Method and system for improving array effective degree of freedom of asynchronous regulation and control metasurface antenna

Abstract

The invention relates to a method and a system for improving the effective degree of freedom of an array of an asynchronous regulation metasurface antenna, and the method comprises the steps: designing the state switching starting time of different electromagnetic units through the characteristic that the regulation starting time of the different electromagnetic units of the metasurface antenna can be independently controlled, so as to enable the states of the electromagnetic units to be arranged in a staggered manner; the effective degree of freedom of the antenna array is improved under the condition that the switching rate of the electromagnetic units of the metasurface antenna is not changed.

Description

Technical Field

[0001] The present invention relates to the field of antennas, and in particular to a method and system for improving the effective degree of freedom of an array of asynchronously controlled metasurface antennas. Background Art

[0002] Antenna arrays are the foundation for multi-stream information multiplexing. Utilizing Multiple-Input Multiple-Output (MIMO) technology, multiple antennas are deployed at both the transmit and receive ends, leveraging channel differences between antenna elements to achieve spatial diversity and multiplexing, thereby increasing system communication capacity. The maximum number of spatially multiplexed signal streams a system can achieve is determined by the effective degrees of freedom of the antenna array. However, the number of antenna elements and the number of RF channels in an antenna array jointly determine the effective degrees of freedom. Traditional single-RF link antenna arrays have an effective degree of freedom of 1, making them incapable of receiving and separating multi-stream signals.

[0003] The recent emergence of metasurface antennas has provided a new approach for improving the effective degrees of freedom of arrays within a single RF link. Metasurface antennas are a new type of reconfigurable antenna, composed of a large number of low-cost, reconfigurable electromagnetic elements made of metamaterials combined with an RF link. Metasurface antennas leverage the reconfigurable nature of their electromagnetic elements to rapidly and flexibly adjust the amplitude, phase, polarization, and other characteristics of the incident signal. Compared to traditional antennas, metasurface antennas can achieve multiple differentiated receptions by changing the state of the electromagnetic elements at the receiving end multiple times within a single symbol period, achieving multi-channel data reception within a single RF channel and reducing receiver hardware design costs and deployment difficulties. The greater the number of electromagnetic elements in a metasurface, the larger the antenna array that can be simulated, increasing the effective degrees of freedom of the array. However, the switching rate of the electromagnetic element states in a metasurface antenna limits its effectiveness in improving the effective degrees of freedom of the array. If a metasurface antenna cannot switch the number of electromagnetic element states required by the number of elements within a symbol period, it will not reach the upper limit of the effective degrees of freedom of the array. In addition, with the growth of communication rate and the increase in the number of metasurface units, it is difficult to switch the number of electromagnetic unit states to the number of electromagnetic units within one symbol period, and the full potential of the metasurface antenna cannot be realized. Summary of the Invention

[0004] In view of the problem that the metasurface antenna in the prior art cannot switch to a state equal to the number of metasurface electromagnetic units within one symbol period due to factors such as the limited switching rate of the electromagnetic units and the high communication rate, thereby failing to further improve the effective degrees of freedom of the array, the present invention provides a method for improving the effective degrees of freedom of the array of asynchronously controlled metasurface antennas to achieve the upper limit of the effective degrees of freedom of the array, the method comprising:

[0005] Step 1: Calculate the effective degree of freedom of the array, γ, where γ = [N / K m], N is the number of metasurface electromagnetic units;

[0006] Step 2: Calculate the starting time t for switching between different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (γ·K m ), where q n =mod(n,γ)-1, mod(n,Υ) represents the remainder of n and Υ. When mod(n,Υ)=0, q n =Y-1;

[0007] Step 3: Calculate the metasurface electromagnetic unit state weight matrix W a ; Among them, the electromagnetic unit state weight matrix W a Internal element relationships are expressed as:

[0008]

[0009] in, If n+Υp>N, then k=n+Υp-N, when k+Υ-1>N, becomes

[0010] Optionally, the effective degree of freedom of the synchronously controlled array is increased to an upper limit K m K should be satisfied m ≥2.

[0011] Optionally, asynchronous control is introduced to increase the effective degree of freedom of the array by a multiple of Y = [N / K m ], where [N / K m ] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

[0012] Optionally, when the metasurface antenna adopts a point control form, n represents the nth metasurface electromagnetic unit; when the metasurface antenna adopts a column control form, n represents all electromagnetic units in the nth column of the metasurface antenna.

[0013] Optionally, the metasurface electromagnetic unit state weighting matrix W a represents the different receiving characteristics of the metasurface antenna for the same signal within one symbol period, ω a (i) represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period, Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

[0014] In a second aspect of the present invention, a system for improving the effective degrees of freedom of an array of asynchronously controlled metasurface antennas is provided, the system comprising:

[0015] The improvement factor calculation module is used to calculate the improvement factor γ of the effective degree of freedom of the array; where γ=[N / K m ], N is the number of metasurface electromagnetic units.

[0016] The electromagnetic unit switching time calculation module is used to calculate the starting time t of the switching of different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (Υ·K m ), where q n =mod(n,Υ)-1, mod(n,γ) represents the remainder of n and γ. When mod(n,γ)=0, q n =γ-1.

[0017] Weighted matrix calculation module, used to calculate the metasurface electromagnetic unit state weighted matrix W a ; Among them, the electromagnetic unit state weight matrix W a Internal element relationships are expressed as:

[0018]

[0019] in, If n+Υp>N, then k=n+Υp-N, when k+γ-1>N, becomes

[0020] Preferably, the effective degree of freedom of the synchronously controlled array is increased to an upper limit K m K should be satisfied m ≥2.

[0021] Preferably, the introduction of asynchronous control increases the multiple of the array's effective degree of freedom γ = [N / K m ], where [N / K m ] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

[0022] Preferably, when the metasurface antenna adopts a point control form, n represents the nth metasurface electromagnetic unit; when the metasurface antenna adopts a column control form, n represents all electromagnetic units in the nth column of the metasurface antenna.

[0023] Preferably, the metasurface electromagnetic unit state weighting matrix Wa represents the different receiving characteristics of the metasurface antenna for the same signal within one symbol period, ω a (i) represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period, Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

[0024] The present invention designs the starting time of the electromagnetic unit states of the metasurface antenna so that different electromagnetic unit states are staggered within a symbol period, thereby further improving the effective degrees of freedom of the array and enhancing the multi-stream information multiplexing capability. By staggering different electromagnetic unit states within a symbol period, the effective degrees of freedom of the antenna array are improved without changing the state switching rate of the electromagnetic unit states of the metasurface antenna. Under the same metasurface electromagnetic unit state switching rate, more effective degrees of freedom of the array can be improved, and a lower metasurface electromagnetic unit state switching rate can be used when the same effective degrees of freedom of the array is improved. This reduces the demand for the state switching rate of the electromagnetic unit states of the metasurface and places lower demands on the device. In addition, the present invention is designed based on a metasurface antenna with a single radio frequency link, has the advantages of low manufacturing cost and ease of deployment, making it easy to promote and apply. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 This is an application scenario of the embodiment;

[0026] Figure 2 is a flow chart of an embodiment;

[0027] Figure 3 This is the schematic diagram of asynchronous control. DETAILED DESCRIPTION

[0028] In the embodiments of the present invention, words such as "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in the embodiments of this application should not be construed as being preferred or advantageous over other embodiments or designs. Rather, the use of words such as "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner to facilitate understanding.

[0029] It will be understood that the “embodiment” mentioned throughout the specification means that the specific features, structures or characteristics related to the embodiment are included in at least one embodiment of the present application. Therefore, the various embodiments throughout the specification do not necessarily refer to the same embodiment. In addition, these specific features, structures or characteristics can be combined in one or more embodiments in any suitable manner. It will be understood that in the various embodiments of the present application, the size of the sequence number of each process does not mean the order of execution. The execution order of each process should be determined by its function and internal logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0030] In the present invention, unless otherwise specified, the same or similar parts between the various embodiments can refer to each other. In the various embodiments of the present invention, and the various implementation methods / implementation methods / implementation methods in each embodiment, if there is no special explanation and logical conflict, the terms and / or descriptions between different embodiments and the various implementation methods / implementation methods / implementation methods in each embodiment are consistent and can be referenced to each other. The technical features in different embodiments and the various implementation methods / implementation methods / implementation methods in each embodiment can be combined to form new embodiments, implementation methods, implementation methods, or implementation methods according to their inherent logical relationships. The implementation methods of the present application described below do not constitute a limitation on the scope of protection of the present application.

[0031] Since asynchronous control is achieved by designing the starting time of switching between different electromagnetic unit states, the essence of asynchronous control to improve the effective freedom of the array is the staggered arrangement of the electromagnetic unit states within one symbol.

[0032] In one embodiment, the present invention can be applied to Figure 1 In the multi-stream signal reception scenario shown in FIG. 1 , the metasurface antenna is composed of N electromagnetic units arranged uniformly and linearly, each of which contains a controllable electromagnetic element. The phase parameters of the transmitted and received signals can be controlled by changing the state of the element. The antenna is placed in a Cartesian coordinate system, where O φ is the origin of the coordinate system, g n Represents the position vector of the metasurface unit n. e l represents the unit vector of the lth signal arrival path. l The angle with the normal direction is θ. At this time, the receiving phase of the path l at unit n can be expressed as:

[0033]

[0034] Where λ is the carrier wavelength of the arriving signal, |·| is the vector modulus, <g n ,e l > represents g n In e lThe projection length in the direction. Assume that the control of each electromagnetic unit of the metasurface antenna on the arrival signal can be expressed as ω n Then the receiving response of the metasurface antenna to the path l can be expressed as:

[0035]

[0036] Assume that the signal sent by the metasurface goes through L multipaths to reach the receiving end. The unit vector of L multipaths can be expressed as e l ,…,e L , then the receiving response of the metasurface antenna to all multipaths can be expressed as:

[0037]

[0038] Where ω=(ω1…ω N ) T represents the adjustable configuration parameters of the metasurface antenna, G=(g1g N ) represents the position vector of each element of the metasurface antenna. E=(e1e L ) represents the unit vector of all multipaths. Assume that there are M streams sending signals x=(x1,…,x M ) T , the complex gain of each multipath channel is expressed as α l =(α1,…,α M ) T The RF link noise is represented by z~CN(0,σ 2 ). The signal received by the metasurface antenna can be expressed as:

[0039]

[0040] Since the switching rate of electromagnetic units can reach the microsecond level, the metasurface antenna can quickly switch the electromagnetic unit state within a symbol period to achieve a single-channel RF link antenna simulating a multi-channel array receiving signal, thereby improving the array's effective degrees of freedom. The metasurface antenna switches the electromagnetic unit state at intervals of Δτ. Assuming that the multipath remains unchanged within a symbol period, the metasurface antenna switches a total of K groups of unit states. The received signal can be expressed as:

[0041]

[0042] In the above formula Represents the state combination of the electromagnetic units of the metasurface antenna at time k. The state combination of the electromagnetic units of the metasurface within a symbol period can be expressed as the matrix W = (ω (1) ...ω (K) ) TAt this time, the effective degree of freedom of the metasurface antenna receiving signal array is increased from one dimension to K dimensions, that is, the single RF link metasurface antenna simulation is simulated as a K-dimensional antenna array receiving signal through the rapid switching of the electromagnetic unit state.

[0043] Assume that the maximum state switching rate of the electromagnetic unit of the metasurface antenna is v m =1 / Δτ m , Δτ m The minimum duration of each electromagnetic unit state. If all electromagnetic units are synchronously controlled, in one symbol period T B The maximum number of electromagnetic unit state combinations that can be obtained within K m =T B / Δτ m =v m ·T B At this time, the electromagnetic unit state of the metasurface antenna in one symbol period can be expressed as the matrix W m :

[0044]

[0045] When the state switching rate of the electromagnetic unit of the metasurface antenna is limited, the number of electromagnetic units switched in one symbol period is K. m When the number of metasurface units N cannot be reached, the effective degrees of freedom of the array improved by the metasurface antenna cannot reach the performance upper limit.

[0046] Next, according to the asynchronous control metasurface multi-stream signal receiving method of the present invention, it is possible to switch out N or more electromagnetic unit state combinations within one symbol period, reaching the upper limit of the effective degree of freedom of the array, such as Figure 2 The specific steps are as follows:

[0047] Step 1: Calculate the effective degree of freedom of the array to increase by a factor of γ. Due to the limitation of the state switching rate of the electromagnetic unit, the traditional synchronous control method is limited to one symbol period T. B Only K can be reached within m The switching of the sub-electromagnetic unit state, that is, the upper limit of the effective degree of freedom of the synchronously controlled array is K m Without changing the state switching rate of the electromagnetic unit, the introduction of asynchronous control increases the multiple of the array's effective degree of freedom γ=[N / K m ], N is the number of metasurface electromagnetic units.

[0048] Step 2: Calculate the starting time t for switching between different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (γ·Km ), q n =mod(n,γ)-1. mod(n,γ) represents the remainder of n and γ. When mod(n,γ)=0, q n =γ-1.

[0049] Step 3: Calculate the metasurface electromagnetic unit state weight matrix W a Since asynchronous control is achieved by designing the starting time of switching between different electromagnetic unit states, the essence of asynchronous control to improve the effective degree of freedom of the array is the staggered arrangement of electromagnetic unit states within a symbol. Then the electromagnetic unit state weighting matrix W a The internal element relationship can be expressed as:

[0050]

[0051] in, p=0,1,…,K m -1, if n+γp>N, then k=n+γp-N. When k+γ-1>N, the above formula becomes

[0052] After obtaining the state weighted matrix of the metasurface electromagnetic unit, flexible control and design can be used to achieve precise manipulation of the electromagnetic beam in space, thereby realizing functions such as beamforming, multi-beam generation, space division multiplexing, interference suppression and adaptive adjustment, thereby achieving an increase in the effective degrees of freedom of the metasurface antenna array in the spatial domain. Figure 3 It shows that when N=9, K m =3 when asynchronous control principle diagram.

[0053] At this time, the metasurface antenna receiving signal model can be expressed as follows:

[0054]

[0055] After asynchronous control, the number of electromagnetic unit state combinations that appear in one symbol period becomes γ·K m ≥N, reaching the upper limit of the effective degree of freedom of the array under this number of electromagnetic units. The state of the electromagnetic unit in one symbol period is represented by the matrix W a , array manifold matrix The product of the channel complex gain matrix α is expressed as the equivalent channel matrix In multi-stream signal separation, the rank of the equivalent channel matrix H represents the maximum number of separable signal streams, and the condition number κ(H) of the equivalent channel matrix H represents the quality of signal separation performance, namely:

[0056]

[0057] When the condition number of the channel matrix is smaller, it means that the quality of each sub-channel of the channel matrix is closer, and the bit error rate of the separated signal is lower. Therefore, in order to achieve the best multi-stream signal separation reception effect, we can minimize the condition number of the equivalent channel matrix H as the optimization goal and calculate the weight matrix W of the asynchronous metasurface electromagnetic unit state matrix a The optimization problem can be expressed as:

[0058]

[0059] in According to the asynchronous control law, we have:

[0060]

[0061] where k = n + Υp, p = 0, 1, ..., K m -1, if n+Υp>N, then k=n+Υp-N. Assume that the array manifold matrix is The above problem can be solved by using intelligent optimization algorithms such as genetic algorithms and particle swarm optimization to obtain the global optimal solution. Alternatively, the problem can be relaxed using optimization theory and converted to a non-convex problem to obtain a closed-form solution.

[0062] Furthermore, the effective degree of freedom of the array controlled synchronously in step 1 is increased to an upper limit K m K should be satisfied m ≥2, the asynchronous control method can be used to further improve the effective degree of freedom of the array, otherwise spectrum aliasing will occur.

[0063] Furthermore, the introduction of asynchronous control increases the multiple of the array's effective degree of freedom γ = [N / K m ], where [N / K m ] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

[0064] Furthermore, in step 2, when the metasurface antenna adopts point control, n represents the nth metasurface electromagnetic unit. When the metasurface antenna adopts column control, n represents all electromagnetic units in the nth column of the metasurface antenna.

[0065] Furthermore, the metasurface electromagnetic unit state weighting matrix W in step 3 is a Represents the different reception characteristics of the metasurface antenna for the same signal within a symbol period. a (i) It represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period. Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

[0066] Furthermore, the metasurface electromagnetic unit state weighting matrix W in step 3 is a The state design objectives should be determined by the reception purpose. For example, when multi-stream signal separation is required, the matrix formed by the electromagnetic unit state combination within a symbol period should be as compatible as possible with the array manifold matrix and the channel complex gain to achieve optimal multi-stream information reception. When performing multipath sensing, the correlation between the state combinations of different metasurface electromagnetic units should be minimized.

[0067] In a second aspect of the present invention, a system for improving the effective degrees of freedom of an array of asynchronously controlled metasurface antennas is provided, the system comprising:

[0068] The improvement factor calculation module is used to calculate the improvement factor γ of the effective degree of freedom of the array; where γ=[N / K m ], N is the number of metasurface electromagnetic units.

[0069] The electromagnetic unit switching time calculation module is used to calculate the starting time t of the switching of different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (γ·K m ), where q n =mod(n,γ)-1, mod(n,γ) represents the remainder of n and γ. When mod(n,γ)=0, q n =γ-1.

[0070] Weighted matrix calculation module, used to calculate the metasurface electromagnetic unit state weighted matrix W a ; Among them, the electromagnetic unit state weight matrix W a Internal element relationships are expressed as:

[0071]

[0072] in, If n+γp>N, then k=n+γp-N, when k+γ-1>N, becomes

[0073] Preferably, the effective degree of freedom of the synchronously controlled array is increased to an upper limit K m Meet K m ≥2.

[0074] Preferably, the introduction of asynchronous control increases the multiple of the array's effective degree of freedom γ = [N / K m ], where [N / K m] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

[0075] Preferably, when the metasurface antenna adopts a point control form, n represents the nth metasurface electromagnetic unit; when the metasurface antenna adopts a column control form, n represents all electromagnetic units in the nth column of the metasurface antenna.

[0076] Preferably, the metasurface electromagnetic unit state weighting matrix W a represents the different receiving characteristics of the metasurface antenna for the same signal within one symbol period, ω a (i) represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period, Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

[0077] The above embodiments can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present application is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) method. The computer-readable storage medium can be any available medium that a computer can access or a data storage device such as a server or data center that includes one or more available media integrations. The available medium can be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[0078] The steps of the methods or algorithms described in the embodiments of the present application can be directly embedded in hardware, software units executed by a processor, or a combination of the two. The software units can be stored in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, removable disk, CD-ROM, or other storage media in any form known in the art. Exemplarily, the storage medium can be connected to the processor so that the processor can read information from the storage medium and write information to the storage medium. Alternatively, the storage medium can also be integrated into the processor. The processor and storage medium can be arranged in an ASIC.

[0079] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0080] Although the present application has been described with reference to specific features and embodiments thereof, it is apparent that various modifications and combinations may be made thereto without departing from the spirit and scope of the present application. Accordingly, this specification and the drawings are merely illustrative of the present application as defined by the appended claims and are deemed to cover any and all modifications, variations, combinations or equivalents within the scope of the present application. Obviously, those skilled in the art may make various modifications and variations to the present application without departing from the scope of the present application. Thus, the present application is intended to include such modifications and variations if they fall within the scope of the claims of the present application and their equivalents.

Claims

1. A method for improving the effective degree of freedom of an asynchronously controlled metasurface antenna array, characterized in that: The method comprises: Step 1: Calculate the effective degree of freedom of the array increased by a multiple of Υ; where Υ = [N / K m ], N is the number of metasurface electromagnetic units; Step 2: Calculate the starting time t for switching between different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (Υ·K m ), where q n =mod(n,γ)-1, mod(n,γ) represents the remainder of n and γ. When mod(n,Υ)=0, q n =γ-1; Step 3: Calculate the metasurface electromagnetic unit state weight matrix W a ; Among them, the electromagnetic unit state weight matrix W a Internal element relationships are expressed as: in, k=n+Υp,p=0,1,…,K m -1, if n+γp>N, then k=n+γp-N, when k+Y-1>N, becomes 2. The method according to claim 1, wherein The upper limit K of the effective degree of freedom of the synchronously controlled array is increased m K should be satisfied m ≥2.

3. The method according to claim 1, wherein Introducing asynchronous control to increase the multiple of array effective freedom degree Υ=[N / K m ], where [N / K m ] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

4. The method according to claim 1, wherein When the metasurface antenna adopts point control, n represents the nth metasurface electromagnetic unit; when the metasurface antenna adopts column control, n represents all electromagnetic units in the nth column of the metasurface antenna.

5. The method according to claim 1, wherein Metasurface electromagnetic unit state weight matrix W a represents the different receiving characteristics of the metasurface antenna for the same signal within one symbol period, ω a (i) represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period, Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

6. A system for improving the effective degree of freedom of an asynchronously controlled metasurface antenna array, characterized in that: The system comprises: The improvement multiple calculation module is used to calculate the array effective degree of freedom improvement multiple Υ; where Υ=[N / K m ], N is the number of metasurface electromagnetic units; The electromagnetic unit switching time calculation module is used to calculate the starting time t of the switching of different electromagnetic units of the metasurface antenna n , n=1,2,..,N; the switching start time t of the nth metasurface antenna electromagnetic unit n =(q n ·T B ) / (Υ·K m ), where q n =mod(n,Υ)-1, mod(n,γ) represents the remainder of n and γ. When mod(n,γ)=0, q n =γ-1; Weighted matrix calculation module, used to calculate the metasurface electromagnetic unit state weighted matrix W a ; Among them, the electromagnetic unit state weight matrix W a Internal element relationships are expressed as: in, k=n+γp,p=0,1,…,K m -1, if n+γp>N, then k=n+γp-N, when k+γ-1>N, becomes 7. The system according to claim 6, wherein: The upper limit K of the effective degree of freedom of the synchronously controlled array is increased m K should be satisfied m ≥2.

8. The system according to claim 6, wherein: Introducing asynchronous control to increase the multiple of array effective freedom degree γ=[N / K m ], where [N / K m ] represents the number of metasurface electromagnetic units N and K m After division, the value is rounded up.

9. The system according to claim 6, wherein: When the metasurface antenna adopts point control, n represents the nth metasurface electromagnetic unit; when the metasurface antenna adopts column control, n represents all electromagnetic units in the nth column of the metasurface antenna.

10. The system according to claim 6, wherein: Metasurface electromagnetic unit state weight matrix W a represents the different receiving characteristics of the metasurface antenna for the same signal within one symbol period, ω a (i) represents the combined receiving characteristics of the electromagnetic unit states of the metasurface antenna at time i within a symbol period, Represents the state of the control and reception signal of different electromagnetic units of the metasurface at time i.

Images