Wireless optical communication system and method based on fully digital reconfigurable intelligent metasurface

Abstract

The present invention provides a wireless optical communication system and method based on a fully digital reconfigurable intelligent metasurface, the system comprising: a control module, at least two light emitting diode LED arrays connected to the control module, and a fully digital reconfigurable intelligent metasurface Omn i‑DRI S module. The system sends an optical signal for communication through the LED array, and bidirectional optical signal transmission in multiple communication spaces can be achieved by controlling the Omn i‑DRI S module. That is, by utilizing the reflection and refraction characteristics of the Omn i‑DRI S module, the Omn i‑DRI S module can not only reflect the optical signal in one communication space, but also refract and transmit the optical signal to another communication space, thereby realizing information transmission across communication spaces. Moreover, the minimum confidentiality rate of optical communication can also be improved through the Omn i‑DRI S module. Therefore, the physical layer security and communication coverage of the optical communication system can be effectively improved.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and in particular to a wireless optical communication system and method based on a fully digital reconfigurable intelligent metasurface. Background Art

[0002] With the rapid development of visible light communication (VLC) technology, wireless optical communication systems have been more widely used. Specifically, VLC technology is a wireless communication technology that uses visible light bands to achieve data transmission. This technology uses light emitting diode (LED) light sources to provide lighting while performing high-speed data communication. Due to its rich spectrum resources, no need for spectrum licenses, high data rates and low power consumption, it has become an important technology for 6G and future wireless communication systems. Compared with traditional radio frequency (RF) communication, optical signals have stronger controllability and physical isolation characteristics. It is difficult for signals to penetrate walls, thus limiting the propagation range and making wireless optical communication systems more secure.

[0003] In the related art, a multi-user wireless optical communication system (hereinafter referred to as RIS-VLC system) assisted by a reconfigurable intelligent reflector surface (RIS) can be used to achieve physical layer security optimization of the wireless optical communication system. However, the coverage of the RIS-VLC system is limited. The RIS can only cover a single room where it is located and cannot be extended to other rooms, and cannot meet the demand for secure communication in multiple rooms. In addition, the RIS-VLC system has high system complexity and poor flexibility. If the information exchange between multiple rooms needs to enhance the security of the physical layer, multiple RIS need to be deployed, which will greatly increase the complexity and cost of the system.

[0004] It can be seen that the existing wireless optical communication system has great limitations in terms of physical layer security and communication coverage, which leads to low physical layer security and communication coverage of the wireless optical communication system. Summary of the invention

[0005] The technical problem to be solved by the present invention is the problem of low physical layer security and communication coverage of a wireless optical communication system.

[0006] In order to solve the above technical problems, the present invention provides a wireless optical communication system and method based on a fully digital reconfigurable intelligent metasurface. The specific technical solutions are as follows:

[0007] In the first aspect, the present invention provides a wireless optical communication system based on a fully digital reconfigurable intelligent metasurface, comprising: a control module, at least two light emitting diode LED arrays connected to the control module, and a fully digital reconfigurable intelligent metasurface Omni-DRIS module. Wherein, the at least two light emitting diode LED arrays include: a first LED array and a second LED array, the first LED array is arranged in a first communication space, the second LED array is arranged in a second communication space, the first communication space is adjacent to the second communication space and there is a common area, and the Omni-DRIS module is arranged in the common area. Wherein, the control module is used to control the first LED array to send a first wireless optical communication signal, and there is a direct line of sight path between the first LED array and the first user device, and when the first wireless optical communication signal is not blocked, the first wireless optical communication signal is sent to the first user device along the direct line of sight path, wherein the first user device is in the first communication space. The control module is also used to control the Omni-DRIS module to reflect the first wireless optical communication signal when there is no direct line of sight path between the first LED array and the first user device, or when the first wireless optical communication signal is blocked, so that the first wireless optical communication signal is received by the first user device. The control module is also used to monitor the signal strength of the first wireless optical communication signal. When the signal strength of the first wireless optical communication signal is less than a preset signal strength, the control module controls the second LED array to send a second wireless optical communication signal, and controls the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user device.

[0008] This wireless optical communication system based on a fully digital reconfigurable intelligent metasurface can send optical signals for communication through an LED array, and can realize bidirectional optical signal transmission in multiple communication spaces by controlling the Omni-DRIS module. This wireless optical communication system utilizes the reflection and refraction characteristics of the Omni-DRIS module. Through the Omni-DRIS module, it can not only reflect optical signals in one communication space, but also refract and transmit optical signals to another communication space, thereby realizing information transmission across communication spaces. In addition, the minimum confidentiality rate of the wireless optical communication system can be improved through the Omni-DRIS module. Therefore, the physical layer security and communication coverage of the optical communication system can be effectively improved through this system.

[0009] In combination with the first aspect, in an optional implementation, the Omni-DRIS module includes: multiple control units. In controlling the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user device, the control module is specifically used to: first, obtain the transmission power, first channel gain parameter and first position information of the first LED array; wherein the first channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first user device, and the first position information is used to characterize the position of the first user device in the first communication space. Then, the reflection angle of at least one control unit among the multiple control units is determined according to the transmission power, first channel gain parameter and first position information of the first LED array, so that at least one control unit reflects the first wireless optical communication signal to the first user device.

[0010] In this implementation, the control module can effectively determine the reflection angle of the control unit in the Omni-DRIS module according to the transmission power of the first LED array, the first channel gain parameter and the first position information, and efficiently and accurately reflect the first wireless optical communication signal to the first user device.

[0011] In combination with the first aspect, in an optional implementation, in controlling the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user device, the control module is specifically used to: first, obtain the transmission power of the second LED array. Then, according to the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information, determine the refraction angle of at least one control unit among the multiple control units, so that the at least one control unit refracts the second wireless optical communication signal to the first user device.

[0012] In this implementation, the control module can effectively determine the refraction angle of the control unit in the Omni-DRIS module based on the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information, and efficiently and accurately refract the second wireless optical communication signal to the first user device.

[0013] In combination with the first aspect, in an optional implementation, the control module is specifically used to determine the refraction angle of at least one control unit among a plurality of control units through an alternating optimization algorithm and a successive convex approximation algorithm based on the emission power of the first LED array, the emission power of the second LED array, the first channel gain parameter and the first position information.

[0014] In combination with the first aspect, in an optional implementation, the control module is specifically used to determine the refraction angle of at least one control unit among multiple control units through a global optimization algorithm based on the emission power of the first LED array, the emission power of the second LED array, the first channel gain parameter and the first position information.

[0015] In combination with the first aspect, in an optional implementation, the system also includes: a first noise LED module, the first noise LED module is connected to the control module, and the first noise LED module is arranged in the second communication space. The control module is also used to: monitor whether there is a first illegal monitoring device and a second illegal monitoring device, wherein the first illegal monitoring device is in the first communication space and the second illegal monitoring device is in the second communication space. In the case of the presence of the first illegal monitoring device, the first noise LED module is controlled to send a first preset interference signal, and the Omni-DRIS module is controlled to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device. In the case of the presence of the second illegal monitoring device, the first noise LED module is controlled to send the first preset interference signal to the second illegal monitoring device.

[0016] In this implementation, a preset interference signal can be sent to an illegal monitoring device through the first noise LED module. And the preset interference signal is transmitted to the illegal monitoring device in a directional manner through the Omni-DRIS module to ensure that the location of the illegal monitoring device is effectively covered, while not interfering with other legitimate user devices, thereby further improving the physical layer security of the wireless optical communication system.

[0017] In combination with the first aspect, in an optional implementation, in controlling the Omni-DRIS module to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device, the control module is specifically used to: first, obtain the second channel gain parameter and the second position information; wherein the second channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first illegal monitoring device, and the second position information is used to characterize the position of the first illegal monitoring device in the first communication space. Then, the target direction of the first preset interference signal is determined according to the second channel gain parameter and the second position information, and the refraction angle of at least one control unit in the Omni-DRIS module is determined according to the target direction, so that the at least one control unit refracts the first preset interference signal to the first illegal monitoring device.

[0018] In this implementation, the control module can effectively determine the refraction angle of the control unit in the Omni-DRIS module according to the second channel gain parameter and the second location information, and efficiently and accurately refract the first preset interference signal to the first illegal monitoring device.

[0019] In combination with the first aspect, in an optional implementation, the system further includes: a second noise LED module, the second noise LED module is connected to the control module, and the second noise LED module is arranged in the first communication space. The control module is also used for: in the presence of the first illegal monitoring device, controlling the second noise LED module to send a second preset interference signal to the first illegal monitoring device. In the presence of the second illegal monitoring device, controlling the second noise LED module to send a second preset interference signal, and controlling the Omni-DRIS module to refract the second preset interference signal so that the second preset interference signal is received by the second illegal monitoring device.

[0020] In this implementation, the second noise LED module can further increase the interference to illegal monitoring devices, thereby further improving the physical layer security of the wireless optical communication system.

[0021] In combination with the first aspect, in an optional implementation, the first preset interference signal is a signal orthogonal to the first wireless optical communication signal, and / or the second preset interference signal is a signal orthogonal to the second wireless optical communication signal.

[0022] In a second aspect, the present invention provides a wireless optical communication method based on a fully digital reconfigurable intelligent metasurface, which can be applied to a wireless optical communication system, wherein the wireless optical communication system comprises: a first LED array, a second LED array and an Omni-DRIS module; wherein the first LED array is arranged in a first communication space, the second LED array is arranged in a second communication space, the first communication space is adjacent to the second communication space and there is a common area, and the Omni-DRIS module is arranged in the common area. The method comprises: controlling the first LED array to send a first wireless optical communication signal, wherein there is a direct line of sight path between the first LED array and the first user device, and when the first wireless optical communication signal is not blocked, the first wireless optical communication signal is sent to the first user device along the direct line of sight path, wherein the first user device is in the first communication space. When there is no direct line of sight path between the first LED array and the first user device, or when the first wireless optical communication signal is blocked, controlling the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user device. Monitor the signal strength of the first wireless optical communication signal, and when the signal strength of the first wireless optical communication signal is less than the preset signal strength, control the second LED array to send the second wireless optical communication signal, and control the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user device.

[0023] It can be understood that the beneficial effects that can be achieved by the wireless optical communication method based on the fully digital reconfigurable intelligent metasurface provided by the second aspect above can refer to the beneficial effects in the first aspect and any possible design method thereof, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic diagram of the architecture of a wireless optical communication system based on a fully digital reconfigurable intelligent metasurface provided in an embodiment of the present invention;

[0025] Figure 2 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 1 ;

[0026] Figure 3 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 2 ;

[0027] Figure 4 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 3 ;

[0028] Figure 5 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 4 ;

[0029] Figure 6 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 1 ;

[0030] Figure 7 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 2 ;

[0031] Figure 8 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 3 ;

[0032] Fig. 9 A schematic flow chart of a wireless optical communication method based on a fully digital reconfigurable intelligent metasurface provided in an embodiment of the present invention. DETAILED DESCRIPTION

[0033] The following embodiments are described in detail, and examples thereof are shown in the accompanying drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The implementations described in the following embodiments do not represent all implementations consistent with the present application. They are only examples of systems and methods consistent with some aspects of the present application as detailed in the claims.

[0034] Wireless optical communication systems can use RIS-VLC systems to achieve physical layer security optimization. However, the coverage of the RIS-VLC system is limited. RIS can only cover the single room where it is located and cannot be expanded to other rooms. It cannot meet the demand for secure communication in multiple rooms. In addition, the RIS-VLC system has high system complexity and poor flexibility. If the information exchange between multiple rooms needs to enhance the security of the physical layer, multiple RIS need to be deployed, which will greatly increase the complexity and cost of the system.

[0035] It can be seen that the existing wireless optical communication system has great limitations in terms of physical layer security and communication coverage, which leads to low physical layer security and communication coverage of the wireless optical communication system.

[0036] In order to solve the above problems, the embodiment of the present application provides a wireless optical communication system and method based on a fully digital reconfigurable intelligent metasurface, which can be applied to two communication spaces (such as closed rooms) or indoor communication scenarios requiring high security. Specifically, the system includes: a control module, at least two LED arrays connected to the control module, and a fully digital reconfigurable intelligent metasurface Omni-DRIS module. The system can send optical signals for communication through the LED array, and bidirectional optical signal transmission in multiple communication spaces can be achieved by controlling the Omni-DRIS module. That is, by utilizing the reflection and refraction characteristics of the Omni-DRIS module, the Omni-DRIS module can not only reflect optical signals in one communication space, but also refract and transmit optical signals to another communication space, thereby realizing information transmission across communication spaces. Moreover, the minimum confidentiality rate of the wireless optical communication system can be improved by the Omni-DRIS module. Therefore, the physical layer security and communication coverage of the optical communication system can be effectively improved by the system.

[0037] The solution provided by the embodiment of the present application is introduced below in conjunction with the accompanying drawings.

[0038] For details, see Figure 1 , which is a schematic diagram of the architecture of a wireless optical communication system based on a fully digital reconfigurable intelligent metasurface provided by an embodiment of the present invention, such as Figure 1 As shown, the wireless optical communication system 10 based on the fully digital reconfigurable intelligent metasurface provided by the present invention includes: a control module 100, at least two LED arrays connected to the control module 100, and an Omni-DRIS module 300. Among them, the at least two LED arrays include: a first LED array 201 and a second LED array 202.

[0039] The first LED array is arranged in the first communication space, the second LED array is arranged in the second communication space, the first communication space is adjacent to the second communication space and there is a common area, and the Omni-DRIS module is arranged in the common area. Specifically, the first communication space and the second communication space may be two adjacent rooms, and the common area between the first communication space and the second communication space may be a common wall.

[0040] Exemplarily, it is taken that the first communication space is the first room, the second communication space is the second room, and the common area is the common wall. Figure 2 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 1 ,like Figure 2 As shown, the first LED array 201 can be set on the top of the first room 21, the second LED array 202 can be set on the top of the second room 22, and the Omni-DRIS module 300 can be set on the common wall 23.

[0041] Specifically, the first LED array and the second LED array may both be composed of a plurality of LED lamps, and the first LED array and the second LED array may emit wireless optical communication signals of target power to achieve communication data transmission.

[0042] The control module can be used to control the first LED array to send a first wireless optical communication signal. When there is a direct line of sight path between the first LED array and the first user device, and the first wireless optical communication signal is not blocked, the first wireless optical communication signal can be sent to the first user device along the direct line of sight path. The first user device is in the first communication space.

[0043] Specifically, continue with Figure 2 Taking the application scenario shown as an example, the first user device 31 is in the first room 21, and the first user device 31 is a legitimate device that has been authenticated or authorized by the wireless optical communication system provided by the present invention, that is, the first user device 31 can receive the first wireless optical communication signal. There is a line of sight (LOS) A between the first LED array 201 and the first user device 31, and when the first wireless optical communication signal is not blocked, the first wireless optical communication signal can be sent to the first user device 31 along the line of sight A, so that the first user device 31 receives the first wireless optical communication signal.

[0044] In an embodiment of the present invention, the control module can also be used to control the Omni-DRIS module to reflect the first wireless optical communication signal when there is no direct line of sight between the first LED array and the first user device, or when the first wireless optical communication signal is blocked, so that the first wireless optical communication signal is received by the first user device.

[0045] In one implementation, the control module can determine whether there is a direct line of sight path between the first LED array and the first user device, and whether the first wireless optical communication signal is blocked, through channel model measurement. Specifically, the control module can calculate and measure the signal gain of each channel through the LOS channel model of the VLC system. For example, by calculating the channel gain of the transmitter and the photodetector (PD) of the first LED array, if the gain value drops sharply, it can be determined that there is no direct line of sight path, or the first wireless optical communication signal is blocked.

[0046] In another implementation, the control module can also determine whether there is signal obstruction in the first wireless optical communication signal by detecting parameters such as the incident angle and the reflection angle. When the incident angle and the reflection angle cannot reach the angle threshold preset by the wireless optical communication system, it can be determined that there is no direct line of sight path or the first wireless optical communication signal is obstructed.

[0047] Among them, the Omni-DRIS module is a module that uses Omni-DRIS's wireless optical communication enhancement technology. The Omni-DRIS module can dynamically adjust the reflection and refraction paths of optical signals to optimize the reception conditions of optical signals. Unlike traditional RIS, Omni-DRIS can not only reflect optical signals, but also refract them, so that optical signals can cover multiple communication spaces at the same time, such as multiple adjacent rooms. By deploying Omni-DRIS modules on the common wall between two rooms, two-way signal transmission and coverage can be achieved simultaneously to significantly expand the communication range. Especially in complex scenarios where it is necessary to prevent eavesdropping and ensure the quality of multi-user communications, the two-way coverage capability of the Omni-DRIS module can effectively enhance the physical layer security of the VLC system.

[0048] Specifically, the Omni-DRIS module may include: a plurality of control units, which may be controlled by a control module. That is, the Omni-DRIS module may be composed of a plurality of programmable control units, each of which may work as a reflection unit or a refraction unit. The control module may dynamically adjust the working state (e.g., reflection state, refraction state) of the control unit in the Omni-DRIS module according to the communication application requirements, so that the propagation of the optical signal (e.g., the first wireless optical communication signal) between multiple communication spaces is more flexible and directional, thereby covering different communication spaces.

[0049] In some embodiments, in controlling the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user equipment, the control module may be specifically used to:

[0050] First, the transmission power, the first channel gain parameter and the first position information of the first LED array are obtained; wherein the first channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first user device, and the first position information is used to characterize the position of the first user device in the first communication space.

[0051] Then, the reflection angle of at least one control unit among the multiple control units is determined according to the transmission power of the first LED array, the first channel gain parameter and the first position information, so that the at least one control unit reflects the first wireless optical communication signal to the first user equipment.

[0052] In one implementation, the control module can determine the reflection angle of at least one control unit among a plurality of control units based on the transmission power of the first LED array, the first channel gain parameter and the first position information through an alternating optimization (AO) algorithm and a successive convex approximation (SCA) algorithm, so that the at least one control unit reflects the first wireless optical communication signal to the first user device.

[0053] For example, continue with Figure 2 Taking the application scenario shown as an example, the control module 100 can control the reflection angle of at least one control unit in the Omni-DRIS module 300, so that the at least one control unit reflects the first wireless optical communication signal along the non-line-of-sight transmission path (NLOS) B to the first user device 31, so that the first user device 31 receives the reflected first wireless optical communication signal.

[0054] In this way, when there is no direct line of sight path between the first LED array and the first user device, or when the first wireless optical communication signal is blocked, the control module can control the reflection angle of the control unit in the Omni-DRIS module to provide an indirect non-direct line of sight transmission path to transmit the first wireless optical communication signal, thereby allowing the first wireless optical communication signal to bypass obstacles and be received by the first user device.

[0055] In an embodiment of the present invention, the control module is also used to monitor the signal strength of the first wireless optical communication signal, and when the signal strength of the first wireless optical communication signal is less than a preset signal strength, control the second LED array to send a second wireless optical communication signal, and control the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user device.

[0056] Specifically, the control module can monitor the signal strength of the first wireless optical communication signal. If the first wireless optical communication signal can effectively reach the first user device, the wireless optical communication system preferentially uses the first LED array. When the signal strength of the first wireless optical communication signal is less than the preset signal strength due to interference and other problems, the control module can also control the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user device, thereby enhancing the signal strength of the wireless optical communication signal received by the first user device.

[0057] The transmission data of the second wireless optical communication signal and the first wireless optical communication signal may be the same. The transmission power of the second wireless optical communication signal may be the same as or different from the transmission power of the first wireless optical communication signal. The specific transmission power of the second wireless optical communication signal and the first wireless optical communication signal may be adjusted according to actual application requirements.

[0058] In one implementation, the control module can monitor the signal strength of the first wireless optical communication signal through channel gain calculation and channel model. Specifically, the wireless optical communication system provided by the embodiment of the present invention can adopt a channel model based on LOS (line-of-sight path) and NLOS (non-line-of-sight path), and the control module can determine the signal strength of the signal path by calculating the channel gain (for example, including: distance, incident angle, reflection angle and other parameters) between each LED and the receiver (such as the first user device).

[0059] In some embodiments, in controlling the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user equipment, the control module is specifically used to:

[0060] First, the emission power of the second LED array is obtained.

[0061] Then, the refraction angle of at least one control unit among the multiple control units is determined according to the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information, so that the at least one control unit refracts the second wireless optical communication signal to the first user device.

[0062] In some embodiments, the control module is specifically used to determine the refraction angle of at least one control unit among multiple control units through an alternating optimization algorithm and a successive convex approximation algorithm based on the emission power of the first LED array, the emission power of the second LED array, the first channel gain parameter and the first position information.

[0063] In one implementation, the control module can also determine the optimized transmission powers of the first LED array and the second LED array according to the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information through an alternating optimization algorithm and a successive convex approximation algorithm to improve the signal strength and stability of the first wireless optical communication signal and the second wireless optical communication signal received by the first user device.

[0064] In some embodiments, the control module is further specifically used to determine the refraction angle of at least one control unit among the plurality of control units through a global optimization algorithm according to the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information. The global optimization algorithm may include, for example, a genetic algorithm, a particle swarm optimization algorithm, etc.

[0065] For example, continue with Figure 2 Taking the application scenario shown as an example, the control module 100 can control the refraction angle of at least one control unit in the Omni-DRIS module 300, so that at least one control unit refracts the second wireless optical communication signal along path C to the first user device, so that the first user device 31 receives the refracted second wireless optical communication signal.

[0066] In this way, the control module can control the refraction angle of the control unit in the Omni-DRIS module to refract the second wireless optical communication signal emitted by the second LED array in the second communication space to the first user device, thereby realizing the transmission of wireless optical communication signals across communication spaces to cover user devices in multiple communication spaces, thereby ensuring the connectivity and stability of wireless optical communication and effectively improving the coverage of wireless optical communication signals.

[0067] In some embodiments, there is a second user device in the second communication space, and the second user device is a legitimate device authenticated or authorized by the wireless optical communication system provided by the present invention, that is, the second user device can receive the second wireless optical communication signal. Figure 3 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 2 ,like Figure 3 As shown, the control module 100 can also be used for:

[0068] The second LED array 202 is controlled to send a second wireless optical communication signal. When there is a line-of-sight path D between the second LED array 202 and the second user device 32 and the second wireless optical communication signal is not blocked, the second wireless optical communication signal is sent to the second user device 32 along the line-of-sight path D.

[0069] When there is no direct line of sight path between the second LED array 202 and the second user device 32, or when the second wireless optical communication signal is blocked, the control module 100 controls the Omni-DRIS module 300 to reflect the second wireless optical communication signal, so that the second wireless optical communication signal is reflected along the non-direct line of sight transmission path E to the second user device 32, so that the second user device 32 receives the reflected second wireless optical communication signal.

[0070] The control module 100 is also used to monitor the signal strength of the second wireless optical communication signal. When the signal strength of the second wireless optical communication signal is less than the preset signal strength, the control module 100 controls the first LED array 201 to send the first wireless optical communication signal, and controls the Omni-DRIS module 300 to refract the first wireless optical communication signal along the path F to the second user device 32, so that the second user device 32 receives the refracted first wireless optical communication signal.

[0071] The wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention utilizes the reflection and refraction characteristics of the Omni-DRIS module. The Omni-DRIS module can not only reflect the optical signal in one communication space, but also refract and transmit the optical signal to another communication space, thereby realizing information transmission across communication spaces. Moreover, the Omni-DRIS module can improve the minimum confidentiality rate of the wireless optical communication system. Therefore, the system can effectively improve the physical layer security and communication coverage of the optical communication system.

[0072] In some application scenarios, there may be illegal monitoring devices in the first communication space and the second communication space. In order to improve the physical layer security of the wireless optical communication system, the wireless optical communication system provided by the embodiment of the present invention may also include a noise LED to transmit interference signals to the illegal monitoring devices, so as to weaken the quality of the wireless optical communication signals received by the illegal monitoring devices and prevent the illegal monitoring devices from eavesdropping.

[0073] Specifically, in some embodiments, Figure 1 As shown, the wireless optical communication system 10 based on the fully digital reconfigurable intelligent metasurface provided by the present invention further includes: a first noise LED module 401, and the first noise LED module 401 is connected to the control module 100. The first noise LED module can be set in the second communication space.

[0074] Exemplarily, it is taken that the first communication space is the first room and the second communication space is the second room. Figure 4 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 3 ,like Figure 4As shown, the first noise LED module 401 can be set at the top of the second room 22.

[0075] When the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the present invention further includes a first noise LED module, the control module is further used for:

[0076] First, the control module monitors whether there is a first illegal monitoring device and a second illegal monitoring device, wherein the first illegal monitoring device is in the first communication space and the second illegal monitoring device is in the second communication space.

[0077] Specifically, the first illegal monitoring device and the second illegal monitoring device are illegal devices that have not been authenticated or authorized by the wireless optical communication system provided by the present invention, that is, the first illegal monitoring device and the second illegal monitoring device cannot receive the first wireless optical communication signal.

[0078] In one implementation, the control module may determine whether there are the first illegal monitoring device and the second illegal monitoring device according to the channel gain and signal strength of the optical communication signal in the first communication space and the second communication space and the location information of the receiving device.

[0079] Furthermore, in the presence of a first illegal monitoring device, the control module can control the first noise LED module to send a first preset interference signal, and control the Omni-DRIS module to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device.

[0080] In some embodiments, the control module controls the Omni-DRIS module to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device, specifically including:

[0081] First, the control module obtains a second channel gain parameter and a second position information, wherein the second channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first illegal monitoring device, and the second position information is used to characterize the position of the first illegal monitoring device in the first communication space.

[0082] Then, the control module determines the target direction of the first preset interference signal according to the second channel gain parameter and the second position information, and determines the refraction angle of at least one control unit in the Omni-DRIS module according to the target direction, so that the at least one control unit refracts the first preset interference signal to the first illegal monitoring device.

[0083] like Figure 4As shown, the control module 100 can control the Omni-DRIS module 300 to refract the first preset interference signal emitted by the first noise LED module 401 to the first illegal monitoring device 41 to interfere with the illegal monitoring of the first illegal monitoring device 41.

[0084] Furthermore, when there is a second illegal monitoring device, the control module may control the first noise LED module to send a first preset interference signal to the second illegal monitoring device.

[0085] like Figure 4 As shown, the control module 100 can control the first noise LED module 401 to send a first preset interference signal to the second illegal monitoring device 42 to interfere with the illegal monitoring of the second illegal monitoring device 42 .

[0086] Among them, the above-mentioned first preset interference signal can be preset according to the first wireless optical communication signal sent by the first LED array and actual application requirements, and can be adjusted during the application process.

[0087] In some embodiments, the first preset interference signal may be a signal orthogonal to the first wireless optical communication signal, so as to avoid interference with the communication of a legitimate user (such as the first user equipment).

[0088] In some embodiments, in order to further increase the interference to illegal monitoring devices, the physical layer security of the wireless optical communication system is improved. Figure 1 As shown, the wireless optical communication system 10 based on the fully digital reconfigurable intelligent metasurface provided by the present invention may further include: a second noise LED module 402, and the second noise LED module 402 is connected to the control module 100. The second noise LED module is arranged in the first communication space.

[0089] Exemplarily, it is taken that the first communication space is the first room and the second communication space is the second room. Figure 5 Schematic diagram of application scenarios of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention Figure 4 ,like Figure 5 As shown, the second noise LED module 402 can be set at the top of the first room 21.

[0090] When the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the present invention further includes a second noise LED module, the control module is further used for:

[0091] When the first illegal monitoring device exists, the control module controls the second noise LED module to send a second preset interference signal to the first illegal monitoring device.

[0092] like Figure 5As shown, the control module 100 can control the second noise LED module 402 to send a second preset interference signal to the first illegal monitoring device 41 to interfere with the illegal monitoring of the first illegal monitoring device 41.

[0093] When there is a second illegal monitoring device, the control module controls the second noise LED module to send a second preset interference signal, and controls the Omni-DRIS module to refract the second preset interference signal so that the second preset interference signal is received by the second illegal monitoring device.

[0094] like Figure 5 As shown, the control module 100 can control the Omni-DRIS module 300 to refract the second preset interference signal emitted by the second noise LED module 402 to the second illegal monitoring device 42 to interfere with the illegal monitoring of the second illegal monitoring device 42.

[0095] Among them, the above-mentioned second preset interference signal can be preset according to the first wireless optical communication signal sent by the first LED array and actual application requirements, and can be adjusted during the application process.

[0096] In some embodiments, the second preset interference signal may be a signal orthogonal to the first wireless optical communication signal, so as to avoid interference with the communication of a legitimate user (such as the first user equipment).

[0097] It can be seen that the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention can send a preset interference signal to the illegal monitoring device through the noise LED module. And the preset interference signal is transmitted to the illegal monitoring device in a directional manner through the Omni-DRIS module to ensure that the location of the illegal monitoring device is effectively covered, and other legitimate user devices will not be interfered with, thereby further improving the physical layer security of the wireless optical communication system.

[0098] In order to verify the effectiveness of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention in improving the physical layer security and the minimum confidentiality rate of the wireless optical communication system, a simulation experiment was carried out.

[0099] Figure 6 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 1 For different transmission powers of the first LED array, the number of control units of different Omni-DRIS modules in the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface (hereinafter referred to as the Omni-DRIS system) provided by the embodiment of the present invention and the RIS-VLC system are simulated and compared to determine the corresponding minimum confidentiality rate. Figure 6As shown in the figure, when there are two legitimate user devices in the wireless optical communication system and the transmission power is 25 dBm, the minimum confidentiality rate of N = 225 (N is the number of control units in the Omni-DRIS module) is 1.39 times, 2.31 times and 3.24 times that of N = 100, N = 25 and RIS-VLC systems respectively. Figure 6 As shown, as N increases, the improvement speed of the minimum confidentiality rate (ie, security) of the wireless optical communication system slows down, thereby confirming the importance of the Omni-DRIS module in improving the security performance of the wireless optical communication system.

[0100] Figure 7 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 2 The minimum confidentiality rates of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface with precoding (hereinafter referred to as the Omni-DRIS system), the Omni-DRIS system without precoding, and the RIS-VLC system are simulated and compared when the number of user devices (K) is 2 and 6, respectively. Figure 7 As shown, under the same transmission power conditions, compared with the traditional RIS-VLC system, the Omni-DRIS system of the present invention can significantly improve the minimum confidentiality rate (i.e., security) of the wireless optical communication system. In a multi-user scenario, the Omni-DRIS system can not only achieve a higher secure communication data rate, but also effectively deal with potential eavesdropper interference. For example, when there are 2 legitimate users in the system and the transmission power is 25dBm, the minimum confidentiality rate of the Omni-DRIS system is about 2.05 times higher than that of the traditional RIS-VLC system. Therefore, the Omni-DRIS system provided in the embodiment of the present invention can significantly improve the secure communication data rate

[0101] Figure 8 The simulation results provided by the embodiment of the present invention are shown in FIG. Figure 3 , the minimum confidentiality rates obtained by using different numbers of iterations are simulated and compared under different numbers (K) of user devices and different numbers (N) of control units in the Omni-DRIS module. Figure 8 As shown in the figure, with the increase of iteration number, the minimum confidentiality rate of Omni-DRIS system gradually increases and finally converges. A larger number of control units in the Omni-DRIS module can speed up the convergence of Omni-DRIS system, which proves the effectiveness and convergence of the simulation algorithm under various system parameters.

[0102] Through the above simulation experiments, the effectiveness of the wireless optical communication system based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention in improving the minimum confidentiality rate and physical layer security of the wireless optical communication system is verified. The simulation results show that compared with the traditional RIS-VLC system, the Omni-DRIS system has a significantly improved security rate under the conditions of higher transmission power and more reflection units, and can better resist interference from eavesdroppers.

[0103] The embodiment of the present invention also provides a wireless optical communication method based on a fully digital reconfigurable intelligent metasurface, which can be applied to the wireless optical communication system based on a fully digital reconfigurable intelligent metasurface shown in the above embodiment. Specifically, Fig. 9 A schematic diagram of a wireless optical communication method based on a fully digital reconfigurable intelligent metasurface provided in an embodiment of the present invention is shown in FIG. Fig. 9 As shown, the method includes the following steps S101-S104:

[0104] S101. Control the first LED array to send a first wireless optical communication signal. When there is a line-of-sight path between the first LED array and the first user device and the first wireless optical communication signal is not blocked, the first wireless optical communication signal is sent to the first user device along the line-of-sight path, wherein the first user device is in a first communication space.

[0105] S102: When there is no direct line of sight between the first LED array and the first user device, or when the first wireless optical communication signal is blocked, control the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user device.

[0106] S103: Monitor the signal strength of the first wireless optical communication signal.

[0107] S104. When the signal strength of the first wireless optical communication signal is less than the preset signal strength, control the second LED array to send a second wireless optical communication signal, and control the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user equipment.

[0108] By using the wireless optical communication method based on the fully digital reconfigurable intelligent metasurface provided by the embodiment of the present invention, the reflection and refraction characteristics of the Omni-DRIS module are utilized. The Omni-DRIS module can not only reflect the optical signal in one communication space, but also refract and transmit the optical signal to another communication space, thereby realizing information transmission across communication spaces. Moreover, the Omni-DRIS module can improve the minimum confidentiality rate of the wireless optical communication system. Therefore, the method can effectively improve the physical layer security and communication coverage of the optical communication system.

[0109] Through the description of the above implementation methods, technical personnel in the relevant field can clearly understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be assigned to different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0110] In the description of the present invention, it should be understood that 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. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0111] 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 invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more 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.

[0112] Similar parts between the embodiments provided in this application can be referenced to each other. The specific implementation methods provided above are only a few examples under the general concept of this application and do not constitute a limitation on the protection scope of this application. For those skilled in the art, any other implementation methods expanded based on the scheme of this application without creative work belong to the protection scope of this application.

Claims

1. A wireless optical communication system based on a fully digital reconfigurable intelligent metasurface, characterized in that: include: A control module, at least two light emitting diode (LED) arrays connected to the control module, a fully digital reconfigurable intelligent metasurface Omni-DRIS module, and a first noise LED module; wherein the at least two light emitting diode (LED) arrays include: a first LED array and a second LED array, the first LED array is arranged in a first communication space, the second LED array is arranged in a second communication space, the first communication space is adjacent to the second communication space and there is a common area, the Omni-DRIS module is arranged in the common area, and the first noise LED module is arranged in the second communication space; The control module is used to control the first LED array to send a first wireless optical communication signal, and when there is a direct line of sight path between the first LED array and the first user device, and when the first wireless optical communication signal is not blocked, the first wireless optical communication signal is sent to the first user device along the direct line of sight path, wherein the first user device is in the first communication space; The control module is further configured to control the Omni-DRIS module to reflect the first wireless optical communication signal when there is no direct line of sight between the first LED array and the first user equipment, or when the first wireless optical communication signal is blocked, so that the first wireless optical communication signal is received by the first user equipment; The control module is further configured to monitor the signal strength of the first wireless optical communication signal, and when the signal strength of the first wireless optical communication signal is less than a preset signal strength, control the second LED array to send a second wireless optical communication signal, and control the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user equipment; The control module is further used to monitor whether there is a first illegal monitoring device and a second illegal monitoring device, wherein the first illegal monitoring device is in the first communication space and the second illegal monitoring device is in the second communication space; in the case of the presence of the first illegal monitoring device, the first noise LED module is controlled to send a first preset interference signal, and the Omni-DRIS module is controlled to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device; in the case of the presence of the second illegal monitoring device, the first noise LED module is controlled to send the first preset interference signal to the second illegal monitoring device; The control module is also specifically used to obtain a second channel gain parameter and a second position information; wherein the second channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first illegal monitoring device, and the second position information is used to characterize the position of the first illegal monitoring device in the first communication space; the target direction of the first preset interference signal is determined according to the second channel gain parameter and the second position information, and the refraction angle of at least one control unit in the Omni-DRIS module is determined according to the target direction, so that the at least one control unit refracts the first preset interference signal to the first illegal monitoring device.

2. The system according to claim 1, characterized in that The Omni-DRIS module includes: a plurality of control units; In controlling the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user equipment, the control module is specifically used to: Acquire the transmission power, the first channel gain parameter and the first position information of the first LED array; wherein the first channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first user equipment, and the first position information is used to characterize the position of the first user equipment in the first communication space; The reflection angle of at least one control unit among the multiple control units is determined according to the transmission power of the first LED array, the first channel gain parameter and the first position information, so that the at least one control unit reflects the first wireless optical communication signal to the first user equipment.

3. The system according to claim 2, characterized in that In controlling the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user equipment, the control module is specifically used to: Acquire the emission power of the second LED array; Determine the refraction angle of at least one control unit among the multiple control units based on the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information, so that the at least one control unit refracts the second wireless optical communication signal to the first user device.

4. The system according to claim 3, characterized in that The control module is specifically used for: According to the emission power of the first LED array, the emission power of the second LED array, the first channel gain parameter and the first position information, the refraction angle of at least one control unit among the multiple control units is determined by an alternating optimization algorithm and a successive convex approximation algorithm.

5. The system according to claim 3, characterized in that The control module is specifically used to determine the refraction angle of at least one control unit among the multiple control units through a global optimization algorithm according to the transmission power of the first LED array, the transmission power of the second LED array, the first channel gain parameter and the first position information.

6. The system according to claim 1, characterized in that The system further comprises: a second noise LED module, the second noise LED module is connected to the control module, and the second noise LED module is arranged in the first communication space; the control module is further used for: In the case where the first illegal monitoring device exists, controlling the second noise LED module to send a second preset interference signal to the first illegal monitoring device; In the case where the second illegal monitoring device exists, the second noise LED module is controlled to send the second preset interference signal, and the Omni-DRIS module is controlled to refract the second preset interference signal so that the second preset interference signal is received by the second illegal monitoring device.

7. The system according to claim 6, characterized in that The first preset interference signal is a signal orthogonal to the first wireless optical communication signal, and / or the second preset interference signal is a signal orthogonal to the second wireless optical communication signal.

8. A wireless optical communication method based on a fully digital reconfigurable intelligent metasurface, characterized in that: Applied to a wireless optical communication system, the wireless optical communication system comprises: a first LED array, a second LED array, an Omni-DRIS module and a first noise LED module; wherein the first LED array is arranged in a first communication space, the second LED array is arranged in a second communication space, the first communication space is adjacent to the second communication space and there is a common area, the Omni-DRIS module is arranged in the common area, and the first noise LED module is arranged in the second communication space; the method comprises: Controlling the first LED array to send a first wireless optical communication signal, where there is a direct line of sight path between the first LED array and a first user device, and the first wireless optical communication signal is not blocked, the first wireless optical communication signal is sent to the first user device along the direct line of sight path, wherein the first user device is in the first communication space; When there is no direct line of sight between the first LED array and the first user equipment, or when the first wireless optical communication signal is blocked, control the Omni-DRIS module to reflect the first wireless optical communication signal so that the first wireless optical communication signal is received by the first user equipment; monitoring the signal strength of the first wireless optical communication signal, and when the signal strength of the first wireless optical communication signal is less than a preset signal strength, controlling the second LED array to send a second wireless optical communication signal, and controlling the Omni-DRIS module to refract the second wireless optical communication signal so that the second wireless optical communication signal is received by the first user equipment; Monitoring whether there is a first illegal monitoring device and a second illegal monitoring device, wherein the first illegal monitoring device is in the first communication space, and the second illegal monitoring device is in the second communication space; in the case of the presence of the first illegal monitoring device, controlling the first noise LED module to send a first preset interference signal, and controlling the Omni-DRIS module to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device; in the case of the presence of the second illegal monitoring device, controlling the first noise LED module to send the first preset interference signal to the second illegal monitoring device; The controlling the Omni-DRIS module to refract the first preset interference signal so that the first preset interference signal is received by the first illegal monitoring device includes: Acquire a second channel gain parameter and a second position information; wherein the second channel gain parameter is used to characterize the channel gain of the channel between the first LED array and the first illegal monitoring device, and the second position information is used to characterize the position of the first illegal monitoring device in the first communication space; The target direction of the first preset interference signal is determined according to the second channel gain parameter and the second position information, and the refraction angle of at least one control unit in the Omni-DR IS module is determined according to the target direction, so that the at least one control unit refracts the first preset interference signal to the first illegal monitoring device.

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