CN114040478A - Low-power-consumption intelligent super-surface hardware structure, precoding method and device - Google Patents

Abstract

The present invention provides a low power consumption intelligent metasurface hardware structure, precoding method and device. The hardware structure includes: a plurality of sub-arrays, amplifying circuits corresponding to each sub-array one-to-one, and a phase corresponding to each RIS unit. A shift circuit; wherein each sub-array includes a plurality of RIS units, different RIS units of each sub-array share an amplifying circuit, and each RIS unit uses a different phase shift circuit. The hardware structure effectively solves the problem of high power consumption caused by the introduction of a large number of active amplifying circuits in the active RIS by sharing a sub-array composed of multiple RIS units. Compared with the traditional fully connected structure, the intelligent Metasurface hardware structures can achieve significant energy efficiency improvements. Its precoding method aims at maximizing system energy efficiency, optimizes sub-connection active RIS amplification control and phase shift control, and can effectively save system energy consumed by a large number of amplification circuits.

Description

Low-power smart metasurface hardware structure, precoding method and device

technical field

The present invention relates to the field of wireless communication, and in particular, to a low-power consumption intelligent metasurface hardware structure, precoding method and device.

Background technique

Reconfigurable Intelligent Surface (RIS) is considered to be one of the key technologies for future 6G communication. As shown in part a of Fig. 1, RIS is a large-scale array composed of a large number of passive elements that can tune the phase of the signal, which can intelligently tune the incident signal so that it can be reflected in any specified direction with high gain. Since the cost and power consumption of RIS are very low, it has application value in scenarios such as overcoming interruptions, increasing capacity, and saving transmit power.

As shown in Figure 2, the introduction of RIS brings about the "multiplicative path loss effect", that is, the path loss of the transmitter-RIS-receiver link is the product (rather than the sum) of the path losses of the two channels, which will Makes its gain far less than the direct link gain. This "multiplicative road loss effect" makes it difficult for RIS to show obvious advantages in scenarios with strong direct links, which leads to fatal problems. In order to overcome the "multiplicative path loss effect", a new technology called active RIS was proposed, which can increase the capacity regardless of whether the direct link is strong or weak. Specifically, as shown in part b of Figure 1, unlike the traditional passive RIS that only performs phase regulation on the signal, the active RIS also integrates an amplifier circuit outside the phase shift circuit of each unit, so that the RIS can The reflected signal is amplified to further convert the multiplicative path loss into an additive path loss.

However, the existing active RIS structure is a fully connected structure in which each unit integrates an independent phase shift circuit and an amplifier circuit, which makes the power consumption of the active RIS greatly increase with the increase of the number of units. Taking the static power consumption of each amplifier circuit of 10mW as an example, a 1000-unit active RIS consumes 10W only in the static power consumption of the amplifier circuit, which can already be compared with the transmit power of a typical base station. hard to accept. Therefore, active RIS requires a new structure different from the fully connected structure to save power consumption.

SUMMARY OF THE INVENTION

In view of the problems existing in the prior art, the present invention provides a low-power consumption intelligent metasurface hardware structure, a precoding method and an apparatus.

The present invention provides an intelligent metasurface hardware structure with low power consumption, comprising: a plurality of subarrays, an amplifier circuit corresponding to each subarray one-to-one, and a phase shift circuit corresponding to each intelligent metasurface RIS unit; Each sub-array includes a plurality of RIS units, different RIS units of each sub-array share an amplifying circuit, and each RIS unit uses a different phase shift circuit respectively.

The present invention also provides a precoding method based on the above-mentioned low-power consumption intelligent metasurface hardware structure, including: pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize the precoding of beamforming coding; with the maximum power of the base station and the RIS as constraints, determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; wherein, the system is a user terminal. , RIS and base station system.

According to a precoding method for a low-power consumption smart metasurface hardware structure according to an embodiment of the present invention, the system energy efficiency is determined according to the ratio of the system spectral efficiency and the total system power consumption.

According to a precoding method for a low-power consumption smart metasurface hardware structure according to an embodiment of the present invention, before determining the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, the method further includes: according to The signal-to-noise ratio of the demodulated signals at all user terminals determines the spectral efficiency of the system.

According to the precoding method of the low-power consumption intelligent metasurface hardware structure according to an embodiment of the present invention, before determining the system spectral efficiency according to the signal-to-noise ratio of the demodulated signals at all user terminals, the method further includes: determining each The signal-to-noise ratio of the demodulated signal at a user terminal:

表示基站到用户k的等效信道；Ψ＝diag(ΘΓa)表示有源RIS的波束赋形矩阵；

表示对角相移矩阵，

表示放大系数向量，N为RIS单元总数，L表示放大电路数量；

表示放大电路和相移电路的连接关系；

和

分别表示基站和用户k、基站和有源RIS、以及有源RIS和用户k之间的信道，M为基站天线数；

表示基站波束赋形向量；

σ²分别为有源RIS引入的动态噪声和用户处的加性高斯白噪声的参数。Among them, K is the number of users served by the base station, and j and k represent the corresponding single users;

Represents the equivalent channel from the base station to the user k; Ψ=diag(ΘΓa) represents the beamforming matrix of the active RIS;

represents the diagonal phase shift matrix,

Represents the amplification factor vector, N is the total number of RIS units, and L represents the number of amplification circuits;

Indicates the connection relationship between the amplifier circuit and the phase shift circuit;

and

Respectively represent the channel between the base station and user k, the base station and the active RIS, and the active RIS and user k, and M is the number of base station antennas;

represents the base station beamforming vector;

σ ² are the parameters of the dynamic noise introduced by the active RIS and the additive white Gaussian noise at the user, respectively.

According to a precoding method for a low-power consumption smart metasurface hardware structure according to an embodiment of the present invention, before determining the adjustment results of all phase shift circuits and amplifier circuits that maximize the energy efficiency of the system, the method further includes determining the total system total according to the following formula Power consumption:

表示基站波束赋形向量；Ψ＝diag(ΘΓa)表示有源RIS的波束赋形矩阵；

表示对角相移矩阵，

表示放大系数向量；

表示放大电路和相移电路的连接关系；

表示基站和有源RIS之间的信道；N为RIS单元总数，L表示放大电路数量；

为有源RIS引入的动态噪声的参数。Among them, ξ and ζ represent the reciprocal of the energy conversion coefficient of the base station and the active RIS, W _U and W _BS represent the static power consumption of the user terminal and the base station, W _PS and W _PA represent the static power consumption of the phase shift circuit and the amplifier circuit; K the number of users served by the base station, k represents the corresponding single user,

Represents the base station beamforming vector; Ψ=diag(ΘΓa) represents the beamforming matrix of the active RIS;

represents the diagonal phase shift matrix,

represents the magnification factor vector;

Indicates the connection relationship between the amplifier circuit and the phase shift circuit;

Represents the channel between the base station and the active RIS; N is the total number of RIS units, and L represents the number of amplifier circuits;

Parameter of dynamic noise introduced for active RIS.

According to an embodiment of the present invention, the precoding method for a low power consumption smart metasurface hardware structure is to determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding programs, including:

S1. Use the fractional optimization Dinkelbach algorithm to transform the system energy efficiency optimization problem into a rational programming problem;

S2. Use the Lagrangian dual method to introduce auxiliary variables to transform the rational programming problem into a convex optimization problem;

S3. Keep other variables unchanged, optimize auxiliary variables, base station beamforming, active RIS amplification control and phase shift control variables in sequence;

S4. Repeat S3 until the objective function converges;

S5. Repeat S2-S4 until the objective function converges to 0. At this time, the obtained precoding scheme is an active RIS precoding scheme that maximizes system energy efficiency.

The present invention also provides a low-power consumption intelligent metasurface hardware structure precoding device, comprising: a distribution module for pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize beamforming shape precoding; the processing module is used to determine the adjustment results of the phases of all phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system with the maximum power of the base station and the RIS as the constraint, as the corresponding precoding scheme; Wherein, the system is a system composed of a user terminal, a RIS and a base station.

The present invention also provides an electronic device, comprising a memory, a processor and a computer program stored in the memory and running on the processor, the processor implements the low power consumption as described above when the processor executes the program The steps of the precoding method of the smart metasurface hardware structure.

The present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, realizes the precoding of the hardware structure of the intelligent metasurface with low power consumption as described above. steps of the method.

The low power consumption intelligent metasurface hardware structure, precoding method and device provided by the present invention can effectively solve the problem of active RIS caused by introducing a large number of active amplifying circuits by sharing a sub-array composed of a plurality of RIS units. of high power consumption. Compared with the traditional fully-connected structure, the intelligent metasurface hardware structure of the present invention can obtain significant energy efficiency improvement, and can be used as a high-energy-efficiency implementation of active RIS.

Description of drawings

In order to explain the present invention or the technical solutions in the prior art more clearly, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are the For some embodiments of the invention, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without any creative effort.

1 is a schematic structural diagram of a passive RIS and a fully connected active RIS in the prior art;

2 is a schematic structural diagram of a RIS-assisted MIMO system in the prior art;

3 is a schematic diagram of the hardware structure of a low-power intelligent metasurface provided by the present invention;

4 is a schematic diagram of energy efficiency performance of a low-power smart metasurface hardware structure and a precoding method thereof provided by the present invention;

5 is a schematic structural diagram of an intelligent metasurface hardware structure precoding device with low power consumption provided by the present invention;

FIG. 6 is a schematic structural diagram of an electronic device provided by the present invention.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are part of the embodiments of the present invention. , not all examples. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The low-power consumption smart metasurface hardware structure, precoding method and device of the present invention will be described below with reference to FIGS. 1-6 . FIG. 3 is a schematic diagram of the hardware structure of a low-power smart metasurface provided by the present invention. As shown in FIG. 3 , the present invention provides a low-power smart metasurface hardware structure, including: multiple sub-arrays, one-to-one correspondence with each sub-array The amplifier circuit and the phase shift circuit corresponding to each intelligent metasurface RIS unit; wherein, each sub-array includes multiple RIS units, different RIS units of each sub-array share an amplifier circuit, and each RIS unit uses a different phase shift circuit.

The existing fully-connected active RIS structure is shown in part b of Figure 2. It is based on the original passive RIS in part a of Figure 2. Each unit includes an independent phase shift circuit. amplifying circuit. However, when the number of RIS units is large, the fully connected structure will face a high power consumption problem due to the use of a large number of active amplifier circuits.

In order to solve the problem of high power consumption of the existing fully connected structure of active RIS, in the sub-connection structure shown in FIG. 3 proposed by the present invention, a plurality of RIS units are divided into a sub-array, and each unit in the sub-array is divided into a sub-array. An independent phase shift circuit is used, but an amplifying circuit is shared, that is, each unit independently controls the phase of the signal, but the entire sub-array uses the same signal amplification factor for the amplitude control of the signal.

For the convenience of comparison, consider that each sub-array contains T RIS units, that is, one amplifier circuit serves T RIS units at the same time. At this time, the fully-connected structure becomes a special case of the sub-connected structure when T=1. In the case of the same number of RIS units, the number of amplifying circuits sub-connected to the active RIS becomes 1/T under the fully connected structure, which greatly reduces the energy consumption of the active RIS. At the same time, the degree of freedom of the sub-connected active RIS in the beamforming process is also reduced because the T RIS units share the same amplification factor. However, the present invention shows that the reduction in the beamforming degree of freedom of the sub-connected active RIS structure has little effect, and the system can still obtain a substantial increase in energy efficiency due to the use of the sub-connected structure.

The low-power consumption intelligent metasurface hardware structure provided by the present invention effectively solves the problem of high power consumption caused by the introduction of a large number of active amplifying circuits in the active RIS by sharing one amplifying circuit in a sub-array formed by a plurality of RIS units. Compared with the traditional fully-connected structure, the intelligent metasurface hardware structure of the present invention can obtain significant energy efficiency improvement, and can be used as a high-energy-efficiency implementation of active RIS.

Based on the low-power consumption intelligent metasurface hardware structure proposed by the present invention, the present invention also proposes a corresponding precoding method, including: pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize the beam beam Shaped precoding; with the maximum power of the base station and the RIS as constraints, determine the adjustment results of the phases of all phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; wherein, the The system is composed of user terminal, RIS and base station.

Specifically, aiming at maximizing the energy efficiency of the system, by adjusting the amplification factor of each sub-array amplifier circuit and the phase of each phase shift circuit, the maximum energy efficiency of the system is achieved. Of course, during this process, the power of the base station and the active RIS does not exceed the maximum power.

The low-power consumption intelligent metasurface hardware structure precoding method of the present invention can effectively save the system energy consumed by a large number of amplifying circuits and effectively improve the system energy efficiency.

In the above method embodiment, the system energy efficiency is determined according to a ratio between the system spectral efficiency and the total system power consumption.

Specifically, the system energy efficiency can be expressed as:

Among them, R is the spectral efficiency of the system, and P is the total power consumption of the system. In the precoding scheme, the optimization goal of the present invention is to maximize system energy efficiency.

In the above method embodiment, before determining the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, the method further includes: determining the system according to the signal-to-noise ratio of the demodulated signals at all the user terminals. Spectral efficiency.

Specifically, the system spectral efficiency can be determined as follows:

Among them, K is the number of users served by the base station; SINR _k is the SINR of the demodulated signal at user k.

In the above method embodiment, before determining the system spectral efficiency according to the signal-to-noise ratios of the demodulated signals at all user terminals, the method further includes determining the signal-to-noise ratio of the demodulated signals at each user terminal according to the following formula:

表示基站到用户k的等效信道；Ψ＝diag(ψ)＝diag(ΘΓa)表示有源RIS的波束赋形矩阵；，N为RIS单元总数，L表示放大电路数量；

和

分别表示基站和用户k、基站和有源RIS、以及有源RIS和用户k之间的信道，M为基站天线数；

表示基站波束赋形向量。Among them, K is the number of users served by the base station, and j and k represent the corresponding single users;

Represents the equivalent channel from base station to user k; Ψ=diag(ψ)=diag(ΘΓa) represents the beamforming matrix of active RIS; N is the total number of RIS units, and L represents the number of amplifying circuits;

and

Respectively represent the channel between the base station and user k, the base station and the active RIS, and the active RIS and user k, and M is the number of base station antennas;

represents the base station beamforming vector.

Specifically, an N-unit active RIS-assisted MIMO system is considered, in which one M-antenna base station simultaneously serves K single-antenna users. For the two structures of full connection and sub-connection, L=N/T is used to denote the required number of amplifier circuits, then the beamforming matrix of the active RIS can be expressed as:

Ψ=diag(ψ)=diag(ΘΓa),

表示与传统无源RIS相同的对角相移矩阵，

表示放大系数向量。

定义为一个示性矩阵，它用来表示放大电路和相移电路的连接关系。不失一般性，令

其中

表示克罗内克乘积，

表示全1向量。in,

represents the same diagonal phase shift matrix as conventional passive RIS,

represents the magnification factor vector.

Defined as an illustrative matrix, it is used to represent the connection relationship between the amplifier circuit and the phase shift circuit. Without loss of generality, let

in

represents the Kronecker product,

Represents an all-ones vector.

Then the signal y _k received by user k can be expressed as:

表示相应的基站波束赋形向量，

和

分别表示有源RIS引入的动态噪声和用户k处的加性高斯白噪声。where _sk represents the normalized symbol transmitted to user k,

represents the corresponding base station beamforming vector,

and

denote the dynamic noise introduced by the active RIS and the additive white Gaussian noise at user k, respectively.

In the above method embodiment, before the determining the adjustment results of all the phase shift circuits and amplifier circuits that maximize the energy efficiency of the system, the method further includes determining the total power consumption of the system according to the following formula:

Among them, ξ and ζ represent the reciprocal of the energy conversion coefficient of the base station and the active RIS, W _U and W _BS represent the static power consumption of the user terminal and the base station, and W _PS and W _PA represent the static power consumption of the phase shift circuit and the amplifier circuit.

For the power consumption of the system, it is composed of the transmit power of the base station and the active RIS, and the static power of each component of the system. The total power consumption of the system can be expressed as the above formula.

以及Θ＝diag(θ)，则系统能效最大化问题可以表示为：Combining the above signal models, we can write

and Θ=diag(θ), the system energy efficiency maximization problem can be expressed as:

stC ₁ :

C ₂ :

_C3 :

C ₄ :

Among them, constraints _C1 and _C2 limit the maximum power _of the base station and active RIS, respectively, and constraints C3 and _C4 limit the feasible sets of phase-shift control Θ and amplification control a, respectively.

By solving the above optimization problem, the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplifier circuits can be obtained, that is, the corresponding precoding scheme.

In a method embodiment, the determining the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme, includes: S1. Using the fractional type to optimize Dinkelbach The algorithm transforms the system energy efficiency optimization problem into a rational programming problem; S2. Uses the Lagrangian dual method to introduce auxiliary variables, and converts the rational programming problem into a convex optimization problem; S3. Keep other variables unchanged, optimize the auxiliary in sequence Variables, base station beamforming, active RIS amplification control and phase shift control variables; S4. Repeat S3 until the objective function converges; S5. Repeat S2-S4 until the objective function converges to 0, the precoding scheme obtained at this time is Active RIS precoding scheme to maximize system energy efficiency. The specific instructions are as follows:

In order to facilitate the processing of the above-mentioned fractional objective function, the embodiment of the present invention first uses the Dinkelbach algorithm in the fractional programming to convert it into a rational form. Specifically, the optimal energy efficiency η ^opt satisfies:

It shows that the optimal energy efficiency η ^opt can be obtained by iteratively solving the following problem:

stC ₁ , C ₂ , C ₃ , C ₄ .

和

将问题等价改写为：Since this problem is still non-convex, the present invention introduces auxiliary variables

and

Equivalently rewrite the problem as:

stC ₁ , C ₂ , C ₃ , C ₄ .

in:

At this point, the optimal solutions for all variables in the problem can be obtained by iterative optimization. In the precoding scheme proposed by the present invention, the optimization of each variable is the optimal solution obtained when other variables are fixed, and the specific closed-form expression is as follows.

和

为0得到最优解：(1) Optimal auxiliary variable: For all k∈{1,…,K}, let

and

0 to get the optimal solution:

in

(2) Optimal base station beamforming: Definition:

are the transmit power of the base station and the active RIS, respectively. For optimal base station beamforming, the problem can be written as:

stC ₁ :

C ₂ :

in:

This is a standard QCQP (quadratic constraint quadratic programming) problem, so it can be solved by existing methods such as ADMM (alternating direction method of multipliers).

以及β_j＝Gw_j，则

可以被改写为：(3) Optimal Active RIS Beamforming: Definition

and β _j =Gw _j , then

can be rewritten as:

From this, the active RIS beamforming problem can be written as:

stC ₂ :

C ₃ , C ₄ ,

in:

Again, this is a standard QCQP problem and thus can be solved by existing methods.

Finally, considering the constraints C ₃ and C ₄ , the optimal phase shift control Θ ^opt and the optimal amplification factor a ^opt are respectively:

Θ ^opt =diag(exp(jarg(ψ ^opt ))),

a ^opt =Γ ^-1 diag(exp(-jarg(ψ ^opt )))ψ ^opt ,

where Γ ^-1 represents the pseudo-inverse of the matrix Γ.

Through the above precoding method, the sub-connected active RIS structure provided by the present invention can effectively solve the problem of high power consumption caused by the introduction of a large number of active amplifying circuits in the active RIS. Compared with the traditional fully-connected structure, the sub-connected structure can obtain The 22% energy efficiency improvement, as shown in FIG. 4 , verifies that the sub-connection structure provided by the present invention can be used as a high-energy-efficiency implementation of the active RIS.

The precoding device of the low-power consumption intelligent metasurface hardware structure provided by the present invention is described below, the precoding device of the low-power consumption intelligent metasurface hardware structure described below and the low-power consumption intelligent metasurface hardware described above are described below. The precoding methods of the structures can refer to each other correspondingly.

FIG. 5 is a schematic structural diagram of a low-power consumption intelligent metasurface hardware structure precoding device provided by the present invention. As shown in FIG. 5 , the low power consumption intelligent metasurface hardware structure precoding device includes: an allocation module 501 and a processing Module 502. Wherein, the allocation module 501 is used to pre-adjust the phase of each phase shift circuit and the amplification factor of each amplifier circuit to realize precoding of beamforming; the processing module 502 is used to take the maximum power of the base station and the RIS as the constraint condition , determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; wherein, the system is a system composed of a user terminal, a RIS and a base station.

The apparatus embodiments provided in the embodiments of the present invention are for implementing the foregoing method embodiments. For specific processes and details, please refer to the foregoing method embodiments, which will not be repeated here.

FIG. 6 is a schematic structural diagram of an electronic device provided by the present invention. As shown in FIG. 6 , the electronic device may include: a processor (processor) 601, a communication interface (Communications Interface) 602, a memory (memory) 603 and a communication bus 604, The processor 601 , the communication interface 602 , and the memory 603 communicate with each other through the communication bus 604 . The processor 601 can invoke the logic instructions in the memory 603 to execute a low-power smart metasurface hardware structure. The method includes: pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize the beam Shaped precoding; with the maximum power of the base station and the RIS as constraints, determine the adjustment results of the phases of all phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; wherein, the The system is composed of user terminal, RIS and base station.

In addition, the above-mentioned logic instructions in the memory 603 may be implemented in the form of software functional units and may be stored in a computer-readable storage medium when sold or used as an independent product. Based on this understanding, the technical solution of the present invention can be embodied in the form of a software product in essence, or the part that contributes to the prior art or the part of the technical solution. The computer software product is stored in a storage medium, including Several instructions are used to cause a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes: U disk, mobile hard disk, Read-Only Memory (ROM, Read-Only Memory), Random Access Memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes .

In another aspect, the present invention also provides a computer program product, the computer program product comprising a computer program stored on a non-transitory computer-readable storage medium, the computer program comprising program instructions, when the program instructions are executed by a computer During execution, the computer can execute the intelligent metasurface hardware structure with low power consumption provided by the above methods, and the method includes: based on pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize beamforming with the maximum power of the base station and RIS as constraints, determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; wherein, the system is A system composed of user terminal, RIS and base station.

In another aspect, the present invention also provides a non-transitory computer-readable storage medium on which a computer program is stored, the computer program being implemented by a processor to execute the low-power consumption smart metasurface provided by the above embodiments Hardware structure, the method includes: pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit to realize precoding of beam forming; The maximum adjustment results of the phases of all the phase shift circuits and the coefficients of the amplification circuits are used as the corresponding precoding scheme; wherein, the system is a system composed of a user terminal, an RIS and a base station.

The device embodiments described above are only illustrative, wherein the units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in One place, or it can be distributed over multiple network elements. Some or all of the modules may be selected according to actual needs to achieve the purpose of the solution in this embodiment. Those of ordinary skill in the art can understand and implement it without creative effort.

From the description of the above embodiments, those skilled in the art can clearly understand that each embodiment can be implemented by means of software plus a necessary general hardware platform, and certainly can also be implemented by hardware. Based on this understanding, the above-mentioned technical solutions can be embodied in the form of software products in essence or the parts that make contributions to the prior art, and the computer software products can be stored in computer-readable storage media, such as ROM/RAM, magnetic A disc, an optical disc, etc., includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to perform the methods described in various embodiments or some parts of the embodiments.

Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, but not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that it can still be Modifications are made to the technical solutions described in the foregoing embodiments, or some technical features thereof are equivalently replaced; and these modifications or replacements do not make the essence of the corresponding technical solutions depart from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims (10)

1. a kind of intelligent metasurface hardware structure of low power consumption, is characterized in that, comprises: a plurality of sub-arrays, amplifying circuits corresponding to each sub-array one-to-one, and a phase-shift circuit corresponding to each intelligent metasurface RIS unit; Wherein, each sub-array includes a plurality of RIS units, different RIS units of each sub-array share an amplifying circuit, and each RIS unit uses a different phase shift circuit respectively. 2. a kind of precoding method based on the low power consumption intelligent metasurface hardware structure according to claim 1, is characterized in that, comprises: Precoding for beamforming based on pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifying circuit; Taking the maximum power of the base station and the RIS as a constraint, determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplifier circuits that maximize the energy efficiency of the system, as the corresponding precoding scheme; Wherein, the system is a system composed of a user terminal, a RIS and a base station. 3 . The low-power consumption intelligent metasurface hardware structure precoding method according to claim 2 , wherein the system energy efficiency is determined according to the ratio of the system spectral efficiency and the total system power consumption. 4 . 4. The precoding method of the intelligent metasurface hardware structure of low power consumption according to claim 3, characterized in that, the adjustment result of the phase of all phase shift circuits and the coefficient of the amplification circuit that maximizes the energy efficiency of the system is determined. Before, also included: The system spectral efficiency is determined according to the signal-to-noise ratio of the demodulated signals at all user terminals. 5. The precoding method of the intelligent metasurface hardware structure with low power consumption according to claim 4, characterized in that, before determining the system spectral efficiency according to the signal-to-noise ratio of the demodulated signals at all user terminals, the method further comprises: , and the signal-to-noise ratio of the demodulated signal at each user terminal is determined according to the following formula:

Among them, K is the number of users served by the base station, and j and k represent the corresponding single users;

Represents the equivalent channel from base station to user k; Ψ=diag(ΘFa) represents the beamforming matrix of active RIS;

represents the diagonal phase shift matrix,

Represents the amplification factor vector, N is the total number of RIS units, and L represents the number of amplification circuits;

Indicates the connection relationship between the amplifier circuit and the phase shift circuit;

and

respectively represent the channel between the base station and user k, the base station and the active RIS, and the active RIS and user k, M is the number of base station antennas; w _j ,

represents the base station beamforming vector;

σ ² are the parameters of the dynamic noise introduced by the active RIS and the additive white Gaussian noise at the user, respectively. 6. The precoding method of the intelligent metasurface hardware structure with low power consumption according to claim 3, characterized in that, before said determining the adjustment results of all phase shift circuits and amplifying circuits that maximize the energy efficiency of the system, the method further comprises: Determine the total system power consumption according to the following formula:

Among them, ξ and ζ represent the reciprocal of the energy conversion coefficient of the base station and the active RIS, W _U and W _BS represent the static power consumption of the user terminal and the base station, W _PS and W _PA represent the static power consumption of the phase shift circuit and the amplifier circuit; K the number of users served by the base station, k represents the corresponding single user,

Represents the base station beamforming vector; Ψ=diag(ΘFa) represents the beamforming matrix of the active RIS;

represents the diagonal phase shift matrix,

represents the magnification factor vector;

Indicates the connection relationship between the amplifier circuit and the phase shift circuit;

Represents the channel between the base station and the active RIS; N is the total number of RIS units, and L represents the number of amplifier circuits;

Parameter of dynamic noise introduced for active RIS. 7. The precoding method of the intelligent metasurface hardware structure with low power consumption according to claim 3, wherein the adjustment result of the phase of all phase shift circuits and the coefficient of the amplification circuit that maximizes the energy efficiency of the system is determined. , as the corresponding precoding scheme, including: S1. Use the fractional optimization Dinkelbach algorithm to transform the system energy efficiency optimization problem into a rational programming problem; S2. Use the Lagrangian dual method to introduce auxiliary variables to transform the rational programming problem into a convex optimization problem; S3. Keep other variables unchanged, optimize auxiliary variables, base station beamforming, active RIS amplification control and phase shift control variables in sequence; S4. Repeat S3 until the objective function converges; S5. Repeat S2-S4 until the objective function converges to 0. At this time, the obtained precoding scheme is an active RIS precoding scheme that maximizes system energy efficiency. 8. A precoding device based on the low-power consumption intelligent metasurface hardware structure according to claim 1, characterized in that, comprising: a distribution module, configured to implement precoding for beamforming based on pre-adjusting the phase of each phase shift circuit and the amplification factor of each amplifier circuit; The processing module is used to determine the adjustment results of the phases of all the phase shift circuits and the coefficients of the amplifier circuits that maximize the energy efficiency of the system, taking the maximum power of the base station and the RIS as a constraint, as a corresponding precoding scheme; Wherein, the system is a system composed of a user terminal, a RIS and a base station. 9. An electronic device comprising a memory, a processor and a computer program stored on the memory and running on the processor, wherein the processor implements the program as claimed in claim 2 when the processor executes the program Steps of the precoding method for the low-power consumption intelligent metasurface hardware structure described in any one of to 7. 10. A non-transitory computer-readable storage medium on which a computer program is stored, characterized in that, when the computer program is executed by a processor, the intelligent low-power consumption according to any one of claims 2 to 7 is realized. Steps of a precoding method for a metasurface hardware structure.

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