A multi-time-scale intelligent metasurface configuration method adapted to transmission scheme

Abstract

The present invention discloses a multi-time-scale intelligent metasurface configuration method for an adaptive transmission scheme, comprising: a base station determines a wireless transmission scheme to be adopted according to wireless transmission performance requirements; for the adopted wireless transmission scheme, the base station analyzes channel characteristics suitable for the wireless transmission scheme; according to the required channel characteristics, the base station analyzes and determines an intelligent metasurface configuration method for realizing the channel characteristics and required channel state information; the base station performs channel estimation to obtain the channel state information required for the intelligent metasurface configuration method; the base station configures an intelligent metasurface on a corresponding time scale using the obtained channel state information to form a channel suitable for the adopted wireless transmission scheme; the base station and a user terminal design the adopted wireless transmission scheme according to the channel formed by the intelligent metasurface configuration, and perform data transmission. The present invention can improve the transmission performance and design freedom of a wireless communication system by configuring an intelligent metasurface to form a channel adapted to the transmission scheme.

Description

Technical Field

[0001] The present invention provides a multi-time scale intelligent metasurface configuration method for an adaptive transmission scheme, belonging to the technical field of wireless communications. Background Art

[0002] MIMO (multiple-input multiple-output) technology is one of the key technologies in the field of wireless communications. It can achieve different wireless transmission performance improvements under different transmission scheme designs. For example, the wireless transmission rate can be improved through the spatial multiplexing transmission scheme, and the wireless transmission reliability can be enhanced through the spatial diversity transmission scheme. Generally speaking, the performance of the transmission scheme depends on the characteristics of the channel. In traditional wireless communication systems, the channel is regarded as an uncontrollable factor. Therefore, the transmission scheme can only be passively designed adaptively according to the changes in the channel, which greatly limits the design of the transmission scheme. The emergence of intelligent metasurfaces with the ability to change electromagnetic waves in space makes it possible to control the channel.

[0003] A smart metasurface is a two-dimensional electromagnetic plane composed of adjustable metamaterial units. By controlling the adjustable metamaterial units, the smart metasurface can change the amplitude, phase, frequency, and polarization direction of the incident electromagnetic wave. Introducing smart metasurfaces into wireless communication systems will expand the traditional two-node (i.e., transmitter and receiver) wireless communication to three-node (i.e., transmitter, smart metasurface, and receiver). Through the joint design of the transmitter, smart metasurface, and receiver, the performance of the wireless communication system will be greatly improved. Current research on the joint design of transmitters, smart metasurfaces, and receivers often summarizes the design scheme as a mathematical optimization problem, and obtains the solution of the optimization problem through a series of complex optimization algorithms. This type of mathematical optimization method often has high computational complexity and does not pay attention to the actual effect of the smart metasurface on the channel. In addition, most of the current work on the application of smart metasurfaces to wireless communications only considers the configuration of the smart metasurface in a single time dimension, ignoring that the smart metasurface can be configured at different time scales to change the channel. Summary of the invention

[0004] Technical problem: In order to overcome the problem that existing transmission schemes are limited by channels, the present invention provides a multi-time-scale intelligent metasurface configuration method that is adapted to the transmission scheme. Through flexible multi-time-scale intelligent metasurface configuration, a suitable channel is customized for the transmission scheme to give full play to the performance of the transmission scheme.

[0005] Technical solution: To achieve the above-mentioned invention object, a multi-time scale intelligent metasurface configuration method of the present invention that adapts the transmission scheme adopts the following steps:

[0006] Step 1: The base station determines the wireless transmission scheme to be adopted according to the wireless transmission performance requirements;

[0007] Step 2: For the adopted wireless transmission scheme, the base station analyzes the channel characteristics suitable for the wireless transmission scheme;

[0008] Step 3: Based on the required channel characteristics, the base station analyzes and determines the intelligent metasurface configuration method and the required channel state information to achieve the channel characteristics;

[0009] Step 4: The base station performs channel estimation to obtain the channel state information required by the intelligent metasurface configuration method;

[0010] Step 5: The base station uses the acquired channel state information to configure the smart metasurface on the corresponding time scale to form a channel suitable for the adopted wireless transmission scheme;

[0011] Step 6: The base station and the user terminal perform data transmission according to the wireless transmission scheme adopted by the channel design formed by the intelligent metasurface configuration.

[0012] According to the performance requirement of improving the wireless transmission rate, the base station adopts a spatial multiplexing transmission scheme in the interference-limited area and a beamforming transmission scheme in the noise-limited area; according to the performance requirement of improving the reliability of wireless transmission, the base station adopts a spatial diversity transmission scheme.

[0013] The base station adopts a spatial multiplexing transmission scheme in the interference limited area. The channel suitable for the wireless transmission scheme needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmission data streams and is easy to decompose into orthogonal sub-channels.

[0014] The beamforming transmission scheme is adopted in the noise limited area, and the channel suitable for the wireless transmission scheme needs to have the characteristics of channel matrix rank 1 and strong correlation.

[0015] The base station adopts a spatial diversity transmission scheme, and a channel suitable for the wireless transmission scheme needs to have the characteristics of high diversity order and strong correlation.

[0016] The channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and is easily decomposed into orthogonal sub-channels. It is obtained by configuring an intelligent metasurface to achieve selective activation and deactivation of the signal propagation path. The required channel state information is the channel path angle information.

[0017] The channel with a channel matrix rank of 1 and strong correlation characteristics is obtained by configuring an intelligent metasurface to achieve coherent superposition and deactivation of a propagation path in the same direction, and the required channel state information is channel path angle information and path gain phase information.

[0018] The channel with high diversity order and strong correlation characteristics is obtained by configuring the intelligent metasurface multiple times within the channel coherence time to achieve fast channel switching, and the required channel state information is the channel path angle information and the path gain phase information.

[0019] The base station performs channel estimation to obtain the channel state information required by the intelligent super surface configuration method, and then sends the configuration information to the intelligent super surface through wired or wireless transmission.

[0020] When the spatial multiplexing transmission scheme is adopted, the intelligent metasurface is configured on the angular coherence time scale after receiving the configuration information, and the channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and is easy to decompose into orthogonal sub-channels; when the beamforming transmission scheme is adopted, the intelligent metasurface is configured on the channel coherence time scale after receiving the configuration information, and a channel with a channel matrix rank of 1 and strong correlation characteristics is formed; when the spatial diversity transmission scheme is adopted, the intelligent metasurface is configured on the symbol time scale after receiving the configuration information, and a channel with a high diversity order and strong correlation characteristics is formed.

[0021] Beneficial effects: The present invention can overcome the limitation that the performance of traditional wireless transmission schemes depends on channel characteristics, and formulate channels that can improve the transmission performance of the selected transmission mode through multi-time scale intelligent metasurface configuration. For example, a channel with a channel matrix rank greater than or equal to the number of transmitted data streams and easy to decompose into orthogonal sub-channel characteristics is customized for spatial multiplexing transmission to improve its spatial multiplexing gain; a channel with a channel matrix rank of 1 and strong correlation characteristics is customized for beamforming transmission to improve its signal-to-noise ratio; a channel with a high diversity order and strong correlation characteristics is customized for spatial diversity transmission schemes to improve its spatial diversity gain. The present invention transforms the transmission mode that passively relies on the channel into a transmission mode that actively transforms the channel, which can improve the transmission performance and design freedom of the wireless communication system. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a diagram of the wireless communication system architecture adopted by the method of the present invention.

[0023] Figure 2 It is a schematic diagram of channel path propagation of an embodiment of the method of the present invention.

[0024] Figure 3 It is a method flow chart of an embodiment of the method of the present invention.

[0025] Figure 4 It is a schematic diagram of a channel according to an embodiment of the method of the present invention, which has the characteristics that the channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and is easy to decompose into orthogonal sub-channels.

[0026] Figure 5It is a schematic diagram of a channel having a channel matrix rank of 1 and strong correlation characteristics according to an embodiment of the method of the present invention.

[0027] Figure 6 It is a schematic diagram of a channel with high diversity order and strong correlation characteristics according to an embodiment of the method of the present invention. DETAILED DESCRIPTION

[0028] The multi-time scale intelligent metasurface configuration method of the adaptive transmission scheme of the present invention comprises the following steps:

[0029] Step 1: The base station determines the wireless transmission scheme to be adopted according to the wireless transmission performance requirements;

[0030] Step 2: For the adopted wireless transmission scheme, the base station analyzes the channel characteristics suitable for the wireless transmission scheme;

[0031] Step 3: Based on the required channel characteristics, the base station analyzes and determines the intelligent metasurface configuration method and the required channel state information to achieve the channel characteristics;

[0032] Step 4: The base station performs channel estimation to obtain the channel state information required by the intelligent metasurface configuration method;

[0033] Step 5: The base station uses the acquired channel state information to configure the smart metasurface on the corresponding time scale to form a channel suitable for the adopted wireless transmission scheme;

[0034] Step 6: The base station and the user terminal perform data transmission according to the wireless transmission scheme adopted by the channel design formed by the intelligent metasurface configuration.

[0035] In a preferred embodiment, the reconfiguration time of the smart metasurface is less than the symbol time of wireless transmission.

[0036] In a preferred embodiment, the number of smart metasurfaces is greater than or equal to the minimum number of antennas of base stations and user terminals.

[0037] In a preferred embodiment, the multiple time scales can be divided into angle coherence time, channel coherence time and symbol time from large to small. Specifically, the angle coherence time includes several channel coherence times, and the channel coherence time includes several symbol times.

[0038] In a preferred embodiment, according to the performance requirements of improving the wireless transmission rate, the base station adopts a spatial multiplexing transmission scheme in the interference limited area; in order to adapt the spatial multiplexing transmission scheme to give full play to its advantages, the channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmission data streams and is easy to decompose into orthogonal sub-channels; the channel with the characteristics of the channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmission data streams and is easy to decompose into orthogonal sub-channels can be obtained by configuring an intelligent metasurface to realize selective activation and deactivation of the signal propagation path; the channel state information required for configuring the intelligent metasurface to realize selective activation and deactivation of the signal propagation path is the channel path angle information; the base station performs channel estimation to obtain the channel path angle information required to configure the intelligent metasurface; the base station uses the channel path angle information obtained by the channel estimation to configure the intelligent metasurface on the angle coherence time scale to realize a channel suitable for the spatial multiplexing transmission scheme; the base station and the user terminal design a spatial multiplexing transmission scheme according to the channel formed by the intelligent metasurface configuration to transmit data.

[0039] In a preferred embodiment, according to the performance requirements of improving the wireless transmission rate, the base station adopts a beamforming transmission scheme in a noise-limited area; in order to adapt the beamforming transmission scheme to give full play to its advantages, the channel needs to have a channel matrix rank of 1 and strong correlation characteristics; a channel with a channel matrix rank of 1 and strong correlation characteristics can be obtained by configuring an intelligent metasurface to realize the coherent superposition and deactivation of the propagation path; the channel state information required for configuring the intelligent metasurface to realize the coherent superposition and deactivation of the signal propagation path is the channel path angle information and the path gain phase information; the base station performs channel estimation to obtain the channel path angle information and path gain phase information required to configure the intelligent metasurface; the base station uses the channel path angle information and path gain phase information obtained by the channel estimation to configure the intelligent metasurface on the channel coherence time scale to realize a channel suitable for the beamforming transmission scheme; the base station and the user terminal design a beamforming transmission scheme according to the channel formed by the intelligent metasurface configuration to transmit data.

[0040] In a preferred embodiment, according to the performance requirements for improving the reliability of wireless transmission, the base station adopts a spatial diversity transmission scheme; in order to adapt to the spatial diversity transmission scheme to give full play to its advantages, the channel needs to have high diversity order and strong correlation characteristics; the channel with high diversity order and strong correlation characteristics can be obtained by configuring the intelligent super surface multiple times within the channel coherence time to achieve fast channel switching; the channel state information required for configuring the intelligent super surface to achieve fast channel switching is the channel path angle information and the channel gain phase information; the base station performs channel estimation to obtain the channel path angle information and path gain phase information required to configure the intelligent super surface; the base station uses the channel path angle information and path gain phase information obtained by the channel estimation to configure the intelligent super surface multiple times within the symbol time of the channel coherence time scale to achieve a channel suitable for the spatial diversity transmission scheme; the base station and the user terminal design a spatial diversity transmission scheme according to the channel formed by the intelligent super surface configuration, and perform data transmission.

[0041] The present invention is further illustrated below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to explain the present invention and facilitate understanding rather than to limit the scope of the present invention. After reading the present invention, various equivalent modifications made by those skilled in the art to the present invention all fall within the scope defined by the claims attached to this application.

[0042] To facilitate understanding of the content of the present invention, the following introduces the channel model background and other prior art related knowledge involved in the present invention. It should be noted that the method of the present invention is not limited to the expression form of the following specific formula.

[0043] like Figure 1 As shown, with N T A base station with N antennas and R The direct propagation channel between the user terminals of the root antennas is interrupted by obstacles, and the base station and the user terminal transmit data through reflection or transmission of K smart metasurfaces. There is a line-of-sight propagation link between the base station and the smart metasurface, and the number of units of the kth smart metasurface is N. S,k .like Figure 2 As shown in the figure, the channel H between the base station and the user terminal formed by the cascade of K smart metasurfaces can be expressed as

[0044] H=RΞT H

[0045] in, is the array response matrix of the signal reaching the user terminal through all propagation paths, represents the complex space, L R is the number of propagation paths that the signal passes through each smart metasurface to reach the user terminal, a R (·) represents the antenna array response vector of the user terminal, represents the AoA (angle-of-arrival) of the nth path from the mth smart metasurface to the user terminal at the user terminal antenna array; (·) H represents the conjugate transpose operation, is the array response matrix of the signal leaving the base station through all propagation paths, L T is the number of non-line-of-sight propagation paths for signals from the base station to each smart metasurface, a T (·) represents the antenna array response vector of the base station, represents the AoD (angle-of-departure) of the nth path of the mth smart metasurface from the base station in the base station antenna array, m∈{1,2,,K}, Represented by the matrix {Ξ1,...,Ξ K} is a block diagonal matrix, is the equivalent gain matrix of all paths passing through the k-th smart metasurface, and its element in the l-th row and j-th column can be expressed as (Ξ k ) l,j =ξ k,l,j-1 ,in represents the equivalent gain coefficient from the jth incident propagation path to the lth outgoing propagation path on the kth smart metasurface, ρ k represents the large-scale path loss coefficient of the signal from the base station to the user terminal through the kth smart metasurface, α k,R,l represents the small-scale fading coefficient of the lth propagation path of the kth smart metasurface reaching the user terminal, α T,k,j represents the small-scale fading coefficient of the jth path of the kth smart metasurface leaving the base station, a S,k (·) represents the array response vector of the kth smart metasurface, Γ k Represents the response matrix of the kth smart metasurface to electromagnetic waves.

[0046] Based on the above technical background description, Figure 3As shown, an embodiment of the present invention discloses a multi-time scale intelligent metasurface configuration method for an adaptive transmission scheme, which customizes a suitable channel for the adopted transmission scheme by configuring an intelligent metasurface on multiple time scales. The method mainly includes the following steps: first, the base station determines the adopted wireless transmission scheme according to the wireless transmission performance requirements; then, for the adopted wireless transmission scheme, the base station analyzes the channel characteristics suitable for the wireless transmission scheme; secondly, according to the required channel characteristics, the base station analyzes and determines the intelligent metasurface configuration method and the required channel state information for realizing the channel characteristics; thirdly, the base station performs channel estimation to obtain the channel state information required for the intelligent metasurface configuration method; then, the base station configures the intelligent metasurface on the corresponding time scale using the obtained channel state information to form a channel suitable for the adopted wireless transmission scheme; finally, the base station and the user terminal perform data transmission according to the wireless transmission scheme adopted by the channel design formed by the intelligent metasurface configuration. The method specifically includes the following steps:

[0047] Step S1: The base station determines the wireless transmission scheme to be adopted according to the wireless transmission performance requirements. According to the performance requirements of improving the wireless transmission rate, the base station adopts the spatial multiplexing transmission scheme in the interference-limited area and the beamforming transmission scheme in the noise-limited area; according to the performance requirements of improving the wireless transmission reliability, the base station adopts the spatial diversity transmission scheme.

[0048] Step S2: With respect to the adopted wireless transmission scheme, the base station analyzes channel characteristics suitable for the wireless transmission scheme.

[0049] When the base station adopts a spatial multiplexing transmission scheme, such as Figure 4 As shown, the channel suitable for this wireless transmission scheme needs to have the characteristics of high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and can be easily decomposed into orthogonal sub-channels, that is, the channel can be approximately expressed as

[0050]

[0051] In this case, the matrix is ​​subscripted (·) SM represents a subset of the matrix under the spatial multiplexing transmission scheme, satisfy I is the unit matrix, is approximately a diagonal matrix, satisfy

[0052] When the base station adopts a beamforming transmission scheme, such as Figure 5 As shown, the channel suitable for this wireless transmission scheme needs to have the characteristics of channel matrix rank 1 and strong correlation, that is, the channel can be approximately expressed as

[0053]

[0054] In this case, the matrix is ​​subscripted (·) BF represents a subset of the matrix under the beamforming transmission scheme, satisfy 1 K×K is a K-row, K-column matrix of all 1s, is approximately a diagonal matrix, satisfy

[0055] When the base station adopts a spatial diversity transmission scheme, the channel suitable for this wireless transmission scheme must have the characteristics of high diversity order and strong correlation, that is, the channel can be expressed as

[0056]

[0057] Among them, M R is the number of times the smart metasurface is reconfigured within one symbol time, such as Figure 6 As shown, H m is the channel formed by the mth intelligent metasurface configuration, which can be expressed as

[0058]

[0059] In this case, the matrix is ​​subscripted (·) DS,m It represents the subset of the matrix under the spatial diversity transmission scheme when the mth intelligent metasurface is configured. The matrix is ​​added with the subscript (·) DS represents the subset of the matrix under the spatial diversity transmission scheme, satisfy 1 K×K is a K-row, K-column matrix of all 1s, is approximately a diagonal matrix, satisfy

[0060] Step S3: Based on the required channel characteristics, the base station analyzes and determines the intelligent metasurface configuration method and the required channel state information to realize the channel characteristics.

[0061] A channel with high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and can be easily decomposed into orthogonal sub-channel characteristics, can be obtained by configuring the smart metasurface to achieve selective activation and deactivation of the signal propagation path. The phase shift configuration of the nth unit of the kth smart metasurface can be expressed as

[0062]

[0063] in, is the AoD of the lth propagation path from the kth smart metasurface to the user terminal on the smart metasurface array, is the AoA of the propagation path of the kth smart metasurface starting from the base station line of sight on the smart metasurface array. It can be seen that the channel state information required for configuring the smart metasurface to realize the selective activation and deactivation of the signal propagation path is the channel path angle information.

[0064] A channel with a channel matrix rank of 1 and strong correlation characteristics can be obtained by configuring the smart metasurface to achieve coherent superposition and inactivation of the propagation path in the same direction. The phase shift configuration of the nth unit of the kth smart metasurface can be expressed as

[0065]

[0066] in, is the AoD of the lth propagation path from the kth smart metasurface to the user terminal on the smart metasurface array, is the AoA of the kth smart metasurface propagation path from the base station line of sight on the smart metasurface array, ∠α k,R,l ∠α T,k,0 and represent α k,R,l and α T,k,0 It can be seen that the channel state information required for configuring the intelligent metasurface to realize the coherent superposition and deactivation of the signal propagation path is the channel path angle information and the path gain phase information.

[0067] A channel with high diversity order and strong correlation characteristics can be obtained by configuring the smart metasurface multiple times within the channel coherence time to achieve fast channel switching. In the mth configuration within the channel coherence time, the phase shift configuration of the nth unit of the kth smart metasurface can be expressed as

[0068]

[0069] in, and They are respectively the distance from the kth smart metasurface in the mth configuration to the lth user terminal in the channel coherence time. m The AoD of a propagation path on the smart metasurface array and the AoA on the user terminal antenna array, is the AoA of the k-th smart metasurface propagation path from the base station line of sight on the smart metasurface array. In different configurations, the transmission path from the k-th smart metasurface to the user terminal is different, that is, when m≠s, l m ≠l s It can be seen that the channel state information required for configuring the intelligent metasurface to realize the coherent superposition and deactivation of the signal propagation path is the channel path angle information and the path gain phase information.

[0070] Step S4: The base station performs channel estimation to obtain the channel state information required by the intelligent metasurface configuration method. When the base station adopts a spatial multiplexing transmission scheme, the base station needs to perform channel estimation to obtain channel path angle information; when the base station adopts a beamforming or spatial diversity transmission scheme, the base station needs to perform channel estimation to obtain channel path angle information and path gain phase information.

[0071] Step S5: The base station uses the obtained channel state information to configure the intelligent metasurface on the corresponding time scale to form a channel suitable for the adopted wireless transmission scheme. The base station sends the configuration information to the intelligent metasurface by wired or wireless transmission. When the spatial multiplexing transmission scheme is adopted, the intelligent metasurface is configured on the angle coherence time scale after receiving the configuration information to form a channel with high rank, that is, the channel matrix rank is greater than or equal to the number of transmission data streams and is easy to decompose into orthogonal sub-channels; when the beamforming transmission scheme is adopted, the intelligent metasurface is configured on the channel coherence time scale after receiving the configuration information to form a channel with a channel matrix rank of 1 and strong correlation characteristics; when the spatial diversity transmission scheme is adopted, the intelligent metasurface is configured on the symbol time scale after receiving the configuration information to form a channel with high diversity order and strong correlation characteristics.

[0072] Step S6: The base station and the user terminal perform data transmission according to the wireless transmission scheme adopted by the channel design formed by the intelligent metasurface configuration.

[0073] When the base station adopts the spatial diversity transmission scheme, the channel formed by the configuration of the smart metasurface in terms of angular coherence time , the base station and the user terminal design a wireless transmission scheme for data transmission, that is, the base station's precoder F SM and the synthesizer W of the user terminal SM Respectively expressed as

[0074]

[0075] Where E is the total transmit power of the base station;

[0076] When the base station adopts the beamforming transmission scheme, the channel formed by the configuration of the smart metasurface on the channel coherence time The base station and the user terminal design a wireless transmission scheme for data transmission, that is, the base station's precoder f BF and the synthesizer w of the user terminal BF Respectively expressed as

[0077]

[0078] Among them, ||.|| F represents the F-norm;

[0079] When the base station adopts the spatial diversity transmission scheme, the channel formed by the configuration of the smart metasurface within the channel coherence time The base station and the user terminal design a wireless transmission scheme for data transmission, that is, in the mth configuration within the channel coherence time, the base station's precoder F DS and the synthesizer W of the user terminal DS,m Respectively expressed as

[0080]

Claims

1. A multi-time scale intelligent metasurface configuration method for adaptive transmission scheme, characterized in that: The configuration method includes the following steps: Step 1: The base station determines the wireless transmission scheme to be adopted according to the wireless transmission performance requirements; Step 2: For the adopted wireless transmission scheme, the base station analyzes the channel characteristics suitable for the wireless transmission scheme; Step 3: Based on the required channel characteristics, the base station analyzes and determines the intelligent metasurface configuration method and the required channel state information to achieve the channel characteristics; Step 4: The base station performs channel estimation to obtain the channel state information required by the intelligent metasurface configuration method; Step 5: The base station uses the acquired channel state information to configure the smart metasurface on the corresponding time scale to form a channel suitable for the adopted wireless transmission scheme; Step 6: The base station and the user terminal perform data transmission according to the wireless transmission scheme adopted by the channel design formed by the intelligent metasurface configuration; The wireless transmission scheme adopts a spatial multiplexing transmission scheme in interference-limited areas and a beamforming transmission scheme in noise-limited areas according to the performance requirements for improving the wireless transmission rate; Based on the performance requirement of improving wireless transmission reliability, the base station adopts a spatial diversity transmission scheme; The base station adopts a spatial multiplexing transmission scheme in the interference limited area, and the channel suitable for the wireless transmission scheme needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmission data streams and is easy to decompose into orthogonal sub-channels; The beamforming transmission scheme is adopted in the noise limited area, and the channel suitable for the wireless transmission scheme needs to have the characteristics of channel matrix rank 1 and strong correlation; The base station adopts a spatial diversity transmission scheme, and a channel suitable for the wireless transmission scheme needs to have the characteristics of high diversity order and strong correlation.

2. The multi-time scale intelligent metasurface configuration method for adaptive transmission scheme according to claim 1 is characterized in that: The channel needs to have a high rank, that is, the channel matrix rank is greater than or equal to the number of transmitted data streams and is easily decomposed into orthogonal sub-channels. It is obtained by configuring an intelligent metasurface to achieve selective activation and deactivation of the signal propagation path. The required channel state information is the channel path angle information.

3. The multi-time scale intelligent metasurface configuration method for adaptive transmission scheme according to claim 1 is characterized in that: The channel with a channel matrix rank of 1 and strong correlation characteristics is obtained by configuring an intelligent metasurface to achieve coherent superposition and deactivation of a propagation path in the same direction, and the required channel state information is channel path angle information and path gain phase information.

4. The multi-time scale intelligent metasurface configuration method for adaptive transmission scheme according to claim 1, characterized in that: The channel with high diversity order and strong correlation characteristics is obtained by configuring the intelligent metasurface multiple times within the channel coherence time to achieve fast channel switching, and the required channel state information is the channel path angle information and the path gain phase information.

5. The multi-time scale intelligent metasurface configuration method for adaptive transmission scheme according to claim 1, characterized in that: When the spatial multiplexing transmission scheme is adopted, the intelligent metasurface is configured on the angular coherence time scale after receiving the configuration information, forming a channel with a channel matrix rank greater than or equal to the number of transmitted data streams and easy to decompose into orthogonal sub-channels; when the beamforming transmission scheme is adopted, the intelligent metasurface is configured on the channel coherence time scale after receiving the configuration information, forming a channel with a channel matrix rank of 1 and strong correlation characteristics; When adopting the spatial diversity transmission scheme, the intelligent metasurface receives the configuration information and performs configuration on the symbol time scale to form a channel with high diversity order and strong correlation characteristics.

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