Electronic control movable antenna array design and multi-user communication method, and electronic control movable antenna array

Abstract

The invention discloses a design of an electrically controlled movable antenna array, a multi-user communication method and an electrically controlled movable antenna array, and the method comprises the steps: constructing an electrically controlled movable antenna through controlling the state of a radio frequency assembly between pixel antennas in a reconfigurable pixel antenna; a plurality of electrically-controlled movable antennas are combined and connected with radio frequency links one by one, and a partially-connected electrically-controlled movable antenna array is constructed; an electrically-controlled movable antenna is expanded and is connected with a radio frequency link through a switching network, so that a full-connection electrically-controlled movable antenna array is constructed; under the condition that the transmitting power constraint and the hardware constraint are met, antenna selection of partially-connected and fully-connected electric control movable antenna arrays and corresponding baseband multi-user beam forming are designed, and the multi-user communication and rate are maximized. According to the invention, the position of the antenna array can be rapidly adjusted through electric control, a rapidly changing channel environment can be effectively dealt with, and the performance of multi-user communication is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of wireless communications, and in particular to a design of an electrically controlled movable antenna array, a multi-user communication method, and an electrically controlled movable antenna array. Background Art

[0002] With the emergence of applications such as the Internet of Things, smart homes, and industrial automation, wireless communications are facing increasingly higher performance requirements, including higher data rates, wider coverage, lower power consumption, and greater adaptability. Therefore, enhancing the capabilities, efficiency, and flexibility of wireless communication systems has become a major focus of current research. Traditional MIMO communications enhance transmission performance by utilizing the inherent degrees of freedom of the channel (Reference [1]: R.Heath and A.Paulraj, “Switching between diversity and multiplexing in MIMO systems,” IEEE Trans. Wireless Commun., vol. 53, no. 6, pp. 962–968, June 2005.). However, they usually use fixed-position antennas, which limits their design flexibility. Antenna positions can significantly affect communication performance because they affect the strength of the received signal power. In the case of fixed-position antennas, the received power of the antenna remains fixed under given channel conditions and cannot be enhanced through optimization, thereby limiting their communication performance. To address this problem, antenna selection can adapt to instantaneous channel state information by deploying a large number of candidate antennas and selecting a portion of them for wireless communication, thereby overcoming the limitations of fixed-position antennas. However, this approach will bring about a lot of hardware costs, and the physical size constraints of the antennas impose a minimum spacing between candidate antennas, limiting the use of channels at specific discrete locations for wireless communication. To address these challenges, recent research has explored new methods to achieve flexible mobility of radiating elements, including the use of movable antennas, fluid antennas, and flexible smart metasurfaces, where movable antennas use mechanical devices such as motors to reposition antenna elements within the transmission area, fluid antennas rely on liquid pumping or pressure regulation to adjust the antenna position, and flexible smart metasurfaces use micromechanical mechanisms to reconfigure the position of radiating elements. The advantage of these key technologies is that they can move freely within a defined spatial area, providing greater design flexibility. In the literature [2], the authors proposed a multi-user beamforming method based on a mechanically movable antenna array, which achieves multi-user communication and rate maximization by jointly optimizing the position of the antenna in the transmission area and baseband beamforming. (Literature [2]: B. Feng, Y. Wu, X.-G.However, the implementation of the above technologies all relies on mechanical adjustment, which results in a slow position update process, making them unsuitable for rapidly changing channel environments. Summary of the Invention

[0003] The purpose of the present invention is to provide an electrically controlled movable antenna array design and a multi-user communication method, and an electrically controlled movable antenna array. It proposes to control the state of the radio frequency components between pixel antennas in a reconfigurable pixel antenna, change the equivalent electric center of antenna radiation to equivalently change the position of the antenna array, thereby constructing an electrically controlled movable antenna, realizing electrically controlled rapid adjustment of the position of the antenna array, and being able to effectively cope with rapidly changing channel environments.

[0004] In order to achieve the above technical objectives, the technical solution adopted by the present invention is:

[0005] In a first aspect, the present invention discloses a design of an electrically controlled movable antenna array and a multi-user communication method, the method comprising the following steps:

[0006] An electrically controlled movable antenna is constructed based on a reconfigurable pixel antenna. The electrically controlled movable antenna constructs a set of predefined and positionally discrete selectable candidate antennas by controlling the states of the RF components interconnected between the pixel antennas.

[0007] Arrange multiple electrically controllable movable antennas and directly connect them one-to-one with multiple radio frequency links to construct a partially connected electrically controllable movable antenna array, where each radio frequency link selects one antenna from the set of connected candidate antennas for transmission;

[0008] An electrically controlled movable antenna is expanded and connected to a radio frequency link through a switch network to construct a fully connected electrically controlled movable antenna array. Each radio frequency link in the fully connected electrically controlled movable antenna array has the ability to connect to all candidate antennas. By dynamically controlling the state of the radio frequency components between pixel antennas, one or more candidate antennas are selected and connected to the radio frequency link.

[0009] A partially connected electrically controlled movable antenna array or a fully connected electrically controlled movable antenna array is used as a base station to communicate with K single-antenna users. Under the constraints of transmit power and antenna selection, antenna selection and multi-user beamforming are designed to maximize multi-user communication and rate. The antenna selection and multi-user beamforming problems are:

[0010]

[0011] t∈Φ P orΦ F

[0012] Among them, R k represents the communication sum rate of the kth user; represents the multi-user transmit beamforming matrix; It represents the vector representation of antenna selection T; P represents the maximum allowed transmit power; Φ P represents the feasible set of antenna selections under the partially connected architecture, Φ F represents the feasible set of antenna selection under the fully connected architecture.

[0013] Furthermore, the reconfigurable pixel antenna is composed of multiple pixel antennas, which are connected by RF components. By controlling the state of the RF components between the pixel antennas, the antenna radiation pattern is changed to adjust the equivalent electric center of the antenna array and physically change the position of the antenna array.

[0014] Furthermore, under the constraints of transmit power and antenna selection, with the goal of maximizing multi-user communication and rate, the process of designing antenna selection and multi-user beamforming includes the following steps:

[0015] Setting corresponding multi-user communication system parameters based on a partially connected electrically controlled movable antenna array architecture and a fully connected electrically controlled movable antenna array architecture;

[0016] Based on the Saleh-Valenzuela model, the channel transmission models for the partially connected electrically controlled movable antenna array architecture and the fully connected electrically controlled movable antenna array architecture are designed respectively.

[0017] While satisfying the transmission power constraints and antenna selection constraints, the goal is to maximize multi-user communication and rate. The antenna selection and multi-user beamforming problems are established and solved, and the antenna selection and multi-user beamforming are designed.

[0018] Furthermore, the channel transmission model of the partially connected electrically controlled movable antenna array and the fully connected electrically controlled movable antenna array is:

[0019]

[0020] Among them, h k represents the channel vector between the base station and the kth user, N t Indicates the total number of antennas in the antenna array, L k Indicates the number of paths, and denote the channel gain, azimuth angle and elevation angle of the lth path respectively; represents the array steering vector;

[0021]

[0022] in The coordinates of the candidate antenna located at the mth row and nth column are expressed as [xn ,0,z m ];

[0023] For a partially connected electrically controlled movable antenna array, assuming that the candidate antenna is located at the sth row and tth column of the electrically controlled movable antenna at the pth row and qth column, x n and z m Expressed as:

[0024] x n =(M c -q)d e +(S c -t)d c , z m =(M r -p)d e +(S r -s)d c

[0025] where d c represents the interval between adjacent candidate antennas, d e Represents the spacing between adjacent electrically controlled movable antennas, M r and M c denote the number of rows and columns of the partially connected electrically controlled movable antenna array, S r and S c Respectively represent the number of candidate antenna rows and columns supported by each electrically controlled movable antenna;

[0026] For a fully connected electrically controlled movable antenna array, x n and z m Expressed as:

[0027] x n =(N c -n)d c , z m =(N r -m)d c

[0028] where N c and N r They represent the number of candidate antenna rows and columns of the fully connected electrically controlled movable antenna array.

[0029] Furthermore, the antenna selection feasible set Φ under the partially connected electrically controlled movable antenna array architecture is P It is composed of a vector t that satisfies the following requirements: ①[t] p ∈{0,1},p=1,2,...,N t ,② ③ ④

[0030] Feasible set Φ for antenna selection under fully connected electrically controlled movable antenna array architecture F It is composed of a vector t that satisfies the following requirements: ① [t] p ∈{0,1},p=1,2,...,N t ,② ③ in, Represents the spacing constraint matrix, denoted as [S] :,s =vec{B m,n}, s=(n-1)N r +m,m=1,…,N r 、n=1,…,N c , represents the selection constraint by marking the positions within the exclusion zone with 1, while the positions outside the zone remain zero, i.e.:

[0031]

[0032] represents the antenna selection constraint matrix under the partially connected architecture, expressed as [Q] :,s =vec{C p,q}, s=(q-1)M r +p,p=1,…,M r ,q=1,…,M c , The antenna selection constraints in the partially connected architecture are characterized by marking the candidate antenna positions located at the p-th row and q-th column with 1, while all other positions remain zero, i.e.:

[0033]

[0034] Furthermore, the process of solving the antenna selection and multi-user beamforming problem includes the following steps:.

[0035] In step S41, the power constraint is removed from the antenna selection and multi-user beamforming problem by utilizing the property that any non-trivial stationary point of the beamforming matrix F that maximizes multi-user communication and rate will satisfy the equal power constraint. The new optimization problem is:

[0036]

[0037] stt∈Φ P orΦ F

[0038] in, Expressed as:

[0039]

[0040] in diag{·} represents the diagonalization of a vector;

[0041] Step S42: The objective function Converted to equivalent form:

[0042]

[0043] stt∈Φ P orΦ F

[0044] Among them, e k Defined as:

[0045]

[0046] Among them, u k is the receiving factor of the kth user;

[0047] Step S43: For the feasible set Φ P and Φ F The antenna selection constraints in the .txt file are processed as follows:

[0048] Step S431, using the equivalent continuous equation to process Φ P and Φ F Binary constraints in [T] m,n ∈{0,1}, expressed as:

[0049] [t] p (1-[t] p )=0,forp=1,2,…,N t

[0050] Step S432: Use a penalty-based method to relax the equality constraint and incorporate it into the objective, rewriting the optimization problem as follows:

[0051]

[0052] [t] p ∈[0,1],forp=1,2,…,N t

[0053] in, represents the weighted sum of the original objective function and the penalty term of the relaxed constraint;

[0054] Step S44: Solve the above optimization problem to obtain antenna selection and multi-user beamforming.

[0055] In a second aspect, the present invention discloses an electrically controlled movable antenna array, wherein the electrically controlled movable antenna array includes a partially connected electrically controlled movable antenna array and a fully connected electrically controlled movable antenna array;

[0056] The partially connected electrically controlled movable antenna array is constructed by arranging multiple electrically controlled movable antennas and directly connecting them one-to-one with multiple radio frequency links. Each radio frequency link selects one antenna from a set of connected candidate antennas for transmission. The fully connected electrically controlled movable antenna array is constructed by extending one electrically controlled movable antenna and connecting it to radio frequency links through a switch network. Each radio frequency link has the ability to connect to all candidate antennas. One or more candidate antennas are selected and connected to the radio frequency links by dynamically controlling the state of radio frequency components between pixel antennas.

[0057] Each electrically controlled movable antenna is composed of multiple pixel antennas, which are connected by radio frequency components. By controlling the state of the radio frequency components between the pixel antennas, the antenna radiation pattern is changed to adjust the equivalent electrical center of the antenna array and physically change the position of the antenna array.

[0058] The electrically controlled movable antenna array selects a partially connected electrically controlled movable antenna array or a fully connected electrically controlled movable antenna array as a base station for communication with K single-antenna users. Under the conditions of satisfying transmit power constraints and antenna selection constraints, with the goal of maximizing multi-user communication and rate, antenna selection and multi-user beamforming are designed using the method described in any one of claims 1 to 6.

[0059] Compared with the prior art, the present invention has the following beneficial effects:

[0060] First, the electrically controlled movable antenna array design and multi-user communication method and the electrically controlled movable antenna array of the present invention control the state of the radio frequency components between the pixel antennas in the reconfigurable pixel antenna, change the equivalent electric center of the antenna radiation to change the position of the antenna array, thereby constructing an electrically controlled movable antenna, realizing electrically controlled rapid adjustment of the position of the antenna array, and being able to effectively cope with rapidly changing channel environments.

[0061] Secondly, the electrically controlled movable antenna array design and multi-user communication method of the present invention, as well as the electrically controlled movable antenna array, for a movable antenna array constructed with reconfigurable pixel antennas, utilizes the movable characteristics of the antennas, which has higher design flexibility than the existing fixed antenna architecture.

[0062] Third, the electrically controlled movable antenna array design and multi-user communication method and the electrically controlled movable antenna array of the present invention, for the multi-user communication method, fully exploit the characteristics of the electrically controlled movable antenna array and utilize optimization methods to achieve multi-user communication performance that is better than existing methods; specifically, the design goal of the multi-user communication problem is to maximize multi-user communication and rate while satisfying the transmission power constraints and antenna selection constraints, and design antenna selection and multi-user beamforming, thereby fully utilizing the characteristics of the electrically controlled movable antenna array and can effectively cope with rapidly changing channel environments. BRIEF DESCRIPTION OF THE DRAWINGS

[0063] Figure 1 This is a schematic diagram of the electrically controlled movable antenna array architecture designed in an embodiment of the present invention;

[0064] Figure 2 2. This is a schematic diagram of multi-user communication with different architectures and rate changes with antenna position intervals under a uniform linear array simulated in an embodiment of the present invention;

[0065] Figure 3 Schematic diagram of multi-user communication with different architectures and rate changes with antenna position intervals under a uniform planar array simulated in an embodiment of the present invention;

[0066] Figure 4 1 is a schematic diagram of multi-user communication with different architectures and rate changes with signal-to-noise ratio under a uniform planar array simulated in an embodiment of the present invention;

[0067] Figure 5 Schematic diagram of multi-user communication with different architectures and rate changes with the number of paths under a uniform planar array simulated in an embodiment of the present invention;

[0068] Figure 6 This is a schematic diagram of multi-user communication with different architectures and the change of the rate with the number of users under a uniform planar array simulated in an embodiment of the present invention. DETAILED DESCRIPTION

[0069] The embodiments of the present invention are described in further detail below with reference to the accompanying drawings.

[0070] The present invention discloses an electrically controlled movable antenna array design and a multi-user communication method, the method comprising the following steps:

[0071] S1: Build an electrically controllable movable antenna based on a reconfigurable pixel antenna. This electrically controllable movable antenna constructs a set of predefined and discretely selectable candidate antennas by controlling the state of the RF components interconnected between the pixel antennas. Specifically, a specific candidate antenna is selected for transmission by electronically controlling the state of the RF components between the pixel antennas, thereby enabling electronically controlled rapid adjustment of the antenna position.

[0072] S2, arranging multiple electrically controllable movable antennas and directly connecting them to radio frequency links to construct a partially connected electrically controllable movable antenna array, wherein each electrically controllable movable antenna in the partially connected electrically controllable movable antenna array is individually connected to a single radio frequency link, and each radio frequency link can only select one antenna from the set of connected candidate antennas for transmission;

[0073] S3: Expand an electrically controlled movable antenna and connect it to the RF link through a switch network to build a fully connected electrically controlled movable antenna array. Each RF link in the fully connected electrically controlled movable antenna array has the ability to connect to all candidate antennas. By dynamically controlling the state of the RF components between pixel antennas, multiple candidate antennas can be selected at once and then connected to the RF link.

[0074] S4, under the constraints of transmit power and antenna selection, designs antenna selection and multi-user beamforming with the goal of maximizing multi-user communication and rate.

[0075] (1) Design of an electrically controlled movable antenna array with a partially connected architecture

[0076] like Figure 1 As shown, the description of the electrically controlled movable antenna array under the partial connection architecture designed by the present invention is as follows:

[0077] Set up a base station to communicate with K single-antenna users, where the antenna position at the user is fixed and the base station adopts a partially connected electrically controlled movable antenna array architecture. The transmitting array includes M r Line and M c A series of electrically controlled movable antennas, each of which can support candidate antenna S r Row and s c Columns, therefore, each row in the partially connected architecture includes N c =M c S c candidate antennas, each column includes N r =M r S r candidate antennas, and the total number of candidate antennas in the electrically controlled movable antenna array is N t =N r N c , and the interval between adjacent candidate antennas is represented by d c , the interval between adjacent electrically controlled movable antennas is represented by d e .

[0078] (2) Design of an electrically controlled movable antenna array under a fully connected architecture

[0079] The description of the electrically controlled movable antenna array under the fully connected architecture designed by the present invention is as follows:

[0080] Set up a base station to communicate with K single-antenna users, where the antenna position at the user is fixed, and the base station adopts a fully connected electrically controlled movable antenna array architecture. Similar to the partially connected electrically controlled movable antenna array, each row in the fully connected electrically controlled movable antenna array includes N c candidate antennas, each column includes N r candidate antennas, the total number of candidate antennas is N t =N r N c , and the interval between adjacent candidate antennas is represented by d c .

[0081] The reconfigurable pixel antenna consists of multiple pixel antennas connected by RF components. By controlling the state of the RF components between the pixel antennas, the antenna radiation pattern is altered to adjust the equivalent electrical center of the antenna element, effectively physically changing the position of the antenna element, thus creating an electrically controllable movable antenna. By controlling the state of the interconnected RF components between the pixel antennas, the electrically controllable movable antenna constructs a set of predefined and discretely selectable candidate antennas. By electronically controlling the state of the RF components between the pixel antennas, a specific candidate antenna is selected for transmission, enabling electronically controlled rapid adjustment of the antenna position.

[0082] (3) Designing a channel transmission model under a partially connected architecture

[0083] The channel transmission model under the partial connection architecture of the present invention is:

[0084] Assume that there are L total distances from the base station to the kth user k transmission paths, each of which is represented by azimuth, elevation, and channel gain. According to the widely used Saleh-Valenzuela (SV) model, the channel under the partially connected architecture is generally modeled as:

[0085]

[0086] Among them, h k represents the channel vector between the base station and the kth user, N t Indicates the total number of antennas in the antenna array, L k 、 and denote the number of paths, the channel gain of the lth path, the azimuth angle, and the elevation angle respectively; the coordinates of the candidate antenna located in the mth row and the nth column are expressed as [x n ,0,z m ],in Then the array steering vector Expressed as:

[0087]

[0088] Where λ represents the carrier wavelength, Denotes the tensor product. For a partially connected electrically controlled movable antenna array architecture, assume that the candidate antenna at the sth row and tth column of the electrically controlled movable antenna located at the pth row and qth column corresponds to the antenna at the mth row and nth column of the antenna array, i.e., m = (p-1)S r +s,n=(q-1)S c +t, then x n and z m It can be expressed as:

[0089] x n =(M c -q)d e +(S c -t)d c , z m =(M r -p)d e +(S r -s)d c

[0090] (4) Designing a channel transmission model under a fully connected architecture

[0091] The channel transmission model under the fully connected architecture of the present invention is:

[0092] Assume that there are L total distances from the base station to the kth user k transmission paths, each of which is represented by azimuth, elevation and channel gain. According to the SV model, the channel under the fully connected architecture is generally modeled as

[0093]

[0094] Among them, h k represents the channel between the base station and the kth user, N t Indicates the total number of antennas in the antenna array, L k 、 and denote the number of paths, the channel gain of the lth path, the azimuth angle, and the elevation angle respectively; the coordinates of the candidate antenna located in the mth row and the nth column are expressed as [x n ,0,z m ],in Then the array steering vector Expressed as:

[0095]

[0096] For the fully connected electrically controlled movable antenna array architecture, x n and z m It can be expressed as:

[0097] x n =(N c -n)d c , z m =(N r -m)d c

[0098] (5) Design antenna selection and multi-user beamforming

[0099] The antenna selection and multi-user beamforming problem proposed in this invention can be described as follows:

[0100] (5.1) The communication sum rate of the kth communication user is expressed as:

[0101]

[0102] in, The vector representation of the antenna selection matrix T, f k represents the k-th column of F, represents the multi-user transmit beamforming matrix, σ 2 represents the noise power, and diag{·} represents the diagonalization of the vector.

[0103] (5.2) According to the transmission power constraint, the maximum transmission power is determined to be P, so that the user transmission power is less than the maximum transmission power, that is,

[0104] (5.3) Antenna selection matrix is a binary selection matrix, requiring [T] m,n ∈{0,1}, that is, [t] p ∈{0,1},p=1,2,...,N t .

[0105] (5.4) The base stations select N s antennas for transmission, requiring Right now

[0106] (5.5) In order to avoid the coupling effect between the selected antennas, the minimum spacing between the selected antennas is usually more than λ / 2, requiring Right now in, Represents the spacing constraint matrix, denoted as [S] :,s =vec{B m,n}, s=(n-1)N r +m,m=1,…,N r 、n=1,…,N c , represents the selection constraint by marking the positions within the exclusion zone with 1, while the positions outside the zone remain zero, i.e.:

[0107]

[0108] (5.6) For a partially connected electrically controlled movable antenna array, only one candidate antenna can be selected from each electrically controlled movable antenna. Right now in, represents the antenna selection constraint matrix under the partially connected architecture, expressed as [Q] :,s =vec{C p,q}, s=(q-1)M r +p,p=1,…,M r ,q=1,…,M c , The antenna selection constraints in the partially connected architecture are characterized by marking the candidate antenna positions located at the p-th row and q-th column with 1, while all other positions remain zero, i.e.:

[0109]

[0110] (5.7) Under the constraints of transmit power and antenna selection, antenna selection and multi-user beamforming are designed to maximize multi-user communication and rate. According to (5.2), (5.3), (5.4), (5.5), and (5.6), the optimization problem is:

[0111]

[0112] t∈Φ P orΦ F

[0113] Among them, Φ P Including the constraints in (5.3), (5.4), (5.5) and (5.6), Φ F Contains the constraints in (5.3), (5.4), and (5.5).

[0114] (5.8) Solve the antenna selection and multi-user beamforming problem in (5.7) as follows:

[0115] (5.8.1) By taking advantage of the property that any non-trivial stationary point of the beamforming matrix F that maximizes multi-user communication and rate will satisfy the equal power constraint, we can remove the power constraint and simplify the problem to obtain the new optimization problem:

[0116]

[0117] stt∈Φ P orΦF

[0118] in, It can be expressed as:

[0119]

[0120] (5.8.2) The objective function at this time As a non-convex objective function, it can be transformed into an equivalent form:

[0121]

[0122] stt∈Φ P orΦ F

[0123] Among them, e k Defined as:

[0124]

[0125] Among them, u k is the receiving factor of the kth user.

[0126] (5.8.3) In addition, consider the feasible set Φ P and Φ F The antenna selection constraints in the .txt file are processed as follows:

[0127] ①Use the equivalent continuity equation to deal with Φ P and Φ F Binary constraints in [t] p ∈{0,1}, expressed as:

[0128] [t] p (1-[t] p )=0,forp=1,2,…,N t

[0129] ②At this point, a penalty-based approach is used to relax the equality constraint and incorporate it into the objective. The optimization problem is rewritten as:

[0130]

[0131] [t] p ∈[0,1],forp=1,2,…,N t

[0132] The weighted sum of the original objective function and the penalty term of the relaxed constraint is given by:

[0133]

[0134] Among them, ρ1>0, ρ2>0 and ρ3>0 are penalty coefficients for controlling constraint relaxation and preserving the inequality constraints and additional binary constraints [t] p ∈[0,1] to further refine the feasible domain.

[0135] (5.8.4) Based on the above optimization problem, antenna selection and multi-user beamforming are obtained. The specific steps are as follows:

[0136] ① Initialize the penalty coefficients ρ1=1, ρ2=1, ρ3=1, and set the scaling factors β1>1, β2>1, β3>1.

[0137] ② Initialize antenna selection and multi-user beamforming. Assuming that all antennas are selected in the initial state, the antenna selection vector t can be expressed as:

[0138]

[0139] The beamforming matrix is initialized based on the given channel state information. The beamforming matrix can be expressed as:

[0140] F=H

[0141] ③ While keeping other variables unchanged, optimize u k , then the problem can be expressed as:

[0142]

[0143] By making the objective function The partial derivative is zero, and the optimal solution is obtained:

[0144]

[0145] where f i represents the i-th column of F.

[0146] ④ While keeping other variables unchanged, optimize v k , then the problem can be expressed as:

[0147]

[0148] By letting the objective function be k The partial derivative is zero, and the optimal solution is obtained:

[0149]

[0150] ⑤ While keeping other variables unchanged, optimize f k , then the problem can be expressed as:

[0151]

[0152] Calculate the objective function The gradient of can be obtained:

[0153]

[0154] in, By order is zero, the optimal solution is:

[0155]

[0156] Get the optimized beamforming matrix

[0157] ⑥ While keeping other variables unchanged, optimize t. The problem can be expressed as:

[0158]

[0159] Here, ∝ means "proportional" and the terms irrelevant to the optimization variables are omitted. k , the optimization problem can be rewritten as:

[0160]

[0161] in, In order to facilitate further analysis, we define ⊙ represents the Hadamard product, and the optimization problem can be rewritten as:

[0162]

[0163] definition:

[0164]

[0165] Therefore, the optimization problem can be transformed into:

[0166]

[0167] When U is a positive definite matrix, the optimization problem is a convex quadratic programming problem, which can be solved directly using the CVX toolbox; when U is a non-positive definite matrix, the objective function is a non-convex objective function, which can be solved using optimization methods such as the interior point method. Thus, the antenna selection vector is obtained

[0168] ⑦ Iteratively update the penalty coefficients ρ1, ρ2, and ρ3, gradually increasing the penalty coefficients by multiplying these coefficients by the proportional factors β1, β2, and β3, that is:

[0169] ρ1←ρ1β1,ρ2←ρ2β2,ρ3←ρ3β3

[0170] ⑧ Set the threshold Y to determine whether the antenna is selected, which can be expressed as:

[0171]

[0172] That is When , it means the antenna is selected. Iterate steps ③-⑦ until the number of selected antennas equals N s .

[0173] ⑨Get the optimal antenna selection vector After that, reconsider the power constraint, and the optimization problem is:

[0174]

[0175] The above optimization problem is a problem of maximizing the multi-user communication sum rate, which can be effectively solved using the weighted minimum mean square error method, and the obtained maximized multi-user communication sum rate is expressed as V.

[0176] (5.8.5) Based on the solution of the above optimization problem, we get the antenna selection vector As well as multi-user communication and rate V, the coordinate descent method is used to further improve the system performance. The specific steps are as follows:

[0177] ① In the dth iteration, the antenna selection vector is initialized to And select the nth candidate antenna for evaluation, denoting its index as I n , and n=mod(d-1,N s )+1. Then, deactivate the first n antennas, i.e. And evaluate all N in turn t candidate antennas, when evaluating the pth antenna, the updated selection vector is

[0178] ② When evaluating the pth antenna, first determine Whether the feasible set Φ is satisfied P or Φ F If the requirements are met, the optimization problem can be established as:

[0179]

[0180] The weighted minimum mean square error method is used to solve the problem, and the obtained maximum multi-user communication rate is expressed as V p If the requirements are not met, V p = 0. Evaluate all N t After candidate antennas are generated, the index of the antenna with the maximum multi-user communication rate is determined as The corresponding sum rate of the d-th iteration is expressed as The index I of the nth candidate antenna n Updated to

[0181] ③Iterate steps ①② until the d>N s ,n=1,2,…,N s , when converged, maximizing multi-user communication and rate is also optimized to

[0182] The present invention is further described below in conjunction with simulation conditions and results:

[0183] Figure 2 This is a schematic diagram of multi-user communication and rate changes with antenna position intervals under different architectures simulated by a uniform linear array according to an embodiment of the present invention. Under a uniform linear array, the number of antennas in the column direction is 1, that is, N r =1, the number of candidate antennas in each electrically controlled movable antenna ranges from 2 to 20, corresponding to a position interval of λ / 2 to λ / 20. The number of selected antennas N s =4, signal-to-noise ratio SNR = 10dB, number of service users K = 4, each user has L k = 6 channel paths. As can be seen from the figure, as the position spacing decreases, the fully connected architecture gradually approaches the performance of the mechanically movable antenna array in reference [2]. However, when the position spacing is reduced to above λ / 8, it will lead to marginal improvement, indicating that refining the position spacing above λ / 8 provides limited practical benefits in terms of enhancing the multi-user summation rate.

[0184] Figure 3 This is a schematic diagram of multi-user communication with different architectures and rate changes with antenna position spacing under a uniform planar array simulated by an embodiment of the present invention. Extending from the uniform linear array analysis to the uniform planar array, the number of candidate antennas per row and column in each electrically controlled movable antenna ranges from 2 to 9, corresponding to position spacings from λ / 2 to λ / 9. The number of selected antennas N S =4, signal-to-noise ratio SNR = 10dB, number of service users K = 4, each user has L k = 6 channel paths. As can be seen from the figure, the mechanically movable antenna array, the fully connected architecture, and the partially connected architecture perform better. In contrast, the fixed antenna architecture has similar performance for both arrays. Furthermore, as the positional separation decreases, the fully connected architecture gradually approaches the performance of the mechanically movable antenna array, demonstrating the effectiveness of the proposed method.

[0185] Figure 4This is a schematic diagram of multi-user communication and rate variation with signal-to-noise ratio under different architectures simulated in a uniform planar array according to an embodiment of the present invention. Under a uniform planar array, each row and column of the antenna array has 8 candidate antennas, and the number of selected antennas N S =4, the number of service users K = 4, each user has L k = 6 channel paths. As can be seen from the figure, as the signal-to-noise ratio increases, the gap between the mechanically movable antenna array and the fully connected architecture gradually widens, while the gap between the fully connected architecture and the fixed antenna architecture grows even faster. Furthermore, the fully connected architecture consistently approaches the performance of the mechanically movable antenna array under different signal-to-noise ratio conditions, demonstrating the effectiveness of the proposed method.

[0186] Figure 5 This is a schematic diagram of multi-user communication with different architectures and rate changes with the number of paths under the uniform planar array simulated by an embodiment of the present invention. Under the uniform planar array, each row and column of the antenna array has 8 candidate antennas, and the number of selected antennas N S =4, signal-to-noise ratio (SNR) = 10dB. As can be seen from the figure, as the number of paths increases, the performance of the mechanically movable antenna array, fully connected architecture, and partially connected architecture gradually improves, indicating that these methods can more easily identify favorable antenna positions for multi-user communication.

[0187] Figure 6 This is a schematic diagram of multi-user communication with different architectures and rate changes with the number of users under the uniform planar array simulated by the embodiment of the present invention. Under the uniform planar array, the antenna array has 18 candidate antennas per row and 12 candidate antennas per column. The number of selected antennas N S =6, signal-to-noise ratio SNR = 10dB, each user has L k = 6 channel paths. As the figure shows, as the number of users increases, the gap between the mechanically movable antenna array and the fully connected architecture gradually widens, while the gap between the fully connected architecture and the fixed antenna architecture grows even faster. This indicates that greater antenna placement flexibility enhances user communication performance, especially in complex scenarios with a large number of users.

[0188] from Figures 2 to 6 A consistent trend emerged across the data, with the mechanically movable antenna array achieving the best performance, followed by the fully connected architecture, partially connected architecture, and fixed antenna architecture. This performance ranking is consistent with the level of design flexibility; while the fully connected architecture does not reach the exact same level as the mechanically movable antenna array, it remains close in various cases, demonstrating its potential as a practical alternative with significantly reduced complexity.

[0189] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code. The scheme in the embodiment of the present application can be implemented in various computer languages, for example, object-oriented programming language Java and literal translation scripting language JavaScript, etc.

[0190] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0191] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0192] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions for executing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The steps for the function specified in one or more boxes.

[0193] Although the preferred embodiments of the present application have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present application.

[0194] Obviously, those skilled in the art may make various changes and modifications to this application without departing from the spirit and scope of this application. Thus, if these modifications and variations of this application fall within the scope of the claims of this application and their equivalents, this application is intended to include these modifications and variations.

Claims

1. A design of an electrically controlled movable antenna array and a multi-user communication method, characterized in that: The method comprises the following steps: An electrically controlled movable antenna is constructed based on a reconfigurable pixel antenna. The electrically controlled movable antenna constructs a set of predefined and positionally discrete selectable candidate antennas by controlling the states of the RF components interconnected between the pixel antennas. Arrange multiple electrically controllable movable antennas and directly connect them one-to-one with multiple radio frequency links to construct a partially connected electrically controllable movable antenna array, where each radio frequency link selects an antenna from a set of candidate antennas of the connected electrically controllable movable antennas for transmission; An electrically controlled movable antenna is expanded and connected to a radio frequency link through a switch network to construct a fully connected electrically controlled movable antenna array. Each radio frequency link in the fully connected electrically controlled movable antenna array has the ability to connect to all candidate antennas. By dynamically controlling the state of the radio frequency components between pixel antennas, one or more candidate antennas are selected and connected to the radio frequency link. A base station using a partially connected electrically controlled movable antenna array or a fully connected electrically controlled movable antenna array communicates with K single-antenna users. Under transmit power constraints and antenna selection constraints, antenna selection and multi-user beamforming are designed to maximize multi-user communication and data rate. The antenna selection and multi-user beamforming problems are: t∈Φ P orφ F Among them, R k represents the communication sum rate of the kth user; represents the multi-user transmit beamforming matrix; It is represented as the vector representation of the antenna selection matrix T; P represents the maximum allowed transmit power; Φ P represents the feasible set of antenna selections under the partially connected architecture, Φ F represents the feasible set of antenna selection under the fully connected architecture.

2. The electrically controlled movable antenna array design and multi-user communication method according to claim 1, characterized in that: The reconfigurable pixel antenna is composed of multiple pixel antennas, which are connected by radio frequency components. By controlling the state of the radio frequency components between the pixel antennas, the antenna radiation pattern is changed to adjust the equivalent electric center of the antenna array and physically change the position of the antenna array.

3. The electrically controlled movable antenna array design and multi-user communication method according to claim 1, characterized in that: The process of designing antenna selection and multi-user beamforming with the goal of maximizing multi-user communication and rate while satisfying transmit power constraints and antenna selection constraints includes the following steps: Setting corresponding multi-user communication system parameters based on a partially connected electrically controlled movable antenna array architecture and a fully connected electrically controlled movable antenna array architecture; Based on the Saleh-Valenzuela model, the channel transmission models for the partially connected electrically controlled movable antenna array architecture and the fully connected electrically controlled movable antenna array architecture are designed respectively. While satisfying the transmission power constraints and antenna selection constraints, the goal is to maximize multi-user communication and rate. The antenna selection and multi-user beamforming problems are established and solved, and the antenna selection and multi-user beamforming are designed.

4. The electrically controlled movable antenna array design and multi-user communication method according to claim 3, characterized in that: The channel transmission model of the partially connected electrically controlled movable antenna array and the fully connected electrically controlled movable antenna array is: Among them, h k represents the channel vector between the base station and the kth user, N t Indicates the total number of antennas in the antenna array, L k Indicates the number of paths, and denote the channel gain, azimuth angle and elevation angle of the lth path respectively; represents the array steering vector; in The coordinates of the candidate antenna located at the mth row and nth column are expressed as [x n ,0,z m ]; For a partially connected electrically controlled movable antenna array, assuming that the candidate antenna is located at the sth row and tth column of the electrically controlled movable antenna at the pth row and qth column, x n and z m Expressed as: x n =(M c -q)d e +(S c -t)d c ,z m =(M r -p)d e +(S r -s)d c where d c represents the interval between adjacent candidate antennas, d e Represents the spacing between adjacent electrically controlled movable antennas, M r and M c denote the number of rows and columns of the partially connected electrically controlled movable antenna array, S r and S c Respectively represent the number of candidate antenna rows and columns supported by each electrically controlled movable antenna; For a fully connected electrically controlled movable antenna array, x n and z m Expressed as: x n =(N c -n)d c ,z m =(N r -m)d c where N c and N r They represent the number of candidate antenna rows and columns of the fully connected electrically controlled movable antenna array.

5. The electrically controlled movable antenna array design and multi-user communication method according to claim 4, characterized in that: Feasible set of antenna selection under partially connected electrically controlled movable antenna array architecture Φ P It is composed of a vector t that satisfies the following requirements: ①[t] p ∈{0,1},p=1,2,...,N t ,② ③ ④ Feasible set Φ for antenna selection under fully connected electrically controlled movable antenna array architecture F It is composed of a vector t that satisfies the following requirements: ① [t] p ∈{0,1},p=1,2,...,N t ,② ③ in, Represents the spacing constraint matrix, denoted as [S] :,s =vec{B m,n }, s=(n-1)N r +m,m=1,…,N r 、n=1,…,N c , represents the selection constraint by marking the positions within the exclusion zone with 1, while the positions outside the zone remain zero, i.e.: It represents the antenna selection constraint matrix under the partially connected electrically controlled movable antenna array architecture, expressed as [Q] :,s =vec{C p,q }, s=(q-1)M r +p,p=1,…,M r ,q=1,…,M c , The antenna selection constraints in the partially connected electrically controllable movable antenna array architecture are characterized by marking the candidate antenna positions located in the p-th row and q-th column with 1, while all other positions remain zero, that is:

6. The electrically controlled movable antenna array design and multi-user communication method according to claim 5, characterized in that: The process of solving the antenna selection and multi-user beamforming problem includes the following steps: In step S41, the power constraint is removed from the antenna selection and multi-user beamforming problem by utilizing the property that any non-trivial stationary point of the beamforming matrix F that maximizes multi-user communication and rate will satisfy the equal power constraint. The new optimization problem is: s.t.t∈Φ P orφ F in, Expressed as: in diag{·} represents the diagonalization of a vector; Step S42: The objective function Converted to equivalent form: s.t.t∈φ P orΦ F Among them, e k Defined as: Among them, u k is the receiving factor of the kth user; Step S43: For the feasible set Φ P and Φ F The switching network constraints in the .NET framework are processed as follows: Step S431, using the equivalent continuous equation to process Φ P and Φ F Binary constraints in [T] m,n ∈{0,1}, expressed as: [t] p (1-[t] p )=0,forp=1,2,…,N t Step S432: Use a penalty-based method to relax the equality constraint and incorporate it into the objective, rewriting the optimization problem as follows: [t] p ∈[0,1],forp=1,2,…,N t in, represents the weighted sum of the original objective function and the penalty term of the relaxed constraint; Step S44: Solve the above optimization problem to obtain antenna selection and multi-user beamforming.

7. An electrically controlled movable antenna array, characterized in that: The electrically controlled movable antenna array includes a partially connected electrically controlled movable antenna array and a fully connected electrically controlled movable antenna array; The partially connected electrically controlled movable antenna array is constructed by arranging multiple electrically controlled movable antennas and directly connecting them one-to-one with multiple radio frequency links. Each radio frequency link selects one antenna from a set of connected candidate antennas for transmission. The fully connected electrically controlled movable antenna array is constructed by extending one electrically controlled movable antenna and connecting it to radio frequency links through a switch network. Each radio frequency link has the ability to connect to all candidate antennas. One or more candidate antennas are selected and connected to the radio frequency links by dynamically controlling the state of radio frequency components between pixel antennas. Each electrically controlled movable antenna is composed of multiple pixel antennas, which are connected by radio frequency components. By controlling the state of the radio frequency components between the pixel antennas, the antenna radiation pattern is changed to adjust the equivalent electrical center of the antenna array and physically change the position of the antenna array. The electrically controlled movable antenna array selects a partially connected electrically controlled movable antenna array or a fully connected electrically controlled movable antenna array as a base station for communication with K single-antenna users. Under the conditions of satisfying transmit power constraints and antenna selection constraints, with the goal of maximizing multi-user communication and rate, antenna selection and multi-user beamforming are designed using the method described in any one of claims 1 to 6.

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