Multi-aperture coherent synthetic laser communication system common phase transmission method

Abstract

The application provides a kind of multi-aperture coherent synthesis laser communication system common phase emission method, through a polarizing beam splitter, the transmitting light path and the receiving light path are separated, another polarizing beam splitter is used to combine the beams of the transmitting light path and the receiving light path; converging lens and optical power meter are used to monitor the combined beam power of the transmitting light path and the receiving light path, by controlling the phase shifter in the transmitting light path, the combined beam power is maximized, the beams of the transmitting light path and the receiving light path are in phase; on the basis of coherent synthesis of laser receiving beams between each aperture, the common phase emission of laser is realized. The application increases the sighting scope in the transmitting light path, which can compensate and correct the emission pointing error caused by the tangential relative velocity between two laser terminals, reduce the power loss caused by alignment mismatch, thereby improve the range of multi-aperture coherent synthesis laser communication system, which can be widely used in inter-satellite, satellite-ground, air-to-air, air-to-ground and other space laser communication links.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of transmission, in particular to a multi-aperture coherent synthesis laser communication system common phase transmission method. BACKGROUND

[0002] The multi-aperture coherent synthesis laser communication system can not only expand the receiving area through aperture splicing, but also improve the transmission distance of the laser communication system and reduce the communication error rate.

[0003] The CN115567115A patent application provides a multi-aperture coherent synthesis technology and system, which overcomes the influence of the response time of the large deflection angle optical phased array on the interruption of laser communication through the time-sharing control of the angle deflection of the optical phased array of each aperture, and realizes continuous and uninterrupted high-speed communication of the large deflection angle optical phased array laser communication. The system adopts a receive-transmit common optical path technology, which ensures the common phase reception of multiple apertures and simultaneously realizes common phase transmission.

[0004] However, due to the receive-transmit common optical path design, the system cannot overcome the influence of the lead angle caused by the tangential relative motion and time delay. Only by expanding the laser emission beam divergence angle to ensure that the transmitted laser beam covers the receiving terminal of the other party and the relative central spot irradiance decreases by no more than 1dB, the emission beam divergence angle is required to be greater than 6-8 times the lead angle, and the increase of the emission beam divergence angle will cause a significant decrease in the communication distance of the system.

[0005] The traditional multi-aperture common phase transmission adopts a target in-loop coherent synthesis technology (Research on Fiber Laser Target In-Loop Coherent Synthesis Technology, Doctoral Dissertation of National University of Defense Technology), the biggest feature of which is to take the laser power reflected from the target as the evaluation function. This method can better overcome the influence of atmospheric turbulence, but is affected by many factors such as the characteristics of the transmitted beam, the characteristics of the channel medium, and the characteristics of the target. Especially for the laser communication system, due to the long communication distance, the light power reflected by the target is very weak, and it is difficult to monitor the power, which makes this method unsuitable for long-distance laser communication systems.

[0006] Therefore, a multi-aperture coherent synthesis laser communication system is needed that can overcome the influence of the lead angle caused by the tangential relative motion and time delay. SUMMARY

[0007] The present application is to solve the influence of the lead angle caused by the tangential relative motion and time delay in the multi-aperture coherent synthetic laser communication system, and provides a multi-aperture coherent synthetic laser communication system common phase transmitting method, which separates the transmitting light path and the receiving light path in the multi-aperture coherent synthetic laser communication system through a polarization beamsplitter, and has an advance collimator and a phase shifter in the transmitting light path, has a beam collecting system and a mirror in the receiving light path, and combines the beams of the transmitting light path and the receiving light path through another polarization beamsplitter; converging lenses and an optical power meter are used to monitor the combined beam power of the transmitting light path and the receiving light path, the phase shifter in the transmitting light path is controlled to make the combined beam power maximum, and the beams of the transmitting light path and the receiving light path are common phase; since the multi-aperture coherent synthetic laser communication system has realized the coherent synthesis of the laser receiving beams between the apertures, the common phase transmission of the laser can be realized. The advance collimator added in the transmitting light path can compensate and correct the transmission pointing error caused by the tangential relative velocity between the two laser terminals, reduce the power loss caused by the alignment mismatch, and thus improve the action distance of the multi-aperture coherent synthetic laser communication system, which can be widely applied to the space laser communication links such as inter-satellite, satellite-ground, air-to-air, air-to-ground and the like.

[0008] The present application provides a multi-aperture coherent synthetic laser communication system common phase transmitting method, which comprises the following steps:

[0009] S1, setting the aperture transmitting light path and the aperture receiving light path, the aperture transmitting light path and the aperture receiving light path each comprise a coupling collimator, an electrically controlled 1 / 4 wave plate, a first polarization beamsplitter, an advance collimator, an optical phase shifter, a beam collecting system, a mirror, a second polarization beamsplitter, a converging lens, an optical power meter, and a phase shift controller, the coupling collimator is optically connected with the output end of a laser transmitting unit in sequence, the first polarization beamsplitter is optically connected with the output end of the coupling collimator in sequence, the advance collimator is optically connected with the reflection output end of the first polarization beamsplitter, the optical phase shifter is optically connected with the transmission output end of the first polarization beamsplitter, the beam collecting system is optically connected with the transmission output end of the first polarization beamsplitter, the mirror is optically connected with the transmission output end of the beam collecting system, the second polarization beamsplitter is optically connected with the reflection output end of the mirror and the output end of the optical phase shifter, the converging lens is optically connected with the transmission output end of the second polarization beamsplitter in sequence, the optical power meter is optically connected with the converging lens, the phase shift controller is electrically connected with the optical power meter, and the phase shift controller is electrically connected with the optical phase shifter; the reflection end of the second polarization beamsplitter is optically connected with an antenna unit, and the coupling collimator is optically connected with a coherent synthesis unit of a multi-aperture coherent synthetic laser communication system;

[0010] The transmitting light path comprises a laser transmitting unit, a coupling collimator, an electrically controlled 1 / 4 wave plate, a first polarization beamsplitter, an advance collimator, an optical phase shifter, a second polarization beamsplitter and an antenna unit;

[0011] The receiving light path comprises an antenna unit, a second polarization beamsplitter, a mirror, a beam collecting system, a first polarization beamsplitter, an electrically controlled 1 / 4 wave plate and a coupling collimator in sequence;

[0012] S2, before communication, the transmitting light path and the receiving light path of each aperture are subjected to equal phase calibration, the laser transmitting unit transmits linearly polarized light, the phase delay of the electrically controlled 1 / 4 wave plate is pi / 2, the optical power meter monitors the combined light power reaching the converging lens through the transmitting light path and the receiving light path respectively in real time and feeds back the monitoring result to the phase controller, and the phase controller controls the optical phase shifter so that the light passing through the transmitting light path and the receiving light path is in phase;

[0013] S3, the multi-aperture coherent synthesis laser communication system starts communication, the phase delay of the electrically controlled 1 / 4 wave plate is 0, the laser transmitting unit transmits linearly polarized light and outputs to the antenna unit through the transmitting light path of each aperture for in-phase transmission, and a multi-aperture coherent synthesis laser communication system in-phase transmission method is completed.

[0014] The multi-aperture coherent synthesis laser communication system in-phase transmission method, as a preferred mode, in the transmitting light path, the linearly polarized light passes through the coupling collimator, the electrically controlled 1 / 4 wave plate in turn, is reflected by the polarization beam splitter, and then passes through the pre-aiming mirror and the optical phase shifter in turn to reach the second polarization beam splitter, and the second polarization beam splitter reflects the linearly polarized light to the antenna unit.

[0015] The multi-aperture coherent synthesis laser communication system in-phase transmission method, as a preferred mode, in the receiving light path, the optical signal is transmitted to the mirror through the second polarization beam splitter, is reflected by the mirror after passing through the mirror, is collected by the collection system to match the transmitting light path, and finally passes through the first polarization beam splitter and then passes through the electrically controlled 1 / 4 wave plate and the coupling collimator to be coupled to the coherent synthesis unit.

[0016] The multi-aperture coherent synthesis laser communication system in-phase transmission method, as a preferred mode, the coupling collimator couples the spatial light to the single-mode optical fiber, and the electrically controlled 1 / 4 wave plate is a wave plate control device capable of realizing phase delay 0 and pi / 2 switching.

[0017] The multi-aperture coherent synthesis laser communication system in-phase transmission method, as a preferred mode, the electrically controlled 1 / 4 wave plate is a liquid crystal electrically controlled 1 / 4 wave plate.

[0018] The multi-aperture coherent synthesis laser communication system in-phase transmission method, as a preferred mode, the first polarization beam splitter and the second polarization beam splitter separate the transmitting light path and the receiving light path.

[0019] The first polarization beam splitter and the second polarization beam splitter are polarization beam splitter prisms or polarization beam splitter plates with an extinction ratio of >1000:1.

[0020] The multi-aperture coherent synthetic laser communication system common phase emission method of the application, as a preferred mode, the pre-aiming mirror is used for correcting the lead angle, and the pre-aiming mirror is a piezoelectric ceramic fast mirror or a voice coil motor fast mirror or a liquid crystal mirror.

[0021] The phase shifter is a liquid crystal phase shifter or a piezoelectric ceramic phase shifter.

[0022] The multi-aperture coherent synthetic laser communication system common phase emission method of the application, as a preferred mode, the magnification of the converging system is the ratio of the focal length of the emission light path to the focal length of the receiving light path in the system design.

[0023] The mirror is a plane mirror.

[0024] The converging lens is a single-piece convex lens or a combined lens group.

[0025] The multi-aperture coherent synthetic laser communication system common phase emission method of the application, as a preferred mode, the optical power meter is a PIN photodiode or an APD photodiode.

[0026] The multi-aperture coherent synthetic laser communication system common phase emission method of the application, as a preferred mode, the phase shift controller controls the optical path difference of the emission light path and the receiving light path and ensures that the optical path difference of the emission light path and the receiving light path of each aperture is the same.

[0027] The control algorithm used by the phase shift controller is any one of the following: random parallel gradient algorithm, hill climbing method, multi-dithering method, single-dithering method, genetic algorithm, evolution algorithm and neural network algorithm.

[0028] The application has important application prospects in the fields of free space laser communication and laser radar.

[0029] The technical scheme of the application is a multi-aperture coherent synthetic laser communication system common phase emission method, which comprises a coupling collimator, an electrically controlled 1 / 4 wave plate, a first polarization beam splitter, a pre-aiming mirror, an optical phase shifter, a converging system, a mirror, a second polarization beam splitter, a converging lens, an optical power meter and a phase shift controller.

[0030] Before communication, the phase of the transmitting and receiving light paths of each aperture is calibrated. During calibration, the laser transmitting unit transmits linearly polarized light, which passes through the coupling collimator. At this time, the phase delay of the electrically controlled 1 / 4 wave plate is controlled to be π / 2. After the light beam passes through the electrically controlled 1 / 4 wave plate, the linearly polarized light becomes circularly polarized light. Part of the light enters the transmitting light path, and the other part enters the receiving light path. The light entering the transmitting light path passes through the pre-aiming mirror and the phase shifter, and most of the light is reflected by the second polarizing beam splitter, and a small part of the light is transmitted to the converging lens. The light entering the receiving light path passes through the converging system and the mirror, and most of the light is transmitted through the second polarizing beam splitter, and a small part of the light is reflected by the polarizing beam splitter to the converging lens. The two beams of light reaching the converging lens converge on the optical power meter. The optical power meter monitors the combined light power in real time and feeds back the monitoring results to the phase shift controller to control the optical phase shifter, so that the light beams passing through the transmitting and receiving light paths are in phase.

[0031] During communication, the phase delay of the electrically controlled 1 / 4 wave plate is controlled to be 0. The laser transmitting unit transmits linearly polarized light, which passes through the coupling collimator and the electrically controlled 1 / 4 wave plate and remains linearly polarized. The light is reflected by the first polarizing beam splitter to the transmitting light path, passes through the pre-aiming mirror and the optical phase shifter, reaches the second polarizing beam splitter, and is reflected by the second polarizing beam splitter to the antenna unit of the system. The antenna unit receives the optical signal, transmits it through the second polarizing beam splitter, reflects it by the mirror of the receiving light path, converges it by the converging system to match the transmitting light path, and finally transmits it through the first polarizing beam splitter and the electrically controlled 1 / 4 wave plate, and is coupled to the coherent synthesis unit of the multi-aperture coherent synthesis laser communication system through the coupling collimator. Because the receiving light of each aperture is in phase through coherent synthesis, and the transmitting and receiving light paths of each aperture are calibrated in phase before communication, the in-phase transmission of the optical phased array antenna unit of each aperture is realized.

[0032] In some embodiments, the coupling collimator can couple spatial light to a single-mode optical fiber, and the aperture and focal length of the coupling collimator meet the maximum efficiency requirement of fiber coupling.

[0033] In some embodiments, the electrically controlled 1 / 4 wave plate can be a liquid crystal electrically controlled 1 / 4 wave plate, and other wave plate control devices that can realize phase delay switching between 0 and π / 2.

[0034] In some embodiments, the first polarizing beam splitter and the second polarizing beam splitter can be polarizing beam splitter prisms and polarizing beam splitter plates, and the extinction ratio is >1000:1.

[0035] In some embodiments, the pre-aiming mirror can be a piezoelectric ceramic fast mirror, a voice coil motor fast mirror, a liquid crystal mirror, etc.

[0036] In some embodiments, the phase shifter can be a liquid crystal phase shifter, a piezoelectric ceramic phase shifter, or other spatial phase modulators.

[0037] In some embodiments, the magnification of the condensing system is the ratio of the focal length of the transmitting optical path to the focal length of the receiving optical path designed for the system.

[0038] In some embodiments, the reflecting mirror is a plane reflecting mirror.

[0039] In some embodiments, the converging lens can be a single piece convex lens or a combined lens group.

[0040] In some embodiments, the optical power meter can be a PIN photodiode, an APD photodiode, or other detector, and the working wavelength range of the optical power meter should cover the wavelength of the transmitted signal light.

[0041] In some embodiments, the control algorithm used by the phase control unit includes but is not limited to random parallel gradient algorithm, hill climbing method, multi-dithering method, single-dithering method, genetic algorithm, evolutionary algorithm, neural network algorithm, etc.

[0042] The present application has the following advantages:

[0043] (1) According to the difference in polarization characteristics of the transmitting and receiving beams, the present application uses a polarization beam splitter to separate the transmitting optical path and the receiving optical path of the multi-aperture coherent synthesis laser communication system, controls the optical path difference between the transmitting optical path and the receiving optical path through phase shifting technology, and ensures that the optical path difference of each aperture is consistent. When the laser communication system coherently synthesizes the reception of each aperture, it also realizes the common phase transmission.

[0044] (2) The present application uses multi-aperture coherent synthesis laser communication system common phase transmission, increases the pre-aiming mirror in the transmitting optical path to correct the pre-angle, which can greatly reduce the alignment mismatch loss of laser transmission and improve the action distance of the laser communication system. BRIEF DESCRIPTION OF DRAWINGS

[0045] Fig. 1 It is a flow chart of a multi-aperture coherent synthesis laser communication system common phase transmission method.

[0046] Fig. 2 It is a transmitting and receiving block diagram of a multi-aperture coherent synthesis laser communication system.

[0047] REFERENCE NUMERALS:

[0048] 1, coupling collimator; 2, electrically controlled 1 / 4 wave plate; 3, first polarization beam splitter; 4, pre-aiming mirror; 5, optical phase shifter; 6, condensing system; 7, reflecting mirror; 8, second polarization beam splitter; 9, converging lens; 10, optical power meter; 11, phase shifting controller. DETAILED DESCRIPTION

[0049] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0050] Example 1

[0051] like Figs. 1-2 As shown, a coherent phase emission method for a multi-aperture coherent synthesized laser communication system is disclosed. The optical path of the multi-aperture coherent synthesized laser communication system includes: a coupler collimator 1, an electrically controlled quarter-wave plate 2, a first polarizing beam splitter 3, a pre-aiming mirror 4, an optical phase shifter 5, a beam-gathering system 6, a reflector 7, a second polarizing beam splitter 8, a converging lens 9, an optical power meter 10, and a phase-shifting controller 11. The emission optical path includes: a laser emission unit, a coupler collimator 1, an electrically controlled quarter-wave plate 2, a first polarizing beam splitter 3, a pre-aiming mirror 4, an optical phase shifter 5, a second polarizing beam splitter 8, and an antenna unit.

[0052] The receiving optical path includes, in sequence, an antenna unit, a second polarizing beam splitter 8, a reflector 7, a beam-gathering system 6, a first polarizing beam splitter 3, an electrically controlled quarter-wave plate 2, and a coupling collimator 1.

[0053] The first step is to perform phase calibration on the transmitting and receiving optical paths of each aperture before communication. During calibration, the laser transmitting unit emits linearly polarized light, which passes through the coupling collimator 1. At this time, the phase delay of the electrically controlled quarter-wave plate 2 is controlled to be π / 2. After passing through the electrically controlled quarter-wave plate, the beam changes from linearly polarized light to circularly polarized light. After passing through the first polarizing beam splitter 3, part of the beam enters the transmitting optical path, and the other part enters the receiving optical path. The light entering the transmitting optical path passes through the pre-aiming reflector 4 and the optical phase shifter 5. Most of it is reflected by the second polarizing beam splitter 8, and a small part is transmitted to the converging lens 9. The light entering the receiving optical path passes through the beam-gathering system 6 and the reflector 7. Most of it is transmitted through the second polarizing beam splitter 8, and a small part is reflected by the second polarizing beam splitter 8 to the converging lens 9. The two beams reaching the converging lens converge to the optical power meter 10. The optical power meter monitors the combined optical power in real time and feeds back the monitoring results to the phase controller 11 to control the optical phase shifter 5 so that the optical path difference between the transmitting and receiving optical paths is an integer multiple of the wavelength.

[0054] Second step, the phase delay of the electrically controlled 1 / 4 wave plate 2 is 0 during communication. The laser emitting unit emits linearly polarized light, which is still linearly polarized light after passing through the coupling collimator 1 and the electrically controlled 1 / 4 wave plate 2, is reflected by the first polarizing beam splitter 3 to the emitting light path, is reflected by the pre-aiming mirror 4 and the optical phase shifter 5, reaches the second polarizing beam splitter 8, and is reflected by the second polarizing beam splitter 8 to the antenna unit of the system. The antenna unit receives the light signal, transmits through the second polarizing beam splitter 8, is reflected by the reflecting mirror 7 of the receiving light path, is collected by the collection system 6 to match the emitting light path, and finally transmits through the first polarizing beam splitter 3 and the electrically controlled 1 / 4 wave plate 2, is coupled to the coherent synthesis unit of the multi-aperture coherent synthesis laser communication system through the coupling collimator 1. The received light of each aperture of the system is equal in phase through coherent synthesis, and the emitting light path and the receiving light path of each aperture are equal in phase before communication, so that the co-phase emission of the optical phased array antenna unit of each aperture can be realized.

[0055] In the embodiment, the first polarizing beam splitter 3 separates the emitting light path and the receiving light path in the multi-aperture coherent synthesis laser communication system, the pre-aiming mirror 4 and the phase shifter 5 are arranged in the emitting light path, the collection system 6 and the reflecting mirror 7 are arranged in the receiving light path, the second polarizing beam splitter 8 is used to combine the beams of the emitting light path and the receiving light path, the converging lens 9 and the optical power meter 10 are used to monitor the combined light power passing through the emitting light path and the receiving light path, the phase shifter 5 in the emitting light path is controlled to make the combined light power maximum, and the beams of the emitting light path and the receiving light path are equal in phase. Since the multi-aperture coherent synthesis laser communication system has realized the coherent synthesis of the laser receiving beams between the apertures, the co-phase emission of the laser can be realized.

[0056] In the embodiment, the pre-aiming mirror 4 is arranged in the emitting light path, the emission pointing error caused by the tangential relative velocity between two laser terminals can be compensated and corrected, the power loss caused by the alignment mismatch is reduced, the effective distance of the multi-aperture coherent synthesis laser communication system is improved, and the multi-aperture coherent synthesis laser communication system can be widely applied to intersatellite, satellite-ground, air-to-air, air-to-ground and other space laser communication links.

[0057] In the embodiment, the model of the coupling collimator and the converging lens is F810FC-1550, NA=0.24, and f=37mm.

[0058] In the embodiment, the electrically controlled 1 / 4 wave plate is a liquid crystal 1 / 4 wave plate, the phase delay in the power-on state is π / 2, and the phase delay in the power-off state is 2π (0).

[0059] In the embodiment, the first polarizing beam splitter 3 and the second polarizing beam splitter 8 are both polarizing beam splitter prisms, reflect horizontally polarized light and transmit vertically polarized light, and the extinction ratio is greater than 1000:1.

[0060] In this embodiment, the foresight scope 4 is a PIS-330.2L fast mirror of piezoelectric ceramic type in Germany, the beam deflection range is 20 mrad, the resolution is 20 nrad, and the bandwidth is ≥400 Hz.

[0061] In this embodiment, the optical phase shifter 5 is a liquid crystal phase shifter, and the phase delay is achieved by applying different voltages to the liquid crystal. The size of the liquid crystal phase shifter is 40 mm×40 mm, and the applicable wavelength range is 1550 nm±2 nm.

[0062] In this embodiment, the scaling ratio of the condensing system 6 is 1:1; that is, it is a 4f optical system, the lens diameter is 10 mm, and the focal length is 20 mm.

[0063] In this embodiment, the mirror 7 is an optical plane mirror with a size of 30 mm.

[0064] In this embodiment, the optical power meter 10 is an InGaAs APD photodiode, the photosensitive area is 200 μm, the spectral response range is 1.0-1.65 μm, the responsivity is 10 A / W, and the multiplication factor M=10.

[0065] In this embodiment, the control algorithm used by the phase shift control unit is the hill climbing method.

[0066] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited to this. Any person skilled in the art, according to the technical solution and the inventive concept of the present application, can make equivalent replacement or change within the technical range disclosed by the present application, which should be covered in the protection scope of the present application.

Claims

1. A method for coherent co-phase transmission of a multi-aperture synthetic laser communication system, characterized in that: The method comprises the following steps: S1, setting each aperture transmitting light path and receiving light path, each aperture transmitting light path and receiving light path comprises coupling collimator (1), electrically controlled 1 / 4 wave plate (2), first polarization beam splitter (3) which are sequentially connected with the output end of laser emitting unit, pre-sighting mirror (4), optical phase shifter (5) which are sequentially connected with the reflection output end of the first polarization beam splitter (3), converging system (6), reflecting mirror (7) which are connected with the transmission output end of the first polarization beam splitter (3), second polarization beam splitter (8) which are connected with the reflection output end of the reflecting mirror (7) and the output end of the optical phase shifter (5), converging lens (9), optical power meter (10) and phase shifter controller (11) which are sequentially connected with the transmission output end of the second polarization beam splitter (8) and electrically connected with the optical power meter (10), the phase shifter controller (11) is electrically connected with the optical phase shifter (5), the reflection end of the second polarization beam splitter (8) is connected with the antenna unit, and the coupling collimator (1) is connected with the coherent synthesis unit of the multi-aperture coherent synthesis laser communication system; The transmitting light path comprises the laser emitting unit, the coupling collimator (1), the electrically controlled 1 / 4 wave plate (2), the first polarization beam splitter (3), the pre-sighting mirror (4), the optical phase shifter (5), the second polarization beam splitter (8) and the antenna unit. The receiving light path comprises the antenna unit, the second polarization beam splitter (8), the reflecting mirror (7), the converging system (6), the first polarization beam splitter (3), the electrically controlled 1 / 4 wave plate (2) and the coupling collimator (1) in sequence. S2, before communication, the transmitting light path and the receiving light path of each aperture are calibrated, the laser emitting unit emits linearly polarized light, the phase delay of the electrically controlled 1 / 4 wave plate (2) is π / 2, the optical power meter (10) monitors the synthesized light optical power after reaching the converging lens (9) through the transmitting light path and the receiving light path in real time and feeds back the monitoring result to the phase shifter controller (11), and the phase shifter controller (11) controls the optical phase shifter (5) to make the light passing through the transmitting light path and the receiving light path co-phased; S3, the multi-aperture coherent synthesis laser communication system starts communication, the phase delay of the electrically controlled 1 / 4 wave plate (2) is 0, the laser emitting unit emits linearly polarized light and outputs to the antenna unit through the transmitting light path of each aperture for co-phase emission, and a multi-aperture coherent synthesis laser communication system co-phase emission method is completed.

2. The method of Claim 1, wherein the method is a method of transmitting in phase by a multi-aperture coherent synthetic laser communication system, characterized in that: In the transmitting light path, the linearly polarized light sequentially passes through the coupling collimator (1), the electrically controlled 1 / 4 wave plate (2), is reflected by the polarization beam splitter (3), and then sequentially passes through the pre-sighting mirror (4) and the optical phase shifter (5) to reach the second polarization beam splitter (8), and the second polarization beam splitter (8) reflects the linearly polarized light to the antenna unit.

3. The method of Claim 1, wherein the method further comprises: The light signal is transmitted to the mirror (7) through the second polarization beamsplitter (8) in the receiving light path, and then reflected by the mirror (7) and collected by the collection system (6) to match the transmitting light path, and finally transmitted through the first polarization beamsplitter (3) and then sequentially through the electrically controlled 1 / 4 wave plate (2), the coupling collimator (1) and coupled to the coherent synthesis unit.

4. The method of Claim 1, wherein the method further comprises: The coupling collimator (1) couples spatial light to a single-mode optical fiber, and the electrically controlled 1 / 4 wave plate (2) is a wave plate control device capable of switching phase delay 0 and π / 2.

5. The method of Claim 4, wherein the common phase transmission method is used in a multi-aperture coherent synthetic laser communication system. The electrically controlled 1 / 4 wave plate (2) is a liquid crystal electrically controlled 1 / 4 wave plate.

6. The method of claim 1, wherein the method further comprises: The first polarization beamsplitter (3) and the second polarization beamsplitter (8) separate the transmitting light path and the receiving light path. The first polarization beamsplitter (3) and the second polarization beamsplitter (8) are polarization beamsplitter prisms or polarization beamsplitter lenses with an extinction ratio >1000:

1.

7. The method of Claim 1, wherein the method further comprises: The pre-sighting scope (4) corrects the lead angle, and the pre-sighting scope (4) is a piezoelectric ceramic fast mirror or a voice coil motor fast mirror or a liquid crystal mirror. The phase shifter (5) is a liquid crystal phase shifter or a piezoelectric ceramic phase shifter.

8. The method of Claim 1, wherein the method is a method of transmitting in phase by a multi-aperture coherent synthetic laser communication system, characterized in that: The magnification of the collection system (6) is the ratio of the focal length of the transmitting light path to the focal length of the receiving light path designed by the system. The mirror (7) is a plane mirror. The converging lens (9) is a single-piece convex lens or a combined lens group.

9. The method of Claim 1, wherein the common phase transmission method is used in a multi-aperture coherent synthetic laser communication system. The optical power meter (10) is a PIN photodiode or an APD photodiode.

10. The method of Claim 1, wherein the method is a method of transmitting in phase by a multi-aperture coherent synthetic laser communication system, characterized in that: The phase shifter controller (11) controls the optical path difference of the transmitting light path and the receiving light path and ensures that the optical path difference of the transmitting light path and the receiving light path of each aperture is the same. The control algorithm used by the phase shifter controller (11) is any one of the following: random parallel gradient algorithm, hill climbing method, multi-dithering method, single-dithering method, genetic algorithm, evolutionary algorithm and neural network algorithm.

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