An encoded optical communication method and system

Abstract

The application relates to an encoding light communication method and system, and belongs to the technical field of light communication, wherein the method comprises the following steps: superimposing and combining spin rotating light beams with different phase parameters and position parameters according to to-be-transmitted information to obtain a phase hologram of a spin rotating light beam array; obtaining an intensity distribution image of the spin rotating light beam array, wherein the intensity distribution image is obtained by modulating Gaussian light by loading the phase hologram into a spatial light modulator; and decoding the intensity distribution image to obtain decoded information. The phase parameters and the position parameters of each light beam in the spin rotating light beam array are regulated, so that the channel capacity of communication is improved by using limited parameters.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of optical communication technology, and in particular to an encoding optical communication method and system. BACKGROUND

[0002] With the development of information technology, the rapid explosion of technologies such as the Internet of Things, big data, and AI, people's demand for data has increased dramatically, and optical communication technology is a communication method that uses light waves as a transmission medium. Light waves and radio waves belong to electromagnetic waves, but light waves have a higher frequency and shorter wavelength than radio waves. Optical communication has become an important research direction in the field of modern communication because of its advantages such as wide transmission bandwidth, large communication capacity, and strong anti-electromagnetic interference capability.

[0003] Encoding technology in optical communication refers to the process of converting digital signals into optical signals suitable for transmission in optical fibers. It enhances the reliability of signals by introducing redundancy into the signals and converts digital signals into optical signals using modulation techniques. In the prior art, common encoding techniques include modulation encoding, which is the process of converting digital signals into analog optical signals. It uses different modulation methods to introduce different characteristics into optical signals to achieve high-speed and large-capacity data transmission.

[0004] However, the current encoding scheme in the field of optical communication still has the problem of low data capacity, which cannot meet the increasing demand for data. SUMMARY

[0005] Therefore, it is necessary to provide an encoding optical communication method and system to solve the problem of low data capacity in the prior art, which cannot meet the increasing demand for data.

[0006] To solve the above problems, the present application provides an encoding optical communication method, comprising:

[0007] Superimposing and combining spin rotating beams with different phase parameters and position parameters according to the information to be transmitted to obtain a phase hologram of a spin rotating beam array;

[0008] Obtaining an intensity distribution image of the spin rotating beam array, which is obtained by modulating Gaussian light by loading the phase hologram into a spatial light modulator;

[0009] Decoding the intensity distribution image to obtain decoded information.

[0010] In some possible implementation manners, superimposing and combining spin rotating beams with different phase parameters and position parameters according to the information to be transmitted to obtain a phase hologram of a spin rotating beam array, comprising:

[0011] By combining and superimposing spin beams with different phase parameters as sub-phases, a composite phase of the spin beam array is obtained. By adjusting the grating parameters corresponding to different spin beams, the position parameters of each spin beam in the spin beam array are changed, and a phase hologram of the spin beam array is synthesized.

[0012] In some possible implementations, the phase parameters include the number and rotation angle.

[0013] In some possible implementations, the functional expression of the self-rotating beam phase in polar coordinates is:

[0014]

[0015] In the formula, express phase, Represents a polar coordinate system. Represents a constant. yes The normalization factor, Indicates the radial offset factor. Indicates the number of self-rotating beams. This indicates the rotation angle of the spinning beam. Represents the normalized radius The coefficient.

[0016] In some possible implementations, the position parameters include the lateral and longitudinal positions of the spinning beam in the spinning beam array.

[0017] In some possible implementations, the mathematical expression for the phase hologram is:

[0018]

[0019] In the formula, Indicates the phase of a self-rotating beam array. This represents the complex parameter function for calculating complex amplitude. Indicates the first in the self-rotating beam array The phase of a self-rotating beam, This represents the total number of rotating beams superimposed in the rotating beam array. Indicates the first in the self-rotating beam array Weighting coefficients for each self-rotating beam. It is a constant. and They are and The phase shift coefficient in the direction is used to adjust the first... The lateral and longitudinal positions of the rotating beams in the rotating beam array.

[0020] In some possible implementation manners, the loading of the phase hologram into the spatial light modulator to modulate the Gaussian light comprises:

[0021] The phase hologram is loaded into the spatial light modulator in sequence, and a linearly polarized Gaussian light is used to irradiate the spatial light modulator, and the emergent light generates an intensity distribution of a self-rotating beam array at a focal plane after passing through an imaging lens, and the intensity distribution of the self-rotating beam array is captured by a CCD camera to obtain an intensity distribution image of the self-rotating beam array.

[0022] In some possible implementation manners, the intensity distribution image is decoded to obtain decoding information, comprising:

[0023] The two-dimensional normalized cross-correlation coefficient is calculated for the intensity distribution image and a standard image, and a three-dimensional coordinate at a maximum value of the two-dimensional normalized cross-correlation coefficient is taken as a corresponding decoding value to obtain the decoding information.

[0024] In some possible implementation manners, a mathematical expression of the two-dimensional normalized cross-correlation coefficient is as follows:

[0025]

[0026] In the formula, I(x,y) represents the two-dimensional normalized cross-correlation coefficient, I(x,y) represents the intensity distribution image, I(x,y) represents the standard image, and I(x,y) represents an average value of the standard image. In the formula, I(x,y) represents the two-dimensional normalized cross-correlation coefficient, I(x,y) represents the intensity distribution image, I(x,y) represents the standard image, and I(x,y) represents an average value of the standard image.

[0027] The application further provides an encoding optical communication system, comprising:

[0028] An encoding module is configured to superimpose and combine self-rotating beams with different phase parameters and position parameters according to to-be-transmitted information to obtain a phase hologram of a self-rotating beam array.

[0029] A modulation module is configured to obtain an intensity distribution image of the self-rotating beam array, wherein the intensity distribution image is obtained by loading the phase hologram into a spatial light modulator to modulate Gaussian light.

[0030] A decoding module is configured to decode the intensity distribution image to obtain decoding information.

[0031] ​​​​​The beneficial effects of the present application are: the encoding optical communication method provided by the present application superimposes and combines spin rotating light beams with different phase parameters and position parameters to realize a spin rotating light beam array, by regulating the phase parameters and position parameters of each light beam in the spin rotating light beam array, the channel capacity of communication is improved using limited parameters, the decoding accuracy is enhanced, and the reliability of the optical communication system is improved. BRIEF DESCRIPTION OF DRAWINGS

[0032] Figure 1 An embodiment flow diagram of the encoding optical communication method provided by the present application is provided.

[0033] Figure 2 An intensity distribution pattern diagram of the spin rotating light beam proposed by the present application is provided.

[0034] Figure 3 A phase hologram diagram proposed by the present application is provided.

[0035] Figure 4 An embodiment structure diagram of the encoding optical communication system provided by the present application is provided.

[0036] Figure 5 A modulation device diagram proposed by the present application is provided.

[0037] Figure 6 A three-dimensional matrix data diagram proposed by the present application is provided.

[0038] Figure 7 An embodiment structure diagram of the encoding optical communication system provided by the present application is provided.

[0039] Figure 5 Marked in the middle: 51-laser, 52-polarizer, 53-first lens, 54-second lens, 55-aperture stop, 56-space light modulator, 57-third lens, 58-CCD camera. DETAILED DESCRIPTION

[0040] The technical solutions in the embodiments of the present application will be described clearly and completely below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0041] It should be understood that the schematic drawings are not drawn to scale. The flowcharts used in the present application show the operations implemented according to some embodiments of the present application. It should be understood that the operations of the flowcharts can not be implemented in sequence, the steps without logical context relationship can be reversed in sequence or implemented simultaneously. In addition, one or more other operations can be added to the flowcharts or one or more operations can be removed from the flowcharts under the guidance of the content of the present application by those skilled in the art. Some block diagrams shown in the drawings are functional entities, which do not necessarily correspond to physically or logically independent entities. These functional entities can be implemented in the form of software, or in one or more hardware modules or integrated circuits, or in different network and / or processor systems and / or microcontroller systems.

[0042] The terms "first", "second", and the like in the embodiments of the present application are only used for the purpose of description and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features. Therefore, the technical features defined with "first", "second" can explicitly or implicitly include at least one of the features. The association relationship of the associated objects described by "and / or" indicates that there can be three relationships, for example: A and / or B, which can represent the following three cases: A exists alone, A and B exist together, and B exists alone.

[0043] In this document, the term "embodiment" means that the specific features, structures or properties described in connection with the embodiment can be included in at least one embodiment of the present application. The appearance of this phrase in various places in the specification does not necessarily mean the same embodiment, nor is it independent or alternative to other embodiments. Those skilled in the art explicitly and implicitly understand that the embodiments described herein can be combined with other embodiments.

[0044] The present application provides an encoding optical communication method, which is described below respectively.

[0045] Figure 1 An embodiment flowchart of the encoding optical communication method provided by the present application is shown as follows, Figure 1 The encoding optical communication method comprises:

[0046] S101, superimposing and combining spin rotating light beams with different phase parameters and position parameters according to the information to be transmitted, to obtain a phase hologram of a spin rotating light beam array;

[0047] It should be noted that the vortex beam was discovered by Allen et al. in 1992, and has been widely used in free space optical communication field due to its theoretically unlimited orbital angular momentum. In addition, other structured beams with special properties such as self-recovery, self-bending, self-rotation, etc. have also been proven to have better anti-interference ability in optical communication field. The recently discovered self-rotating beam not only has similar orbital angular momentum to the vortex beam, but also has self-recovery and self-rotation characteristics, all of which indicate the possibility of the beam being applied to optical communication.

[0048] S102, an intensity distribution image of the self-rotating beam array is obtained by modulating the Gaussian light by loading the phase hologram into the spatial light modulator;

[0049] S103, the intensity distribution image is decoded to obtain decoding information.

[0050] Compared with the prior art, the encoding optical communication method of the present application superimposes and combines self-rotating beams with different phase parameters and position parameters to realize a self-rotating beam array. By adjusting the phase parameters and position parameters of each beam in the self-rotating beam array, the channel capacity of the communication is improved using limited parameters, the decoding accuracy is enhanced, and the reliability of the optical communication system is improved.

[0051] In some embodiments, the phase parameter includes the number and the rotation angle, and the function expression of the corresponding self-rotating beam phase in the polar coordinate system is:

[0052]

[0053] In the formula, represents the phase of the self-rotating beam, represents the polar coordinate system, represents a constant, is a normalization factor of , represents a radial offset factor, represents the number of self-rotating beams, represents the rotation angle of the self-rotating beam, represents the coefficient of the normalized radius .

[0054] In the example of the present application, it is set that , , , as shown in Figure 2 , , The intensity distribution pattern of the self-rotating beam is shown from -4 to 4.

[0055] In some embodiments, step S101 specifically includes: converting different phase parameters The self-rotating beams are combined and superimposed as sub-phases to obtain the composite phase of the self-rotating beam array. By adjusting the grating parameters corresponding to different self-rotating beams, the position parameters of each self-rotating beam in the array are changed, generating a composite phase hologram. The mathematical expression for the phase hologram is:

[0056]

[0057] In the formula, Indicates the phase of a self-rotating beam array. This represents the complex parameter function for calculating complex amplitude. This represents the total number of rotating beams superimposed in the rotating beam array, and is a positive integer. Indicates the first in the self-rotating beam array The phase of a self-rotating beam, Indicates the first in the self-rotating beam array The weighting coefficient of the th self-rotating beam in the self-rotating beam array The number of self-rotating beams and the rotation angle are respectively represented by... and express, A constant (in the example of this application) ), and They are and The phase shift coefficient in the direction is used to adjust the first phase in the self-rotating beam array. The lateral and longitudinal positions of a self-rotating beam in the beam array.

[0058] In this application example, with , , , , , , , , Taking the combination of the phases of four rotating beams as an example, the phase holographic pattern of the rotating beam array is obtained, such as... Figure 3 As shown.

[0059] In this application, a self-spinning beam is used for data simulation to observe changes in light intensity, determine the encoding format, and adjust different parameters. and This yields a basic beam coding table of 64 beams; such as Figure 4 As shown in section a, the numbers in the upper left and lower corners of each small square in section a represent the parameters of the self-spinning beam. and The red number in the upper right corner is the corresponding decimal base (0-63, 6-bit binary number).

[0060] By adjusting the position of each spin beam in the spin beam array, the position is encoded; as shown in part b of Figure 4 , the space is divided into four regions (regions 1-4), and the position information in each region can be encoded as a 2-bit binary number. "0" represents close to the center ( ), and "1" represents far from the center ( ).

[0061] According to the above process, a spin beam array can be obtained, as shown in part c of Figure 4 , the (position-parameter) information corresponding to the spin beam in each region is (10-101111) B , (10-110100) B , (11-111000) B and (00-000000) B from region 1 to region 4; in order, the designed encoding sequence structure can be obtained as shown in part d of Figure 4 , in addition, Figure 4 the background color of part d of Figure 4 and the color of the cross mark in part c of Figure 4 are consistent with the color of the corresponding region in part b of

[0062] The spin beam array can encode 32-bit binary numbers, and in each region, the spin beam can encode 8-bit binary numbers, including 2-bit position information and 6-bit beam information. The proposed encoding method can encode 32-bit binary numbers on a single image in a single refresh time. Compared with the current encoding scheme in the field of optical communication, the data capacity is larger.

[0063] In some embodiments, step S102 specifically comprises: loading the phase hologram into the spatial light modulator in turn, and using a linearly polarized Gaussian light to illuminate the spatial light modulator, the exit light produces an intensity distribution of a spin beam array at the focal plane after passing through the imaging lens, and the intensity distribution image of the spin beam array is obtained by capturing via a CCD camera.

[0064] Specifically, the modulation device is as shown in Figure 5As shown, the laser 51, the polarizer 52, the first lens 53, the second lens 54, the aperture diaphragm 55 and the spatial light modulator 56 are sequentially arranged at the transmitting end. The Gaussian beam generated by the laser 51 becomes the Gaussian light with single polarization direction after passing through the polarizer 52. Then, the Gaussian light is expanded and collimated after passing through the first lens 53 and the second lens 54. The Gaussian light with determined beam waist radius is obtained after further passing through the aperture diaphragm 55. The Gaussian light is irradiated on the spatial light modulator 56 loaded with the phase hologram, so that the digital information to be transmitted is encoded into the array of self-rotating beams with different phases by the encoding module. At the receiving end, the third lens 57 and the CCD camera 58 are arranged. The array of self-rotating beams at the focal plane is obtained by focusing through the third lens 57, and the intensity distribution diagram is captured by the CCD camera 58.

[0065] wherein it is assumed that a linearly polarized Gaussian light is incident on the spatial light modulator, and the expression before incidence is wherein, represents the polar coordinate system, represents the amplitude, represents the beam waist radius of the Gaussian beam.

[0066] At the initial plane (propagation distance ), the expression of the vortex beam carrying the phase of the self-rotating beam is:

[0067]

[0068] wherein, represents the polar coordinate system, represents the amplitude, represents the topological charge, represents the initial radius of the Gaussian beam, represents the phase of the array of self-rotating beams.

[0069] By applying the paraxial approximation, the field in the Fraunhofer diffraction zone can be calculated by the two-dimensional fast Fourier transform of the initial field: wherein, represents the Fourier transform, and the intensity of the beam is represented as .

[0070] In some embodiments, the method adopted in the step S103 for decoding is to calculate the two-dimensional normalized cross-correlation coefficient of the intensity distribution image and the standard image. The three-dimensional coordinates at the maximum value correspond to the decoded value. The mathematical expression of the two-dimensional normalized cross-correlation coefficient is:

[0071]

[0072] wherein, represents the two-dimensional normalized cross-correlation coefficient, Represents the intensity distribution image. Represents a standard image. This represents the average value of the standard image. express The average value of the region within the standard image.

[0073] In this embodiment, for Figure 4 The intensity distribution pattern of the rotating beam array in the example of section c is decoded, and the three-dimensional matrix data is synthesized by the two-dimensional normalized cross-correlation arrays calculated from the basic 64 rotating beam intensity patterns, as shown in the figure. Figure 6 As shown in part a, to facilitate observation of positional information, it is also along... z The axis was calculated to display the maximum intensity projection. Figure 6 Part b; from Figure 6 As can be seen from this, the values ​​obtained by decoding are in the order of region 1 to region 4 as follows: (10) B -47、(10) B -52、(11) B -56 and (00) B -00, converted to binary, is (10-101111). B (10-110100) B (11-111000) B and (00-000000) B It is consistent with the encoded value.

[0074] To better implement the coded optical communication method in the embodiments of this application, based on the coded optical communication method, correspondingly, such as... Figure 7 As shown in the figure, this application embodiment also provides an coded optical communication system 700, including:

[0075] The encoding module 701 is used to superimpose and combine self-rotating beams with different phase parameters and position parameters according to the information to be transmitted, so as to obtain a phase hologram of the self-rotating beam array.

[0076] The modulation module 702 is used to acquire the intensity distribution image of the self-rotating beam array. The intensity distribution image is obtained by modulating Gaussian light by loading a phase hologram into a spatial light modulator.

[0077] The decoding module 703 is used to decode the intensity distribution image to obtain decoded information.

[0078] The coded optical communication system 700 provided in the above embodiments can implement the technical solutions described in the above coded optical communication method embodiments. The specific implementation principles of each unit can be found in the corresponding content in the above coded optical communication method embodiments, and will not be repeated here.

[0079] Those skilled in the art can understand that all or part of the processes of the above-mentioned embodiment methods can be completed by instructing the relevant hardware by a computer program, and the above-mentioned program can be stored in a computer readable storage medium. The computer readable storage medium is a disk, an optical disk, a read-only memory or a random access memory, etc.

[0080] The above describes in detail the method of encoding optical communication provided by the present application. The principles and implementation modes of the present application are described by applying specific examples. The above description of the embodiments is only used to help understand the method of the present application and its core idea. Meanwhile, for those skilled in the art, according to the idea of the present application, the specific implementation modes and application ranges can be changed. In summary, the content of the specification should not be understood as a limitation of the present application.

[0081] The above is only the preferred specific implementation mode of the present application, but the protection scope of the present application is not limited to this. Any change or replacement that can be easily thought of by those skilled in the art within the technical range disclosed by the present application should be covered in the protection scope of the present application.

Claims

1. An encoding optical communication method characterized by, The application relates to a method for transmitting information by using a self-rotating light beam array, and belongs to the field of information transmission. The phase hologram of the self-rotating light beam array is obtained by superimposing and combining self-rotating light beams with different phase parameters and position parameters according to the information to be transmitted, wherein the function expression of the phase of the self-rotating light beam in a polar coordinate system is: wherein represents the phase of the spin beam, represents a polar coordinate system, represents a constant, is a normalization factor, represents a radial offset factor, represents the number of spin beams, represents the rotation angle of the spin beam, represents a coefficient of the normalized radius . An intensity distribution image of the self-rotating light beam array is obtained by loading the phase hologram into a spatial light modulator to modulate Gaussian light; wherein a laser, a polarizer, a first lens, a second lens, an aperture diaphragm and the spatial light modulator are sequentially arranged at an emitting end, Gaussian light generated by the laser passes through the polarizer to obtain Gaussian light with a single polarization direction, then passes through the first lens and the second lens to expand and collimate the Gaussian light beam, further passes through the aperture diaphragm to obtain a Gaussian light beam with a determined waist radius, and the Gaussian light beam irradiates the spatial light modulator loaded with the phase hologram, so that the digital information to be transmitted is encoded into the self-rotating light beam array with different phases by the encoding module; at a receiving end, a third lens and a CCD camera are arranged, the self-rotating light beam array intensity distribution at a focal plane is obtained through focusing of the third lens, and the intensity distribution image of the self-rotating light beam array is captured by the CCD camera; The intensity distribution image is decoded to obtain decoding information.

2. The coded light communication method of claim 1, wherein, The phase hologram of the self-rotating light beam array is obtained by superimposing and combining self-rotating light beams with different phase parameters and position parameters according to the information to be transmitted, including: The self-rotating light beams with different phase parameters are combined and superimposed as sub-phases to obtain a composite phase of the self-rotating light beam array, the position parameters of the self-rotating light beams in the self-rotating light beam array are changed by adjusting grating parameters corresponding to the self-rotating light beams, and the phase hologram of the self-rotating light beam array is obtained by synthesis.

3. The coded light communication method of claim 1, wherein, The phase parameters include the number and the rotation angle.

4. The coded light communication method of claim 1, wherein, The position parameters include the transverse and longitudinal positions of the self-rotating light beams in the self-rotating light beam array.

5. The coded light communication method of claim 1, wherein, The mathematical expression of the phase hologram is: In the formula, Indicates the phase of a self-rotating beam array. This represents the complex parameter function for calculating complex amplitude. Indicates the first in the self-rotating beam array The phase of a self-rotating beam, This represents the total number of rotating beams superimposed in the rotating beam array. Indicates the first in the self-rotating beam array Weighting coefficients for each self-rotating beam. It is a constant. and They are and The phase shift coefficient in the direction is used to adjust the first... The lateral and longitudinal positions of the rotating beams in the rotating beam array.

6. The coded light communication method of claim 1, wherein, The intensity distribution image is decoded to obtain decoding information, including: The three-dimensional coordinates at the maximum value of the two-dimensional normalized cross-correlation coefficient are taken as the corresponding decoding value to obtain the decoding information.

7. The coded light communication method of claim 6, wherein, The mathematical expression for calculating the two-dimensional normalized cross-correlation coefficient is: wherein denotes a two-dimensional normalized cross-correlation coefficient, denotes an intensity distribution image, denotes a standard image, denotes an average value of the standard image, denotes an average value within a region in the standard image.

8. An encoded optical communication system, characterized by The application relates to a method for transmitting information by using a self-rotating light beam array, and belongs to the field of information transmission. The encoding module is used for obtaining the phase hologram of the self-rotating light beam array by superimposing and combining self-rotating light beams with different phase parameters and position parameters according to the information to be transmitted, wherein the function expression of the phase of the self-rotating light beam in a polar coordinate system is: wherein represents the phase of the spin beam, represents a polar coordinate system, represents a constant, is a normalization factor of represents a radial offset factor, represents the number of spin beams, represents the rotation angle of the spin beam, represents a coefficient of the normalized radius . The modulation module is used for acquiring an intensity distribution image of the self-rotating beam array, and the intensity distribution image is obtained by modulating the Gaussian light by loading the phase hologram into a spatial light modulator; wherein, a laser, a polarizer, a first lens, a second lens, an aperture diaphragm and the spatial light modulator are sequentially arranged at the transmitting end, the Gaussian light beam generated by the laser is single-polarized Gaussian light after passing through the polarizer, then the Gaussian light beam is expanded and collimated after passing through the first lens and the second lens, and further passes through the aperture diaphragm to obtain a Gaussian light beam with a determined waist radius, the Gaussian light beam is irradiated onto the spatial light modulator loaded with the phase hologram, so that the digital information to be transmitted is encoded into the self-rotating beam array with different phases by the encoding module; at the receiving end, a third lens and a CCD camera are arranged, the self-rotating beam array intensity distribution at the focal plane is obtained through focusing of the third lens, and then the intensity distribution image of the self-rotating beam array is captured by the CCD camera; The decoding module is used for decoding the intensity distribution image to obtain decoded information.

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