CN117220774A

CN117220774A - Space laser communication system

Info

Publication number: CN117220774A
Application number: CN202311308718.2A
Authority: CN
Inventors: 罗先刚; 徐明峰; 陈双成; 蒲明博; 于泳
Original assignee: Tianfu Xinglong Lake Laboratory
Current assignee: Tianfu Xinglong Lake Laboratory
Priority date: 2023-10-10
Filing date: 2023-10-10
Publication date: 2023-12-12

Abstract

The embodiment of the application provides a space laser communication system, which relates to the field of space optical communication. The system comprises a signal sending system and a signal receiving system, wherein an optical modulation module is matched with a channel capacity expansion module, multiplexing of modulated light beams in multiple polarization states and a plurality of vector light fields is utilized, the polarized light fields are used as information carriers, the vector light fields are used as transmission modes, the number of parallel communication channels in space is increased, so that the capacity of communication information is improved, and capacity expansion is realized. Meanwhile, by adopting the high-energy pulse laser beam, a high-transmission channel can be opened for the information light field in cloud and fog weather by utilizing the space transmission characteristic (filamentation effect) of the high-energy pulse laser beam, so that the low-loss transmission of the information light field in cloud and fog conditions is ensured.

Description

Space laser communication system

Technical Field

The application relates to the technical field of space optical communication, in particular to a space laser communication system.

Background

The spatial laser communication technology uses laser light as carrier wave transmission information, and generally uses physical parameters such as wavelength, frequency, time, amplitude, phase and polarization of an optical signal to carry out signal mounting. In the prior art, conventional information carriers have been under development in the face of later high-capacity communications, and how to expand the information capacity in free optical communications has become an important problem in the field of spatial optical communications technology.

For spatial laser communication, information carriers such as amplitude, phase, polarization, etc. of a carrier signal in a free space channel may be interfered with by different spatial channel characteristics. For example, in turbulent environments, changes in the spatially localized refractive index will cause abrupt changes in the optical field phase, affecting the signal wavefront, ultimately forming bit error decisions in the signal. In addition, the channel environment in the free space channel has turbulence environment and also has interference of space particles such as rain and fog in the free environment, and scattering and absorption of particles such as rain and fog and dust in the space can cause attenuation of laser energy, so that the transmission characteristics of laser light in the space are interfered. How to ensure low-loss transmission of an information light field under a cloud and fog condition is also a critical problem in the technical field of space optical communication.

Disclosure of Invention

In order to overcome at least the above-mentioned drawbacks of the prior art, an object of the present application is to provide a spatial laser communication system.

In a first aspect, an embodiment of the present application provides a spatial laser communication system, where the spatial laser communication system includes a signal sending system and a signal receiving system;

the signal receiving system comprises a first receiving module, a channel recovery module, an optical demodulation module and a plurality of receivers;

the excitation light module is used for generating a laser beam;

the optical modulation modules are used for modulating signals of the signal sources to obtain modulated light beams with multiple polarization states;

the channel capacity expansion module is connected with the optical modulation module, and multiplexes a plurality of modulated light beams and a plurality of vector light fields to form a transmitted vector light beam;

the first signal sending module is respectively connected with the excitation light module and the channel capacity expansion module, and the sending vector light beam and the laser light beam are combined into a carrier light beam and then transmitted to the first receiving module;

the first receiving module is connected with the first receiving module and used for carrying out beam splitting treatment on the received carrier beam to obtain a corresponding received vector beam and a received laser beam;

the channel recovery module is connected with the first receiving module, and the channel recovery module carries out channel recovery processing on the received vector light beam to obtain an adjustable light beam;

the optical demodulation module is connected with the channel recovery module and is used for demodulating the adjustable light beam to obtain signals of a plurality of corresponding signal sources;

and the receivers are connected with the optical demodulation module and respectively receive signals of different signal sources.

In one possible implementation, the multiplexed modulated light beam is configured as a plurality of modulated light beam groups, and the channel expansion module includes a channel expansion sub-module corresponding to the plurality of modulated light beam groups;

the channel expansion Rong Zi module is used for multiplexing the modulated light beams with different polarization states in each modulated light beam group with a plurality of vector light fields to form two paths of corresponding column vector light beams.

In one possible implementation, the channel expansion submodule includes a polarizing component and a swirl slide;

the polarization component is used for spatially combining the modulated light beams with different polarizations in the modulated light beam group to obtain polarized light beams;

the vortex slide is used for converting the polarized light beams with orthogonal polarization states to generate two paths of orthogonal column vector light beams.

In one possible implementation, the modulated light beam group includes a first modulated light beam and a second modulated light beam with different polarization states, and the channel expansion Rong Zi module further includes a total reflection component;

the total reflection assembly is connected with the polarization assembly and is used for total reflecting the first modulated light beam into the polarization assembly;

the polarization component is used for spatially combining the first modulated light beam and the second modulated light beam to obtain a polarized light beam with an orthogonal polarization state.

In a possible implementation manner, the channel capacity expansion module further comprises a first beam combining sub-module connected with each channel capacity expansion sub-module, wherein the first beam combining sub-module is used for combining the column vector beams generated by the channel capacity expansion sub-modules into the transmission vector beam.

In one possible implementation manner, the signal sending system further comprises a control module, and the optical modulation module comprises an optical coupling sub-module and an optical modulation sub-module;

the optical coupling sub-module is connected with the plurality of signal sources and is used for coupling signals with different wavelengths of the plurality of signal sources to obtain coupling signals;

the optical modulation submodule is respectively connected with the optical coupling submodule and the control module, and is used for modulating the coupling signals to obtain multiple paths of corresponding modulated light beams transmitted in the space light field, and the polarization states of the modulated light beams are regulated according to the voltage signals of the control module.

In one possible implementation manner, the first signal sending module comprises a second beam combining sub-module, and the first receiving module comprises a first beam splitting sub-module;

the second beam combining submodule is respectively connected with the excitation light module and the channel capacity expansion module, and is used for combining a plurality of transmission vector beams and the laser beams into carrier beams and transmitting the carrier beams to the first receiving module;

the first beam splitting submodule is used for carrying out beam splitting treatment on the received carrier beam to obtain a corresponding received vector beam and a corresponding received laser beam.

In one possible implementation, the channel recovery module includes a second beam splitting module and a plurality of channel recovery sub-modules;

the second beam splitting module is respectively connected with the first receiving module and the plurality of channel recovery submodules and is used for splitting the received vector beam to obtain a plurality of corresponding orthogonal column vector beams;

the channel recovery submodule is used for carrying out channel recovery processing on the orthogonal column vector light beams to obtain adjustable light beams.

In one possible implementation, the channel recovery submodule includes a recovery polarization component and a recovery vortex slide;

the recovery vortex slide is used for converting two paths of orthogonal column vector beams to generate corresponding polarized beams;

the polarization recovery assembly is used for splitting the polarized light beam into two paths of adjustable light beams.

In one possible implementation, the optical demodulation module includes an optical decoupling sub-module and an optical demodulation sub-module;

the optical demodulation sub-module is connected with the channel recovery sub-module, demodulates the adjustable light beams, and converts the multi-path adjustable light beams transmitted in the space light field into corresponding decoupled signals;

the optical decoupling submodule is respectively connected with the optical demodulation submodule and a plurality of receivers, and is used for decoupling the decoupling signals to obtain signals of a plurality of corresponding signal sources.

In one possible implementation manner, the signal receiving system further comprises a beam quality analysis module, a state monitoring module, a feedback modulation module and a second signal sending module, and the signal sending system further comprises a second signal receiving module and a data extraction module;

the beam quality analysis module is respectively connected with the first beam splitting sub-module and the feedback modulation module and is used for carrying out quality analysis on the received laser beam to obtain a first data signal;

the state monitoring module is respectively connected with the receivers and the feedback modulation module and is used for detecting signals of the plurality of signal sources received by the receivers to obtain second data signals;

the feedback modulation module modulates the first data signal and the second data signal, and combines the received laser beam with the modulated first data signal and the modulated second data signal to obtain a feedback beam;

the second signal sending module is connected with the feedback modulation module and is used for sending the feedback light beam to the second signal receiving module;

the data extraction module is respectively connected with the second signal receiving module and the control module and is used for extracting information in the feedback light beam received by the second signal receiving module and sending the extracted information to the control module.

In one possible implementation, the feedback modulation module further includes a feedback modulation sub-module, a feedback vortex slide, and a feedback beam combining assembly;

the feedback modulation sub-module is used for converting the first data signal and the second data signal into data beams transmitted on a spatial light field;

the feedback vortex slide is used for converting the data light beam into a feedback column vector light beam;

the feedback beam combining component is used for combining the feedback column vector beam with the receiving laser beam to obtain a feedback beam.

Based on any one of the above aspects, the spatial laser communication system provided by the embodiment of the application includes a signal receiving system and a signal receiving system, and the optical modulation module is matched with the channel capacity expansion module, that is, multiplexing of modulated light beams with multiple polarization states and multiple vector light fields is utilized, the polarized light fields are used as information carriers, and the vector light fields are used as transmission modes, so that the number of parallel communication channels in space is increased to improve the capacity of communication information, and capacity expansion is realized. Meanwhile, by adopting the high-energy pulse laser beam, a high-transmission channel can be opened for the information light field in cloud and fog weather by utilizing the space transmission characteristic (filamentation effect) of the high-energy pulse laser beam, so that the low-loss transmission of the information light field in cloud and fog conditions is ensured.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following description will briefly explain the drawings required for the embodiments, it being understood that the following drawings illustrate only some embodiments of the present application and are therefore not to be considered limiting of the scope, and that other related drawings may be obtained according to these drawings without the inventive effort of a person skilled in the art.

FIG. 1 is a block diagram of one possible function of a spatial laser communication system according to an embodiment of the present application;

FIG. 2 is a schematic diagram of one possible configuration of the signaling system of FIG. 1;

fig. 3 is a schematic diagram of another possible configuration of the signal receiving system of fig. 1.

Detailed Description

For the purpose of making the objects, technical solutions and advantages of the embodiments of the present application more apparent, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments of the present application. The components of the embodiments of the present application generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the application, as presented in the figures, is not intended to limit the scope of the application, as claimed, but is merely representative of selected embodiments of the application. All other embodiments, which can be made by those skilled in the art based on the embodiments of the application without making any inventive effort, are intended to be within the scope of the application.

It should be noted that: like reference numerals and letters denote like items in the following figures, and thus once an item is defined in one figure, no further definition or explanation thereof is necessary in the following figures.

In the description of the present application, it should be noted that, the azimuth or positional relationship indicated by the terms "upper", "lower", etc. are based on the azimuth or positional relationship shown in the drawings, or the azimuth or positional relationship that is commonly put in use of the product of the application, are merely for convenience of describing the present application and simplifying the description, and do not indicate or imply that the device or element to be referred to must have a specific azimuth, be configured and operated in a specific azimuth, and therefore should not be construed as limiting the present application. Furthermore, the terms "first," "second," and the like, are used merely to distinguish between descriptions and should not be construed as indicating or implying relative importance.

In the description of the present application, it should also be noted that, unless explicitly specified and limited otherwise, the terms "disposed," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present application can be understood by those of ordinary skill in the art in specific cases.

It should be noted that, in the case of no conflict, different features in the embodiments of the present application may be combined with each other.

Referring to fig. 1, the present application provides a spatial laser communication system 10, which includes a signal transmission system 100 and a signal reception system 200, wherein the signal transmission system 100 includes an excitation light module 110, a plurality of signal sources 120, an optical modulation module 130, a channel expansion module 140 and a first signal transmission module 150, and the signal reception system 200 includes a first reception module 210, a channel recovery module 220, an optical demodulation module 230 and a plurality of receivers 240.

The excitation light module 110 is configured to generate a laser beam, where the laser beam may be a high-power tunable pulse laser, and a filament effect of the laser beam may be used to open a high-transmission channel for an information light field in a cloud and fog weather, so as to ensure low-loss transmission of the information light field in the cloud and fog condition. Illustratively, the excitation optical module 110 may employ a high-energy pulse laser in the 800nm band to provide a high-power pulse laser carrier for the spatial laser communication system 10 in an embodiment of the present application.

The plurality of signal sources 120 are connected to the optical modulation module 130, and the optical modulation module 130 is configured to modulate signals from the plurality of signal sources 120 to obtain modulated light beams with multiple polarization states, where the polarized light field can be used as an information carrier. It should be noted that the signals of the plurality of signal sources 120 may carry the same information or may carry different information. Furthermore, the multiplexed light beam can be freely transmitted in the spatial light field, and the amplitude distribution of its cross section complies with the gaussian function.

The channel expansion module 140 is connected to the optical modulation module 130, and multiplexes the multiplexed light beam with a plurality of vector light fields to form a transmission vector light beam.

In the above configuration, the spatial laser communication system 10 uses the polarized light field as an information carrier and the vector light field as a transmission mode, so as to increase the number of parallel communication channels in space to increase the capacity of communication information, thereby realizing simultaneous transmission of multiple channels of information in free space and realizing capacity amplification.

The first signal transmitting module 150 is connected to the excitation light module 110 and the channel capacity expansion module 140, and combines the transmission signal beam and the laser beam into a carrier beam and transmits the carrier beam to the first receiving module 210.

The first receiving module 210 is configured to perform beam splitting processing on the received carrier beam, so as to obtain a corresponding received signal beam and a received laser beam.

The channel recovery module 220 is connected to the first receiving module 210, and the channel recovery module 220 performs channel recovery processing on the received signal beam to obtain a recovered beam.

The optical demodulation module 230 is connected to the signal recovery module, and demodulates the recovered light beam to obtain signals of the plurality of signal sources 120.

The plurality of receivers 240 are connected to the optical demodulation module 230 to receive signals from the different signal sources 120, respectively.

In this embodiment, the optical modulation module 130 and the channel capacity expansion module 140 are adopted, that is, multiplexing of modulated light beams with multiple polarization states and multiple vector light fields is utilized, the polarized light fields are used as information carriers, the vector light fields are used as transmission modes, so that the number of parallel communication channels in space is increased to improve the capacity of communication information, and capacity expansion is realized. Meanwhile, by adopting the high-energy pulse laser beam, a high-transmission channel can be opened for the information light field in cloud and fog weather by utilizing the space transmission characteristic (filamentation effect) of the high-energy pulse laser beam, so that the low-loss transmission of the information light field in cloud and fog conditions is ensured.

Referring to fig. 2, in one possible implementation of the present embodiment, the multiple modulated light beams are configured into multiple modulated light beam groups, the channel expansion module 140 includes a channel expansion sub-module 141 corresponding to the multiple modulated light beam groups, and the channel expansion Rong Zi module 141 is configured to multiplex modulated light beams with different polarization states in each modulated light beam group with multiple vector light fields to form two corresponding column vector light beams.

It will be appreciated that the number of communication channels may be increased by increasing the number of modulated beam sets and the number of channel expansion Rong Zi modules 141, i.e. by changing the polarization state of the modulated beams and the number of vector light fields, to increase the number of column vector beams, thereby achieving information capacity expansion.

Further, the channel expander Rong Zi module 141 includes a polarizing component 1411 and a swirl slide 1412.

The polarization component 1411 is configured to spatially combine modulated light beams with different polarizations in the modulated light beam group to obtain polarized light beams with orthogonal polarization states. Illustratively, the polarization component 1411 may be a polarization dependent light splitting cube.

The swirling slide 1412 is used to convert the polarized light beam of the orthogonal polarization state to generate two orthogonal column vector light beams. Vortex waveplate 1412 has polarization dependent optical characteristics and may be used to generate a polarization state column vector beam, i.e., a Laguerre-Gaussian (LG) intensity distribution that converts the TEM00 mode Gaussian beam into a "hollow-bore type" beam, depending on the polarization state of the modulated beam. When the polarization component 1411 is used to change the modulated light beam into a 0-degree fast axis direction with the polarization direction parallel to the vortex plate 1412, the output light field is a radial polarized light beam; if the polarization direction of the modulated light beam is perpendicular to the 0 ° fast axis direction of the vortex plate 1412, the output light field mode is an angular vector light field. The principle is that when linearly polarized light of any angle passes through the vortex wave plate 1412, a generalized cylindrical vector light field can be generated.

The Jones matrix is utilized to represent the light field change, and the linear polarized light with horizontal linear polarization, vertical linear polarization and any angle respectively passes through the vortex wave plate to generate vector light field expression as follows:

(angular vector beam)

(radial vector beam)

In the above formula, θ refers to the angle between the vibration direction of the polarized component in the modulated light beam and the fast axis (or slow axis).

In this embodiment, a higher order column vector beam can be generated by varying the polarization state of the modulated beam and the number of vector light fields. Illustratively, higher order swirling slides 1412 may be added to generate higher order column vector beams, increasing the number of column vector beams, enabling information capacity amplification. For example, when the m channel expansion Rong Zi modules 141 employ the first, second, and third order swirl slides 1412, respectively, the m order swirl slides 1412 will generate 2m orthogonal column vector beams, i.e., 2m orthogonal channels, to achieve signal expansion.

Further, the modulated light beam set includes a first modulated light beam and a second modulated light beam with different polarization states, and preferably, the modulated light beam set includes a first modulated light beam and a second modulated light beam with orthogonal polarization states. The channel expander Rong Zi module 141 further includes a total reflection assembly, which is connected to the polarization assembly 1411, and is configured to totally reflect the first modulated light beam to the polarization assembly 1411, and the polarization assembly 1411 is configured to spatially combine the first modulated light beam and the second modulated light beam that are totally reflected to obtain a polarized light beam with an orthogonal polarization state. Illustratively, the total reflection component may be a total reflection mirror, and the polarization component 1411 may be a polarization-dependent light splitting cube, and may further ensure orthogonal polarization states of polarized light beams while spatially combining two modulated light beams of different polarization states.

Specifically, the spatial laser communication system 10 provided in the embodiment of the present application may include two modulated beam groups and two channel expansion Rong Zi modules 141 respectively using a first-order vortex slide 1412A and a second-order vortex slide 1412B, each modulated beam group corresponds to one channel expansion Rong Zi module 141, and each modulated beam group includes modulated beams having a polarization direction parallel to a 0 ° fast axis direction of the vortex wave plate and a polarization direction perpendicular to the 0 ° fast axis direction of the vortex wave plate. When two groups of modulated light beams with orthogonal polarization states pass through the two channel expansion Rong Zi module 141, two paths of orthogonal first-order column vector light beams and two paths of orthogonal second-order column vector light beams are generated, and four communication channels are formed.

Still further, the channel expansion module 140 further includes a first beam combining sub-module 142 connected to each of the channel expansion sub-modules 141, where the first beam combining sub-module 142 is configured to combine the column vector beams generated by the multiple channel expansion sub-modules 141 into a transmit vector beam. Illustratively, the first beam combining sub-module 142 may be a light splitting cube.

Referring to fig. 2 again, in one possible implementation of the present embodiment, the signal receiving system 100 further includes a control module 160, and the optical modulation module 130 includes an optical coupling sub-module 131 and an optical modulation sub-module 132.

The optical coupling sub-module 131 is connected to the plurality of signal sources 120, and couples signals of different wavelengths of the plurality of signal sources 120 to obtain a coupled signal. Illustratively, the optical coupling sub-module 131 may be a dense wavelength division multiplexer.

The optical modulation sub-module 132 is connected to the optical coupling sub-module 131 and the control module 160, and the optical modulation sub-module 132 is configured to modulate the coupling signal to obtain multiple paths of modulated light beams transmitted in the spatial light field, and adjust the polarization state of the modulated light beams according to the voltage signal of the control module 160, and in addition, the optical modulation sub-module 132 can also adjust the size of the output speckle and the size of the divergence angle, so as to realize flexible matching of the light spots under different distances. Illustratively, the optical modulation sub-module 132 may be a focal length adjustable collimator.

Referring to fig. 2 and 3 again, in one possible implementation manner of the present embodiment, the first signal sending module 150 includes a second beam combining sub-module 151, and the first receiving module 210 includes a first beam splitting sub-module 211.

The second beam combining sub-module 151 is connected to the excitation light module 110 and the channel capacity expansion module 140, and combines the multiple transmission vector beams and the laser beams into a carrier beam, and transmits the carrier beam to the first receiving module 210. The first beam splitting submodule 211 is configured to split the received carrier beam to obtain a corresponding received vector beam and a received laser beam, where the received vector beam is an information beam including signals sent by the plurality of signal sources 120. Illustratively, the second beam combining sub-module 151 and the first beam splitting sub-module 211 may be aperture auto-iris diaphragms, and may be coated with a metal film with high reflectivity on the reflecting surface thereof to achieve high reflectivity of the vector beam (transmitting vector beam or receiving vector beam) and maintain the polarization state of the beam.

In the structure, the multipath transmission vector light beams and the laser light beams are combined into carrier light beams to be transmitted in a space light field, namely, a polarized light field is used as an information carrier, the vector light field is used as a transmission mode, and a pulse light field is used as a channel stable field, so that low-loss transmission of the information light field under a cloud and fog condition can be ensured, the number of parallel communication channels in the space can be increased to improve the capacity of communication information, and capacity expansion is realized.

In addition, referring to fig. 2 again, in one possible embodiment, a focal length adjustable collimator 161 connected to the control module 160 is further included between the excitation light module 110 and the second beam combining sub-module 151, and the focal length adjustable collimator 161 adjusts the output speckle size and the divergence angle size of the laser beam according to the voltage signal of the control module 160.

Referring to fig. 3 again, in one possible implementation of the present embodiment, the channel recovery module 220 includes a second beam splitting module 222 and a plurality of channel recovery sub-modules 221.

The second beam splitting module 222 is connected to the first receiving module 210 and the plurality of channel recovery sub-modules 221, and is configured to split the received vector beam to obtain a plurality of corresponding orthogonal column vector beams. Illustratively, the second beam splitting module 222 may be a light beam splitting cube.

The channel recovery sub-module 221 is configured to perform channel recovery processing on the orthogonal column vector beam to obtain an adjustable beam.

Referring to fig. 3 again, in one possible embodiment, a filter 212 is further disposed between the second beam splitting module 222 and the first receiving module 210, for absorbing energy of the pulsed laser beam. The filter 212 may be an 800 nm-filter for absorbing energy of a pulsed laser beam in the 800 band, for example.

Further, the channel recovery sub-module 221 includes a recovery polarization component 2211 and a recovery vortex slide 2212. The restoring vortex slide 2212 is used for converting two orthogonal column vector beams to generate corresponding polarized beams, and the restoring polarization component 2211 is used for splitting the polarized beams to form two adjustable beams. Illustratively, the restoration vortex slide 2212 is a vortex slide of a corresponding order, and the restoration polarization assembly 2211 may be a polarization-dependent light splitting cube.

Still further, the channel recovering sub-module 221 may further include a total reflection mirror 2213 connected to the recovering polarization component 2211 and the optical demodulating module 230, and the two tunable light beams may enter the optical demodulating module 230 set through the total reflection mirror 2213 and the recovering polarization component 2211, respectively.

Referring to fig. 3 again, in one possible implementation of the present embodiment, the optical demodulation module 230 includes an optical demodulation sub-module 231 and an optical decoupling sub-module 232.

The optical demodulation sub-module 231 is connected to the channel recovery sub-module 221, and the optical demodulation sub-module 231 demodulates the tunable optical beams and converts the tunable optical beams transmitted in the spatial light field into corresponding decoupled signals. Illustratively, the optical demodulation sub-module 231 may be a focal length adjustable collimator.

The optical decoupling sub-module 232 is connected to the optical demodulating sub-module 231 and the plurality of receivers 240, respectively, and decouples the decoupling signal to obtain signals of the plurality of corresponding signal sources 120. Illustratively, the optical decoupling sub-module 232 may be a demultiplexer.

In this embodiment, according to different polarization distributions of the column vector light field, the polarization recovery component 2211 with different polarization angles is arranged, and the optical demodulation sub-module 231 is set to select information in the received vector light beam, filter other information, and complete loading demodulation of signals.

Referring to fig. 2 and 3 again, in one possible implementation of the present embodiment, the signal receiving system 200 further includes a beam quality analysis module 250, a state monitoring module 260, a feedback modulation module 270, and a second signal sending module 280, and the signal receiving system 100 further includes a second signal receiving module 170 and a data extraction module 180.

The beam quality analysis module 250 is connected to the first beam splitting sub-module 211 and the feedback modulation module 270, respectively, and is configured to perform quality analysis on the received laser beam, so as to obtain a first data signal carrying a quality analysis result. Specifically, the beam quality analysis module 250 and the first beam splitting sub-module 211 further include two total reflection mirrors 251, where the two total reflection mirrors 251 split the received laser beam into two 1/2 laser beams, where one 1/2 laser beam is used for quality analysis to obtain the atmospheric loss of information in the process of spatial free channel transmission, and the other 1/2 laser beam is used as the channel stable field of the feedback beam. In addition, a filter 252 is further included between the beam quality analysis module 250 and the total reflection mirror 251, for absorbing the energy of the pulsed laser beam. The filter 252 may be an 800nm filter for absorbing energy of a pulsed laser beam in the 800 band, for example.

In some possible embodiments, the spatial laser communication system 10 provided by the present application may also be applied to detect complex atmospheric environments.

The state monitoring module 260 is respectively connected to the plurality of receivers 240 and the feedback modulation module 270, and is configured to detect signals received by the plurality of signal sources 120 by the receivers 240, so as to obtain a second data signal.

The feedback modulation module 270 modulates the first data signal and the second data signal, and combines the received laser beam with the modulated first data signal and the modulated second data signal to obtain a feedback beam.

The second signal transmitting module 280 is connected to the feedback modulating module 270, and is configured to transmit the feedback beam to the second signal receiving module.

The data extraction module 180 is connected to the second signal receiving module 170 and the control module 160, and is configured to extract information in the feedback beam received by the second signal receiving module 170, and send the extracted information to the control module 160.

In this embodiment, the second signal sending module 280 and the second signal receiving module 170 are used for transmitting downlink data.

Further, the feedback modulation module 270 further includes a feedback modulation sub-module 271, a feedback swirl slide 272, and a feedback combining component 273.

The feedback modulation sub-module 271 is configured to convert the first data signal and the second data signal into data beams transmitted on a spatial light field, the feedback vortex slide 272 is configured to convert the data beams into feedback column vector beams, and the feedback beam combining component 273 is configured to combine the feedback column vector beams with the received laser beams to obtain feedback beams.

It should be noted that, the feedback modulation sub-module 271 and the beam quality analysis module 250 provide a voltage signal via a driving motor, and the feedback modulation sub-module 271 may modulate the first data signal and the second data signal according to the voltage signal provided by the driving motor.

The data extraction module 180 performs feedback information in the feedback beam received by the second signal receiving module 170, and sends the extracted feedback information to the control module 160, where the control module 160 performs self-adjustment on the excitation light module 110 and the optical modulation sub-module 132 according to the feedback information.

In summary, an embodiment of the present application provides a spatial laser communication system, which includes a signal receiving system and a signal receiving system, where the signal receiving system includes an excitation light module, a plurality of signal sources, an optical modulation module, a channel expansion module, and a first signal transmitting module, and the signal receiving system includes a first receiving module, a channel recovery module, an optical demodulation module, and a plurality of receivers. In the structure, the optical modulation module and the channel capacity expansion module are matched, namely multiplexing of the modulated light beams with multiple polarization states and a plurality of vector light fields is utilized, the polarized light fields are used as information carriers, the vector light fields are used as transmission modes, the number of parallel communication channels in the space is increased to improve the capacity of communication information, and capacity expansion is achieved. Meanwhile, by adopting the high-energy pulse laser beam, a high-transmission channel can be opened for the information light field in cloud and fog weather by utilizing the space transmission characteristic (hairline effect), so that the low-loss transmission of the information light field in cloud and fog conditions is ensured.

The above description is only of the preferred embodiments of the present application and is not intended to limit the present application, but various modifications and variations can be made to the present application by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the protection scope of the present application.

Claims

1. A space laser communication system, characterized in that the system comprises a signal transmitting system and a signal receiving system;

the excitation light module is used for generating a laser beam;

2. The spatial laser communication system of claim 1 wherein the multiplexed modulated light beam is configured as a plurality of modulated light beam sets, the channel expansion module comprising a channel expansion sub-module corresponding to the plurality of modulated light beam sets;

3. The spatial laser communication system of claim 2, wherein the channel expansion submodule comprises a polarizing component and a swirl slide;

4. The spatial laser communication system of claim 3 wherein the modulated beam set comprises a first modulated beam and a second modulated beam of different polarization states, the channel expansion Rong Zi module further comprising a total reflection assembly;

5. The spatial laser communication system of claim 4 wherein the channel expansion module further comprises a first beam combining sub-module coupled to each of the channel expansion sub-modules, wherein the first beam combining sub-module is configured to combine the column vector beams generated by the plurality of channel expansion sub-modules into the transmit vector beam.

6. The spatial laser communication system of claim 5 wherein the signal transmission system further comprises a control module, the optical modulation module comprising an optical coupling sub-module and an optical modulation sub-module;

7. The spatial laser communication system of claim 6 wherein the first signal transmission module comprises a second beam combining sub-module and the first receiving module comprises a first beam splitting sub-module;

8. The spatial laser communication system of claim 7, wherein the channel recovery module comprises a second beam splitting module and a plurality of channel recovery sub-modules;

9. The spatial laser communication system of claim 8, wherein the channel recovery submodule includes a recovery polarization component and a recovery vortex slide;

10. The spatial laser communication system of claim 9, wherein the optical demodulation module comprises an optical decoupling sub-module and an optical demodulation sub-module;

11. The spatial laser communication system of claim 10 wherein the signal receiving system further comprises a beam quality analysis module, a status monitoring module, a feedback modulation module, and a second signal transmitting module, the signal transmitting system further comprising a second signal receiving module and a data extraction module;

12. The spatial laser communication system of claim 11, wherein the feedback modulation module further comprises a feedback modulation sub-module, a feedback vortex slide, and a feedback beam combining assembly;