阅读说明：本技术 一种基于单像元分布式探测捷联半主动激光导引头及控制方法 (Single-pixel distributed detection-based strapdown semi-active laser seeker and control method ) 是由 张全 王永法 王令玮 张宇鹏 王宇 马微 于 2021-07-29 设计创作，主要内容包括：本发明提供一种基于单像元分布式探测捷联半主动激光导引头及控制方法,用于解决现有技术的导引头存在视场确定后探测距离随之固定的缺陷。基于单像元分布式探测捷联半主动激光导引头包括：一个四象限探测器；四路光学系统；其中每个象限对应一路光学系统。本发明将四个象限分布式单独布置,在满足导引头观测视场的同时,增加了系统焦距,有限克服了作用距离有限的缺陷,并且使导引头系统结构形式灵活多变,适应各种灵活小微弹体结构,保证导引头其他性能不降的同时,增加系统作用距离,有效提高了系统的作战效能。(The invention provides a single-pixel distributed detection-based strapdown semi-active laser seeker and a control method, which are used for solving the defect that the detection distance is fixed after a view field is determined in the seeker in the prior art. Based on single pixel distributed detection strapdown semi-active laser seeker includes: a four-quadrant detector; a four-way optical system; wherein each quadrant corresponds to one optical system. The four quadrants are distributed and arranged independently, so that the observation field of the seeker is met, the system focal length is increased, the defect of limited action distance is overcome, the structural form of the seeker system is flexible and changeable, the seeker system is suitable for various flexible small micro-bullet structures, the action distance of the seeker is increased while other performances of the seeker are not reduced, and the operational efficiency of the seeker system is effectively improved.)

1. A single-pixel-based distributed detection strapdown semi-active laser seeker is characterized by comprising:

a four-quadrant detector; and

a four-way optical system; wherein each quadrant corresponds to one optical system.

2. The single pixel based distributed detection strapdown semi-active laser seeker of claim 1, wherein said four-way optical system has the same operating band.

3. The single-pixel-based distributed detection strapdown semi-active laser seeker of claim 1, wherein two optical systems of said four optical systems located diagonally have the same operating band, and two optical systems located adjacent to each other have different operating bands.

4. The single pixel based distributed detection strapdown semi-active laser seeker of claim 1, wherein said four-way optical system has different operating bands from one another.

5. The single pixel based distributed detection strapdown semi-active laser seeker of claim 3 or 4, wherein a four-way optical system is used to reduce projectile volume and increase focus.

6. The single-pixel-based distributed detection strapdown semi-active laser seeker of claim 3 or 4, wherein the four-way optical system is configured to resist interference light of a predetermined wavelength band.

7. The single pixel based distributed probing strapdown semi-active laser seeker of claim 1, further comprising a controller to calculate azimuth and elevation information from signals received by the probe in the four quadrants.

8. The single-pixel distributed detection strapdown semi-active laser seeker according to claim 7, wherein the controller is configured to extract pulse width and period signals of echo pulses, compare the pulse width and period signals with preset values, consider the echo pulses to be valid pulses if at least two consecutive comparison results both conform to the preset values, and calculate azimuth angle and pitch angle information according to the valid pulses; and if the comparison result does not accord with the preset value, ignoring the current echo pulse signal and waiting for the next echo pulse signal.

9. The control method for the strapdown semi-active laser seeker based on the single-pixel distributed detection of claim 6, comprising:

when the number of the laser pulse signals received by the ith quadrant is larger than a preset value within preset time, ignoring all the laser pulse signals received by the ith quadrant, and changing the emission waveband of the laser; i is 1,2,3 or 4.

Technical Field

The invention relates to the field of semi-active laser seeker, in particular to a single-pixel distributed detection-based strapdown semi-active laser seeker and a control method.

Background

The traditional semi-active laser seeker generally adopts a four-quadrant detector form. The working principle is that a target irradiated by the laser indicator generates diffuse reflection echo, the diffuse reflection echo is focused on a photosensitive surface of the four-quadrant detector through a fairing, a filter lens and a focusing lens group, and the diffuse reflection echo is converted into an electric signal by the four-quadrant detector. And the signal processing control board identifies the code pattern according to the pulse interval, calculates the energy occupied by the light spot in each quadrant on the four-quadrant detector, and calculates the angular deviation of the target relative to the visual axis. The traditional four-quadrant detector laser semi-active seeker design has the defect that the detection distance is fixed after the field of view is determined.

Disclosure of Invention

One purpose of the invention is to solve the defect that the detection distance is fixed after the visual field is determined in the prior art seeker.

According to a first aspect of the present invention, there is provided a single-pixel-based distributed detection strapdown semi-active laser seeker, comprising: a four-quadrant detector; a four-way optical system; wherein each quadrant corresponds to one optical system.

Preferably, the four-way optical systems have the same operating band.

Preferably, the two optical systems of the four optical systems located at diagonal positions have the same optical structure and optical parameters, and the two optical systems located at adjacent positions have different working wavelength bands.

Preferably, the four-way optical systems have mutually different operating bands.

Preferably, a four-way optical system is used to reduce the volume of the projectile and increase the focal length.

Preferably, the four-way optical system is used to resist disturbance light of a preset wavelength band.

Preferably, the seeker further comprises a controller for calculating azimuth and pitch information from signals received by the detector in the four quadrants.

Preferably, the controller is configured to extract a pulse width and a periodic signal of an echo pulse, compare the pulse width and the periodic signal with a preset value, consider the callback pulse as an effective pulse if at least two consecutive comparison results all conform to the preset value, and calculate azimuth angle and pitch angle information according to the effective pulse; and if the comparison result does not accord with the preset value, ignoring the current echo pulse signal and waiting for the next echo pulse signal.

According to a second aspect of the present invention, there is provided a control method for a seeker according to the first aspect of the present invention, including: when the number of the laser pulse signals received by the ith quadrant is larger than a preset value within preset time, ignoring all the laser pulse signals received by the ith quadrant, and changing the emission waveband of the laser; i is 1,2,3 or 4.

The invention has the beneficial effects that:

1. four quadrants are distributed and arranged separately. The method has the advantages that the system focal length is increased while the observation field of the seeker is met, the defect of limited action distance is overcome, the structural form of the seeker system is flexible and changeable, the seeker system is suitable for various flexible small micro-bullet structures, the action distance of the seeker is increased while other performances of the seeker are not reduced, and the combat efficiency of the seeker system is effectively improved.

2. The effective action distance of the seeker is not less than 3km and is increased to 4 km. Namely, the requirement of high resolution of long focal length is ensured while realizing the large visual field.

3. The distributed layout is adopted, so that the system layout is suitable for more small micro-projectiles, and the traditional 'rocket projectiles' with small volume and light weight can be improved from intensive fire into 'precise guidance' weapons.

4. The adoption of a separate layout mode can ensure that a single lens is smaller, realize the possibility of high speed of the missile, realize the common type design with the missile body and reduce the influence of pneumatic heat on window imaging. The discrete and elegant shapes can be hidden at the uniwing cross-section.

Other features of the present invention and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description, serve to explain the principles of the invention.

FIG. 1 is a schematic view of a seeker configuration according to one embodiment of the present invention;

FIG. 2 is a sectional view taken along A-A of FIG. 1;

FIG. 3 is a control flow diagram of one embodiment of the present invention.

Detailed Description

Various exemplary embodiments of the present invention will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions and numerical values set forth in these embodiments do not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses.

Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.

It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.

< first embodiment >

The present embodiment provides a single-pixel-based distributed detection strapdown semi-active laser seeker, as shown in fig. 1 and 2, including: a four-quadrant detector 2; a four-way optical system 1; wherein each quadrant corresponds to one optical system. Each of the four-path optical system 1 has an optical element for adjusting an optical path or reflecting and transmitting light of a specific wavelength band. The four optical systems 1 are respectively arranged in the four aperture structures, and laser passes through the fairing 3 and then respectively passes through the four optical systems to reach the photosensitive surface of the detector 2. The light-sensitive surface of the detector 2 is divided into four quadrants, each quadrant corresponding to one optical system. "corresponding" means that a quadrant can only receive the optical signal transmitted by the optical system opposite to the quadrant. The single pixel means that the detector is a single pixel detector; "distributed" refers to a distributed arrangement of four-way optical systems; "strapdown" means that the seeker is a strapdown seeker; the semi-active laser seeker is characterized in that the seeker automatically captures and tracks a ground fixed/moving target by using laser diffusely reflected by the target, and simultaneously provides a target line-of-sight angle signal relative to a missile axis to a missile autopilot to realize automatic guidance of a missile until the missile automatically hits the target.

A four-quadrant detector in the prior art generally corresponds to the same optical system, and for example, a four-quadrant detector, a corresponding processing circuit, and an optical system are disclosed in the document "target capturing and tracking system of infrared seeker based on four-quadrant detector", and a method for determining target orientation by determining light spot parameters is disclosed in the document "obtaining light spot parameters by using four-quadrant photodetector". The above documents all use an optical system that is larger than the photosensitive surface of the detector to ensure that the spot is present in the appropriate position in each quadrant. Compared with the prior art, the invention has the difference that the invention adopts a four-way optical system, so that 4 light spots corresponding to one target can respectively appear in four quadrants, and the arrangement can reduce the volume of a missile body, increase the focal length and ensure that the missile is easy to realize high speed. The principle is that four distributed optical systems/optical lens groups have a higher utilization ratio than a large optical system, and only a smaller overall volume is required to cover the same detector. On the basis, the focal length can be increased under the condition that the whole volume is not increased, and the upper limit of the focal length and the effective action distance in the prior art is broken through. Meanwhile, due to the fact that the size is reduced, the seeker can easily achieve a streamline shape, and the flying speed of the missile is further increased. Note that, none of the components mentioned in the present embodiment are modified, and for example, the processing circuit, the mechanical structure, and the specific configuration of the optical lens are the same as those in the related art.

Therefore, the single-pixel distributed detection-based strapdown semi-active laser seeker of the embodiment independently arranges four quadrants in a distributed manner. The system has the advantages that the observation field of the seeker is met, the system focal length is increased, the defect of limited action distance is overcome, the structural form of the seeker system is flexible and changeable, and the traditional rocket projectile with small size and light weight can be changed into an accurate guidance weapon from a firepower intensive type. Another significant advantage of the sub-apertures is that by dividing the original single "large" aperture into four "small" apertures, the seeker exposed to the air and mounted to the head will be exposed to the environment, likely to be impacted by sand and insects. The small aperture avoids the interference of tail jet of other rocket guide heads launched from the same launching platform.

Further, in one embodiment, the four-way optical systems have the same operating band. When the optical system is arranged in this way, the working principle is similar to that of the prior art, and the optical system is equivalent to the distributed arrangement of the original single optical system. The arrangement overcomes the defects that the working distance has obvious upper limit, the focal length is short, and the appearance structure is not easy to realize high speed and miniaturization in the prior art. The working waveband refers to a wavelength range which can be received by the optical system, and can represent the reflection and transmission characteristics of the optical system.

In another embodiment, the four-way optical system has different operating bands and can be used to reject interference light in a predetermined band. The literature, "influence of laser seeker detection performance on high repetition frequency interference laser", discloses a study on signal interference on a seeker by using high repetition frequency interference equipment. An example of the principle is: in the prior art, a certain seeker is used for receiving laser in a certain waveband, and another interference device in a detection range transmits high-repetition-frequency interference laser in the same waveband, and at the moment, a photosensitive surface of a detector receives a large number of laser signals in a short time, so that a controller needs to process a large number of pulse signals in a short time, the upper limit of the processing capacity is exceeded, and the seeker cannot normally track and lock a target. In order to prevent the seeker from being affected by the interference of the laser, in this embodiment, the four-way optical system may be set to different wave bands (specifically, the reflection and transmission characteristics of the lens to light in a specific wave band may be adjusted by plating a material and a film on the surface of the lens), and when one wave band is interfered, the setting of the detector is changed, so that the controller does not receive and process signals in the quadrant, thereby avoiding the influence of interference signals.

The four optical systems can also be arranged in such a way that two optical systems at diagonal positions have the same working wave band, and two optical systems at adjacent positions have different working wave bands. The advantage of setting up like this can ensure that this wave band has great detection range, avoids can not receiving laser signal because echo signal angle problem. If the two optical systems are arranged on one side, the detection ranges of the two optical systems with the same wave band are overlapped, and the detection range is not favorably expanded.

One specific example is provided below: the missile and the laser are carried on the aircraft, the laser periodically emits laser with a preset wave band to a target, the laser is received by a seeker on the missile body after being reflected by the target, and a controller in the seeker can calculate azimuth angle and pitch angle information according to signals received by a detector in four quadrants, so that the normal working process is realized. And another interference device near the target at a certain moment emits laser with the same wave band and has a high repetition frequency characteristic, so that a detector in the seeker receives a large number of pulse signals in a short time, the controller cannot judge which pulse signal is reflected by the target, if the controller is set to process each signal, the controller needs to process a large number of data in a short time, and the missile is very likely to fail to complete the identification and tracking of the target. However, if the seeker provided by the embodiment of the invention is adopted, because the four-way optical system has different transmission characteristics and reflection characteristics, only one quadrant can be interfered at most, and when the controller detects that a large amount of interference light appears in the quadrant, all signals of the quadrant can be ignored. And the other three optical systems only allow light of a specific wave band to pass through and light of other wave bands cannot reach the photosensitive surface of the detector due to the fact that specific materials and antireflection films or antireflection films are plated on the other three optical systems, and therefore interference can be avoided only by switching the wave bands of the laser. For example, the laser can emit laser light of 4 wave bands, which respectively correspond to the four optical systems, when the interference device adopts the laser light of the first wave band for interference, the controller ignores the quadrant corresponding to the interference device, and changes the laser to emit the laser light of the second wave band, and receives and processes the signal through another light path. The influence of disturbing light on the seeker is avoided.

The controller can also be used for extracting pulse width and periodic signals of the echo pulse, comparing the pulse width and periodic signals with a preset value, if the comparison results of at least two continuous times are consistent with the preset value, considering the echo pulse as an effective pulse, and calculating azimuth angle and pitch angle information according to the effective pulse; and if the comparison result does not accord with the preset value, ignoring the current echo pulse signal and waiting for the next echo pulse signal. That is, there is a specific pulse width and period of the laser emitted by the laser, and the laser signal received by the seeker may not be all from the target, or may be from the atmosphere reflection signal or other interference source, so that the controller will determine the pulse width and period of the signal when detecting the pulse signal, and if several consecutive signals are the same as the preset value, the signal is considered as the echo signal from the target, and then the azimuth angle and the pitch angle are calculated based on the signal. As shown in fig. 3, it can be seen that the seeker starts to search for a target first, and determines whether the pulse width and the period of the pulse signal received by the seeker are the same as the set values of the synchronization signal according to the pulse width and the period information set by the synchronization signal, and if not, searches for the next target again; if yes, starting counting, and judging whether the next signal also accords with a set value; until three continuous signals are all matched, the pulse signal is considered to come from the target, and then the azimuth information of the target is calculated.

In the example shown in fig. 3, the four-way individual DSP flash memory may store the fixed frequency laser code and the pseudorandom laser code types in advance, and embed the common parameter settings therein, and when there is binding information, perform code pattern recognition using the binding information. When the binding information does not exist, searching the code type library, performing pulse period matching, calculating at least two pulses in one period, wherein the time is about 50ms (depending on the code pattern period), and needing to confirm at least three periods of the code pattern.

Fig. 3 shows an example in which four individual channels utilize uniform code recognition software, in the same manner as conventional four quadrant processing. The four optical channels that are respectively acted on are respectively considered as four quadrants of the four-term detector. The synchronous signals generated by the summing comparison shaping circuit are processed, signals such as pulse width, period and the like of echo pulses are extracted and then compared with a known set value, if the set requirement is met, the signals are regarded as valid signals, and if the signals do not meet the set requirement, the signals are regarded as invalid signals. In order to improve the detection accuracy, three effective pulses are detected continuously and are considered as a target. And if an invalid pulse is detected, restarting searching, and after the target is determined to be detected, starting resolving the angle signal of the target to finally obtain azimuth angle information and pitch angle information.

< second embodiment >

The embodiment provides a control method of a seeker based on the first embodiment, which comprises the following steps: when the number of the laser pulse signals received by the ith quadrant is larger than a preset value within preset time, ignoring all the laser pulse signals received by the ith quadrant, and changing the emission waveband of the laser; i is 1,2,3 or 4.

The process of one embodiment is: the laser is set to emit laser in a first wave band, and the laser in the first wave band can reach a first quadrant of the detector through the first optical system; the interference unit also emits laser light of a first wave band; when the controller identifies that the number of pulses received by the first quadrant is larger than a preset value in unit time, the controller does not process pulse signals received by the first quadrant any more, then the laser is changed to emit laser of a second wave band, and the laser of the second wave band can reach the second quadrant of the detector through the second optical system. The wave band of the interference laser is the same as the first wave band, so that the interference laser cannot reach the second quadrant of the detector through the second optical system, the purpose of interference resistance is achieved, the laser received by the second quadrant comes from the laser carried on the aircraft, and the seeker can normally track and identify the target.

< third embodiment >

The guidance head provided by the embodiment is used for improving firepower intensive weapons into accurately guided weapons. Further, it is used for improving rocket projectile into precision guided weapon. Because the body volume of firepower intensive weapons such as rocket projectiles is smaller, a larger one-way optical system in the prior art cannot be arranged in the guidance head, and the four-way optical system is used for corresponding to four quadrants, so that the overall volume is reduced, and the firepower intensive weapons such as rocket projectiles can also use a high-precision guidance system. The structure of the present embodiment is the same as that of the first embodiment, and the control method is the same as that of the second embodiment.

Although some specific embodiments of the present invention have been described in detail by way of examples, it should be understood by those skilled in the art that the above examples are for illustrative purposes only and are not intended to limit the scope of the present invention. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the invention. The scope of the invention is defined by the appended claims.