Laser alignment and calibration apparatus for remote laser encrypted communication system, and application method of laser alignment and calibration apparatus

Abstract

The present invention relates to the technical field of laser communications. Disclosed are a laser alignment and calibration apparatus for a remote laser encrypted communication system, and an application method of the laser alignment and calibration apparatus, which apparatus and application method are used for solving the problem of laser alignment and calibration in a remote laser encrypted communication system. A laser detector and a laser transmitter are integrated at a communication transmitting end, and a laser reflection baffle and a photoelectric XOR logic gate are arranged in parallel at a communication receiving end, thereby realizing self-feedback adjustment of the laser intensity. With the aid of an omnidirectional rotating platform and a three-axis moving platform, automatic laser alignment is realized by means of signal output feedback of the photoelectric XOR logic gate. Throughout the process, it is not necessary to use additional radio communication to perform interactive feedback, such that the security and reliability of remote laser encrypted communication are further improved, the complexity of the communication system is reduced, and the communication stability is improved, thereby achieving a wide application prospect in both the military field and the civil field.

Description

Laser alignment and correction device for long-distance laser encryption communication system and application method Technical field:

[0001] The present invention relates to the field of laser communication technology, and in particular to a laser alignment and correction device for a long-distance laser encryption communication system and an application method thereof. Background technology:

[0002] Long-range laser encrypted communication technology uses directional and concealed lasers as a carrier to transmit encrypted information, and uses optoelectronic XOR logic gates as signal conversion devices to automatically decrypt the laser signals. This technology enables secure, stable, and high-speed encrypted communication, and has therefore attracted widespread attention. Laser alignment, a crucial component of long-range laser encrypted communication, is a prerequisite for ensuring stable, reliable, and accurate communication. This requires the simultaneous alignment of multiple laser beams and the appropriate output power of the laser transmitter to meet the proper operation of the optoelectronic XOR logic gates. Currently, laser alignment devices and methods in long-range laser communication systems often rely on traditional radio communication technology for real-time feedback and adjustment. This laser alignment method is not only complex and cumbersome, but also, because the electromagnetic waves used in traditional radio communication technology propagate freely in space, they are easily eavesdropped and hijacked, compromising security. Therefore, the development of a laser alignment and correction device and application method that does not require additional radio communication for interactive feedback would help further improve the security and reliability of long-range laser encrypted communication.

[0003] Summary of the invention:

[0004] The present invention provides a laser alignment and correction device for a long-distance laser encryption communication system and an application method thereof, which solve the difficult problems of laser alignment and correction in the long-distance laser encryption communication system in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solutions:

[0006] In a first aspect, the present invention provides a laser alignment and correction device for a long-distance laser encryption communication system, comprising: a laser transmitter A, a laser transmitter B, a laser beam expander A, a laser beam expander B, a photoelectric XOR logic gate, a laser reflection baffle, a laser detector A, a laser detector B, a universal rotating platform, and a three-axis mobile platform.

[0007] The laser transmitter A and the laser transmitter B are used to send ciphertext and key of laser encrypted communication respectively;

[0008] The laser beam expander A and the laser beam expander B are respectively installed at the front ends of the laser emitter A and the laser emitter B, and are used to continuously adjust the size of the laser spot;

[0009] The photoelectric XOR logic gate is used to receive the laser signal emitted by the laser transmitter and realize automatic decryption output;

[0010] The laser reflection baffle is arranged in parallel at the front end of the photoelectric XOR logic gate to achieve mirror reflection of the laser;

[0011] The laser detector A and the laser detector B are respectively installed on the laser emitter A and the laser emitter B, and are used to detect the intensity and frequency of the laser signal reflected back by the laser reflection baffle.

[0012] As described above, the laser alignment and correction device for a long-distance laser encryption communication system, further, the laser reflection baffle is set to two states: closed and open. In the closed state, the laser is irradiated on the reflection baffle to produce mirror reflection, and in the open state, the laser will irradiate the light response area of ​​the photoelectric XOR logic gate.

[0013] As described above, the laser alignment and correction device for a long-distance laser encryption communication system, further, the laser emitter can adjust the light intensity to a light intensity that satisfies the normal operation of the photoelectric XOR logic gate through a preset algorithm based on the light intensity of the reflected laser detected by the laser detector.

[0014] The laser alignment and correction device for a long-distance laser encryption communication system as described above, further, the universal rotating platform is used to carry the photoelectric XOR logic gate and the laser reflection baffle, and can achieve fine adjustment of any angle.

[0015] The laser alignment and correction device for a long-distance laser encryption communication system as described above, further, the three-axis mobile platform is used to carry the photoelectric XOR logic gate, the laser reflection baffle and the universal rotating platform, which can achieve precise displacement in three-dimensional space.

[0016] In a second aspect, the present invention provides an application method of the laser alignment and correction device for a long-range laser encryption communication system as described above, comprising the following steps:

[0017] At the communication transmitting end, when laser communication is not in progress, laser transmitter A and laser transmitter B are in a closed state;

[0018] At the communication receiving end, when laser communication is not in progress, the photoelectric XOR logic gate rotates at a constant speed along the vertical axis, keeping the laser reflection baffle open and in a signal search state ready at any time;

[0019] At the communication transmitting end, after receiving the command to conduct laser communication with the communication receiving end, the laser transmitter A is started, the laser transmitting power is kept constant, and with the assistance of the positioning system, the laser of the laser transmitter A is emitted in the direction of the photoelectric exclusive OR logic gate of the communication receiving end. According to the distance between the communication transmitting end and the communication receiving end, the laser beam expander A is adjusted so that the laser spot irradiated on the communication receiving end is larger than the accuracy of the positioning system, ensuring that the laser spot can cover the photoelectric exclusive OR logic gate;

[0020] At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser transmitter A, the photoelectric XOR logic gate shows a sudden increase in the light response signal, which means that laser transmitter A is trying to align with it. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. Then, it keeps its direction unchanged and moves to the position with the strongest light response signal. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. Then, it records the position and direction. At this time, the photoelectric XOR logic gate is located at the center of the laser spot, and the laser is incident along the normal direction of the photoelectric XOR logic gate. Then, the laser reflection baffle is repeatedly opened and closed at a frequency f, and the laser is reflected back to the laser detector A at the communication transmitting end at a frequency f.

[0021] The application method as described above, further,

[0022] At the communication transmitting end, after laser detector A receives the reflected signal with a frequency of f, it adjusts laser beam expander A to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector A decreases, it means that the light spot has deviated from the optical response area of ​​the photoelectric XOR logic gate. The reduction of the light spot diameter stops, the emission angle of laser emitter A is maintained unchanged, the position of laser emitter A is fine-tuned, and after re-tracking to the position where laser detector A detects the strongest reflected laser, the light spot diameter continues to be reduced until the light spot size can just cover the optical response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector A, the power of laser emitter A is adjusted through an algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements of its normal operation. Then, laser emitter A is turned off, and a message is sent to laser emitter B that the alignment of laser emitter A is completed.

[0023] At the communication receiving end, after the photoelectric XOR logic gate detects a sudden drop in the light response signal, it confirms that the alignment of laser reflector A is complete, then opens the laser reflection baffle, keeps the position and direction of the photoelectric XOR logic gate unchanged, and waits for alignment with laser emitter B;

[0024] At the communication transmitting end, after receiving the message from laser transmitter A that the alignment is complete, laser transmitter B starts laser transmitter B and keeps the laser transmitting power unchanged. With the assistance of the positioning system, the laser of laser transmitter B is emitted in the direction of the photoelectric XOR logic gate at the communication receiving end. According to the distance between the communication transmitting end and the communication receiving end, laser beam expander B is adjusted so that the laser spot irradiated on the communication receiving end is larger than the positioning system accuracy, ensuring that the laser spot can cover the photoelectric XOR logic gate.

[0025] At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser emitter B, the photoelectric XOR logic gate shows an obvious surge in light response signal, which means that laser emitter B is trying to align with it. Then, the direction remains unchanged and moves along the normal direction of the photoelectric XOR logic gate, that is, the laser emission direction of laser emitter A, to the position where the light response signal is the strongest. Then, the position remains unchanged and rotates to the direction where the light response signal is the strongest. The position and direction are then recorded. At this time, the laser is incident along the normal direction of the photoelectric XOR logic gate, and then the laser reflection baffle is repeatedly opened and closed at a frequency f, reflecting the laser back to the laser detector B at the communication transmitting end at a frequency f.

[0026] The application method as described above, further,

[0027] At the communication transmitting end, after laser detector B receives the reflected signal with a frequency of f, it adjusts laser beam expander B to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector B decreases, it means that the light spot has deviated from the optical response area of ​​the photoelectric XOR logic gate. The reduction of the light spot diameter stops, the emission angle of laser emitter B is maintained unchanged, the position of laser emitter B is fine-tuned, and after re-tracking to the position where laser detector B detects the strongest reflected laser, the light spot diameter continues to be reduced until the light spot size can just cover the optical response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector B, the power of laser emitter B is adjusted through the algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements of its normal operation. Then, laser emitter B is turned off, and a message is sent to laser emitter A that the alignment of laser emitter B is completed.

[0028] At the communication transmitting end, after receiving the message from laser transmitter B that the alignment is complete, laser transmitter A starts laser transmitter A and keeps the laser transmitting power unchanged;

[0029] At the communication receiving end, the photoelectric XOR logic gate detects a sudden drop in the light response signal, confirming that the alignment of laser emitter B is complete. After that, the position remains unchanged. Through algorithm calculation, the normal angle of the photoelectric XOR logic gate is adjusted to be exactly at the center position of the two laser beams of laser A and laser B, ensuring that the incident angles of the two laser beams are consistent. At this time, the laser emitted by laser emitter A is reflected by the laser reflection baffle at a frequency f to laser detector B. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value when the photoelectric XOR logic gate input is (1, 0);

[0030] At the communication transmitting end, laser detector B receives the reflected laser of frequency f, confirms that all alignment and calibration are complete, and then starts laser transmitter B, notifying laser transmitter A through the reflected signal that all alignment and calibration are complete.

[0031] At the communication transmitter, laser detector A receives the reflected laser light of frequency f, confirming that all alignment and corrections have been completed.

[0032] At the communication receiving end, the photoelectric XOR logic gate changes from being illuminated by laser emitter A alone to being illuminated by laser emitter A and laser emitter B together. The light response signal suddenly drops, confirming that both laser emitter A and laser emitter B are aware that all alignment and calibration have been completed. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value when the input of the photoelectric XOR logic gate is (1, 1). Then, the threshold of the photoelectric XOR logic gate is set to be greater than the output signal value when the input is (1, 1) and less than the output signal value when the input is (1, 0). Then, the laser reflection baffle is opened, and the transmission of remote laser encrypted information is waited for. At this time, the reflection of the laser emitted by the communication transmitting end will be greatly weakened, and the frequency becomes 0.

[0033] At the communication transmitting end, the reflected laser received by laser detector A and laser detector B suddenly drops and the frequency drops to 0, confirming that the photoelectric XOR logic gate is working normally and starts sending remote laser encrypted information.

[0034] In the application method described above, further, the switching frequency f of the laser reflection baffle is jointly determined by the response speeds of the photoelectric XOR logic gate, laser detector A and laser detector B, satisfying that 1 / f is greater than the response speed.

[0035] Compared with the prior art, the present invention has the following beneficial effects:

[0036] This invention enables automatic laser alignment and correction without the need for additional radio communication for interactive feedback, further enhancing the security and reliability of long-range laser encrypted communications. Furthermore, this invention can further enhance the security of laser communications, reduce the complexity of communication systems, and improve communication stability, promising broad application prospects in both military and civilian fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0038] FIG1 is a schematic diagram of a laser alignment and correction device for a long-range laser encryption communication system according to an embodiment of the present invention;

[0039] FIG2 is an input-output characteristic curve of a photoelectric XOR logic gate in an embodiment of the present invention;

[0040] FIG3 is a schematic diagram of an application method of a laser alignment and correction device for a long-range laser encryption communication system according to an embodiment of the present invention;

[0041] Explanation of the accompanying symbols: 1. Laser emitter A; 2. Laser emitter B; 3. Laser beam expander A; 4. Laser beam expander B; 5. Photoelectric XOR logic gate; 6. Laser detector A; 7. Laser detector B; 8. Laser reflection baffle; 9. Universal rotating platform; 10. Three-axis moving platform. Specific implementation method:

[0042] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0043] Example:

[0044] It should be noted that the terms "first", "second", etc. in the description and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the numbers used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof in the embodiments of the present invention are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0045] In the description of the present invention, "plurality" means at least two, such as two or three, unless otherwise specifically defined. Furthermore, unless otherwise specified or defined, the terms "mounted," "connected," and "connected" should be understood broadly, meaning, for example, fixed, removable, or integral; mechanical or electrical; direct or indirect through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention.

[0046] In response to the deficiencies in the prior art, the present invention provides a laser alignment and correction device and method for a long-distance laser encrypted communication system, which can achieve automatic laser alignment and correction without the need for additional radio communication for interactive feedback, further improving the security and reliability of long-distance laser encrypted communication.

[0047] This embodiment provides a laser alignment and correction device for a long-distance laser encryption communication system, as shown in Figure 1, which includes: a laser transmitter A1 and a laser transmitter B2 arranged at the communication transmitting end, a laser beam expander A3 and a laser beam expander B4 respectively installed at the front end of the laser transmitter A1 and the laser transmitter B2, and a laser detector A6 and a laser detector B7 respectively integrated on the laser transmitter A1 and the laser transmitter B2, as well as a photoelectric XOR logic gate 5 arranged at the communication receiving end, a laser reflection baffle 8 arranged at the front end of the photoelectric XOR logic gate 5, a universal rotating platform 9 for carrying the photoelectric XOR logic gate 5, and a three-axis mobile platform 10 for carrying the universal rotating platform 9.

[0048] Referring to the characteristic parameters of the photoelectric XOR logic gate in the patent "A method for preparing bismuth oxide thin films and reconfigurable photoelectric logic gate", its input-output characteristics are shown in Figure 2. In Figure 2, the horizontal axis represents the light intensity of laser emitter A or B irradiating the photoelectric XOR logic gate. The constraint condition is that the light intensity irradiated by laser emitter A and laser emitter B on the photoelectric XOR logic gate is the same, and the vertical axis represents the open circuit potential output by the photoelectric XOR logic gate. When the light intensity irradiated by laser emitter A or laser emitter B on the photoelectric XOR logic gate is greater than 1.05mW / cm 2 When the input is (0,0) and (1,1), the output is 0, and when the input is (1,0) and (0,1), the output is 1.

[0049] FIG3 is a schematic diagram of an application method of the laser alignment and correction device for a long-distance laser encryption communication system provided by this embodiment, which specifically includes the following steps:

[0050] At the communication transmitting end, when laser communication is not in progress, laser transmitter A and laser transmitter B are in a closed state;

[0051] At the communication receiving end, when laser communication is not in progress, the photoelectric XOR logic gate rotates uniformly along the vertical axis at a speed of 1 to 10 seconds per revolution, keeping the laser reflection baffle open and in a signal search state ready at any time;

[0052] At the communication transmitting end, after receiving the command to conduct laser communication with the communication receiving end, start laser transmitter A and keep the laser transmission power unchanged. With the assistance of the positioning system, the laser of laser transmitter A is emitted in the direction of the photoelectric exclusive OR logic gate of the communication receiving end. According to the distance between the communication transmitting end and the communication receiving end, adjust the laser beam expander A so that the laser spot irradiated on the communication receiving end is larger than the positioning system accuracy to ensure that the laser spot can cover the photoelectric exclusive OR logic gate. Taking the 2.34-meter accuracy of the Beidou satellite positioning system as an example, the laser spot diameter needs to be adjusted to 2.5 meters.

[0053] At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser transmitter A, the photoelectric XOR logic gate has a sudden increase in the light response signal, which means that laser transmitter A is trying to align with it. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. Then, it keeps its direction unchanged and moves to the position with the strongest light response signal. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. The position and azimuth at this time are recorded as α A and the pitch angle is β A At this time, the photoelectric XOR logic gate is located at the center of the laser spot, and the laser is incident along the normal direction of the photoelectric XOR logic gate. Then, the laser reflection baffle is repeatedly opened and closed at a frequency of 10 times / second, and the laser is reflected back to the laser detector A at the communication transmitting end at a frequency of 10 times / second.

[0054] At the communication transmitting end, after laser detector A receives the reflected signal with a frequency of 10 times / second, it adjusts laser beam expander A to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector A decreases, it means that the light spot has deviated from the light response area of ​​the photoelectric XOR logic gate. Stop reducing the diameter of the light spot, maintain the emission angle of laser emitter A unchanged, fine-tune the position of laser emitter A, and re-track to the position where laser detector A detects the strongest reflected laser. Continue to reduce the diameter of the light spot until the size of the light spot can just cover the light response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector A, the power of laser emitter A is adjusted through the algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements of its normal operation. Specifically, the laser light intensity emitted by laser emitter A is recorded as I 0A The intensity of the laser irradiating the photoelectric XOR logic gate is recorded as I1A The intensity of the reflected laser light received by laser detector A is recorded as I 2A , the laser reflectivity of the laser reflection baffle is recorded as R, and the laser attenuation obeys the Lambert-Beer law, so it can be known that: I 1A =I 0A e -(α+s)L (1) I 2A =RI 1Ae -(α+s)L (2)

[0055] Where α and s are the light absorption coefficient and scattering coefficient respectively. Substituting formula (1) into formula (2), we can get: 2A =RI 0A e -2(α+s)L (3)

[0056] Among them I 0A and I 2A All can be measured directly at the communication transmitter, so it can be calculated:

[0057] Therefore, formula (1) can be expressed as:

[0058] Therefore, it is only necessary to obtain I 0A and I 2A , the intensity of the laser received by the photoelectric XOR logic gate can be calculated 1A According to the input-output characteristics of the photoelectric XOR logic gate shown in Figure 2, the intensity of the laser received by the photoelectric XOR logic gate I 1A Adjust to greater than 1.05mW / cm 2 It can meet the needs of its normal operation, comprehensively consider the energy consumption of laser transmitter A and the sensitivity of photoelectric XOR logic gate, and adjust the power of laser transmitter A to adjust the intensity of laser received by photoelectric XOR logic gate I 1A Adjust to 5mW / cm 2 , then turn off laser transmitter A, and then send a message to laser transmitter B that the alignment of laser transmitter A is completed;

[0059] At the communication receiving end, after the photoelectric XOR logic gate detects a sudden drop in the light response signal, it confirms that the alignment of laser reflector A is complete, then opens the laser reflection baffle, keeps the position and direction of the photoelectric XOR logic gate unchanged, and waits for alignment with laser emitter B;

[0060] At the communication transmitting end, after receiving the message from laser transmitter A that alignment is complete, laser transmitter B starts laser transmitter B and maintains the laser transmission power unchanged. With the assistance of the positioning system, laser transmitter B emits the laser in the direction of the optoelectronic XOR logic gate at the communication receiving end. Based on the distance between the communication transmitting end and the communication receiving end, laser beam expander B is adjusted so that the diameter of the laser spot irradiated on the communication receiving end is 2.5 meters, ensuring that the laser spot can cover the optoelectronic XOR logic gate.

[0061] At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser emitter B, the photoelectric XOR logic gate shows an obvious light response signal surge, which means that laser emitter B is trying to align with it. Then, the direction remains unchanged and moves along the normal direction of the photoelectric XOR logic gate, that is, the laser emission direction of laser emitter A, to the position where the light response signal is the strongest. Then, the position remains unchanged and rotates to the direction with the strongest light response signal. The position and azimuth at this time are recorded as α B and the pitch angle is β B At this time, the laser is incident along the normal direction of the photoelectric XOR logic gate, and then the laser reflection baffle is repeatedly opened and closed at a frequency of 10 times / second, reflecting the laser back to the laser detector B at the communication transmitting end at a frequency of 10 times / second.

[0062] At the communication transmitting end, after laser detector B receives the reflected signal with a frequency of 10 times / second, it adjusts laser beam expander B to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector B decreases, it means that the light spot has deviated from the optical response area of ​​the photoelectric XOR logic gate. Stop reducing the diameter of the light spot, maintain the emission angle of laser emitter B unchanged, fine-tune the position of laser emitter B, and re-track to the position where laser detector B detects the strongest reflected laser. Continue to reduce the diameter of the light spot until the size of the light spot can just cover the optical response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector B, the power of laser emitter B is adjusted through the algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements of its normal operation. Specifically, the laser light intensity emitted by laser emitter B is recorded as I 0B The intensity of the laser irradiating the photoelectric XOR logic gate is recorded as I 1B , the intensity of the reflected laser received by laser detector B is recorded as I 2B According to formula (5), we can know that:

[0063] By adjusting the power of laser transmitter B, the intensity of the laser received by the photoelectric XOR logic gate is 1B Adjust to 5mW / cm 2 , then turn off laser transmitter B, and then send a message to laser transmitter A that the alignment of laser transmitter B is completed;

[0064] At the communication transmitting end, after receiving the message from laser transmitter B that the alignment is complete, laser transmitter A starts laser transmitter A and keeps the laser transmitting power unchanged;

[0065] At the communication receiving end, the photoelectric XOR logic gate detects a sudden drop in the light response signal, confirming that the alignment of laser transmitter B is complete. After that, the position remains unchanged. Through algorithm calculation, the azimuth angle of the photoelectric XOR logic gate is adjusted to α and the pitch angle to β. The specific calculation is performed by the following formula:

[0066] At this time, the normal angle of the photoelectric XOR logic gate is exactly at the center position of the two laser beams of laser A and laser B, ensuring that the incident angles of the two laser beams are consistent. The laser emitted by laser emitter A is reflected by the laser reflection baffle at a frequency of 10 times / second to laser detector B. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value V1 = 535mV when the input of the photoelectric XOR logic gate is (1, 0);

[0067] At the communication transmitting end, laser detector B receives the reflected laser at a frequency of 10 times / second, confirming that all alignment and calibration have been completed, and then starts laser transmitter B, which notifies laser transmitter A through the reflected signal that all alignment and calibration have been completed;

[0068] At the communication transmitting end, laser detector A receives the reflected laser at a frequency of 10 times / second, confirming that all alignment and correction have been completed;

[0069] At the communication receiving end, the photoelectric XOR logic gate is changed from being illuminated by laser emitter A alone to being illuminated by laser emitter A and laser emitter B together. The light response signal suddenly drops, confirming that both laser emitter A and laser emitter B are aware that all alignment and calibration are complete. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value V2 = 551mV when the photoelectric XOR logic gate input is (1, 1). The threshold of the photoelectric XOR logic gate is then set to be greater than V2 and less than V1. In this embodiment, the threshold of the photoelectric XOR logic gate is set to 543mV. The laser reflection baffle is then opened, and the transmission of remote laser encrypted information is waited for. At this time, the reflection of the laser emitted by the communication transmitting end will be greatly weakened, and the frequency becomes 0.

[0070] At the communication transmitting end, the reflected laser received by laser detector A and laser detector B suddenly drops and the frequency drops to 0, confirming that the photoelectric XOR logic gate is working normally and starts sending remote laser encrypted information.

[0071] It should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like to indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation, and therefore should not be understood as limiting the present invention.

[0072] In the present invention, unless otherwise expressly specified or limited, when a first feature is "above" or "below" a second feature, it may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediary. Furthermore, when a first feature is "above," "above," or "above" a second feature, it may mean that the first feature is directly above or diagonally above the second feature, or simply means that the first feature is at a higher level than the second feature. When a first feature is "below," "below," or "below" a second feature, it may mean that the first feature is directly below or diagonally below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0073] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification and features of different embodiments or examples without contradiction.

[0074] The above embodiments are intended only to illustrate the technical concepts and features of the present invention. Their purpose is to enable those skilled in the art to understand the contents of the present invention and implement them accordingly. They are not intended to limit the scope of protection of the present invention. Any equivalent changes or modifications made based on the essence of the present invention are intended to be covered by the scope of protection of the present invention.

Claims

1. A laser alignment and correction device for a long-range laser encryption communication system, characterized in that: include: Laser transmitter A, laser transmitter B, laser beam expander A, laser beam expander B, photoelectric XOR logic gate, laser reflection baffle, laser detector A, laser detector B, universal rotating platform and three-axis mobile platform, The laser transmitter A and the laser transmitter B are used to send ciphertext and key of laser encrypted communication respectively; The laser beam expander A and the laser beam expander B are respectively installed at the front ends of the laser emitter A and the laser emitter B, and are used to continuously adjust the size of the laser spot; The photoelectric XOR logic gate is used to receive the laser signal emitted by the laser transmitter and realize automatic decryption output; The laser reflection baffle is arranged in parallel at the front end of the photoelectric XOR logic gate to achieve mirror reflection of the laser; The laser detector A and the laser detector B are respectively installed on the laser emitter A and the laser emitter B, and are used to detect the intensity and frequency of the laser signal reflected back by the laser reflection baffle.

2. The laser alignment and correction device for a long-range laser encryption communication system according to claim 1, characterized in that: The laser reflection baffle is set to two states: closed and open. In the closed state, the laser is irradiated on the reflection baffle to generate mirror reflection. In the open state, the laser will irradiate the light response area of ​​the photoelectric XOR logic gate.

3. The laser alignment and correction device for a long-range laser encryption communication system according to claim 1, characterized in that: The laser emitter can adjust the light intensity to a light intensity that satisfies the normal operation of the photoelectric XOR logic gate according to the light intensity of the reflected laser detected by the laser detector through a preset algorithm.

4. The laser alignment and correction device for a long-range laser encryption communication system according to claim 1, characterized in that: The universal rotating platform is used to carry the photoelectric XOR logic gate and the laser reflection baffle, and can achieve fine adjustment at any angle.

5. The laser alignment and correction device for a long-range laser encryption communication system according to claim 1, characterized in that: The three-axis mobile platform is used to carry the photoelectric XOR logic gate, the laser reflection baffle and the universal rotating platform, and can achieve precise displacement in three-dimensional space.

6. A method for applying the laser alignment and correction device for a long-distance laser encryption communication system according to any one of claims 1 to 5, characterized in that: The following steps are involved: At the communication transmitting end, when laser communication is not in progress, laser transmitter A and laser transmitter B are in a closed state; At the communication receiving end, when laser communication is not in progress, the photoelectric XOR logic gate rotates at a constant speed along the vertical axis, keeping the laser reflection baffle open and in a signal search state ready at any time; At the communication transmitting end, after receiving the command to communicate with the communication receiving end, the laser transmitter A is started, the laser transmitting power is kept constant, and with the assistance of the positioning system, the laser of the laser transmitter A is emitted in the direction of the photoelectric exclusive OR logic gate of the communication receiving end. According to the distance between the communication transmitting end and the communication receiving end, the laser beam expander A is adjusted so that the laser spot irradiated on the communication receiving end is larger than the positioning system precision. Degree, to ensure that the laser spot can cover the photoelectric XOR logic gate; At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser transmitter A, the photoelectric XOR logic gate shows a sudden increase in the light response signal, which means that laser transmitter A is trying to align with it. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. Then, it keeps its direction unchanged and moves to the position with the strongest light response signal. Then, it keeps its position unchanged and rotates to the direction with the strongest light response signal. Then, it records the position and direction. At this time, the photoelectric XOR logic gate is located at the center of the laser spot, and the laser is incident along the normal direction of the photoelectric XOR logic gate. Then, the laser reflection baffle is repeatedly opened and closed at a frequency f, and the laser is reflected back to the laser detector A at the communication transmitting end at a frequency f.

7. The application method according to claim 6, characterized in that: At the communication transmitting end, after laser detector A receives the reflected signal with a frequency of f, it adjusts laser beam expander A to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector A decreases, it means that the light spot has deviated from the optical response area of ​​the photoelectric XOR logic gate. The reduction of the light spot diameter stops, the emission angle of laser emitter A is maintained unchanged, the position of laser emitter A is fine-tuned, and after re-tracking to the position where laser detector A detects the strongest reflected laser, the light spot diameter continues to be reduced until the light spot size can just cover the optical response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector A, the power of laser emitter A is adjusted through an algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements of its normal operation. Then, laser emitter A is turned off, and a message is sent to laser emitter B that the alignment of laser emitter A is completed. At the communication receiving end, after the photoelectric XOR logic gate detects a sudden drop in the light response signal, it confirms that the alignment of laser reflector A is complete, then opens the laser reflection baffle, keeps the position and direction of the photoelectric XOR logic gate unchanged, and waits for alignment with laser emitter B; At the communication transmitting end, after receiving the message from laser transmitter A that the alignment is complete, laser transmitter B starts laser transmitter B and keeps the laser transmitting power unchanged. With the assistance of the positioning system, the laser of laser transmitter B is emitted in the direction of the photoelectric XOR logic gate at the communication receiving end. According to the distance between the communication transmitting end and the communication receiving end, laser beam expander B is adjusted so that the laser spot irradiated on the communication receiving end is larger than the positioning system accuracy, ensuring that the laser spot can cover the photoelectric XOR logic gate. At the communication receiving end, after the photoelectric XOR logic gate is irradiated by the laser emitted by laser emitter B, the photoelectric XOR logic gate shows an obvious surge in light response signal, which means that laser emitter B is trying to align with it. Then, the direction remains unchanged and moves along the normal direction of the photoelectric XOR logic gate, that is, the laser emission direction of laser emitter A, to the position where the light response signal is the strongest. Then, the position remains unchanged and rotates to the direction where the light response signal is the strongest. The position and direction are then recorded. At this time, the laser is incident along the normal direction of the photoelectric XOR logic gate, and then the laser reflection baffle is repeatedly opened and closed at a frequency f, reflecting the laser back to the laser detector B at the communication transmitting end at a frequency f.

8. The application method according to claim 7, characterized in that: At the communication transmitting end, after laser detector B receives the reflected signal with a frequency of f, it adjusts laser beam expander B to reduce the diameter of the laser spot. During this process, if the intensity of the reflected laser light received by laser detector B decreases, it means that the light spot has deviated from the light response area of ​​the photoelectric XOR logic gate. The reduction of the light spot diameter is stopped, the emission angle of laser emitter B is maintained unchanged, the position of laser emitter B is fine-tuned, and the laser detector B is re-tracked. After detecting the position of the strongest reflected laser, the spot diameter continues to shrink until the spot size can just cover the optical response area of ​​the photoelectric XOR logic gate. Then, according to the intensity of the reflected laser light received by laser detector B, the power of laser emitter B is adjusted through the algorithm to ensure that the light intensity received by the photoelectric XOR logic gate can meet the requirements for its normal operation. Then, laser emitter B is turned off, and a message is sent to laser emitter A that laser emitter B has been aligned. At the communication transmitting end, after receiving the message from laser transmitter B that the alignment is complete, laser transmitter A starts laser transmitter A and keeps the laser transmitting power unchanged; At the communication receiving end, the photoelectric XOR logic gate detects a sudden drop in the light response signal, confirming that the alignment of laser emitter B is complete. After that, the position remains unchanged. Through algorithm calculation, the normal angle of the photoelectric XOR logic gate is adjusted to be exactly at the center position of the two laser beams of laser A and laser B, ensuring that the incident angles of the two laser beams are consistent. At this time, the laser emitted by laser emitter A is reflected by the laser reflection baffle at a frequency f to laser detector B. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value when the photoelectric XOR logic gate input is (1, 0); At the communication transmitting end, laser detector B receives the reflected laser of frequency f, confirms that all alignment and calibration are complete, and then starts laser transmitter B, notifying laser transmitter A through the reflected signal that all alignment and calibration are complete. At the communication transmitter, laser detector A receives the reflected laser light of frequency f, confirming that all alignment and corrections have been completed. At the communication receiving end, the photoelectric XOR logic gate changes from being illuminated by laser emitter A alone to being illuminated by laser emitter A and laser emitter B together. The light response signal suddenly drops, confirming that both laser emitter A and laser emitter B are aware that all alignment and calibration have been completed. The output signal value of the photoelectric XOR logic gate at this time is recorded, that is, the output signal value when the input of the photoelectric XOR logic gate is (1, 1). Then, the threshold of the photoelectric XOR logic gate is set to be greater than the output signal value when the input is (1, 1) and less than the output signal value when the input is (1, 0). Then, the laser reflection baffle is opened, and the transmission of remote laser encrypted information is waited for. At this time, the reflection of the laser emitted by the communication transmitting end will be greatly weakened, and the frequency becomes 0. At the communication transmitting end, the reflected laser received by laser detector A and laser detector B suddenly drops and the frequency drops to 0, confirming that the photoelectric XOR logic gate is working normally and starts sending remote laser encrypted information.

9. The application method according to claim 8, characterized in that: The switching frequency f of the laser reflection baffle is determined by the response speeds of the photoelectric XOR logic gate, laser detector A, and laser detector B, and satisfies the condition that 1 / f is greater than the response speed.

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