation data and predicted trajectory as necessary. Then, the target coping object and its state are accurately discriminated using a database or the like that records the characteristics of the target coping object.

  When the automatic tracking function is provided, the control unit 20 receives the input of orbit information (position, velocity, etc.) and automatically controls the angle of the telescope 30 and the reflected wave by the array sensor or the like in the laser device 10. It is desirable to provide autonomous tracking that automatically calculates and tracks the target moving direction from the received light results.

  The waveform acquisition unit 21 acquires the waveform of the reflected laser beam. Here, the description will be made on the assumption that the reflected laser light is converted into an electric signal in the laser device 10. In addition, it is good also as a structure which receives in the state of an optical signal from the laser apparatus 10, and acquires the waveform of reflected laser light.

  Further, it is desirable that the waveform acquisition unit 21 is configured to acquire the waveform of the reflected laser light separately for each wavelength of the laser light when acquiring the waveform of the reflected laser light. Many objects exhibit different characteristics in reflection characteristics for each wavelength depending on the surface state. This difference in reflection characteristics for each wavelength is used for discrimination of object identification by observing a waveform divided for each wavelength.

  Moreover, it is desirable that the waveform acquisition unit 21 includes a mechanism for digitizing the change along with the waveform shape of the reflected light (condensed scattered light). The time change of the reflected light waveform represents the physical depth (shape) of the reflecting surface. The relative change in the reflected light intensity represents the reflection characteristics of the surface state and the area of the reflecting surface. It is desirable that these changes be able to quantify both the amount of change in a group of reflected light and the amount of change in the transmitted laser waveform and reflected laser waveform.

  Further, it is desirable that the waveform acquisition unit 21 includes a mechanism for quantifying the change in the waveform shape of the transmitted laser beam (pulse laser beam) together with the reflected laser beam. It is desirable that the transmitted laser light be configured so that the waveform shape can be acquired for each wavelength and the shape of the synthesized wave can also be acquired.

  The determination unit 22 performs object identification from the light receiving waveform shape of the reflected laser light. Object identification may be performed by appropriately combining a target surface state (material estimation) using a waveform change rate, general object recognition by a pattern matching method, object matching within a specific candidate, and the like. For example, it is assumed that an object that is line-symmetric when viewed from the laser device rotates around the line (when the target is tilted). At both ends farthest from the center of rotation, there is an optical path difference before and after viewing from the laser device 10 (telescope 30), and there is a difference in arrival time between reflected light from both ends. Assuming that the reflection characteristics of the surface as well as the shape are axisymmetric, the shape of the reflected light obtained is axisymmetric in time (see FIG. 6).

  A database used for pattern matching may be provided in the control unit 20 or may be referred to a database located at a remote location via a communication line. It is desirable that both databases be configured so that they can be used as appropriate. In this database, data that correlates the received light waveform shape of scattered light (reflected laser light) and identification target object candidates are stored, and the size, reflection characteristics, current estimated posture, etc. of the identification target object are appropriately recorded. That's fine.

  The telescope 30 has an optical system path, is optically connected to the optical system path of the laser device 10, and is used to direct at least a focused light path to a target object. The telescope 30 preferably includes a focus adjustment mechanism and a drive mechanism. The focus adjustment mechanism and the drive mechanism operate according to instructions from the control unit 20. As the drive mechanism, it is desirable to use a biaxial or triaxial drive mechanism in order to direct the laser optical axis to the LOS (Line of Sight) angle of the target position.

  The laser observation system 1 having such a configuration is operated in the following order to execute object identification. Here, the order of the laser target identification method will be briefly described with reference to FIG.

1. Laser emission process: Irradiate laser pulse light (A) in Fig. 2 toward the target
2. Laser receiving process: Condensing the deformed laser pulse light (B) in FIG.
3. Waveform acquisition process: Waveform acquisition of laser pulse light (B)
4). Object identification process: Object identification based on waveform acquisition of laser pulse light (B) The steps 1 to 4 are repeated as necessary to improve the identification accuracy. At this time, it is also possible to sequentially switch to laser beams having different wavelengths or to sequentially switch the intensity of the laser beams. Further, the ranging process using the reflected wave may be performed simultaneously. Further, the laser emission process and the laser light reception process may be performed at different points. In addition, the laser emission process may be performed at one or more observation points without performing the laser emission process in the own system. Further, as shown in FIG. 3, observation may be performed using pulsed laser beams having a plurality of wavelengths simultaneously. FIG. 3 shows an example in which two-wavelength pulsed laser light is continuously transmitted. Transmission / reception of pulse laser beams of a plurality of wavelengths is not limited to this example, and pulse laser beams of three or more wavelengths are continuously used, or pulse laser beams having different wavelengths are superimposed and transmitted (at the same timing). Also good. A plurality of pulsed laser beams having different wavelengths transmitted from different points may be observed at one or a plurality of observation points.

  In this way, by making the wavelength different, the scattering characteristics of the target object for each wavelength are reflected in the focused wave, and even if the reflected waves in each wavelength band reach the telescope at the same time, they can be easily separated. It becomes possible. For example, it is also possible to separately perform pattern matching for each collected wave having different wavelengths and pattern matching for a synthesized wave obtained by combining collected waves having several wavelengths. As a result, the possibility that more characteristic information useful for object identification can be obtained increases, and the identification ability can be improved.

  Further, the trajectory of the target object may be calculated using the distance measurement distance, the previous observation result, the predicted value, etc., and the telescope 30 may be adjusted according to the trajectory prediction to always automatically track in the optimum direction.

  By identifying the target object with the laser beam in this order, it is possible to acquire feature information that has not been acquired by the existing method related to the target object as the target observation method using the pulse laser beam.

  For example, when the target object is debris, the shape, material, rotation state, etc. of the debris can be identified with higher accuracy by comparing the received light waveform acquired from these debris with a pre-built database. Is possible. In addition, it is possible to identify the size of debris together with the distance measurement, and to perform overall matching or partial matching with known target object candidates. As a result, it is possible to distinguish from the laser beam to the material, motion, and object recognition of the target object.

  Here, an observation method for identifying an object state (size, shape, etc.) will be described with a schematic waveform as an example.

  FIG. 4 schematically shows changes in the received pulse width when receiving at a plurality of observation points using single-frequency pulsed laser light. In order to explain the change in waveform shape, a case will be described in which a single-frequency pulse laser beam transmitted from observation point 1 is observed at observation point 2 (another point) that is sufficiently far away.

  In the following method, the size of the target object is identified from the change in the pulse length. In this explanation, the rocket engine is shown as a target. However, for the purpose of explanation, when the plane plate is kept relatively stationary with a single material, how the waveform changes with the telescope at observation point 2 Explain what to do.

Each variable in the figure is as follows.
D: Projection width of target debris (unknown value)
t1: Pulse width of irradiated laser beam at observation point 1 (pulse width of received laser beam)
t2: Pulse width of focused laser beam at observation point 2 θ: Angle formed by observation point 1, target, and measurement point 2
L1: Optical path difference of scattered light generated in the target reflecting surface when viewed from observation point 2
c: speed of light
As can be mathematically determined from the illustrated relationship, the relationship between the pulse width t2 of the focused laser beam and the pulse width t1 of the irradiation laser beam can be expressed by the following equation.
t2 ≒ t1 + (L1 / c) = t1 + (D · sinθ) / c (1)
As can be understood from this relational expression, the observation point 2 is obtained by using the pulse width t2 of the focused laser beam at the observation point 2 and the angle θ between the observation point 1 and the observation point 2 with respect to the target object. The width D of the unknown target object can be estimated from the observation result of the scattered light. The width D of the target object can be similarly estimated from the observation result at the observation point 1.

  This relationship holds true even if another observation point is provided. By superimposing the estimated value of the width D of the target object and using it for estimation, a value D with high accuracy can be obtained.

  The relationship of the change of the focused pulse width with respect to the transmission pulse width is the same even when the angle of the target object changes as shown in FIG. Note that the change in the angle of the target object changes the wave height and waveform shape (wave shape) of the focused laser beam.

  In this description, the method of acquiring the feature information of the target object with respect to the angle between the scattered light and the observation point for one pulsed light has been described. In order to observe the target object with higher accuracy, it is desirable to change the irradiation pulse light to continuous pulse light and continuously observe the target object at multiple measurement points using pulse light of different wavelengths. .

  In addition, the above explanation has explained the relationship that appears in the transmitted and received laser light between observation points that are sufficiently distant from each other. It is good also as comprising.

  The extended width of the irradiation pulse laser beam is kept almost constant up to the debris reflection surface, but if the debris reflection surface is tilted or uneven, the arrival time within one irradiation pulse changes and the reflected light pulse The waveform is different from the irradiation pulse waveform. Therefore, the target is largely divided into three parts and arranged symmetrically, and the reflectances of the first wavelength and the first wavelength are opposite to each other at the two parts at the both ends of the target and the central part. In this case, the reflected light as schematically shown in FIG. 6 can be obtained according to the attitude of the debris.

  FIG. 6A schematically shows a relationship between a single-frequency irradiation pulse wave and a multi-frequency irradiation pulse wave and a focused pulse wave in FIG. 6B. As shown in FIG. 6 (b), the shapes of the received waveforms of the first wavelength and the second wavelength are common to be symmetrical with respect to time, but the intensity of the waveform at both ends and the center is reflected in the reflectance. Corresponding waveforms are produced accordingly.

  As described above, the waveform information is acquired from the reflected wave including the characteristic information of the target object by collecting the scattered light and separating it into the respective wavelengths as necessary. Feature information of the target object is extracted from this waveform information.

  Further, since the posture of many debris is not fixed, the reflecting surface on which the laser beam is rotated and becomes different in shape (size) with time.

  It is possible to accurately identify the shape of the target object by holding a database in advance with respect to the condensed waveform of the reflected laser light from these debris. With known satellite parts and rockets, the overall shape and reflectivity of the material can be prepared on the ground. Moreover, even if it is an unknown object, the shape specification can be clarified sequentially by repeated observations.

  In addition, by using laser beams having different wavelengths, changes in the intensity distribution for each wavelength can be observed at each observation point. At this time, the identification result with higher accuracy can be obtained by sequentially proceeding with the object identification in the database reflecting the current state of the target object.

  In this way, the scattered light generated on the target surface is collected by the laser observation system at a measurement point different from the irradiation point of the pulsed laser light, and the waveform shape is observed.

  Further, by irradiating one or a plurality of pulsed laser beams to the same debris (target) from a plurality of measurement points, a plurality of reception pulses are obtained at each measurement point from a plurality of transmission pulses having different incident angles. The direction of rotation of debris can be extracted more accurately.

  Furthermore, by simultaneously observing with a plurality of laser devices with different laser wavelengths to be used, the scattered light of pulsed laser light emitted from other laser devices is collected by each device, and information from a plurality of received waveforms is collected. The target shape can be derived with high accuracy.

  In addition, it is possible to detect the speed of the target object with high accuracy from the observation results of a plurality of observation points / continuous observations that collect the scattered light.

  By calculating the propagation direction of the target object from this detection result, the trajectory can be accurately estimated even for debris propagating through an unknown trajectory. As a result, accurate information can be input to the mechanism for automatic tracking, and the tracking performance can be improved.

  In this way, by observing the change in the scattered light of the pulse laser beam for the target object, it is possible to accurately estimate the characteristics of the target object irradiated with the laser beam (reflecting surface shape, motion, object identification). become.

  Next, a second embodiment will be described.

  FIG. 7 is an explanatory diagram showing the configuration and operation mode of the laser observation system 2 according to the second embodiment.

  The laser observation system 2 includes a plurality of laser devices 10 and a telescope 30. The control unit 20 is connected to a plurality of laser devices 10 via communication lines. Also, observation results and identification target object candidates are shared with other observation systems via a communication line. In the figure, two sets of laser devices 10 and telescopes 30 are shown, but a desired number of combinations may be used.

  The laser apparatus 10 group irradiates a target object with pulsed laser beams having a plurality of wavelengths as a whole system. The system control computer that is the control unit 20 executes object identification from the light receiving waveform shape of the reflected laser light collected by each laser device 10. The system control computer receives the measurement results from the plurality of laser apparatuses 10 and also controls the respective laser ranging functions as necessary. At this time, the object identification is executed by reflecting the observation result obtained by another observation system.

  When a longitudinal single mode laser is used as the laser beam to be used, the wavelength Doppler shift can be detected by heterodyne, and the moving speed and direction of the target can be measured. Heterodyne detection is possible with a single-element photodetector. Heterodyne detection also helps to reduce the required received energy to a minimum.

  When the propagation direction (trajectory) of the target object can be accurately identified, the system control computer controls the LOS angle of each telescope 30 based on the information, and can always keep track of the target object in the optimum direction. .

  As a result, the target object can be tracked favorably as the laser observation system 2.

  FIG. 8A shows a circuit configuration example of a frequency discrimination system that divides into waveform signals of each wavelength when using laser beams of a plurality of wavelengths. This configuration example shows a method of discriminating two laser wavelengths for each wavelength by a dichroic mirror.

  In addition to this, the structure of the optical system circuit may be configured to handle a plurality of wavelengths by a method of shifting the reception timing with time. When discriminating signals by shifting the time, the control unit 20 controls the transmission timing of the pulse laser from each observation point so that a plurality of reflected waves do not overlap depending on the distance from the observation point to the target object. That's fine.

  FIG. 8B is a circuit configuration example of an autonomous tracking method for a target object whose trajectory information is unknown. In autonomous tracking, in order to constantly detect changes in the LOS angle of the target object, a part of the received signal is received by an array sensor such as a CCD (Charge Coupled Device) camera or quadrant detector, and the amount of LOS angle change is calculated. The angle of the telescope 30 is controlled.

  Here, when the array sensor is used, there arises a problem that the amount of received light necessary to obtain the LOS angle change amount increases. As a method for detecting target propagation with less received energy, a method for detecting the speed of a target object by heterodyne is considered.

  By detecting the moving speed of the target object, the LOS angle change amount is calculated and autonomous tracking is performed.

  FIG. 9 shows a configuration example of a laser apparatus 10 for performing heterodyne.

  The optical path of the receiving system in FIG. 9 includes a partial mirror 1 that branches a part of the received light, a mixer that mixes the reference light transmitted from the longitudinal single mode laser oscillator, and the beat waveform of the mixed optical signal. A beat signal detector is provided. The beat signal photoelectrically converted by the beat signal detector is used by the controller 20 to measure the Doppler shift amount of the optical frequency.

  The control unit 20 uses the Doppler shift amount obtained from the beat signal together with the distance measurement data and the LOS angle of the telescope 30 to calculate the relative speed between the observation point and the target object.

  Here, the three-dimensional movement cannot be measured only by the Doppler shift amount at one observation point. For this measure, information at three or more measurement points may be acquired, and the moving direction and moving speed of the target may be derived by calculation using a three-dimensional equation.

  This calculation may be executed by the system control computer (control unit 20) shown in FIG. The system control computer sequentially controls each laser device 10 and the telescope 30 according to the derived trajectory propagation information of the target object, and executes autonomous tracking of the target object.

  As described above, the target identification laser observation system to which the present invention is applied can satisfactorily identify a target object with laser light. In addition, the target identification laser observation system to which the present invention is applied can successfully track the target object.

  The target identification laser observation system has various advantages over the radar observation system. For example, observation is possible day and night. In addition, by using laser observation, the observation range can be set at a high altitude or far away. As a result, the trajectory of the target object existing at a high altitude or far away can be identified with high accuracy.

  Further, the shape recognition of the target object can be identified from one or a plurality of received waveforms. Even when an object cannot be identified, it is possible to estimate size, shape, motion, material, etc., which can be used for object identification.

  Note that the control unit of the laser observation system may be realized using a combination of hardware and software of a computer system. The control unit of the computer system may be realized by developing a laser waveform observation program in the memory and operating hardware such as one or more processors based on the program. At this time, if necessary, this program may realize a desired function in cooperation with a function provided by software such as an operating system, a microprogram, or a driver.

  In addition, this computer system is not necessarily constructed as a single device, and may be constructed by combining a plurality of servers / computers / virtual machines. Further, a part / all of the computer system may be replaced with hardware or firmware (for example, one or a plurality of LSI: Large-Scale Integration, FPGA: Field Programmable Gate Array, a combination of electronic elements). Similarly, only a part of each part may be replaced with hardware or firmware.

  Further, this program may be recorded non-temporarily on a recording medium and distributed. The program recorded on the recording medium is read into the memory via wired, wireless, or the recording medium itself, and operates a processor or the like.

  The present invention has been described by exemplifying embodiments and / or examples. However, the specific configuration of the present invention is not limited to the above-described embodiment, and modifications within a range not departing from the gist of the present invention are included in the present invention. For example, changes such as separation and merging of block configurations and replacement of procedures in the embodiment and / or configuration example described above are free as long as they satisfy the gist of the present invention and the functions described, and the above description limits the present invention. is not.

In addition, a part or all of the above-described embodiments can be described as follows. Note that the following supplementary notes do not limit the present invention.
[Appendix 1]
A telescope aimed at the target object;
A laser device for receiving reflected laser light scattered at a target via the telescope;
A waveform acquisition unit for acquiring a waveform of the reflected laser light;
A determination unit for performing object identification from a light-receiving waveform shape of the reflected laser light;
A target identification laser observation system comprising:

[Appendix 2]
The target identification laser according to the above-mentioned supplementary note, further comprising a distance measuring unit that calculates a distance from the transmission / reception timing of the pulsed laser light generated and irradiated by the laser device and the reflected laser light returned to the target to the target. Observation system.

[Appendix 3]
The target identification laser observation system according to the above supplementary note, further including a database that holds data in which the received light waveform shape of the reflected laser beam and the identification target object candidate are associated with each other, which is used in the determination unit.

[Appendix 4]
The laser device receives reflected laser light scattered by the same target having a plurality of wavelengths,
The waveform acquisition unit acquires the waveforms of the reflected laser beams of the plurality of wavelengths,
The target identifying laser observation system as set forth in the above supplementary note, wherein the determination unit derives an object shape from a light-receiving waveform shape of reflected laser light having a plurality of wavelengths.

[Appendix 5]
The waveform acquisition unit acquires the waveform of the reflected laser light scattered at the same target acquired at a plurality of observation points,
The target identifying laser observation system as set forth in the above supplementary note, wherein the determination unit derives an object shape from received light waveform shapes of a plurality of reflected laser beams.

[Appendix 6]
The laser device, wherein the focused reflected laser light is split into a plurality of laser beams having different wavelengths, and then each reflected laser beam is converted into a waveform signal. Identification laser observation system.

[Appendix 7]
The laser device includes an array sensor that captures reflected laser light reflected by a target,
The target identification laser observation system includes:
An autonomous tracking unit that adjusts the direction of the telescope by deriving a target moving direction and / or moving speed based on the sensor output output at the resolution of the array sensor;
A target identification laser observation system as described in the above supplementary note.

[Appendix 8]
The laser device is
Adopting a vertical single mode laser for the pulsed laser light to irradiate the target,
While branching the reference light from the pulsed laser light to irradiate,
The beat waveform of the optical signal obtained by mixing the collected reflected laser light by the heterodyne method using the reference light is detected,
The target identification laser observation system includes:
Based on the change of the beat waveform, further includes a speed detection unit for deriving a relative speed between the observation point and the target,
A target identification laser observation system as described in the above supplementary note.

[Appendix 9]
At a plurality of observation points, a vertical single mode laser is used as pulse laser light to generate the reference light, and a beat waveform of an optical signal obtained by mixing the collected reflected laser light and the reference light is obtained.
The target identification laser observation system according to the above supplementary note, wherein a current position with respect to the target is derived based on the change in the beat waveform acquired at a plurality of observation points.

[Appendix 10]
The laser apparatus emits a plurality of pulsed laser beams having different wavelengths and / or collects scattered light continuously at a plurality of observation points, and receives light of different wavelengths at different timings obtained at the plurality of observation points. The target identification laser observation system according to the above supplementary note, wherein the object identification is advanced from the waveform shape and the distance from the target object.

[Appendix 11]
A laser emission step of irradiating a target object with laser pulse light;
A laser receiving process for condensing the reflected laser light scattered by the target through a telescope directed at the target object;
A waveform acquisition step of acquiring a waveform of the reflected laser light;
A target identification step of performing object identification from the light-receiving waveform shape of the reflected laser light;
A method of identifying a laser target.

[Appendix 12]
The laser target identification method according to the above supplementary note, further comprising a laser ranging step of calculating a distance from the transmission / reception timing of the laser beam irradiated in the laser emitting step and the reflected laser beam returned upon hitting the target to the target.

[Appendix 13]
The laser target identification method according to the above supplementary note, wherein in the target identification step, a database holding data in which a received light waveform shape of the reflected laser light is associated with an identification target object candidate is referred to.

[Appendix 14]
In the laser light receiving step, reflected laser light scattered by the same target having a plurality of wavelengths is received,
In the waveform acquisition step, each of the reflected laser light waveforms of the plurality of wavelengths is acquired,
In the target identification step, the object shape is derived from the light-receiving waveform shape of the reflected laser light having a plurality of wavelengths.

[Appendix 15]
In the waveform acquisition step, each of the reflected laser light waveforms scattered by the same target acquired at a plurality of observation points, respectively,
In the target identification step, the object shape is derived from the light-receiving waveform shapes of a plurality of reflected laser beams.

[Appendix 16]
In the laser light receiving step, after the reflected arbitrary reflected laser light is split into a plurality of laser lights having different wavelengths, the reflected laser lights are converted into waveform signals, respectively. Laser target identification method.

[Appendix 17]
In the laser receiving step, an array sensor that captures reflected laser light reflected by the target is used.
In the target identifying step, the direction of the telescope is adjusted by deriving a target moving direction and / or moving speed based on the sensor output output at the resolution of the array sensor. The laser target identification method as described.

[Appendix 18]
In the laser emission step, the target is irradiated with the longitudinal single mode pulse laser light, and the reference light is branched from the pulse laser light to be irradiated,
In the laser light receiving step, a beat waveform of an optical signal obtained by mixing the collected reflected laser light by the heterodyne method using the reference light is detected,
In the target identification step, the relative speed between the observation point and the target is derived based on the change in the beat waveform, and the laser target identification method as described in the above supplementary note,

[Appendix 19]
In the laser emission step and the laser light receiving step, light that is obtained by irradiating a pulse laser beam with a longitudinal single mode laser at a plurality of observation points and generating the reference beam, and mixing the reflected laser beam and the reference beam. Get the beat waveform of the signal,
In the target identification step, a current position with respect to a target is derived based on changes in the beat waveform acquired at a plurality of observation points.

[Appendix 20]
In the laser emitting step and the laser receiving step, a laser device emits a plurality of pulsed laser beams having different wavelengths and / or collects scattered light continuously at a plurality of observation points,
The laser identification method according to the above supplementary note, wherein in the target identification step, inference of object identification is advanced from the received light waveform shapes of different wavelengths obtained at a plurality of observation points and different distances from the target object.

  INDUSTRIAL APPLICABILITY The present invention can be used for missions that determine the orbit of debris in outer space and make a database of debris shape and motion state with high accuracy.

  The present invention can also be used for identifying flying objects that fly at high speed in the atmosphere and for identifying relatively small flying objects that fly in the atmosphere.

  In addition, the laser observation system of the present invention can be mounted on a moving body (such as a ship or a flying body) so as to be portable. It is also possible to construct a plurality of laser / radar observation systems to exchange observation data (identified target names, waveform data, distance measurement data, coordinate data, etc.) with each other.

DESCRIPTION OF SYMBOLS 1, 2 Laser observation system 10 Laser apparatus 20 Control part 21 Waveform acquisition part 22 Determination part 30 Telescope

Claims (10)

A telescope aimed at the initially captured target object;
A laser device that receives pulsed laser light that has been scattered and deformed by a target object via the telescope; and
A waveform acquisition unit for acquiring the waveform shape of the deformed pulsed laser beam and the amount of change in the waveform shape;
Based on the received light waveform shape of the deformed pulse laser beam and the amount of change in the waveform shape, at least the surface shape of the target object is estimated without using pattern matching , and object identification that reflects the estimation result is executed. A determination unit to
A target identification laser observation system comprising:
Note that the target object includes an object having no CCR and an object having an unknown shape. The target identification laser observation system according to claim 1, wherein the determination unit continues the object identification process with reference to a distance to the target object .   3. The target identification laser observation according to claim 1, further comprising a database holding data in which the received light waveform shape of the deformed pulsed laser light and the identification target object candidate are associated and used in the determination unit. system. The laser device receives a pulsed laser beam scattered and deformed by the same target object having a plurality of wavelengths,
The waveform acquisition unit acquires the waveform shape of the pulse laser light deformed by the scattering of the plurality of wavelengths and the amount of change in the waveform shape,
The determination unit performs derivation processing of an object shape of a target object based on a received light waveform shape of pulsed laser light deformed by scattering of a plurality of wavelengths and a change amount of the waveform shape. The target identification laser observation system according to claim 1. The waveform acquisition unit acquires the waveform shape for each observation point of the pulse laser light and the amount of change in the waveform shape, which is the same pulse laser light scattered and deformed by the same target object acquired at a plurality of observation points,
The determination unit performs derivation processing of an object shape of a target object based on a received light waveform shape of pulsed laser light deformed by scattering at each of a plurality of observation points and a change amount of the waveform shape. 5. The target identification laser observation system according to any one of 4 above. The laser device divides a focused arbitrary reflected laser beam into a plurality of laser beams having different wavelengths, and then converts each pulsed laser beam that has been scattered and deformed by a target object having a different wavelength into a waveform signal. ,
6. The waveform acquisition unit according to claim 1, wherein the waveform acquisition unit acquires a waveform shape of the deformed pulse laser beam and a change amount of the waveform shape with reference to a waveform signal of at least one of the wavelengths. The target identification laser observation system according to claim 1. The laser device includes an array sensor that captures reflected laser light reflected by a target object,
The target identification laser observation system derives the moving direction and / or moving speed of the target object based on the sensor output output at the resolution of the array sensor together with the program tracking of the captured target object, and the telescope An autonomous tracking unit that adjusts the orientation of the target to the target object;
The target identification laser observation system according to any one of claims 1 to 6. The laser device is
A vertical single mode laser is used for the pulsed laser light to irradiate the target object.
While branching the reference light from the pulsed laser light to irradiate,
The beat waveform of the optical signal obtained by mixing the collected reflected laser light by the heterodyne method using the reference light is detected,
The target identification laser observation system includes:
Based on the change of the beat waveform, further includes a speed detection unit for deriving a relative speed between the observation point and the target object,
The target identification laser observation system according to any one of claims 1 to 6.   A plurality of pulsed laser beams with different wavelengths emitted by the radar device and / or condensing scattered light is continuously performed at a plurality of observation points, and received light waveform shapes of different wavelengths at different timings obtained at the plurality of observation points. The target identification laser observation system according to any one of claims 1 to 8, wherein the object identification process is continuously performed with reference to the distance to the target object. A laser emission step of irradiating the initially captured target object with laser pulse light of one or a plurality of wavelengths;
A laser receiving step for condensing one or a plurality of pulse laser beams of one or a plurality of wavelengths, which are scattered and deformed by the target object via a telescope directed to the initially captured target object, at one or a plurality of observation points;
A waveform acquisition step of acquiring a waveform shape of the pulsed laser light condensed in the laser light receiving step and a change amount of the waveform shape;
Based on the surface shape of the target object estimated based on the received light waveform shape acquired in the waveform acquisition step and the amount of change of the waveform shape without using pattern matching, or based on the surface shape of the target object and past observation results A target identification step for performing object identification reflecting the estimation result ;
A laser target identification method using a lidar system, comprising:
Note that the target object includes an object having no CCR and an object having an unknown shape.

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