Optimization method and device for broadband transmission based on optical smart reflector

Abstract

The application relates to a wideband transmission optimization method and device of an optical intelligent reflecting surface, wherein the method comprises the following steps: calculating average multipath propagation delays of each user in a room; calculating a line-of-sight path channel gain and a reflection path channel gain of each user in the room; obtaining optimal optical intelligent reflecting surface parameters of each user in the room; and combining the optimal optical intelligent reflecting surface parameters and a multiple access mode to obtain a corresponding optimal multi-user signal transmission strategy. Thus, the problems in the prior art that the addition of an OIRS causes inter-symbol interference, uneven channel frequency, system performance deterioration, negative gain to users and the like are solved, the gain effect of the optical intelligent reflecting surface is improved, the energy loss of optical intelligent reflecting surface scheduling is reduced, and the channel capacity of a wireless optical broadband communication system is increased.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of intelligent reflection and visible light broadband communication, and particularly relates to a broadband transmission optimization method and device based on an optical intelligent reflecting surface. BACKGROUND

[0002] The sixth generation (6G) of future communication is envisaged as a powerful wireless network with global coverage, full spectrum use and intelligent communication features, which can provide ultra-high data rates for a large number of users and devices. VLC (Visible Light Communication) and LiFi (Light Fidelity) have a very rich spectrum range and can provide very high wireless transmission speed for users, and are therefore considered as key candidate technologies in 6G communication. VLC and LiFi also have many benefits in terms of communication security, data density and providing lighting functions. In traditional RF (Radio Frequency) communication, IRS (Intelligent Reflecting Surface) has been proven to be a technology that can effectively improve the performance of wireless communication systems, and has great potential in the fields of spectrum efficiency, multiple access and secure communication.

[0003] In related technologies, OIRS (Optical IRS) systems are used to assist various OWC (Optical Wireless Communication) systems to enhance received signal strength and avoid some line-of-sight path blocking problems.

[0004] However, in related technologies, the addition of OIRS causes inter-symbol interference, makes the channel frequency uneven, causes system performance degradation, has negative gain to users, and needs to be improved. SUMMARY

[0005] The present application provides a broadband transmission optimization method and device based on an optical intelligent reflecting surface to solve the problems in related technologies that the addition of OIRS causes inter-symbol interference, makes the channel frequency uneven, causes system performance degradation, has negative gain to users, improves the gain effect of the optical intelligent reflecting surface, reduces the energy loss of the optical intelligent reflecting surface scheduling, and increases the channel capacity of the wireless optical broadband communication system.

[0006] The first aspect of this application provides a broadband transmission optimization method based on an optical smart reflector, comprising the following steps: calculating the average multipath propagation delay of each user in a room using the location information of the transceiver and the optical smart reflector; calculating the line-of-sight path channel gain and the reflection path channel gain of each user in the room based on the location information of the transceiver and the optical smart reflector; obtaining the optimal optical smart reflector parameters of each user in the room based on the average multipath propagation delay, the line-of-sight path channel gain, and the reflection path channel gain, using preset optimization constraints and preset optimization objectives, combined with a multiple access method; and obtaining the corresponding optimal multi-user signal transmission strategy by combining the optimal optical smart reflector parameters and the multiple access method.

[0007] Optionally, in one embodiment of this application, the step of calculating the average multipath propagation delay of each user in the room using the position information of the transceiver and the optical intelligent reflective surface includes: calculating the line-of-sight path propagation delay from the transmitter to each user based on the channel state information of the line-of-sight path and the position information of the transmitter and receiver; calculating the transmission path propagation delay from the transmitter to the receiver after reflection by each unit of the optical intelligent reflective surface based on the channel state information of the reflection path and the position information of the transmitter, each unit of the optical intelligent reflective surface, and the receiver; grouping the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and calculating the average reflection path propagation delay of each group of reflective units.

[0008] Optionally, in one embodiment of this application, the step of grouping the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and calculating the average reflection path propagation delay of each group of reflective units, includes: grouping reflective surface units whose reflection path propagation delay reaches a preset proximity condition into the same group, such that the maximum propagation delay difference of each group of reflective units is less than or equal to the receiver sampling interval; calculating the average propagation delay of each group of reflective units as the reflection path propagation delay of each group of reflective units, wherein when the number of optical intelligent reflective surface units is less than a preset threshold and the reflection path propagation delay between units meets the preset condition, all reflective units are grouped into the same group.

[0009] Optionally, in one embodiment of this application, the step of calculating the line-of-sight path channel gain and reflection path channel gain of each user in the room based on the position information of the transceiver and the optical intelligent reflective surface includes: calculating the line-of-sight path channel gain of each user in the room by combining the position information of the transceiver and the line-of-sight path channel status information; calculating the reflection path channel gain provided by each reflection unit by combining the position information of the transceiver and the optical intelligent reflective surface, and calculating the total reflection path channel gain provided by each group of reflection units.

[0010] Optionally, in one embodiment of this application, the step of using preset optimization constraints and preset optimization objectives, combined with multiple access methods, to obtain the optimal optical smart reflective surface parameters for each user in the room based on the average multipath propagation delay, the line-of-sight path channel gain, and the reflection path channel gain includes: optimizing the parameters of the optical smart reflective surface using a preset optimization method based on the channel state information of the line-of-sight path and the smart surface reflection path, combined with the position information of the transmitter, the optical smart reflective surface, and the receiver, the preset optimization constraints and optimization objectives, and the multiple access methods, to obtain the optimal optical smart reflective surface parameters.

[0011] Optionally, in one embodiment of this application, the preset optimization objective includes at least one of minimizing the bit error rate of the wireless optical communication system, maximizing the channel capacity, and maximizing the minimum rate for multiple users.

[0012] Optionally, in one embodiment of this application, the preset optimization constraints include at least one of the following: non-negative real number constraints of the optical signal, total transmit power constraints, user service quality constraints, multi-user sum rate constraints, and single-user rate constraints.

[0013] Optionally, in one embodiment of this application, the multiple access method includes a non-orthogonal multiple access method or an orthogonal multiple access method; wherein, the non-orthogonal multiple access method includes at least one of power domain non-orthogonal multiple access method, code domain non-orthogonal multiple access method, and sparse coded multiple access method; the orthogonal multiple access method includes at least one of time domain orthogonal access method, frequency domain orthogonal access method, and orthogonal frequency division multiple access method.

[0014] Optionally, in one embodiment of this application, the broadband transmission optimization method based on the optical smart reflector further includes: adjusting the optimal optical smart reflector parameters based on the user's change instruction; and changing the smart surface reflection path signal of the wireless optical communication based on the adjusted optimal optical smart reflector parameters to change the total channel gain.

[0015] Optionally, in one embodiment of this application, the step of changing the smart surface reflection path signal of wireless optical communication based on the adjusted optimal optical smart reflective surface parameters to change the total channel gain includes: adjusting the orientation angle or control voltage of the reflection unit of the optical smart reflective surface; aligning the reflection unit with the corresponding LED (Light Emitting Diode) of the transmitter and the receiver, such that the reflection unit reflects the light beam emitted by the LED to the corresponding receiver, thereby adjusting the alignment relationship between the transmitter, the optical smart reflective surface and the receiver in the optical smart reflective surface parameters.

[0016] A second aspect of this application provides a broadband transmission optimization device based on an optical intelligent reflector, comprising: a first calculation module for calculating the average multipath propagation delay of each user in a room using the location information of a transceiver and the optical intelligent reflector; a second calculation module for calculating the line-of-sight path channel gain and the reflection path channel gain of each user in the room based on the location information of the transceiver and the optical intelligent reflector; an acquisition module for acquiring the optimal optical intelligent reflector parameters of each user in the room based on the average multipath propagation delay, the line-of-sight path channel gain, and the reflection path channel gain, using preset optimization constraints and preset optimization objectives, combined with a multiple access method; and an optimization module for obtaining a corresponding optimal multi-user signal transmission strategy by combining the optimal optical intelligent reflector parameters and the multiple access method.

[0017] Optionally, in one embodiment of this application, the first calculation module includes: a first calculation unit, used to calculate the line-of-sight path propagation delay from the transmitter to each user based on the channel state information of the line-of-sight path and the position information of the transmitter and receiver; a second calculation unit, used to calculate the transmission path propagation delay from the transmitter to the receiver after reflection by the optical intelligent reflective surface units based on the channel state information of the reflection path and the position information of the transmitter, each unit of the optical intelligent reflective surface, and the receiver; and a third calculation unit, used to group the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and calculate the average reflection path propagation delay of each group of reflective units.

[0018] Optionally, in one embodiment of this application, the third calculation unit includes: a grouping component, used to group the reflective surface units whose reflection path propagation delay reaches a preset proximity condition into the same group, such that the maximum propagation delay difference of each group of reflective units is less than or equal to the receiver sampling interval; and a calculation component, used to calculate the average propagation delay of each group of reflective units as the reflection path propagation delay of each group of reflective units, wherein when the number of optical intelligent reflective surface units is less than a preset threshold and the reflection path propagation delay between units meets the preset condition, all reflective units are grouped into the same group.

[0019] Optionally, in one embodiment of this application, the second calculation module includes: a fourth calculation unit, used to calculate the line-of-sight path channel gain of each user in the room by combining the position information of the transceiver and the line-of-sight path channel status information; and a fifth calculation unit, used to calculate the reflection path channel gain provided by each reflection unit by combining the position information of the transceiver and the optical intelligent reflective surface, and to calculate the total reflection path channel gain provided by each group of reflection units.

[0020] Optionally, in one embodiment of this application, the acquisition module includes: an acquisition unit, used to optimize the parameters of the optical intelligent reflective surface based on channel state information of the line-of-sight path and the intelligent surface reflection path, combined with the position information of the transmitter, the optical intelligent reflective surface and the receiver, the preset optimization constraints and optimization objectives, and the multiple access mode, using a preset optimization method to obtain the optimal optical intelligent reflective surface parameters.

[0021] Optionally, in one embodiment of this application, the preset optimization objective includes at least one of minimizing the bit error rate of the wireless optical communication system, maximizing the channel capacity, and maximizing the minimum rate for multiple users.

[0022] Optionally, in one embodiment of this application, the preset optimization constraints include at least one of the following: non-negative real number constraints of the optical signal, total transmit power constraints, user service quality constraints, multi-user sum rate constraints, and single-user rate constraints.

[0023] Optionally, in one embodiment of this application, the multiple access method includes a non-orthogonal multiple access method or an orthogonal multiple access method; wherein, the non-orthogonal multiple access method includes at least one of power domain non-orthogonal multiple access method, code domain non-orthogonal multiple access method, and sparse coded multiple access method; the orthogonal multiple access method includes at least one of time domain orthogonal access method, frequency domain orthogonal access method, and orthogonal frequency division multiple access method.

[0024] Optionally, in one embodiment of this application, the broadband transmission optimization device based on the optical smart reflective surface further includes: an adjustment module, configured to adjust the optimal optical smart reflective surface parameters based on a user's change instruction; and a change module, configured to change the smart surface reflection path signal of wireless optical communication based on the adjusted optimal optical smart reflective surface parameters, so as to change the total channel gain.

[0025] Optionally, in one embodiment of this application, the changing module includes: an adjustment unit for adjusting the orientation angle or control voltage of the reflective unit of the optical intelligent reflective surface; and an alignment unit for aligning the reflective unit with the corresponding LED of the transmitter and the receiver, so that the reflective unit reflects the light beam emitted by the LED to the corresponding receiver, thereby adjusting the alignment relationship between the transmitter, the optical intelligent reflective surface and the receiver in the parameters of the optical intelligent reflective surface.

[0026] A third aspect of this application provides an electronic device, including: 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 broadband transmission optimization method based on an optical smart reflective surface as described in the above embodiments.

[0027] A fourth aspect of this application provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the broadband transmission optimization method based on an optical smart reflective surface as described above.

[0028] This application's embodiments can obtain optimal optical intelligent reflective surface parameters based on the average multipath propagation delay of multiple users, the line-of-sight path channel gain, and the reflection path channel gain. Combined with multiple access methods, it obtains the corresponding optimal multi-user signal transmission strategy, improving the gain effect of the optical intelligent reflective surface, reducing the energy loss of optical intelligent reflective surface scheduling, and increasing the channel capacity of the wireless optical broadband communication system. Therefore, it solves the problems in related technologies where adding OIRS leads to inter-symbol interference, causing channel frequency unevenness, resulting in system performance degradation and negative gain for users. It improves the gain effect of the optical intelligent reflective surface, reduces the energy loss of optical intelligent reflective surface scheduling, and increases the channel capacity of the wireless optical broadband communication system.

[0029] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0030] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0031] Figure 1 This is a flowchart illustrating a broadband transmission optimization method based on an optical smart reflective surface, according to an embodiment of this application.

[0032] Figure 2 This is a schematic diagram illustrating the principle of a broadband transmission optimization method based on an optical smart reflective surface according to an embodiment of this application;

[0033] Figure 3 This is a signal processing block diagram of a broadband transmission optimization method based on an optical smart reflective surface according to an embodiment of this application;

[0034] Figure 4 This is a schematic diagram of a genetic algorithm for a broadband transmission optimization method based on an optical smart reflective surface according to an embodiment of this application;

[0035] Figure 5 This is a schematic diagram of a broadband transmission optimization device based on an optical intelligent reflective surface provided according to an embodiment of this application;

[0036] Figure 6 This is a schematic diagram of the structure of an electronic device provided according to an embodiment of this application. Detailed Implementation

[0037] The embodiments of this application are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0038] Before providing a detailed description of the broadband transmission optimization method and apparatus based on an optical intelligent reflective surface according to embodiments of the present invention, the relevant technologies will be specifically described first.

[0039] Specifically, the basic principle of IRS is to deploy multiple adjustable reflective units in the wireless propagation environment to reflect the incident signal to the target user. In this way, IRS can adaptively reconfigure the radio electromagnetic environment to change the wireless communication channel.

[0040] Most VLC systems use direct detection (DD) intensity modulation (IM) to transmit information. Because the detection area in VLC is very large relative to the wavelength of visible light, small-scale fading in VLC is typically small and often negligible in narrowband systems. Therefore, multiple optical signals received through different paths can be directly combined without strict phase control. This characteristic fundamentally distinguishes the OIRS in VLC from the IRS in RF systems. In IRS-assisted RF wireless systems, adjusting the reflection matrix to achieve optimal phase is crucial for maximizing gain. In OIRS-assisted VLC systems, controlling the reflection unit to reflect the optical signal towards the desired target direction is paramount.

[0041] In wideband VLC communication systems, the wide system bandwidth and short sampling intervals at the receiver lead to a significant difference in reflection delay between the line-of-sight (LoS) path and the reflection path. Therefore, the addition of OIRS (Optical Irregular Streams) can cause intersymbol interference (IMI), resulting in uneven channel frequency distribution within the VLC system and consequently degrading system performance. Furthermore, when the channel gain of the reflection path is smaller than that of the line-of-sight path, the IMI effect caused by OIRS may outweigh its signal enhancement effect. This means that OIRS may have a negative gain for users in certain locations within the room. Therefore, the allocation of OIRS in VLC wideband communication systems differs significantly from that in typical narrowband systems. In wideband systems, it is necessary to comprehensively consider system bandwidth, multipath propagation delay, transceiver location, and other factors to allocate OIRS appropriately and ensure that system performance is not degraded.

[0042] Based on the above problems, this invention proposes a broadband transmission optimization method and apparatus based on an optical intelligent reflective surface.

[0043] The following describes a broadband transmission optimization method and apparatus based on an optical intelligent reflector according to embodiments of this application, with reference to the accompanying drawings. Addressing the problem mentioned in the background section of the related technologies that the addition of an OIRS leads to inter-symbol interference, causing channel frequency unevenness, resulting in system performance degradation and negative gain for users, this application provides a broadband transmission optimization method based on an optical intelligent reflector. In this method, optimal optical intelligent reflector parameters can be obtained based on the average multipath propagation delay of multiple users, the line-of-sight path channel gain, and the reflection path channel gain. Furthermore, the optimal multi-user signal transmission strategy is obtained by combining the multiple access method, thereby improving the gain effect of the optical intelligent reflector, reducing the energy loss of optical intelligent reflector scheduling, and increasing the channel capacity of the wireless optical broadband communication system. Thus, this solves the problems in the related technologies where the addition of an OIRS leads to inter-symbol interference, causing channel frequency unevenness, resulting in system performance degradation and negative gain for users, improving the gain effect of the optical intelligent reflector, reducing the energy loss of optical intelligent reflector scheduling, and increasing the channel capacity of the wireless optical broadband communication system.

[0044] Specifically, Figure 1 This is a flowchart illustrating a broadband transmission optimization method based on an optical intelligent reflective surface, provided in an embodiment of this application.

[0045] like Figure 1 As shown, the broadband transmission optimization method based on an optical smart reflective surface includes the following steps:

[0046] In step S101, the average multipath propagation delay of each user in the room is calculated using the position information of the transceiver and the optical smart reflector.

[0047] In actual implementation, this embodiment of the application can assume that the positions of the transceiver and the optical intelligent reflector are fixed and known, and can be considered as fixed parameters pre-stored in the system controller. This embodiment of the application can also assume that the movement state of all users is quasi-static, that is, the user's position does not change significantly in a short period of time, and therefore can be considered fixed within the information transmission time slot. In particular, if the user's position changes significantly, it is necessary to reacquire the user's position information and then re-optimize the parameters of the optical intelligent reflector.

[0048] For example, embodiments of this application can utilize indoor positioning technologies such as WiFi (Wireless Fidelity, mobile hotspot) positioning technology or ZigBee positioning technology to obtain and update user location information. WiFi positioning technology can locate a user by utilizing the signal strength of the router at the receiving end, while ZigBee positioning technology can obtain user location information through a short-range wireless communication protocol. Those skilled in the art can choose the appropriate technology based on the actual situation, and no specific limitations are imposed here.

[0049] The calculation method for average multipath propagation delay will be explained in detail below.

[0050] Optionally, in one embodiment of this application, the average multipath propagation delay of each user in the room is calculated using the position information of the transceiver and the optical intelligent reflective surface, including: calculating the line-of-sight path propagation delay from the transmitter to each user based on the channel state information of the line-of-sight path and the position information of the transmitter and receiver; calculating the transmission path propagation delay from the transmitter to the receiver after reflection by each unit of the optical intelligent reflective surface based on the channel state information of the reflection path and the position information of the transmitter, each unit of the optical intelligent reflective surface and the receiver; grouping the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and calculating the average reflection path propagation delay of each group of reflection units.

[0051] Here, an example is given to illustrate the calculation method for average multipath propagation delay. In actual implementation, such as... Figure 2 The diagram shown illustrates the principle of a broadband transmission optimization method based on an optical smart reflective surface. It should be noted that in this embodiment, the number of transmitters can be one, the number of receivers can be multiple, and the number of units of the optical smart reflective surface can be one or more.

[0052] In this embodiment, K and W can represent the number of receivers and the total system bandwidth of the receivers, and N can represent the number of all smart reflective surface units in the room. In this embodiment, x can be used... L y L and z L The three-dimensional coordinates of the transmitter are represented by x(n), y(n), and z(n), respectively, and these coordinates remain unchanged during communication. In this application example, x(n), y(n), and z(n) can be used to represent the three-dimensional coordinates of the nth optical intelligent reflective surface unit. u (k), y u (k) and z u Let k) represent the latest 3D coordinates of the kth user, and update them after the user's position changes.

[0053] It is understood that, since the gains of diffuse reflection and multiple reflection paths in this embodiment are much smaller than the gains of line-of-sight paths and single specular reflection paths, they can be disregarded in this embodiment. Instead, only the line-of-sight path from the transmitter to the receiver and the reflection path to the receiver after one specular reflection by the smart reflector are considered.

[0054] Therefore, the line-of-sight path propagation delay from the transmitter to the k-th user in this application example can be:

[0055]

[0056] Where c represents the propagation speed of electromagnetic waves, x L y L and z L Let x and y represent the three-dimensional coordinates of the transmitter, respectively. u (k), y u (k) and z u (k) represents the latest three-dimensional coordinates of the k-th user.

[0057] The propagation delay from the transmitter to the k-th user after reflection by the nth optical intelligent reflector unit is:

[0058]

[0059] Where c represents the propagation speed of electromagnetic waves, x L y L and z L Let x and y represent the three-dimensional coordinates of the transmitter, respectively. u (k), y u (k) and z u (k) represents the latest three-dimensional coordinates of the k-th user, and x(n), y(n) and z(n) represent the three-dimensional coordinates of the n-th optical intelligent reflective surface unit.

[0060] Optionally, in one embodiment of this application, the optical intelligent reflective surface units are grouped based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and the average reflection path propagation delay of each group of reflective units is calculated. This includes: grouping reflective surface units whose reflection path propagation delay reaches a preset proximity condition into the same group, such that the maximum propagation delay difference of each group of reflective units is less than or equal to the receiver sampling interval; calculating the average propagation delay of each group of reflective units as the reflection path propagation delay of each group of reflective units, wherein when the number of optical intelligent reflective surface units is less than a preset threshold and the reflection path propagation delay between units meets the preset condition, all reflective units are grouped into the same group.

[0061] Specifically, in broadband communication, due to the short sampling time interval at the receiver, multipath propagation symbols may arrive at the receiver at different time intervals. Therefore, it is necessary to group the optical smart reflective surfaces so that the maximum propagation delay difference of the reflective surface units within each group is less than or equal to the receiver sampling interval. This application example can use a set N. i The number within the i-th optical intelligent reflective surface unit group is represented by a set. Given the receiver number, the reflecting elements within any smart reflective surface unit group should satisfy:

[0062]

[0063] Therefore, since the multipath propagation delay difference of the optical intelligent reflective surface units within each group cannot be distinguished within each sampling interval, the average propagation delay of the reflection path of all units within the group can be used to represent the propagation delay of the reflection path of each unit within the group.

[0064] In step S102, the line-of-sight path channel gain and reflection path channel gain of each user in the room are calculated based on the position information of the transceiver and the optical intelligent reflective surface.

[0065] For example, embodiments of this application can utilize channel estimation techniques to obtain channel state information for the line-of-sight path and the smart surface reflection path. The channel estimation technique can be based on a time-domain training sequence or a pilot sequence, such as least squares estimation or (linear) least mean square error estimation. Those skilled in the art can choose according to the actual situation, and no specific limitation is made here. Furthermore, channel estimation for the line-of-sight path can be performed with the optical smart reflective surface turned off; channel estimation for the smart surface reflection path can be performed by sequentially turning on each unit of the metasurface and estimating the channel response of the reflection path through each unit surface.

[0066] Optionally, in one embodiment of this application, calculating the line-of-sight path channel gain and reflection path channel gain for each user in the room based on the position information of the transceiver and the optical intelligent reflector includes: calculating the line-of-sight path channel gain for each user in the room by combining the position information of the transceiver and the line-of-sight path channel status information; calculating the reflection path channel gain provided by each reflection unit by combining the position information of the transceiver and the optical intelligent reflector, and calculating the total reflection path channel gain provided by each group of reflection units.

[0067] In actual implementation, the embodiments of this application can define the channel gain h of the line-of-sight path formed by the transmitter and receiver k based on the Lambertian radiation model. k Then the line-of-sight path channel gain h can be expressed as:

[0068]

[0069] In this embodiment, the channel gain of the smart surface reflection path, which is composed of smart reflective surface unit n and receiver k, can be defined as g. n,k The smart surface transmission path channel gain G can be expressed as:

[0070]

[0071] in

[0072] Specifically, embodiments of this application can utilize a binary correlation matrix between the transceiver and the various units of the smart reflective surface. This is an optical intelligent reflective surface matrix. The correlation matrix S has rows representing the number of intelligent reflective surface units and columns representing the number of receivers. A matrix element of "1" indicates a correlation between the intelligent reflective surface unit and its corresponding receiver; that is, the intelligent surface reflection path, consisting of the transmitter, intelligent reflective surface unit, and receiver, conforms to the generalized Snell's law, and the intelligent surface can reflect the signal from the transmitter to the designated receiver. A matrix element of "0" indicates that the intelligent reflective surface unit and its corresponding receiver are not aligned.

[0073] In step S103, using preset optimization constraints and preset optimization objectives, and combining multiple access methods, the optimal optical intelligent reflective surface parameters for each user in the room are obtained based on the average multipath propagation delay, line-of-sight path channel gain, and reflection path channel gain.

[0074] In actual implementation, the embodiments of this application can utilize preset optimization constraints and preset optimization objectives, combined with multiple access methods, to optimize the service relationship between optical intelligent reflective surface units and users based on average multipath propagation delay, line-of-sight path channel gain and reflection path channel gain. This allows the optimal optical intelligent reflective surface parameters for each user in the room to be obtained, enabling each user to receive services from zero or more optical intelligent reflective surface units, thereby providing reliable data support for the realization of wireless optical downlink broadband communication based on optical intelligent reflective surfaces.

[0075] The preset optimization constraints and preset optimization objectives will be explained in detail below.

[0076] Optionally, in one embodiment of this application, the optimal optical smart reflective surface parameters for each user in the room are obtained by utilizing preset optimization constraints and preset optimization objectives, combined with multiple access methods, based on average multipath propagation delay, line-of-sight path channel gain, and reflection path channel gain. This includes: optimizing the parameters of the optical smart reflective surface based on the channel state information of the line-of-sight path and the smart surface reflection path, combined with the position information of the transmitter, the optical smart reflective surface, and the receiver, the preset optimization constraints and optimization objectives, and the multiple access methods, using a preset optimization method to obtain the optimal optical smart reflective surface parameters.

[0077] Because the receiver sampling frequency is high in broadband communication systems, the propagation delay of the line-of-sight path and the reflection path causes symbol information transmitted from the transmitter to arrive at the receiver in different sampling time slots, resulting in inter-symbol interference (ISI). Therefore, the channel gains of the line-of-sight path and the reflection path cannot be directly added together. The following section will detail how to calculate the joint channel gain of a broadband transmission system based on an optical intelligent reflector.

[0078] For example, in embodiments of this application, the line-of-sight path channel gain for the k-th user can be defined as h. k The line-of-sight path propagation delay from the transmitter to the k-th user is... Assume the optical intelligent reflective surface unit serving the k-th user is a certain unit group N. i The average reflection path propagation delay of this group of intelligent reflection units is Then we can obtain the optical intelligent reflective surface unit group N. i The total reflection path channel gain provided is:

[0079]

[0080] In summary, the channel time-domain impulse response expression for the k-th user can be obtained as follows:

[0081]

[0082] Where δ(t) is the unit impulse response function. The corresponding channel frequency response expression can be obtained by performing a Fourier transform on the channel time-domain impulse response expression:

[0083]

[0084] Channel gain can be expressed as the square of the channel frequency response modulus, that is, the joint channel gain of the k-th user can be written in the following form:

[0085]

[0086] Where, Δτ k This represents the absolute value of the propagation delay difference between the line-of-sight path and the reflection path for the k-th user, i.e.:

[0087]

[0088] It should be noted that when multiple intelligent reflective surface unit groups serve the k-th user, the channel impulse response expression for the k-th user needs to be written in the following form because the propagation delay of the reflection path differs among each unit group:

[0089]

[0090] The joint channel gain expression calculated in this way is quite complex, but it can still be obtained by first performing a Fourier transform and then taking the square of the modulus, which will not be elaborated here.

[0091] Furthermore, embodiments of this application can use the total system channel capacity as the optimization objective. Since the Shannon formula cannot be directly used in visible light communication systems, the lower bound of the achievable rate of the VLC system can be used as the optimization objective. Because multipath delay in broadband communication systems causes the user's joint channel gain to be frequency-dependent, frequency integration is required when calculating the achievable rate.

[0092] Specifically, this application embodiment can take time-division multiple access as an example of multiple access mode, assuming that the transmission time slot duration of each user is equal. When the optical intelligent reflective surface unit serving the k-th user is a certain unit group N... i At that time, its achievable lower bound is:

[0093]

[0094] Among them, P T σ represents the transmission power of the transmitting end. 2 The power of the white Gaussian noise at the receiving end is represented by e, which is the base of the natural logarithm function.

[0095] When no optical intelligent reflective surface unit serves the k-th user, i.e., the k-th user only receives signals from the line-of-sight path, its achievable rate lower bound is:

[0096]

[0097] It should be noted that the multi-user reachable rate expression for visible light communication systems differs depending on the multiple access method. Researchers in this field can select the appropriate multiple access method based on the actual situation and calculate the allocation rate for a specific unit group N according to the corresponding reachable rate expression. i The reachable rate of the kth user before and after and R k .

[0098] It is worth noting that, in some cases, embodiments of this application may involve grouping a certain unit N. i After being allocated to the k-th user, the reachability rate of the k-th user actually decreased compared to before the allocation of the optical intelligent reflection unit, that is:

[0099]

[0100] However, when the number of units allocated within a reflective unit group is sufficiently large, allocating a smart reflective unit within the same group to the k-th user will result in a gain. Therefore, in a wireless downlink broadband communication system based on a smart optical reflective surface, for a given smart reflective unit group N... iIn this application embodiment, there are two allocation scenarios: all intelligent reflection units in the group are allocated to a certain user, or they are not allocated to any user.

[0101] The algorithms used in the embodiments of this application may include, but are not limited to, greedy algorithms, to obtain the optimal optical intelligent reflective surface parameters. For a certain intelligent reflective unit group N i In this embodiment of the application, a greedy algorithm can be used to allocate it to the user who can bring the maximum achievable rate gain. R represents the reachable rate of the k-th user before a certain unit group is allocated. k The achievable rate after assigning a certain unit group to the k-th user is represented by the intelligent reflection unit group N. i The users to be served should meet the following requirements:

[0102]

[0103] At the same time, the intelligent reflection unit group is assigned to user k * Then it also needs to meet the following requirements Otherwise, if allocating the smart reflective surface unit group to a user would only result in a negative gain, then this unit group will not be allocated to any user. Thus, the greedy algorithm can maximize the total reachable rate of the system while ensuring that allocating optical smart reflective surfaces does not degrade the system capacity. When the smart reflective units are not allocated to any user, the energy consumption required to schedule the smart reflective surface units can also be reduced to some extent.

[0104] The embodiments of this application can use a greedy algorithm to obtain the optical intelligent reflective surface parameters based on the estimated channel state information of the line-of-sight path and the reflection path, combined with the total system transmission bandwidth and the multipath propagation delay of different users, thereby achieving optimization of a specific target.

[0105] Optionally, in one embodiment of this application, the preset optimization objective includes at least one of minimizing the bit error rate of the wireless optical communication system, maximizing the channel capacity, and maximizing the minimum rate for multiple users.

[0106] Here, the preset optimization target is described as an example. The preset target of this application embodiment, i.e., the specific target, can be the minimum bit error rate of the wireless optical communication system, the maximum system capacity, or the maximum minimum rate of multiple users, etc., so as to optimize the optical intelligent reflective surface parameters by combining the preset optimization constraints and multiple access methods based on the channel gain, multipath propagation delay and preset target of each user.

[0107] Optionally, in one embodiment of this application, the preset optimization constraints include at least one of the following: non-negative real number constraints of the optical signal, total transmit power constraints, user service quality constraints, multi-user sum rate constraints, and single-user rate constraints.

[0108] Here, the preset optimization constraints are described in detail. As one possible implementation, in the embodiments of this application, when optimizing the optical intelligent reflective surface parameters, the line-of-sight path channel gain and the reflection path channel gain of each reflective unit can be obtained based on the channel state information. Then, a greedy algorithm is used to optimize the optical intelligent reflective surface parameters based on the multipath propagation delay and channel gain, thereby achieving the optimization of a specific target. Based on optimization constraints, such as the non-negative real number constraint of the optical signal, the total transmit power constraint, the user service quality constraint, the multi-user sum rate constraint, and the single-user rate constraint, the optical intelligent reflective surface parameters are optimized through optimization methods such as greedy algorithms and genetic algorithms.

[0109] Optionally, in one embodiment of this application, the multiple access method includes a non-orthogonal multiple access method or an orthogonal multiple access method; wherein, the non-orthogonal multiple access method includes at least one of power domain non-orthogonal multiple access method, code domain non-orthogonal multiple access method, and sparse coded multiple access method; the orthogonal multiple access method includes at least one of time domain orthogonal access method, frequency domain orthogonal access method, and orthogonal frequency division multiple access method.

[0110] In step S104, the optimal multi-user signal transmission strategy is obtained by combining the optimal optical intelligent reflective surface parameters and the multiple access method.

[0111] For example, in embodiments of this application, after optimizing a specific target by setting the parameters of the optical intelligent reflective surface matrix, a multi-user signal can be transmitted at the transmitting end according to the multi-user multiple access method.

[0112] When a non-orthogonal multiple access scheme is adopted, the multi-user coded sequences to be transmitted need to be weighted and summed according to the transmission power allocation coefficient to obtain the transmitter's transmission signal, thereby enabling the multi-user signals to be superimposed and transmitted at the transmitting end.

[0113] Specifically, embodiments of this application can use the signals x of K users k According to the power allocation factor α k By performing a weighted summation, we obtain the transmitted signal x from the transmitter:

[0114]

[0115] The transmit power allocation coefficient in the above formula must satisfy:

[0116]

[0117] When an orthogonal multiple access scheme is adopted, the transmitter can allocate corresponding time and frequency resources to multiple users according to the specific orthogonal multiple access method to realize orthogonal transmission of multi-user information.

[0118] Optionally, in one embodiment of this application, the broadband transmission optimization method based on the optical smart reflector further includes: adjusting the optimal optical smart reflector parameters based on the user's change instruction; and changing the smart surface reflection path signal of the wireless optical communication based on the adjusted optimal optical smart reflector parameters to change the total channel gain.

[0119] Specifically, after the transmitting end completes the encoding of the transmitted signal, the embodiments of this application can change the intelligent surface reflection path signal of wireless optical communication by setting the parameters of the optical intelligent reflective surface, thereby improving the system performance by actively changing the total channel gain.

[0120] In actual implementation, the embodiments of this application can utilize the optical intelligent reflective surface parameters to indicate the alignment relationship between the reflective surface unit and the receiver. Based on the optimized optical intelligent reflective surface parameters, the reflective unit and the corresponding receiver can be aligned by adjusting the orientation angle of the reflective unit or controlling the voltage, thereby realizing the change of the intelligent surface reflection path signal of wireless optical communication, and thus improving the system performance by actively changing the total channel gain.

[0121] Optionally, in one embodiment of this application, the intelligent surface reflection path signal of wireless optical communication is changed based on the adjusted optimal optical intelligent reflective surface parameters to change the total channel gain. This includes: adjusting the orientation angle or control voltage of the reflective unit of the optical intelligent reflective surface; aligning the reflective unit with the corresponding transmitter's LED and receiver, so that the reflective unit reflects the light beam emitted by the LED to the corresponding receiver, thereby adjusting the alignment relationship between the transmitter, the optical intelligent reflective surface, and the receiver in the optical intelligent reflective surface parameters.

[0122] It is understandable that the parameters of an optical intelligent reflective surface refer to the alignment relationship between the reflective surface unit and the receiver. The configuration parameters of each unit of the optical intelligent reflective surface are determined by its physical implementation method. The mirror array based on microelectromechanical system control can be realized by adjusting the orientation angle of each unit, while the intelligent reflective surface based on optical metamaterials can be realized by adjusting the control voltage of each unit of the reflective surface.

[0123] Specifically, embodiments of this application can change the smart surface reflection path signal of wireless optical communication by setting the parameters of the optical smart reflective surface, wherein the specific steps are as follows:

[0124] Step S1: Obtain the optical intelligent reflective surface matrix S according to the above optimization method, that is, obtain the alignment relationship between the intelligent reflective surface unit and the receiver;

[0125] Step S2: Adjust the parameters of each unit of the optical intelligent reflective surface according to the alignment relationship between the transmitter, reflective surface unit and receiver in the intelligent surface reflective optical path.

[0126] Among them, optical intelligent reflective surface matrix This represents the alignment relationship between the smart reflective surface and the receiver. The number of rows in the non-negative matrix S represents the number of smart reflective surface units, and the number of columns represents the number of receivers. When a matrix element is "1", it indicates that there is a correlation between the smart reflective surface unit and the corresponding receiver, meaning that the reflection path of the smart surface, consisting of the transmitter, smart reflective surface unit, and receiver, conforms to the generalized Snell's law, and the emitted light beam can be reflected by the smart surface to the designated receiver; otherwise, it indicates that there is no correlation, meaning that the smart reflective surface unit and the corresponding transceiver are not aligned.

[0127] Furthermore, embodiments of this application can align the reflective unit and the corresponding receiver using a codebook lookup method or a geometric calculation method based on optimized optical intelligent reflective surface parameters.

[0128] The configuration of reflective surface parameters based on the defined smart reflective surface matrix depends on the alignment of the reflected optical path, including the alignment of the smart reflective surface unit and the transmitter, as well as the alignment with the receiver. In the embodiments of this application, the reflected optical path alignment can be performed using the following alignment method:

[0129] (1) Codebook lookup method: For a selected receiver and optical intelligent reflective surface unit, the projection position of the intelligent surface reflection path signal on the user plane can be changed by adjusting the configuration parameters of the optical intelligent reflective surface. In each implementation, the projection position and configuration parameters are combined as a codeword in the codebook. In a typical indoor wireless optical communication scenario, since the positions of the receiver and the optical intelligent reflective surface remain fixed for a short period of time, the codebook is generated once before each change in the receiver position, which has low complexity.

[0130] It should be noted that in the codebook lookup method, the codebook only needs to be generated once when the receiver position remains unchanged. Therefore, it has lower complexity and can meet the dynamic requirements of the system.

[0131] (2) Geometric calculation method: When the positions of the receiver and the optical intelligent reflective surface are fixed and known, the required orientation of the intelligent reflective surface unit can be calculated according to the generalized Snell's law in the embodiments of this application.

[0132] The method for aligning the reflected light path can be selected by those skilled in the art based on the actual situation, and no specific restrictions are imposed here.

[0133] Combination Figures 2 to 4 As shown, the working principle of the broadband transmission optimization method based on optical intelligent reflective surface of this application is explained in detail with multiple embodiments.

[0134] In multiple-input single-output wireless optical communication systems, such as Figure 2 As shown, the optical intelligent reflective surface is realized based on a mirror array controlled by a microelectromechanical system. The broadband transmission optimization method based on the optical intelligent reflective surface in this application embodiment can be implemented using time division multiple access.

[0135] In multiple-input single-output wireless optical communication systems, such as Figure 2 As shown, the number of transmitters is 1, the number of receivers is K, the number of smart reflective surface units is N, the total system bandwidth is W, and the optimization objective function is system capacity. When frequency division multiple access is used as the multiple access method, the method may include the following steps:

[0136] S1: Using preset optimization constraints and preset optimization objectives, the optimal optical intelligent reflective surface parameters for each user in the room are obtained based on the difference between channel gain and average multipath propagation delay.

[0137] When the multiple access method uses frequency division multiple access (FDMA), the total system bandwidth is divided into K sub-channels, and the frequency domain resources of each sub-channel are used to transmit symbol information for a specific user. In this embodiment, it is assumed that the sub-channels are uniformly divided, meaning that each sub-channel has equal bandwidth. Assume the sub-channel frequency range occupied by the k-th user is from W k To (W) k With +B), we can obtain the expression for the lower bound of the achievable rate of the k-th user when only the line-of-sight path channel gain is considered:

[0138]

[0139] When the optical intelligent reflective surface unit serving the k-th user is a certain unit group N i At that time, its achievable lower bound is:

[0140]

[0141] Based on the above results, embodiments of this application can use sorting-based genetic algorithms and greedy algorithms to optimize the allocation relationship between users and sub-channels and the parameters of the optical intelligent reflective surface.

[0142] like Figure 4The diagram shows a schematic of the genetic algorithm for the broadband transmission optimization method based on an optical intelligent reflector, according to an embodiment of this application. Each individual in the genetic algorithm population is a permutation of K user indices, with each user using a sub-channel. During crossover, a segment from one of two chromosomes is randomly selected as the offspring chromosome, and the remaining users are sequentially filled from the other chromosome to generate new individuals. During mutation, two points on the chromosome are randomly selected and swapped. During selection, all intelligent reflector units N are greedily allocated. i .remember R represents the reachable rate of the k-th user before a certain unit group is allocated. k The achievable rate after assigning a certain unit group to the k-th user is represented by the intelligent reflection unit group N. i The users to be served should meet the following requirements:

[0143]

[0144] And assign the intelligent reflection unit group to user k * Then it also needs to meet the following requirements Otherwise, this unit group will not be allocated. All intelligent reflection unit groups N are allocated according to the greedy strategy described above. i Then, the total system channel capacity represented by each individual is calculated, and individuals with larger total system channel capacity are selected to be retained for the next generation. After multiple iterations, an optimal user-subchannel allocation relationship and the connection relationship between the optical intelligent reflective surface unit and the user can be obtained, thereby completing the optimization of the optical intelligent reflective surface parameters.

[0145] S2: Combining optimal optical intelligent reflective surface parameters and multiple access methods, signals from multiple users are transmitted at the transmitting end using the frequency division multiple access method.

[0146] In this embodiment, after optimizing the sub-channel and user allocation relationship and the optical intelligent reflective surface parameters using a genetic algorithm, the optical intelligent reflective surface parameters are first adjusted based on user change commands. Based on these parameters, the intelligent surface reflection path signal for wireless optical communication is altered to change the overall channel gain. Then, based on the sub-channel and user allocation relationship, the transmitter orthogonally transmits multi-user symbol information according to each user's frequency domain resources.

[0147] In multiple-input single-output wireless optical communication systems, such as Figure 2 As shown, the number of transmitters is 1, the number of receivers is K, the number of smart reflective surface units is N, the total system bandwidth is W, and the optimization objective function is the system capacity. When the multiple access method adopts power domain non-orthogonal multiple access, the method may include the following steps:

[0148] S1: Using preset optimization constraints and preset optimization objectives, the optimal optical intelligent reflective surface parameters of each user in the room are obtained based on channel gain and average multipath propagation delay.

[0149] When the multiple access method is power-domain non-orthogonal multiple access, multiple users share the total system bandwidth W, and encoding and demodulation are performed through superposition coding and serial interference cancellation. In the embodiments of this application, the user's transmit power allocation coefficient can be determined by the line-of-sight path channel gain, that is, users with higher line-of-sight path channel gain are allocated less transmit power. Figure 3 As shown, in this embodiment, serial interference cancellation technology can be used at the receiving end to demodulate according to signal power strength, that is, users with larger transmit power allocation coefficients are demodulated first. In this embodiment, it can be assumed that users are ordered according to the line-of-sight path channel gain, satisfying: h1≥h2≥…≥h K Then the transmission power should satisfy: α1≤α2≤…≤α K And α1+α2+…+α K =1.

[0150] It should be noted that the transmit power allocation coefficient can be obtained using methods such as convex optimization, GRPA, and fixed coefficients. Those skilled in the art can choose according to the actual situation, and no specific restrictions are imposed here.

[0151] Specifically, in the embodiments of this application, it is assumed that the serial interference cancellation process is ideal, that is, the user information demodulated first can be completely removed. Based on the above results, the expression for the multi-user reachable rate when only the line-of-sight path channel gain is considered can be obtained:

[0152]

[0153]

[0154] When a certain optical intelligent reflective surface unit group N i When serving a user, its achievable rate lower bound is:

[0155]

[0156]

[0157] Based on the above results, the embodiments of this application can use a greedy algorithm to optimize the parameters of the optical intelligent reflective surface.

[0158] remember R represents the reachable rate of the k-th user before a certain unit group is allocated. k The achievable rate after assigning a certain unit group to the k-th user is represented by the intelligent reflection unit group N.i The users to be served should meet the following requirements:

[0159]

[0160] At the same time, the intelligent reflection unit group is assigned to user k * Then it also needs to meet the following requirements Otherwise, this unit group will not be assigned to any user. All intelligent reflection unit groups N will be assigned according to the greedy strategy described above. i Then, the connection matrix s between all optical intelligent reflective surface units and users can be obtained, thereby completing the optimization of the optical intelligent reflective surface parameters.

[0161] In particular, if the total channel quality ranking of each user differs from the line-of-sight path channel quality ranking after the optical intelligent reflective surface parameters are optimized, then each user needs to be renumbered according to the total channel quality ranking, and then the aforementioned optimization process is repeated to complete the optimization of the optical intelligent reflective surface and the transmit power allocation coefficient.

[0162] Based on the above criteria, the embodiments of this application can optimize the parameters of the optical intelligent reflective surface using a greedy algorithm.

[0163] S2: Combining optimal optical intelligent reflective surface parameters and multiple access methods, signals from multiple users are transmitted at the transmitting end using a power domain non-orthogonal multiple access method.

[0164] In actual implementation, the embodiments of this application can first adjust the optical intelligent reflective surface parameters based on the user's change instructions after optimizing the optical intelligent reflective surface parameters using a greedy algorithm; and then change the intelligent surface reflection path signal of wireless optical communication based on the optical intelligent reflective surface parameters to change the total channel gain.

[0165] Then the multi-user signal x k According to the transmit power allocation coefficient α respectively k By performing a weighted summation, we obtain the transmitted signal x from the transmitter:

[0166]

[0167] The transmitted signal is then mapped and modulated, and sent to the receiving end via the channel.

[0168] The broadband transmission optimization method based on optical intelligent reflectors proposed in this application can obtain the optimal optical intelligent reflector parameters based on the average multipath propagation delay of multiple users, the line-of-sight path channel gain, and the reflection path channel gain. Combined with multiple access methods, it obtains the corresponding optimal multi-user signal transmission strategy, thereby improving the gain effect of the optical intelligent reflector, reducing the energy loss of optical intelligent reflector scheduling, and increasing the channel capacity of the wireless optical broadband communication system. This solves the problems in related technologies, such as inter-symbol interference caused by adding OIRS, resulting in channel frequency unevenness, degrading system performance, and negative gain for users. It improves the gain effect of the optical intelligent reflector, reduces the energy loss of optical intelligent reflector scheduling, and increases the channel capacity of the wireless optical broadband communication system.

[0169] Next, with reference to the accompanying drawings, a broadband transmission optimization device based on an optical intelligent reflective surface, according to an embodiment of this application, is described.

[0170] Figure 5 This is a block diagram of a broadband transmission optimization device based on an optical intelligent reflective surface according to an embodiment of this application.

[0171] like Figure 5 As shown, the broadband transmission optimization device 10 based on an optical intelligent reflective surface includes: a first calculation module 100, a second calculation module 200, an acquisition module 300, and an optimization module 400.

[0172] The first calculation module 100 is used to calculate the average multipath propagation delay of each user in the room using the position information of the transceiver and the optical smart reflective surface.

[0173] The second calculation module 200 is used to calculate the line-of-sight path channel gain and reflection path channel gain of each user in the room based on the position information of the transceiver and the optical intelligent reflective surface.

[0174] The acquisition module 300 is used to acquire the optimal optical intelligent reflective surface parameters of each user in the room by using preset optimization constraints and preset optimization objectives, combined with multiple access methods, based on average multipath propagation delay, line-of-sight path channel gain and reflection path channel gain.

[0175] The optimization module 400 is used to combine the optimal optical intelligent reflective surface parameters and the multiple access method to obtain the corresponding optimal multi-user signal transmission strategy.

[0176] Optionally, in one embodiment of this application, the first computing module 100 includes: a first computing unit, a second computing unit, and a third computing unit.

[0177] The first calculation unit is used to calculate the line-of-sight path propagation delay from the transmitter to each user based on the channel state information of the line-of-sight path and the location information of the transmitter and receiver.

[0178] The second calculation unit is used to calculate the transmission path propagation delay from the transmitter to the receiver after reflection by each unit of the optical intelligent reflective surface, based on the channel state information of the reflection path and the position information of the transmitter, each unit of the optical intelligent reflective surface and the receiver.

[0179] The third calculation unit is used to group the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and to calculate the average reflection path propagation delay of each group of reflective units.

[0180] Optionally, in one embodiment of this application, the third computing unit includes a grouping component and a computing component.

[0181] The grouping component is used to group reflective surface units whose propagation delay on the reflection path reaches a preset proximity condition into the same group, so that the maximum propagation delay difference of each group of reflective units is less than or equal to the receiver sampling interval.

[0182] The calculation component is used to calculate the average propagation delay of each group of reflective units, which is used as the propagation delay of the reflection path of each group of reflective units. When the number of optical intelligent reflective surface units is less than a preset threshold and the propagation delay of the reflection path between units meets the preset conditions, all reflective units are divided into the same group.

[0183] Optionally, in one embodiment of this application, the second computing module 200 includes a fourth computing unit and a fifth computing unit.

[0184] The fourth calculation unit is used to calculate the line-of-sight path channel gain of each user in the room by combining the transceiver's location information and the line-of-sight path channel status information.

[0185] The fifth calculation unit is used to combine the position information of the transceiver and the optical intelligent reflector to calculate the reflection path channel gain provided by each reflection unit, and to calculate the total reflection path channel gain provided by each group of reflection units.

[0186] Optionally, in one embodiment of this application, the acquisition module 300 includes: an acquisition unit.

[0187] The acquisition unit is used to optimize the parameters of the optical intelligent reflective surface based on the channel state information of the line-of-sight path and the intelligent surface reflection path, combined with the position information of the transmitter, the optical intelligent reflective surface and the receiver, the preset optimization constraints and optimization objectives, and the multiple access mode, using a preset optimization method to obtain the optimal optical intelligent reflective surface parameters.

[0188] Optionally, in one embodiment of this application, the preset optimization objective includes at least one of minimizing the bit error rate of the wireless optical communication system, maximizing the channel capacity, and maximizing the minimum rate for multiple users.

[0189] Optionally, in one embodiment of this application, the preset optimization constraints include at least one of the following: non-negative real number constraints of the optical signal, total transmit power constraints, user service quality constraints, multi-user sum rate constraints, and single-user rate constraints.

[0190] Optionally, in one embodiment of this application, the multiple access method includes a non-orthogonal multiple access method or an orthogonal multiple access method; wherein, the non-orthogonal multiple access method includes at least one of power domain non-orthogonal multiple access method, code domain non-orthogonal multiple access method, and sparse coded multiple access method; the orthogonal multiple access method includes at least one of time domain orthogonal access method, frequency domain orthogonal access method, and orthogonal frequency division multiple access method.

[0191] Optionally, in one embodiment of this application, the broadband transmission optimization device 10 based on an optical smart reflective surface further includes an adjustment module and a change module.

[0192] The adjustment module is used to adjust the optimal optical intelligent reflective surface parameters based on the user's change instructions.

[0193] The module is used to change the smart surface reflection path signal of wireless optical communication based on the adjusted optimal optical smart reflective surface parameters, thereby changing the total channel gain.

[0194] Optionally, in one embodiment of this application, the changing module includes an adjustment unit and an alignment unit.

[0195] The adjustment unit is used to adjust the orientation angle of the reflective unit of the optical intelligent reflective surface or to control the voltage.

[0196] An alignment unit is used to align the reflection unit with the corresponding LED of the transmitter and the receiver, so that the reflection unit reflects the light beam emitted by the LED to the corresponding receiver, thereby adjusting the alignment relationship between the transmitter, the optical intelligent reflective surface and the receiver in the optical intelligent reflective surface parameters.

[0197] It should be noted that the foregoing explanation of the broadband transmission optimization method based on optical intelligent reflective surface also applies to the broadband transmission optimization device based on optical intelligent reflective surface in this embodiment, and will not be repeated here.

[0198] The broadband transmission optimization device based on an optical intelligent reflector proposed in this application can obtain the optimal optical intelligent reflector parameters based on the average multipath propagation delay of multiple users, the line-of-sight path channel gain, and the reflection path channel gain. Combined with the multiple access method, it obtains the corresponding optimal multi-user signal transmission strategy, thereby improving the gain effect of the optical intelligent reflector, reducing the energy loss of optical intelligent reflector scheduling, and increasing the channel capacity of the wireless optical broadband communication system. This solves the problems in related technologies, such as inter-symbol interference caused by adding an OIRS, resulting in channel frequency unevenness, deteriorating system performance, and negative gain for users. It improves the gain effect of the optical intelligent reflector, reduces the energy loss of optical intelligent reflector scheduling, and increases the channel capacity of the wireless optical broadband communication system.

[0199] Figure 6 A schematic diagram of the structure of an electronic device provided in an embodiment of this application. The electronic device may include:

[0200] The memory 601, the processor 602, and the computer program stored on the memory 601 and capable of running on the processor 602.

[0201] When the processor 602 executes the program, it implements the broadband transmission optimization method based on the optical intelligent reflective surface provided in the above embodiments.

[0202] Furthermore, electronic devices also include:

[0203] Communication interface 603 is used for communication between memory 601 and processor 602.

[0204] The memory 601 is used to store computer programs that can run on the processor 602.

[0205] The memory 601 may include high-speed RAM memory, and may also include non-volatile memory, such as at least one disk storage device.

[0206] If the memory 601, processor 602, and communication interface 603 are implemented independently, then the communication interface 603, memory 601, and processor 602 can be interconnected via a bus to complete communication between them. The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of representation, Figure 6 The bus is represented by a single thick line, but this does not mean that there is only one bus or one type of bus.

[0207] Optionally, in a specific implementation, if the memory 601, processor 602, and communication interface 603 are integrated on a single chip, then the memory 601, processor 602, and communication interface 603 can communicate with each other through an internal interface.

[0208] The processor 602 may be a central processing unit (CPU), an application specific integrated circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of this application.

[0209] This application also provides a computer-readable storage medium storing a computer program thereon, which, when executed by a processor, implements the above-described broadband transmission optimization method based on an optical smart reflective surface.

[0210] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0211] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this application, "N" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0212] Any process or method described in the flowchart or otherwise herein can be understood as representing a module, segment, or portion of code comprising one or N executable instructions for implementing custom logic functions or processes, and the scope of the preferred embodiments of this application includes additional implementations in which functions may be performed not in the order shown or discussed, including substantially simultaneously or in reverse order depending on the functions involved, as should be understood by those skilled in the art to which embodiments of this application pertain.

[0213] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a sequenced list of executable instructions for implementing logical functions, and can be embodied in any computer-readable medium for use by, or in conjunction with, an instruction execution system, apparatus, or device (such as a computer-based system, a processor-included system, or other system that can fetch and execute instructions from, an instruction execution system, apparatus, or device). For the purposes of this specification, "computer-readable medium" can be any means that can contain, store, communicate, propagate, or transmit programs for use by, or in conjunction with, an instruction execution system, apparatus, or device. More specific examples (a non-exhaustive list) of computer-readable media include: an electrical connection having one or more wires (electronic device), a portable computer disk drive (magnetic device), random access memory (RAM), read-only memory (ROM), erasable and editable read-only memory (EPROM or flash memory), fiber optic devices, and portable optical disc read-only memory (CDROM). Alternatively, the computer-readable medium may be paper or other suitable media on which the program can be printed, since the program can be obtained electronically by optically scanning the paper or other medium, followed by editing, interpreting, or otherwise processing as necessary, and then stored in a computer memory.

[0214] It should be understood that the various parts of this application can be implemented using hardware, software, firmware, or a combination thereof. In the above embodiments, the N steps or methods can be implemented using software or firmware stored in memory and executed by a suitable instruction execution system. If implemented in hardware, as in another embodiment, it can be implemented using any one or a combination of the following techniques known in the art: discrete logic circuits having logic gates for implementing logical functions on data signals, application-specific integrated circuits (ASICs) having suitable combinational logic gates, programmable gate arrays (PGAs), field-programmable gate arrays (FPGAs), etc.

[0215] Those skilled in the art will understand that all or part of the steps of the methods in the above embodiments can be implemented by a program instructing related hardware. The program can be stored in a computer-readable storage medium, and when executed, the program includes one or a combination of the steps of the method embodiments.

[0216] Furthermore, the functional units in the various embodiments of this application can be integrated into a processing module, or each unit can exist physically separately, or two or more units can be integrated into a module. The integrated module can be implemented in hardware or as a software functional module. If the integrated module is implemented as a software functional module and sold or used as an independent product, it can also be stored in a computer-readable storage medium.

[0217] The storage medium mentioned above can be a read-only memory, a disk, or an optical disk, etc. Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of this application.

Claims

1. A broadband transmission optimization method based on an optical intelligent reflective surface, characterized in that, Includes the following steps: The average multipath propagation delay of each user in the room is calculated using the position information of the transceiver and the optical intelligent reflective surface. Based on the position information of the transceiver and the optical intelligent reflective surface, calculate the line-of-sight path channel gain and the reflection path channel gain for each user in the room; By utilizing preset optimization constraints and preset optimization objectives, and combining multiple access methods, the optimal optical intelligent reflective surface parameters for each user in the room are obtained based on the average multipath propagation delay, the line-of-sight path channel gain, and the reflection path channel gain. as well as By combining the optimal optical intelligent reflective surface parameters and the multiple access method, the corresponding optimal multi-user signal transmission strategy is obtained.

2. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1, characterized in that, The calculation of the average multipath propagation delay for each user in the room using the position information of the transceiver and the optical intelligent reflector includes: Based on the channel state information of the line-of-sight path, combined with the location information of the transmitter and receiver, the line-of-sight path propagation delay from the transmitter to each user is calculated; Based on the channel state information of the reflection path, combined with the position information of the transmitter, each unit of the optical intelligent reflective surface, and the receiver, the propagation delay of the reflection path from the transmitter to the receiver after reflection by each unit of the optical intelligent reflective surface is calculated. Based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, the optical intelligent reflective surface units are grouped, and the average reflection path propagation delay of each group of reflective units is calculated.

3. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 2, characterized in that, The process of grouping the optical intelligent reflective surface units based on the system transmission bandwidth and the reflection path propagation delay of each unit of the optical intelligent reflective surface, and calculating the average reflection path propagation delay of each group of reflective units, includes: The reflective surface units whose propagation delay of the reflection path reaches the preset proximity condition are divided into the same group, such that the maximum propagation delay difference of each group of reflective units is less than or equal to the receiver sampling interval. The average propagation delay of each group of reflective units is calculated as the propagation delay of the reflection path of each group of reflective units. When the number of optical intelligent reflective surface units is less than a preset threshold and the propagation delay of the reflection path between units meets the preset condition, all reflective units are divided into the same group.

4. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 2 or 3, characterized in that, The calculation of the line-of-sight path channel gain and reflection path channel gain for each user in the room based on the position information of the transceiver and the optical intelligent reflector includes: Based on the transceiver's location information and line-of-sight path channel status information, calculate the line-of-sight path channel gain for each user in the room; Based on the position information of the transceiver and the optical intelligent reflective surface, the reflection path channel gain provided by each reflection unit is calculated, and the total reflection path channel gain provided by each group of reflection units is calculated.

5. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1, characterized in that, The process of obtaining the optimal optical intelligent reflective surface parameters for each user in the room based on the average multipath propagation delay, the line-of-sight path channel gain, and the reflection path channel gain, using preset optimization constraints and preset optimization objectives, combined with multiple access methods, includes: Based on the channel state information of the line-of-sight path and the intelligent surface reflection path, combined with the position information of the transmitter, the optical intelligent reflective surface and the receiver, the preset optimization constraints and optimization objectives, and the multiple access method, the parameters of the optical intelligent reflective surface are optimized using a preset optimization method to obtain the optimal optical intelligent reflective surface parameters.

6. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1 or 5, characterized in that, The preset optimization objectives include at least one of the following: minimizing the bit error rate of the wireless optical communication system, maximizing the channel capacity, and maximizing the minimum rate for multiple users.

7. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1 or 5, characterized in that, The preset optimization constraints include at least one of the following: non-negative real number constraints of optical signals, total transmit power constraints, user service quality constraints, multi-user rate constraints, and single-user rate constraints.

8. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1 or 5, characterized in that, The multiple access method includes a non-orthogonal multiple access method or an orthogonal multiple access method; wherein, the non-orthogonal multiple access method includes at least one of power domain non-orthogonal multiple access method, code domain non-orthogonal multiple access method, and sparse coded multiple access method; the orthogonal multiple access method includes at least one of time domain orthogonal access method, frequency domain orthogonal access method, and orthogonal frequency division multiple access method.

9. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 1, characterized in that, Also includes: Based on the user's change instructions, the parameters of the optimal optical intelligent reflective surface are adjusted; The intelligent surface reflection path signal of wireless optical communication is changed based on the adjusted optimal optical intelligent reflective surface parameters to alter the total channel gain.

10. The broadband transmission optimization method based on an optical intelligent reflective surface according to claim 9, characterized in that, The method of altering the smart surface reflection path signal of wireless optical communication based on the adjusted optimal optical smart reflective surface parameters to change the total channel gain includes: Adjusting the orientation angle of the reflective unit of the optical intelligent reflective surface or controlling the voltage; Align the reflective unit with the corresponding LED of the transmitter and the receiver, so that the reflective unit reflects the light beam emitted by the LED to the corresponding receiver, in order to adjust the alignment relationship between the transmitter, the optical intelligent reflective surface and the receiver in the optical intelligent reflective surface parameters.

11. A broadband transmission optimization device based on an optical intelligent reflective surface, characterized in that, include: The first calculation module is used to calculate the average multipath propagation delay of each user in the room using the position information of the transceiver and the optical smart reflective surface. The second calculation module is used to calculate the line-of-sight path channel gain and reflection path channel gain of each user in the room based on the position information of the transceiver and the optical intelligent reflective surface. The acquisition module is used to obtain the optimal optical intelligent reflective surface parameters of each user in the room by using preset optimization constraints and preset optimization objectives, combined with multiple access methods, based on average multipath propagation delay, line-of-sight path channel gain and reflection path channel gain. The optimization module is used to combine the optimal optical intelligent reflective surface parameters and multiple access methods to obtain the corresponding optimal multi-user signal transmission strategy.

12. An electronic device, characterized in that, include: A memory, a processor, and a computer program stored in the memory and executable on the processor, the processor executing the program to implement the broadband transmission optimization method based on an optical smart reflective surface as described in any one of claims 1-10.

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

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