Wireless optical communication method and device based on optical intelligent reflective surface

Abstract

The present application relates to a wireless optical communication method and device based on an optical intelligent reflection surface, wherein the method includes: optimizing optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters for a preset target; performing transmitter precoding by setting a precoding matrix to change the signal distribution at the transmitting end; changing the non-line-of-sight path signal of wireless optical communication by setting and regulating optical intelligent reflection surface parameters; and performing receiver signal detection by setting a signal detection matrix. The present application effectively improves the spatial multiplexing gain of wireless optical communication, reduces the mean square error and bit error rate of the wireless optical communication system, and alleviates the problems of poor communication performance of the wireless optical communication system caused by obstacles.

Description

Technical Field

[0001] The present application relates to the field of intelligent reflective communication technology, and in particular to a wireless optical communication method and device based on an optical intelligent reflective surface. Background Art

[0002] In order to cope with the approximately 50 exabytes of data traffic generated per month by the fifth-generation (5G) mobile communication systems and beyond, wireless communication technologies that have made significant progress in many aspects can provide higher spectrum and energy efficiency, more reliable signal transmission, and lower transmission latency.

[0003] Unlike other wireless communication technologies such as millimeter wave communication and terahertz communication, visible light communication (VLC) can modulate the signal on the amplitude of electromagnetic waves in the wavelength range of 480 nanometers to 750 nanometers through intensity modulation / direct detection non-coherent modulation. Due to the unlicensed advantage of the working frequency band, VLC can use the rich spectrum resources of about 400 terahertz for free, greatly improving the system capacity. At the same time, VLC uses low-power transceivers including light emitting diodes (LEDs) and photodetectors (PDs), which are far superior to other radio frequency (RF) communications in terms of energy efficiency. Therefore, VLC is also a green technology; in addition, VLC has natural advantages in ultra-dense frequency reuse, ubiquity and physical layer security. Therefore, the development of VLC technology has attracted great attention from academia and industry, including the VLC Alliance, IEEE 802.15.7 Group and Home Gigabit Access (OMEGA).

[0004] However, the development of VLC technology also faces severe challenges, especially in Multiple-Input Multiple-Output (MIMO) VLC systems. Specifically, the intensity modulation / direct detection scheme imposes a non-negative real-valued constraint on the signal amplitude; the channel response usually follows the Lambertian model, that is, the received optical signal strength is highly dependent on the geometric position of the transceiver and the set parameters it has. Considering the typical scenario where PDs are close to each other, the spatial eigenvectors of each LED at the multi-antenna receiver are almost in the same direction, resulting in poor multiplexing gain and diversity gain of MIMO VLC compared to RF MIMO.

[0005] At present, related technologies can improve MIMO VLC performance by designing the shape of the receiver, such as angle diversity receivers, PDs with narrow field of view (FoV), imaging receivers, etc. On the other hand, it can also be achieved through signal processing technologies such as power allocation and transmitter precoding.

[0006] In recent years, some related technologies can also use smart metasurfaces to artificially intervene in non-line-of-sight path signals. Smart metasurfaces are two-dimensional planes composed of periodic artificial atoms. Electromagnetic waves hitting them can generate controllable induced current patterns and achieve signal orientation, polarization and absorption. Smart metasurfaces in optical bands can be realized by mirror arrays or optical reflective materials controlled by micro-electromechanical systems. There have been related studies on the reflection channel response characteristics of optical smart reflective surfaces and the deployment of optical smart reflective surfaces in receivers, transmitters and wireless environments of wireless optical communications. Experimental results show the important role of optical smart reflective surfaces in improving system performance. Considering the ability of smart metasurfaces to change wireless channels, the application of optical smart reflective surfaces in VLC to improve the strong correlation of channels, increase spatial multiplexing gain, and reduce the mean square error (MSE) and bit error ratio (BER) of wireless optical communications is a potential technology. Summary of the invention

[0007] The present application provides a wireless optical communication method and device based on an optical intelligent reflective surface, which effectively reduces the mean square error and bit error rate of the wireless optical communication system, and alleviates problems such as poor communication performance of the wireless optical communication system caused by obstructions.

[0008] The first aspect of the present application provides a wireless optical communication method based on an optical intelligent reflection surface, comprising the following steps: optimizing optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters for preset targets; performing transmitter precoding by setting a precoding matrix to change the signal distribution at the transmitting end; changing the non-line-of-sight path signal of wireless optical communication by setting and regulating the optical intelligent reflection surface parameters; and performing receiver signal detection by setting a signal detection matrix.

[0009] Optionally, in one embodiment of the present application, the optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters are optimized for preset targets, including: optimization targets include but are not limited to minimizing the mean square error of the wireless optical communication system, minimizing the bit error rate, maximizing the receiver signal-to-noise ratio, maximizing the receiver energy, and maximizing the channel capacity; optimization constraints include but are not limited to non-negative real number constraints on optical signals, total transmission power constraints, and power constraints on single transmitting antennas; optimization methods include but are not limited to alternating optimization algorithms and joint optimization algorithms.

[0010] Optionally, in one embodiment of the present application, the optimization of optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters for a preset target also includes: optimizing the optical intelligent reflection surface parameters, the transmitter precoding parameters and the receiver signal detection parameters based on the channel state information of the line-of-sight path and the non-line-of-sight path and the position information of the transmitter, the optical intelligent reflection surface and the receiver.

[0011] Optionally, in one embodiment of the present application, the transmitter precoding is performed by setting a precoding matrix to change the signal distribution at the transmitting end, including: after adding a preset and DC bias to the modulated symbol sequence, baseband digital precoding is performed on the transmitted signal using a preset precoding matrix.

[0012] Optionally, in one embodiment of the present application, the non-line-of-sight path signal of the wireless optical communication is changed by setting the optical intelligent reflection surface parameters, including: the optical intelligent reflection surface parameters refer to the alignment relationship between the reflection surface unit and the transceiver antenna; based on the optimized optical intelligent reflection surface parameters, the reflection unit and the corresponding transceiver antenna are aligned by adjusting the orientation angle of the reflection unit or controlling the voltage.

[0013] Optionally, in one embodiment of the present application, the aligning of the reflection unit and the corresponding transceiver antenna includes: aligning the reflection unit and the corresponding transceiver antenna using a codebook search method or a geometric calculation method based on the optimized optical intelligent reflection surface parameters.

[0014] Optionally, in one embodiment of the present application, the performing receiver signal detection by setting a signal detection matrix includes: performing baseband digital demodulation on the received signal based on the optimized receiver signal detection parameters.

[0015] The second aspect of the present application provides a wireless optical communication device based on an optical intelligent reflecting surface, including: a central control module, used to optimize the optical intelligent reflecting surface parameters, transmitter precoding parameters and receiver signal detection parameters according to preset targets; a transmitter precoding module, used to set the precoding matrix for transmitter precoding to change the signal distribution at the transmitting end; an optical intelligent reflecting surface control module, used to set the optical intelligent reflecting surface parameters to change the non-line-of-sight path signal of the wireless optical communication; and a receiver demodulation module, used to set the signal detection matrix for receiver signal detection.

[0016] Optionally, in one embodiment of the present application, the central control module includes: optimization objectives include but are not limited to minimizing the mean square error, minimizing the bit error rate, maximizing the receiver signal-to-noise ratio, maximizing the receiver energy, and maximizing the channel capacity of the wireless optical communication system; optimization constraints include but are not limited to non-negative real number constraints on optical signals, total transmission power constraints, and power constraints on single transmitting antennas; optimization methods include but are not limited to alternating optimization algorithms and joint optimization algorithms.

[0017] Optionally, in one embodiment of the present application, the central control module also includes: an optimization unit, which is used to optimize the optical intelligent reflection surface parameters, the transmitter precoding parameters and the receiver signal detection parameters based on the channel state information of the line-of-sight path and the non-line-of-sight path and the location information of the transmitter, the optical intelligent reflection surface and the receiver.

[0018] Optionally, in one embodiment of the present application, the transmitter precoding module includes: a precoding unit, which is used to perform baseband digital precoding on the transmission signal using a preset precoding matrix after adding a preset and DC bias to the modulated symbol sequence.

[0019] Optionally, in one embodiment of the present application, the optical intelligent reflective surface control module includes:

[0020] An alignment unit, used for the alignment relationship between the optical intelligent reflection surface parameters referring to the reflection surface unit and the transceiver antenna; an execution unit, used for aligning the reflection unit and the corresponding transceiver antenna by adjusting the orientation angle of the reflection unit or controlling the voltage based on the optimized optical intelligent reflection surface parameters.

[0021] Optionally, in one embodiment of the present application, the execution unit is specifically used to align the reflection unit and the corresponding transceiver antenna based on the optimized optical smart reflection surface parameters by using a codebook search method or a geometric calculation method.

[0022] Optionally, in one embodiment of the present application, the receiver demodulation module includes: a demodulation unit, configured to perform baseband digital demodulation on the received signal based on the optimized receiver signal detection parameters.

[0023] The third aspect of the present application provides an electronic device, comprising: a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the wireless optical communication method based on the optical smart reflective surface as described in the above embodiment.

[0024] The fourth aspect of the present application provides a computer-readable storage medium, which stores a computer program. When the program is executed by a processor, it implements the above-mentioned wireless optical communication method based on optical smart reflective surface.

[0025] Therefore, the embodiments of the present application have the following beneficial effects:

[0026] The embodiments of the present application can optimize the optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters for preset targets; perform transmitter precoding by setting the precoding matrix to change the signal distribution at the transmitting end; change the non-line-of-sight path signal of wireless optical communication by regulating the optical intelligent reflection surface parameters; and perform receiver signal detection by setting the signal detection matrix. Thus, the embodiments of the present application can regulate the signal of the non-line-of-sight path in wireless optical communication, and by optimizing the optical intelligent reflection surface, the precoding matrix and the signal detection matrix, effectively reduce the mean square error and bit error rate of the wireless optical communication system, reduce the impact of obstacles on wireless optical communication, increase the receiver signal-to-noise ratio, and improve the spatial multiplexing gain and system communication performance. As a result, the problem of poor communication performance of the wireless optical communication system caused by obstacles is solved.

[0027] Additional aspects and advantages of the present application will be given in part in the description below, and in part will become apparent from the description below, or will be learned through the practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The above and / or additional aspects and advantages of the present application will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

[0029] Figure 1 A flowchart of a wireless optical communication method based on an optical smart reflective surface provided according to an embodiment of the present application;

[0030] Figure 2 A signal processing block diagram provided for one embodiment of the present application;

[0031] Figure 3A schematic diagram of a multi-input multi-output wireless optical communication system model provided for one embodiment of the present application;

[0032] Figure 4 is an exemplary diagram of a wireless optical communication device based on an optical smart reflective surface according to an embodiment of the present application;

[0033] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application.

[0034] Explanation of the reference numerals: wireless optical communication device based on optical intelligent reflecting surface - 10; central control module - 100, transmitter precoding module - 200, optical intelligent reflecting surface control module - 300, receiver demodulation module - 400; memory - 501, processor - 502, communication interface - 503. DETAILED DESCRIPTION

[0035] Embodiments of the present application are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and should not be construed as limiting the present application.

[0036] The following describes the wireless optical communication method and device based on the optical intelligent reflection surface of the embodiment of the present application with reference to the accompanying drawings. In response to the problems mentioned in the above background technology, the present application provides a wireless optical communication method based on the optical intelligent reflection surface, in which the optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters are optimized according to the preset target; the precoding matrix is ​​set to perform transmitter precoding to change the signal distribution at the transmitting end; the non-line-of-sight path signal of the wireless optical communication is changed by setting the optical intelligent reflection surface parameters, and the receiver signal detection is performed by setting the signal detection matrix, so that the embodiment of the present application can regulate the signal of the non-line-of-sight path in the wireless optical communication, and optimize the optical intelligent reflection surface, the precoding matrix and the signal detection matrix. The present application effectively improves the spatial multiplexing gain of the wireless optical communication and reduces the mean square error and bit error rate of the wireless optical communication system. As a result, the problem of poor communication performance of the wireless optical communication system caused by obstacles is solved.

[0037] Specifically, Figure 1 A flowchart of a wireless optical communication method based on an optical smart reflective surface provided in an embodiment of the present application.

[0038] like Figure 1 As shown, the wireless optical communication method based on the optical smart reflective surface includes the following steps:

[0039] In step S11, optical smart reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters are optimized for preset targets.

[0040] The embodiments of the present application can first optimize the optical smart reflective surface, transmitter precoding and receiver signal detection parameters according to preset goals, thereby providing reliable data support for the implementation of wireless optical communication based on the optical smart reflective surface.

[0041] Optionally, in one embodiment of the present application, optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters are optimized for preset targets, including: optimization targets include but are not limited to minimizing the mean square error of the wireless optical communication system, minimizing the bit error rate, maximizing the receiver signal-to-noise ratio, maximizing the receiver energy, and maximizing the channel capacity; optimization constraints include but are not limited to non-negative real number constraints on optical signals, total transmission power constraints, and power constraints on single transmitting antennas; optimization methods include but are not limited to alternating optimization algorithms and joint optimization algorithms.

[0042] In an embodiment of the present application, a joint alternating optimization algorithm can be used to obtain an optical smart reflection surface matrix, a precoding matrix and a signal detection matrix according to channel state information, so as to achieve optimization of specific goals, for example, minimization of mean square error, minimization of bit error rate, maximization of receiver signal-to-noise ratio, maximization of receiver energy, maximization of channel capacity, etc. of a wireless optical communication system; in addition, the optimization constraints in the embodiments of the present application mainly include non-negative real number constraints of optical signals, total transmission power constraints, power constraints of a single transmitting antenna, etc.

[0043] It should be noted that, in the embodiments of the present application, the number of transmitters, the number of optical smart reflective surface units, and the number of receivers may be one or more.

[0044] The optimization algorithm adopted in the embodiments of the present application includes alternately optimizing the optical intelligent reflection surface matrix, the precoding matrix and the signal detection matrix, wherein each sub-process can adopt algorithms including the Lagrangian dual optimization method, obtaining a closed-form optimal solution by solving the KKT condition, a stochastic gradient descent algorithm, a genetic algorithm, simulated degradation, etc., or use an optimization algorithm that jointly optimizes the optical intelligent reflection surface matrix, the precoding matrix and the signal detection matrix to achieve optimization of a specific goal.

[0045] It should be noted that those skilled in the art can select optimization objectives, constraints and methods to achieve wireless optical communication according to actual conditions, and no specific restrictions are made here.

[0046] Optionally, in one embodiment of the present application, the optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters are optimized for a preset target, and also include: optimizing the optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters based on the channel state information of the line-of-sight path and the non-line-of-sight path and the position information of the transmitter, the optical intelligent reflection surface and the receiver.

[0047] Specifically, the embodiments of the present application implement the specific steps of optimizing a specific goal by setting an optical smart reflective surface, transmitter precoding, and receiver signal detection as follows:

[0048] 1. The central control system obtains the channel status information of the line-of-sight path and the non-line-of-sight path;

[0049] It should be noted that the embodiments of the present application can use channel estimation technology to obtain channel state information of line-of-sight paths and non-line-of-sight paths. Among them, the channel estimation technology can be based on a pilot sequence, such as a least squares estimation method, a (linear) minimum mean square error estimation method, etc., or it can be a channel estimation technology based on a time domain training sequence. Those skilled in the art can choose according to actual conditions, and no specific limitation is made here.

[0050] In addition, the channel estimation of the line-of-sight path needs to be performed with the optical smart reflective surface turned off; the channel estimation of the non-line-of-sight path can be performed by turning on each unit of the metasurface in turn to estimate the channel response of the reflection path.

[0051] 2. The central control system obtains the location information of the transmitter, the optical intelligent reflective surface and the receiver;

[0052] It should be noted that in the embodiments of the present application, the location information of the transmitter and the optical intelligent reflective surface is system a priori information and is fixed. During the specific implementation process, technicians can use indoor wireless positioning technology to estimate the location information of the receiver, including infrared indoor positioning technology, visible light positioning technology, ultra-wideband positioning technology, etc.

[0053] 3. For a certain target, the central control system uses algorithms to optimize the optical smart reflective surface, transmitter precoding and receiver signal detection.

[0054] Figure 2 is a block diagram of wireless optical communication based on optical smart reflective surface, where N t 、N r and N s They represent the number of transmitting antennas, the number of receiving antennas and the number of independent parallel data streams respectively. The signal source bit sequence is converted into a symbol sequence through serial-to-parallel conversion and M-order pulse amplitude modulation, as shown in the following formula:

[0055]

[0056] Where I is a normalized parameter. The symbol sequence passes through the wireless optical channel H after baseband digital precoding W and DC bias r.

[0057] The receiver signal is represented as:

[0058] y=H(Wx+r)+ω,

[0059] Among them, ω is the Gaussian white noise of the receiver. Finally, after the receiver signal detection Q, the demodulated symbol is obtained:

[0060]

[0061] And according to and x to obtain the specific optimization target.

[0062] It should be noted that the embodiments of the present application can use MSE as an optimization target, and its expression is:

[0063]

[0064] in, and are the autocorrelation matrices of the transmitted signal and noise respectively. The two items in H=H1+H2 are the line-of-sight path channel matrix and the non-line-of-sight path channel matrix respectively. The optical smart reflective surface minimizes MSE by adjusting H2.

[0065] Specifically, the embodiment of the present application uses a binary correlation matrix between the transmitting antenna and each unit of the smart reflective surface. and As the optical smart reflective surface matrix. The number of rows of the correlation matrix G and F is the number of units of the smart reflective surface, and the number of columns is the number of antennas of the transmitter and receiver. When the matrix element is "1", it means that there is an association between the smart reflective surface unit and the corresponding transceiver antenna, that is, the non-line-of-sight path formed by the transmitting antenna, the smart reflective surface unit and the receiving antenna complies with the generalized Snell's law; when it is "0", it means that the smart reflective surface unit and the corresponding transceiver antenna are not aligned.

[0066] Based on the Lambertian radiation model, the embodiment of the present application defines the transmitting antenna n t , smart reflective surface unit n and receiving antenna n r The channel gain of the non-line-of-sight path is And define the transmitting antenna n t and receiving antenna n r The channel gain vector between Then the non-line-of-sight path channel gain H2 can be expressed as:

[0067]

[0068] In the embodiment of the present application, the optical smart reflective surface matrices G and F can be equivalently converted into a binary matrix

[0069]

[0070] Among them, ⊙ represents the Hadamard product, and The number of rows in V is equal to the number of units in the optical smart reflective surface, N, and the number of columns is equal to N. t N r , and the row sum is less than or equal to 1.

[0071] Furthermore, in Figure 3 In the MIMO scenario shown, the central control system in the embodiment of the present application uses an alternating optimization algorithm to optimize the optical smart reflective surface, transmitter precoding and receiver signal detection to minimize the MSE of the MIMO wireless optical communication system.

[0072] Specifically, the non-negative matrix V represents the optical smart reflective surface parameters, the matrix W represents the transmitter precoding scheme, and the matrix Q represents the receiver signal detection scheme. The linear constrained quadratic optimization problem with fixed transmitter precoding W, receiver signal detection matrix Q, and MSE of the wireless optical communication system in convex form with respect to V can be solved by using classical convex optimization algorithms including but not limited to the projected gradient algorithm and the primal-dual algorithm.

[0073] Similarly, the optimization of the transmitter precoding W and the receiver signal detection method Q can also be solved by the convex optimization algorithm. The alternating optimization algorithm can be performed by fixing other variables and optimizing a certain variable in turn. Among them, the optimal solution for the receiver signal detection method Q is proved to be a closed form:

[0074] Q (t+1) =R x (H (t+1) W (t+1) ) T (H (t+1) W (t+1) R x (H (t+1) W (t+1) ) T +R ω ) -1

[0075] Here, t represents the iteration round.

[0076] Therefore, the embodiments of the present application can obtain the optical smart reflection surface matrix, the precoding matrix and the signal detection matrix based on the estimated channel state information using the proposed joint alternating optimization algorithm, thereby achieving optimization of specific goals.

[0077] In step S12, transmitter precoding is performed by setting a precoding matrix to change the signal distribution at the transmitting end.

[0078] After achieving optimization of specific goals by setting up an optical smart reflective surface, transmitter precoding and receiver signal detection, further, the embodiments of the present application can perform transmitter precoding by setting a precoding matrix, thereby changing the signal distribution at the transmitting end.

[0079] Optionally, in one embodiment of the present application, transmitter precoding is performed by setting a precoding matrix to change the signal distribution at the transmitting end, including: after adding a preset and DC bias to the modulated symbol sequence, baseband digital precoding is performed on the transmitted signal using a preset precoding matrix.

[0080] Specifically, in an embodiment of the present application, after adding a DC offset r to the modulated symbol sequence x, the precoding matrix W can be used to perform baseband digital precoding on the transmission signal. The precoding matrix W generally satisfies the transmission signal constraints, such as the non-negative real value constraint of the optical signal, the total transmission power constraint, the power constraint of a single transmission antenna, etc.

[0081] It should be noted that, in the embodiments of the present application, the baseband digital precoding matrix W can be obtained by using classical convex optimization algorithms such as the projected gradient algorithm and the primal-dual algorithm.

[0082] In addition, during the specific implementation process, those skilled in the art may select a suitable baseband digital precoding matrix W according to actual conditions, such as using zero-forcing precoding, minimum mean square error precoding and matched filtering, so as to change the signal distribution at the transmitting end.

[0083] In step S13, the non-line-of-sight path signal of the wireless optical communication is changed by setting and regulating the optical smart reflective surface parameters.

[0084] After changing the signal distribution at the transmitting end, further, the embodiments of the present application can also change the non-line-of-sight path signal of the wireless optical communication by setting the optical intelligent reflection surface parameters, and detect the receiver signal by setting the signal detection matrix.

[0085] Optionally, in one embodiment of the present application, the non-line-of-sight path signal of the wireless optical communication is changed by setting the optical intelligent reflection surface parameters, including: the optical intelligent reflection surface parameters refer to the alignment relationship between the reflection surface unit and the transceiver antenna; based on the optimized optical intelligent reflection surface parameters, the reflection unit and the corresponding transceiver antenna are aligned by adjusting the orientation angle of the reflection unit or controlling the voltage.

[0086] Those skilled in the art should understand that the optical smart reflective surface parameters refer to the alignment relationship between the reflective surface unit and the transceiver antenna, wherein the configuration parameters of each unit of the optical smart reflective surface are determined by its physical implementation method, the mirror array based on micro-electromechanical system control can be achieved by adjusting the orientation angle of each unit, and the smart reflective surface based on optical metamaterials can be achieved by adjusting the control voltage of each unit of the reflective surface.

[0087] Specifically, the embodiments of the present application set the optical smart reflective surface parameters to change the non-line-of-sight path signal of wireless optical communication in the following specific steps:

[0088] 1. According to the optical intelligent reflective surface matrix, the alignment relationship of the reflected light path is obtained;

[0089] 2. According to the alignment relationship among the transmitting antenna, the reflecting surface unit and the receiving antenna in the reflecting light path, the parameters of each unit of the optical intelligent reflecting surface are adjusted.

[0090] Among them, the optical smart reflective surface matrix and They represent the alignment relationship between the smart reflective surface and the transmitter antenna and the receiver antenna, respectively. The number of rows of the association matrix G and F is the number of units of the smart reflective surface, and the number of columns is the number of antennas of the transmitter and the receiver, respectively. When the matrix element is "1", it means that there is an association between the smart reflective surface unit and the corresponding transceiver antenna, that is, the non-line-of-sight path formed by the transmitting antenna, the smart reflective surface unit and the receiving antenna complies with the generalized Snell's law; otherwise, it means that there is no association, that is, the smart reflective surface unit and the corresponding transceiver antenna are not aligned.

[0091] Optionally, in one embodiment of the present application, aligning the reflection unit and the corresponding transceiver antenna includes: aligning the reflection unit and the corresponding transceiver antenna using a codebook search method or a geometric calculation method based on optimized optical smart reflection surface parameters.

[0092] The configuration of the reflective surface parameters according to the defined smart reflective surface matrix depends on the alignment of the reflective light path, including the alignment of the smart reflective surface unit and the transmitter antenna, and the alignment with the receiver antenna. In the embodiment of the present application, the reflective light path alignment can be performed by the following alignment method:

[0093] (1) Codebook search method: For the selected transmitter antenna and optical smart reflection surface unit, the projection position of the non-line-of-sight path signal on the user plane can be changed by adjusting the configuration parameters of the optical smart reflection surface. In each implementation, the projection position and the configuration parameters are combined as a codeword in the codebook. In a typical indoor wireless optical communication scenario, the positions of the transmitter and the optical smart reflection surface remain fixed, so the codebook only needs to be generated once, which has a lower complexity. Furthermore, according to the alignment relationship between the smart reflection surface and the transmitter antenna and the receiver antenna, the specific configuration parameters of the unit are obtained by comparing the codebook;

[0094] It should be noted that in the codebook search method, the codebook only needs to be generated once, so it has lower complexity and can meet the dynamic requirements of the system.

[0095] (2) Geometric calculation method: When the positions of the transmitter and the optical smart reflective surface are fixed and known, the required orientation of the smart reflective surface unit can be calculated according to the generalized Snell's law.

[0096] Those skilled in the art may also provide other methods for aligning the reflected light path, which are not specifically limited here.

[0097] Therefore, the embodiments of the present application can use methods such as codebook search to align the reflected light path, thereby realizing the configuration of the optical intelligent reflective surface parameters and effectively improving the communication performance of the system.

[0098] In step S14, receiver signal detection is performed by setting a signal detection matrix.

[0099] Furthermore, the embodiments of the present application may also perform receiver signal detection by setting a signal detection matrix.

[0100] Optionally, in one embodiment of the present application, receiver signal detection is performed by setting a signal detection matrix, including: performing baseband digital demodulation on the received signal based on optimized receiver signal detection parameters.

[0101] Specifically, the received signal at the receiver in the embodiment of the present application is:

[0102] y=H(Wx+r)+ω,

[0103] After the DC part Hr of the signal is removed, the demodulated symbol sequence is obtained through the detection matrix Q Finally, the demodulated bit sequence is obtained according to the bit mapping method.

[0104] It should be noted that the detection matrix Q can be obtained through classical convex optimization algorithms such as the projected gradient algorithm and the primal-dual algorithm, and the optimal detection matrix Q can be obtained by solving the KKT condition to obtain a closed-form solution.

[0105] As another possible implementation method, the detection matrix Q may also use zero-forcing detection, minimum mean square error detection, matched filtering, etc. In addition, for non-convex situations, the embodiments of the present application may use non-convex optimization tools including continuous convex approximation for solution.

[0106] Specifically, the present application can further illustrate the wireless optical communication method based on the optical smart reflective surface through the following specific embodiments.

[0107] Embodiment 1

[0108] In a multiple-input multiple-output wireless optical communication system, such as Figure 3 As shown, the optical intelligent reflective surface is realized based on a mirror array controlled by a micro-electromechanical system. The wireless optical communication method based on the optical intelligent reflective surface in the embodiment of the present application adopts an M-order pulse amplitude modulation scheme. The specific steps have been introduced in detail above and will not be repeated here.

[0109] Embodiment 2

[0110] In a multiple-input multiple-output wireless optical communication system, such as Figure 3 As shown, N r =N s =1, the optical intelligent reflective surface is realized based on a mirror array controlled by a micro-electromechanical system. The wireless optical communication method based on the optical intelligent reflective surface in the embodiment of the present application adopts an M-order pulse position modulation scheme. The method comprises the following steps:

[0111] Step S21: maximizing the channel capacity of the communication system by setting an optical smart reflective surface, transmitter precoding and receiver signal detection;

[0112] Figure 2 Block diagram of wireless optical communication based on optical smart reflective surface, N t 、N r and N s The signal source bit sequence is converted into a symbol sequence by serial-to-parallel conversion and M-order pulse position modulation. in is a symbol set. The symbol sequence passes through the wireless optical channel H after baseband digital precoding W and DC bias r. The receiver signal is expressed as y=H(Wx+r)+ω, where ω is the Gaussian white noise of the receiver. Finally, the demodulated symbol is obtained after the receiver signal detection Q And according to and x to obtain the equivalent MIMO VLC channel capacity, which is expressed as:

[0113]

[0114] in, is the autocorrelation matrix of the noise, A i is the peak power constraint of the i-th transmitting antenna, and e is the base of the natural logarithm. The two terms in H=H1+H2 are the line-of-sight path channel matrix and the non-line-of-sight path channel matrix, respectively. The optical smart reflective surface maximizes the MIMO VLC channel capacity by regulating H2.

[0115] Specifically, the linear minimum mean square error estimation of the channel state information is first performed through the time domain training sequence. Among them, the channel estimation of the line-of-sight path is carried out when the optical intelligent reflection surface is turned off; the channel estimation of the non-line-of-sight path turns on each unit of the super surface in turn to estimate the channel response of the reflection path. Then the ultra-wideband positioning technology is used to obtain the position information of the receiver. Finally, the central control system uses an algorithm to optimize the optical intelligent reflection surface V, the transmitter precoding W and the receiver signal detection matrix Q to maximize the MIMO VLC channel capacity. Specifically, the transmitter precoding W and the receiver signal detection matrix Q are fixed, and the MIMO VLC channel capacity expression is a non-convex function with respect to V, which can be optimized using algorithms such as continuous convex approximation or particle swarm optimization; the optimization of the transmitter precoding W and the receiver signal detection matrix Q also adopts an alternating optimization algorithm, which is carried out by fixing other variables in turn and optimizing the target variable.

[0116] Step S22: performing transmitter precoding by setting a precoding matrix to change the signal distribution at the transmitting end;

[0117] After adding a DC offset r to the modulated symbol sequence x, the transmitted signal is baseband digitally precoded using the precoding matrix W. Under the constraints of the optical signal non-negative real value and the total transmit power, the baseband digital precoding matrix W uses zero-forcing precoding.

[0118] Step S23: changing the non-line-of-sight path signal of the wireless optical communication by setting the optical intelligent reflective surface parameters;

[0119] Specifically, first, the alignment relationship of the reflection light path is obtained according to the optical smart reflection surface matrices G and F. When the matrix element is "1", it means that there is an association between the smart reflection surface unit and the corresponding transceiver antenna, that is, the non-line-of-sight path composed of the transmitting antenna, the smart reflection surface unit and the receiving antenna conforms to the generalized Snell's law; otherwise, it means that there is no association. Then, the codebook search method is used to align the reflection light path, so as to realize the configuration of the optical smart reflection surface parameters. Specifically, for the selected transmitter antenna and optical smart reflection surface unit, the projection position of the non-line-of-sight path signal on the user plane can be changed by adjusting the configuration parameters of the smart reflection surface unit. In each implementation, the projection position and the configuration parameters of the unit are combined as a codeword in the codebook. In a typical indoor wireless optical communication scenario, the positions of the transmitter and the optical smart reflection surface remain fixed, so the codebook only needs to be generated once, which has low complexity. Further, according to the alignment relationship between the smart reflection surface and the transmitter antenna and the receiver antenna, the codebook is searched to obtain the specific configuration parameters of the unit.

[0120] Step S24: Perform receiver signal detection by setting a signal detection matrix.

[0121] The received signal at the receiver is y = H(Wx + r) + ω. After the DC part Hr of the signal is removed, the demodulated symbol sequence is obtained through the detection matrix Q. Finally, the demodulated bit sequence is obtained according to the bit mapping method.

[0122] Embodiment 3

[0123] In a multiple-input single-output wireless optical communication system, such as Figure 3 As shown, N r =N s =1, the optical smart reflective surface is implemented based on optical metamaterials, and the wireless optical communication method based on the optical smart reflective surface in the embodiment of the present application adopts an M-order pulse amplitude modulation scheme, and the method includes the following steps:

[0124] Step S31: maximizing the receiver signal-to-noise ratio of the communication system by setting an optical smart reflective surface, transmitter precoding and receiver signal detection;

[0125] Figure 2 Block diagram of wireless optical communication based on optical smart reflective surface, N t 、N r and N s The signal source bit sequence is converted into a symbol sequence by serial-to-parallel conversion and M-order pulse amplitude modulation. in, is a symbol set. The symbol sequence passes through the wireless optical channel H after baseband digital precoding W and DC bias r. The receiver signal is expressed as y=H(Wx+r)+ω, where ω is the Gaussian white noise of the receiver. Finally, the demodulated symbol is obtained after the receiver signal detection Q And according to The receiver signal-to-noise ratio is obtained by adding x, which is expressed as:

[0126]

[0127] in, is the autocorrelation matrix of the transmitted signal. The two items in H=H1+H2 are the line-of-sight path channel matrix and the non-line-of-sight path channel matrix respectively. The optical smart reflective surface maximizes the receiver signal-to-noise ratio by adjusting H2.

[0128] Specifically, first, the least squares estimation of the channel state information is performed by inserting a pilot sequence. Among them, the channel estimation of the line-of-sight path is performed when the optical smart reflective surface is turned off; the channel estimation of the non-line-of-sight path turns on each unit of the metasurface in turn to estimate the channel response of the reflection path. Secondly, the position information of the receiver is obtained by using visible light positioning technology. Finally, the central control system uses an algorithm to optimize the optical smart reflective surface V, the transmitter precoding W, and the receiver signal detection Q to maximize the receiver signal-to-noise ratio. Specifically, the transmitter precoding W and the receiver signal detection matrix Q are fixed, and the receiver signal-to-noise ratio is a linear constrained quadratic optimization problem in convex form with respect to V, which can be solved by the projected gradient algorithm. The continuous convex approximation optimization algorithm is used to jointly optimize the transmitter precoding W and the receiver signal detection method Q. The alternating optimization algorithm is performed by fixing other variables in turn and optimizing the target variable.

[0129] Step S32: performing transmitter precoding by setting a precoding matrix to change the signal distribution at the transmitting end;

[0130] After adding DC offset r to the modulated symbol sequence x, the transmitted signal is baseband digitally precoded using the precoding matrix W. Under the constraints of the non-negative real value of the optical signal and the power constraint of a single transmitting antenna, the baseband digital precoding matrix W adopts minimum mean square error precoding.

[0131] Step S33: changing the non-line-of-sight path signal of the wireless optical communication by setting the optical intelligent reflective surface parameters;

[0132] Specifically, first, the alignment relationship of the reflection light path is obtained according to the optical smart reflection surface matrices G and F. When the matrix element is "1", it means that there is a correlation between the smart reflection surface unit and the corresponding transceiver antenna, that is, the non-line-of-sight path composed of the transmitting antenna, the smart reflection surface unit and the receiving antenna conforms to the generalized Snell's law; otherwise, it means that there is no correlation. Secondly, the geometric calculation method is used to align the reflection light path, so as to realize the configuration of the optical smart reflection surface parameters. Specifically, for the selected transmitter antenna and optical smart reflection surface unit, in the context of the fixed and known positions of the transmitter and the optical smart reflection surface, the required orientation of the smart reflection surface unit can be calculated according to the generalized Snell's law.

[0133] Step S34: Perform receiver signal detection by setting a signal detection matrix.

[0134] The received signal at the receiver is y = H(Wx + r) + ω. After the DC part Hr of the signal is removed, the demodulated symbol sequence is obtained through the detection matrix Q. Finally, the demodulated bit sequence is obtained according to the bit mapping method. Among them, the optimal detection matrix Q can be obtained by solving the KKT condition to obtain a closed-form solution.

[0135] Embodiment 4

[0136] In a single-input single-output wireless optical communication system, such as Figure 3 As shown, N t =N r =N s =1, the optical smart reflective surface is implemented based on optical metamaterials, and the wireless optical communication method based on the optical smart reflective surface in the embodiment of the present application adopts an M-order pulse amplitude modulation scheme, and the method includes the following steps:

[0137] Step S41: maximizing the receiver energy of the communication system by setting an optical smart reflective surface, transmitter precoding and receiver signal detection;

[0138] Figure 2 Block diagram of wireless optical communication based on optical smart reflective surface, N t 、N r and N s represent the number of transmitting antennas, the number of receiving antennas, and the number of independent parallel data streams, respectively, and N t =N r =N s =1. The signal source bit sequence is converted into a symbol sequence through serial-to-parallel conversion and M-order pulse amplitude modulation. in is a symbol set. The symbol sequence passes through the wireless optical channel H after baseband digital precoding W and DC bias r. The receiver signal is expressed as y=H(Wx+r)+ω, where ω is the Gaussian white noise of the receiver. Finally, the demodulated symbol is obtained after the receiver signal detection Q And according to and x to obtain the receiver energy, which is expressed as:

[0139] Power = tr(QHWR x (QHW) T )

[0140] in is the variance of the transmitted signal. The two terms in H = H1 + H2 are the line-of-sight path channel matrix and the non-line-of-sight path channel matrix, respectively. The optical smart reflective surface maximizes the receiver energy by adjusting H2.

[0141] Specifically, the least squares estimation of the channel state information is first performed by inserting a pilot sequence. Among them, the channel estimation of the line-of-sight path is performed when the optical smart reflective surface is turned off; the channel estimation of the non-line-of-sight path turns on each unit of the metasurface in turn to estimate the channel response of the reflection path. Secondly, the visible light positioning technology is used to obtain the position information of the receiver. Finally, the optical smart reflective surfaces G and F are both constant matrices, that is, any unit of the smart reflective surface is aligned with the only transmitting antenna and receiving antenna; the central control system uses an algorithm to optimize the transmitter precoding W and the receiver signal detection Q to maximize the receiver energy. Specifically, QHW is optimized as a whole to obtain the maximum received power solution, and then the transmitter precoding W and the receiver signal detection matrix Q are alternately optimized to minimize the Fubini norm of the difference with the optimal solution. The alternating optimization algorithm is performed by fixing other variables in turn and optimizing the target variable.

[0142] Step S42: performing transmitter precoding by setting a precoding matrix to change the signal distribution at the transmitting end;

[0143] After adding DC offset r to the modulated symbol sequence x, the transmitted signal is baseband digitally precoded using the precoding matrix W. Under the constraints of non-negative real value of the optical signal, total transmit power constraint and power constraint of a single transmit antenna, the baseband digital precoding matrix W uses matched filter precoding.

[0144] Step S43, changing the non-line-of-sight path signal of the wireless optical communication by setting the optical intelligent reflective surface parameters;

[0145] Specifically, since it is a single-input single-output wireless optical communication system, the alignment relationship is unique. Therefore, a geometric calculation method is used to align the reflection light path, thereby realizing the configuration of the optical smart reflection surface parameters. Specifically, for the transmitter antenna and the optical smart reflection surface unit, under the background that the positions of the transmitter and the optical smart reflection surface are fixed and known, the required orientation of the smart reflection surface unit can be calculated according to the generalized Snell's law.

[0146] Step S44: Perform receiver signal detection by setting a signal detection matrix.

[0147] The received signal at the receiver is y = H(Wx + r) + ω. After the DC part Hr of the signal is removed, the demodulated symbol sequence is obtained through the detection matrix Q. Finally, the demodulated bit sequence is obtained according to the bit mapping method. Among them, the optimal detection matrix Q can be obtained by solving the KKT condition to obtain a closed-form solution.

[0148] According to the wireless optical communication method based on the optical intelligent reflection surface proposed in the embodiment of the present application, the optimization of specific goals is achieved by setting the optical intelligent reflection surface, transmitter precoding and receiver signal detection; the transmitter precoding is performed by setting the precoding matrix to change the signal distribution at the transmitting end; the non-line-of-sight path signal of the wireless optical communication is changed by adjusting the parameters of the optical intelligent reflection surface; and the receiver signal detection is performed by setting the signal detection matrix, so that the embodiment of the present application can adjust the signal of the non-line-of-sight path in the wireless optical communication, and by optimizing the optical intelligent reflection surface, the precoding matrix and the signal detection matrix, the mean square error and bit error rate of the wireless optical communication system are effectively reduced, the impact of obstacles on the wireless optical communication is reduced, the receiver signal-to-noise ratio is increased, and the system communication performance is improved.

[0149] Next, a wireless optical communication device based on an optical smart reflective surface according to an embodiment of the present application is described with reference to the accompanying drawings.

[0150] Figure 4 It is a block diagram of a wireless optical communication device based on an optical smart reflective surface according to an embodiment of the present application.

[0151] like Figure 4 As shown, the wireless optical communication device 10 based on the optical smart reflective surface includes: a central control module 100 , a transmitter precoding module 200 , an optical smart reflective surface control module 300 and a receiver demodulation module 400 .

[0152] The central control module 100 is used to optimize the optical intelligent reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters according to preset targets.

[0153] The transmitter precoding module 200 is used to set a precoding matrix to perform transmitter precoding to change the signal distribution at the transmitting end.

[0154] The optical intelligent reflective surface control module 300 is used to set the optical intelligent reflective surface parameters and change the non-line-of-sight path signal of the wireless optical communication.

[0155] The receiver demodulation module 400 is used to set a signal detection matrix to perform receiver signal detection.

[0156] Optionally, in one embodiment of the present application, the central control module 100 includes: optimization objectives include but are not limited to minimizing the mean square error, minimizing the bit error rate, maximizing the receiver signal-to-noise ratio, maximizing the receiver energy, and maximizing the channel capacity of the wireless optical communication system; optimization constraints include but are not limited to non-negative real number constraints on optical signals, total transmission power constraints, and power constraints on single transmitting antennas; optimization methods include but are not limited to alternating optimization algorithms and joint optimization algorithms.

[0157] Optionally, in one embodiment of the present application, the central control module 100 also includes: an optimization unit for optimizing optical intelligent reflection surface parameters, transmitter precoding parameters and receiver signal detection parameters based on channel state information of line-of-sight paths and non-line-of-sight paths and location information of the transmitter, the optical intelligent reflection surface and the receiver.

[0158] Optionally, in one embodiment of the present application, the transmitter precoding module 200 includes: a precoding unit, which is used to perform baseband digital precoding on the transmission signal using a preset precoding matrix after adding a preset and DC bias to the modulated symbol sequence.

[0159] Optionally, in one embodiment of the present application, the optical intelligent reflective surface control module 300 includes: an alignment unit and an execution unit.

[0160] The alignment unit, used for the optical smart reflection surface parameter, refers to the alignment relationship between the reflection surface unit and the transceiver antenna.

[0161] The execution unit is used to align the reflection unit with the corresponding transceiver antenna by adjusting the orientation angle of the reflection unit or controlling the voltage based on the optimized optical intelligent reflection surface parameters.

[0162] Optionally, in one embodiment of the present application, the execution unit is specifically configured to align the reflection unit and the corresponding transceiver antenna by using a codebook search method or a geometric calculation method based on the optimized optical smart reflection surface parameters.

[0163] Optionally, in one embodiment of the present application, the receiver demodulation module includes: a demodulation unit, configured to perform baseband digital demodulation on the received signal based on the optimized receiver signal detection parameters.

[0164] It should be noted that the aforementioned explanation of the embodiment of the wireless optical communication method based on the optical intelligent reflective surface is also applicable to the wireless optical communication device based on the optical intelligent reflective surface of this embodiment, and will not be repeated here.

[0165] According to the wireless optical communication device based on the optical intelligent reflection surface proposed in the embodiment of the present application, the optimization of specific goals is achieved by setting the optical intelligent reflection surface, transmitter precoding and receiver signal detection; the transmitter precoding is performed by setting the precoding matrix to change the signal distribution at the transmitting end; the non-line-of-sight path signal of the wireless optical communication is changed by adjusting the parameters of the optical intelligent reflection surface; and the receiver signal detection is performed by setting the signal detection matrix, so that the embodiment of the present application can adjust the signal of the non-line-of-sight path in the wireless optical communication, and by optimizing the optical intelligent reflection surface, the precoding matrix and the signal detection matrix, the mean square error and bit error rate of the wireless optical communication system are effectively reduced, the impact of obstacles on the wireless optical communication is reduced, the receiver signal-to-noise ratio is increased, and the system communication performance is improved.

[0166] Figure 5 A schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include:

[0167] A memory 501 , a processor 502 , and a computer program stored in the memory 501 and executable on the processor 502 .

[0168] When the processor 502 executes the program, the wireless optical communication method based on the optical smart reflective surface provided in the above embodiment is implemented.

[0169] Furthermore, the electronic device further comprises:

[0170] The communication interface 503 is used for communication between the memory 501 and the processor 502 .

[0171] The memory 501 is used to store computer programs that can be executed on the processor 502 .

[0172] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory (non-volatile memory), such as at least one disk memory.

[0173] If the memory 501, the processor 502 and the communication interface 503 are implemented independently, the communication interface 503, the memory 501 and the processor 502 can be connected to each other through a bus and communicate with each other. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component (PCI) bus or an Extended Industry Standard Architecture (EISA) bus. The bus can be divided into an address bus, a data bus, a control bus, etc. For ease of representation, Figure 5 Only one thick line is used in the diagram, but this does not mean that there is only one bus or only one type of bus.

[0174] Optionally, in a specific implementation, if the memory 501, the processor 502 and the communication interface 503 are integrated on a chip, the memory 501, the processor 502 and the communication interface 503 can communicate with each other through an internal interface.

[0175] The processor 502 may be a central processing unit (CPU), or an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0176] An embodiment of the present application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the above-mentioned wireless optical communication method based on an optical smart reflective surface.

[0177] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0178] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0179] Any process or method description in a flowchart or otherwise described herein may be understood to represent a module, fragment or portion of code comprising one or N executable instructions for implementing the steps of a custom logical function or process, and the scope of the preferred embodiments of the present application includes alternative implementations in which functions may not be performed in the order shown or discussed, including performing functions in a substantially simultaneous manner or in reverse order depending on the functions involved, which should be understood by technicians in the technical field to which the embodiments of the present application belong.

[0180] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as an ordered list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by an instruction execution system, device or apparatus (such as a computer-based system, a system including a processor, or other system that can fetch instructions from an instruction execution system, device or apparatus and execute instructions), or in combination with these instruction execution systems, devices or apparatuses. For the purpose of this specification, "computer-readable medium" can be any device that can contain, store, communicate, propagate or transmit a program for use by an instruction execution system, device or apparatus, or in combination with these instruction execution systems, devices or apparatuses. More specific examples of computer-readable media (a non-exhaustive list) include the following: an electrical connection with one or N wirings (electronic devices), a portable computer disk box (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable and programmable read-only memory (EPROM or flash memory), a fiber optic device, and a portable compact disk read-only memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program is printed, since the program may be obtained electronically by optically scanning the paper or other medium and then editing, interpreting or processing in other suitable ways as necessary and then storing it in a computer memory.

[0181] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware or a combination thereof. In the above embodiment, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. If implemented by hardware, as in another embodiment, it can be implemented by any one of the following technologies known in the art or their combination: a discrete logic circuit having a logic gate circuit for implementing a logic function for a data signal, a dedicated integrated circuit having a suitable combination of logic gate circuits, a programmable gate array (PGA), a field programmable gate array (FPGA), etc.

[0182] A person skilled in the art may understand that all or part of the steps in the method for implementing the above-mentioned embodiment may be completed by instructing related hardware through a program, and the program may be stored in a computer-readable storage medium, which, when executed, includes one or a combination of the steps of the method embodiment.

[0183] In addition, each functional unit in each embodiment of the present application may be integrated into a processing module, or each unit may exist physically separately, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. If the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0184] The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and cannot be understood as limiting the present application. A person of ordinary skill in the art may change, modify, replace and modify the above embodiments within the scope of the present application.

Claims

1. A wireless optical communication method based on an optical smart reflective surface, characterized in that: The following steps are involved: Optimize optical intelligent reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters for preset targets; The transmitter precoding is performed by setting the precoding matrix to change the signal distribution at the transmitting end; By setting and regulating the optical intelligent reflective surface parameters, the non-line-of-sight path signal of the wireless optical communication is changed; as well as Receiver signal detection is performed by setting up a signal detection matrix.

2. The method according to claim 1, characterized in that The step of optimizing the optical intelligent reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters for a preset target includes: The optimization objectives include, but are not limited to, minimizing the mean square error, minimizing the bit error rate, maximizing the receiver signal-to-noise ratio, maximizing the receiver energy, and maximizing the channel capacity of the wireless optical communication system; The optimization constraints include, but are not limited to, non-negative real number constraints of optical signals, total transmission power constraints, and power constraints of a single transmitting antenna; Optimization methods include but are not limited to alternating optimization algorithms and joint optimization algorithms.

3. The method according to claim 1, characterized in that: The method of optimizing the optical intelligent reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters for the preset target also includes: Based on the channel state information of the line-of-sight path and the non-line-of-sight path and the position information of the transmitter, the optical smart reflection surface and the receiver, the optical smart reflection surface parameters, the transmitter precoding parameters and the receiver signal detection parameters are optimized.

4. The method according to claim 1, characterized in that The precoding matrix is ​​set to perform transmitter precoding to change the signal distribution at the transmitting end, including: After adding preset and DC bias to the modulated symbol sequence, the transmit signal is digitally precoded in the baseband using a preset precoding matrix.

5. The method according to claim 1, characterized in that The method of changing the non-line-of-sight path signal of wireless optical communication by setting the optical intelligent reflective surface parameters comprises: The optical smart reflective surface parameter refers to the alignment relationship between the reflective surface unit and the transceiver antenna; Based on the optimized optical intelligent reflective surface parameters, the reflective unit is aligned with the corresponding transceiver antenna by adjusting the orientation angle of the reflective unit or controlling the voltage.

6. The method according to claim 5, characterized in that The reflective unit is aligned with the corresponding transceiver antenna, comprising: Based on the optimized optical smart reflective surface parameters, the reflective unit and the corresponding transceiver antenna are aligned using a codebook search method or a geometric calculation method.

7. The method according to claim 1, characterized in that The signal detection of the receiver is performed by setting a signal detection matrix, including: The received signal is baseband digitally demodulated based on the optimized receiver signal detection parameters.

8. A wireless optical communication device based on an optical intelligent reflective surface, characterized in that: include: A central control module, used to optimize optical intelligent reflective surface parameters, transmitter precoding parameters and receiver signal detection parameters for preset targets; A transmitter precoding module is used to set a precoding matrix for transmitter precoding to change the signal distribution at the transmitting end; An optical intelligent reflective surface control module, used to set parameters of the optical intelligent reflective surface and change the non-line-of-sight path signal of wireless optical communication; as well as The receiver demodulation module is used to set the signal detection matrix to perform receiver signal detection.

9. An electronic device, characterized in that: include: A memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the program to implement the wireless optical communication method based on the optical smart reflective surface as described in any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: The program is executed by a processor to implement the wireless optical communication method based on an optical smart reflective surface as described in any one of claims 1 to 7.

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