Regulation and control method and device for reconfigurable metasurface scattered field and computer program product

Abstract

A reconfigurable metasurface scattered field regulation and control method and device and a computer program product, and the method comprises the steps: selecting a to-be-optimized load impedance vector according to the type of an electromagnetic modulation element in a reconfigurable metasurface, and inputting the to-be-optimized load impedance vector to a scattered field calculation model to obtain real-time scattered field distribution; wherein the scattered field calculation model is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattered field; based on the difference between the real-time scattering field distribution and the target scattering field distribution, a corresponding convex optimization algorithm is adopted in combination with the type of the electromagnetic modulation element, and an optimized load impedance vector is obtained; inputting the optimized load impedance vector into a scattered field calculation model for iteration to obtain a final load impedance vector; and calculating a lumped element parameter of the electromagnetic modulation element based on the final load impedance vector. According to the method, high-precision regulation and control of the reconfigurable metasurface scattered field are ensured, the optimization efficiency is improved, and data dependence is reduced. And high optimization precision and low calculation overhead are both considered.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electromagnetic wave regulation, in particular to a reconfigurable metasurface scattering field regulation method and device and computer program product. BACKGROUND

[0002] Reconfigurable metasurfaces have become an important research direction in the field of electromagnetic wave regulation due to their flexibility and high degree of freedom in scattering control, and are widely used in key engineering scenarios such as intelligent antennas, radar detection and spatial electromagnetic reconstruction. In order to achieve high-performance scattering field design, the regulation of the scattering field as a key link directly determines the practical value and response ability of the reconfigurable metasurface.

[0003] At present, the scattering field regulation method can be mainly divided into two categories: one is based on equivalent circuit or approximate scattering model, which pursues higher optimization efficiency, but it is difficult to accurately describe the far-field response characteristics in the case of multiple incidence and complex coupling; the other relies on data-driven methods based on full-wave simulation, which uses neural networks or evolutionary algorithms to search for control parameters and fit patterns, which has high accuracy but usually relies on large data sets and computing resources.

[0004] That is, the current regulation method of the scattering field is difficult to balance high optimization accuracy and low computational overhead. SUMMARY

[0005] The purpose of the present application is to provide a reconfigurable metasurface scattering field regulation method, device and computer program product. To balance high optimization accuracy and low computational overhead in the regulation process of the scattering field.

[0006] In a first aspect, the present application provides a reconfigurable metasurface scattering field regulation method, comprising: selecting a load impedance vector to be optimized according to the type of electromagnetic modulation element in the reconfigurable metasurface, and inputting the load impedance vector to a model of the scattering field calculation to obtain a real-time scattering field distribution; wherein the model of the scattering field calculation is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattering field; based on the difference between the real-time scattering field distribution and a target scattering field distribution, and combining the type of the electromagnetic modulation element, a corresponding convex optimization algorithm is used to obtain an optimized load impedance vector; inputting the optimized load impedance vector into the model of the scattering field calculation for iteration to obtain a final load impedance vector; and based on the final load impedance vector, calculating the lumped element parameters of the electromagnetic modulation element.

[0007] The reconfigurable metasurface scattering field regulation method regulates the scattering field of the reconfigurable metasurface by establishing a model for scattering field calculation, performing iterative calculation based on a convex optimization algorithm, obtaining a final load impedance vector, and calculating lumped element parameters of the electromagnetic modulation element based on the final load impedance vector, thereby ensuring high-precision regulation of the scattering field of the reconfigurable metasurface, improving optimization efficiency, and greatly reducing data dependence.

[0008] In combination with the first aspect, optionally, the model for scattering field calculation is:

[0009] where θ and φ represent the elevation angle and the azimuth angle of the scattering field, respectively; represents diagonal matrix of a vector; is an M-dimensional vector, representing the scattering field distribution of the reconfigurable metasurface; represents the load impedance of the electromagnetic modulation element; is an M-dimensional vector, representing the scattering field of the reconfigurable metasurface when the load impedance tends to infinity, and M represents the number of samples of the scattering field; is an M×N matrix, N represents the number of reconfigurable units in the reconfigurable metasurface, and the (m, n)th element in the M×N matrix represents the radiation electric field intensity in the mth sampling direction when the nth reconfigurable unit is excited by a unit current; Z is an N×N matrix, and the elements in the N×N matrix represent mutual impedance and self impedance of the reconfigurable units; and v represents the induced voltage on each electromagnetic modulation element of the reconfigurable metasurface when the load impedance tends to infinity.

[0010] The reconfigurable metasurface scattering field regulation method has higher precision, lower data requirement, and flexibility by using the specific scattering field forward calculation model, compared with other models such as full-wave simulation model and equivalent circuit model, and the model provides a general optimization framework for solving continuous (analog modulation element) and discrete electromagnetic modulation element (digital modulation element) optimization problems, thereby realizing unified processing of the reconfigurable metasurfaces corresponding to the two types of electromagnetic modulation elements. Therefore, the optimization efficiency is further improved while the scattering field of the reconfigurable metasurface is regulated with high precision.

[0011] Optionally in combination with the first aspect, the electromagnetic modulation element comprises an analog modulation element; and the selecting the load impedance vector to be optimized according to the type of the electromagnetic modulation element in the reconfigurable metasurface and inputting the load impedance vector to the model of the scattering field calculation to obtain the real-time scattering field distribution comprises: uniformly selecting N complex impedance values between the minimum capacitance value and the maximum capacitance value of the analog modulation element to form an N-dimensional load impedance vector to be optimized; and inputting the load impedance vector to the model of the scattering field calculation to obtain the real-time scattering field distribution.

[0012] In the above method for regulating the scattering field of the reconfigurable metasurface, when the electromagnetic modulation element is an analog modulation element, the method uniformly selects N complex impedance values between the minimum capacitance value and the maximum capacitance value of the analog modulation element to provide a reasonable initial value for iteration using the convex optimization algorithm, thereby improving the efficiency and convergence speed of the iteration algorithm.

[0013] Optionally in combination with the first aspect, the obtaining the optimized load impedance vector based on the difference between the real-time scattering field distribution and the target scattering field distribution and using a corresponding convex optimization algorithm according to the type of the electromagnetic modulation element comprises: The optimized load impedance vector is calculated using the following formula:

[0014] wherein, represents the optimized load impedance vector obtained in the kth iteration; min represents the minimum value, and max represents the maximum value; Re represents the real part of a complex number, and Im represents the imaginary part of a complex number, represents the modulus of a complex number, represents the Euclidean norm of a vector; θ and φ respectively represent the pitch angle and the azimuth angle of the scattering field, and θ0 and φ0 represent the pitch angle and the azimuth angle of the main lobe direction of the scattering field; represents a set of side lobe regions; ω represents the operating angular frequency of an electromagnetic wave; and respectively represent the parasitic resistance value and the parasitic inductance value of the analog modulation element; and respectively represent the minimum capacitance value and the maximum capacitance value of the analog modulation element; represents the maximum difference between corresponding elements in the optimized load impedance vector obtained in the kth iteration and the optimized load impedance vector obtained in the k-1th iteration; represents the gradient value.

[0015] The reconfigurable metasurface scattering field regulation method specifically provides a specific convex optimization method for the purpose of minimizing the sidelobe level in the case that the electromagnetic modulation element is an analog modulation element. The optimization formula of the perturbation theory is introduced to optimize the load impedance vector to be optimized, which can accurately describe the scattering characteristics of electromagnetic waves on the metasurface, thereby further improving the optimization accuracy. Moreover, the data required by the formula is less, thereby further reducing the computational overhead. That is, high optimization accuracy and low computational overhead are better balanced.

[0016] In combination with the first aspect, optionally, the calculation of the lumped element parameter of the electromagnetic modulation element based on the final load impedance vector comprises: calculating the lumped element parameter according to the following formula:

[0017] In the formula, C opt represents the lumped element parameter.

[0018] In the case that the electromagnetic modulation element is an analog modulation element, the calculation formula of the lumped element parameter excludes the influence of the parasitic inductance on the calculation result, so that the calculated lumped element parameter, that is, the capacitance value of each analog modulation element, is more accurate.

[0019] In combination with the first aspect, optionally, the electromagnetic modulation element comprises a digital modulation element; and the selection of the load impedance vector to be optimized according to the type of the electromagnetic modulation element in the reconfigurable metasurface and the input of the real-time scattering field distribution obtained by the model of the scattering field calculation comprises: generating N 0s or 1s with equal probability and independence to constitute an N-dimensional load impedance vector to be optimized; wherein N represents the number of reconfigurable units in the reconfigurable metasurface; and the input of the real-time scattering field distribution obtained by the model of the scattering field calculation.

[0020] In the case that the electromagnetic modulation element is a digital modulation element, N 1s or 0s are generated with equal probability and independence to constitute a load impedance vector to be optimized. Similarly, a more reasonable initial value is provided for iteration by using a convex optimization algorithm, thereby improving the efficiency and convergence speed of the iteration algorithm.

[0021] In combination with the first aspect, optionally, the calculation of the optimized load impedance vector based on the difference between the real-time scattering field distribution and the target scattering field distribution and the type of the electromagnetic modulation element by using a corresponding convex optimization algorithm comprises: calculating the optimized load impedance vector by using the following formula:

[0022] In the formula, c （k） represents the optimized load impedance vector obtained in the kth iteration; min represents minimum value, and max represents maximum value; and θ and φ represent the pitch angle and azimuth angle of the scattering field, respectively, and θ0 and φ0 represent the pitch angle and azimuth angle of the main lobe direction of the scattering field; represents a set of side lobe regions; and λ is a regularization parameter; represents the load impedance, and the relationship between the load impedance and the configuration vector c satisfies the following formula:

[0023] In the formula, c = c （1）… c （k-1）、 c （k） and and respectively represent the parasitic resistance value, the parasitic inductance value and the capacitance value when the digital modulation element is disconnected; represents a gradient value.

[0024] The above method for regulating the scattering field of the reconfigurable metasurface specifically provides a specific convex optimization method in the case that the electromagnetic modulation element is a digital modulation element, optimizes the target of minimizing the side lobe level, ingeniously solves the discrete binary combination optimization problem under the continuous convex optimization framework by introducing a regularization term, and further reduces the calculation overhead due to the smaller amount of data required by the formula. That is, high optimization accuracy and low calculation overhead are better balanced.

[0025] In combination with the first aspect, optionally, the inputting of the optimized load impedance vector into the model for calculating the scattering field for iteration to obtain a final load impedance vector comprises: inputting the optimized load impedance vector into the model for calculating the scattering field for iteration until the number of iterations reaches an iteration number threshold, to obtain the final load impedance vector.

[0026] The above method for regulating the scattering field of the reconfigurable metasurface, due to the characteristics of the convex optimization algorithm, can obtain a physically realizable impedance configuration after interrupting the algorithm after any iteration, and the performance of the configuration is usually better than the result of the previous iteration. Therefore, by pre-allocating a calculation budget for the optimization process and outputting the optimization result when the budget is exhausted, the entire iteration process is converted into a “calculation process” with predictable performance, controllable time consumption and reliable results, so that the regulation of the scattering field of the reconfigurable metasurface is more stable and efficient.

[0027] ​In a second aspect, the application provides a device for regulating a scattering field of a reconfigurable metasurface, comprising: a selection module configured to select a load impedance vector to be optimized according to a type of electromagnetic modulation element in the reconfigurable metasurface, and input the load impedance vector into a model for calculating the scattering field to obtain a real-time scattering field distribution; wherein the model for calculating the scattering field is established based on a relationship between the load impedance of the electromagnetic modulation element and the scattering field; an iteration module configured to obtain an optimized load impedance vector based on a difference between the real-time scattering field distribution and a target scattering field distribution, and in combination with the type of the electromagnetic modulation element, using a corresponding convex optimization algorithm; the iteration module is further configured to input the optimized load impedance vector into the model for calculating the scattering field for iteration to obtain a final load impedance vector; and a calculation module configured to calculate lumped element parameters of the electromagnetic modulation element based on the final load impedance vector.

[0028] The device for regulating the scattering field of the reconfigurable metasurface has the same beneficial effects as the method for regulating the scattering field of the reconfigurable metasurface provided in the first aspect or any one of the optional embodiments of the first aspect, and will not be described here.

[0029] In a third aspect, the application provides a computer program product, comprising computer programs / instructions which, when executed by a processor, implement the method described above.

[0030] The computer program product has the same beneficial effects as the method for regulating the scattering field of the reconfigurable metasurface provided in the first aspect or any one of the optional embodiments of the first aspect, and will not be described here. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the application, the following will briefly introduce the drawings needed to be used in the embodiments of the application. It should be understood that the following drawings only show some embodiments of the application, and therefore should not be regarded as a limitation on the scope, and for those skilled in the art, other related drawings can also be obtained without creative labor on the basis of these drawings.

[0032] Figure 1 A flowchart of the method for regulating the scattering field of the reconfigurable metasurface provided in the embodiments of the application; Figure 2 A first specific flowchart of step S120 in the method for regulating the scattering field of the reconfigurable metasurface provided in the embodiments of the application; Figure 3 A second specific flowchart of step S120 in the method for regulating the scattering field of the reconfigurable metasurface provided in the embodiments of the application; Figure 4Unit structure schematic diagram of two reconfigurable metasurfaces provided for the embodiments of the present application; Figure 5 θ in = 0°, φ tar = 45° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by varactor diode; Figure 6 θ in = 20°, φ tar = 135° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by varactor diode; Figure 7 θ in = -40°, φ tar = 225° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by varactor diode; Figure 8 θ in = 60°, φ tar = 270° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by varactor diode; Figure 9 θ in = 0°, φ tar = 45° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by PIN diode; Figure 10 θ in = 0°, φ tar = 135° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by PIN diode; Figure 11 θ in = -20°, φ tar = 30° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by PIN diode; Figure 12 θ in = -50°, φ tar = 270° reconfigurable metasurface capacitor distribution and scattering field distribution after regulation by PIN diode; Figure 13 Functional module diagram of the regulation device of the reconfigurable metasurface scattering field provided for the embodiments of the present application. DETAILED DESCRIPTION The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this application.

[0034] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0035] To facilitate understanding, we will first introduce reconfigurable metasurfaces.

[0036] Reconfigurable metasurfaces are an emerging type of artificial two-dimensional electromagnetic structure, composed of subwavelength-scale electromagnetic units arranged periodically or aperiodically on a two-dimensional plane. The core of this technology lies in integrating actively adjustable elements within the units, such as varactor diodes, PIN diodes, microelectromechanical switches, and graphene, and applying external excitation to achieve real-time, dynamic control of the unit's electromagnetic response.

[0037] Please refer to Figure 1 , Figure 1 This is a flowchart of a method for controlling a reconfigurable metasurface scattering field according to an embodiment of this application. The method for controlling a reconfigurable metasurface scattering field according to an embodiment of this application includes: Step S120: Based on the type of electromagnetic modulation element in the reconfigurable metasurface, select the load impedance vector to be optimized and input it into the model for scattering field calculation to obtain the real-time scattering field distribution.

[0038] The type of electromagnetic modulation element in the reconfigurable metasurface in step S120 includes analog modulation elements and digital modulation elements. For example, a varactor diode is an analog modulation element, and its capacitance value can be adjusted by changing the bias voltage; a PIN diode is a digital modulation element, and its on-off state can be controlled by changing the bias voltage. The load impedance vector is a vector composed of the load impedance of each electromagnetic modulation element. The model of the scattering field calculation is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattering field. The model of the scattering field calculation can be used to describe the real-time scattering field distribution of the reconfigurable metasurface under given electromagnetic parameters, such as the direction and intensity of the electromagnetic wave scattered on the reconfigurable metasurface; the reflection coefficient for describing the intensity of the reflected wave in each direction; the transmission coefficient for describing the intensity of the transmitted wave in each direction, etc. The electromagnetic parameters can include the load impedance vector, the incident angle and frequency of the incident wave, the geometric parameters and material parameters of the unit in the reconfigurable metasurface, etc.

[0039] Step S140: Based on the difference between the real-time scattering field distribution and the target scattering field distribution, and combined with the type of electromagnetic modulation element, a corresponding convex optimization algorithm is used to obtain the optimized load impedance vector.

[0040] In step S140, the real-time scattering field distribution is obtained by inputting the load impedance vector to be optimized into the scattering field calculation model, and the target scattering field distribution is a pre-defined desired scattering field distribution. For example, it is desired to achieve high gain in a certain specific direction and low sidelobe level in other directions. By comparing the real-time scattering field distribution with the target scattering field distribution, the difference between the two is calculated. Common difference measurement calculation methods can include mean square error (MSE), sidelobe level (SLL), main lobe gain, etc.

[0041] In the process of calculating the optimized load impedance vector by using the difference and the convex optimization algorithm, the difference can be used to define an objective function, for example, the objective function can be to minimize the sidelobe level or maximize the main lobe gain. Some constraints are defined to ensure that the optimization result is physically feasible, for example, the capacitance value of the varactor diode must be between C min and C max , and the state of the PIN diode must be 0 or 1. After defining the objective function and the constraints, the convex optimization algorithm is used to calculate the optimized load impedance vector.

[0042] Step S160: Input the optimized load impedance vector into the scattering field calculation model for iteration to obtain the final load impedance vector. In step S160, the optimized load impedance vector calculated in step S140 is input into the model for calculating the scattering field again. After repeating step S140 for multiple times, i.e., after multiple iterations, a final load impedance vector is obtained. The final load impedance vector corresponds to the modulation state of each electromagnetic modulation element in the reconfigurable metasurface, e.g., the capacitance value of a varactor diode or the on / off state of a PIN diode. Moreover, the final load impedance vector means that after being input into the model for calculating the scattering field, the real-time scattering field distribution output by the model satisfies the expectation, i.e., the difference between the output real-time scattering field distribution and the target scattering field distribution is small enough.

[0043] Step S180: Based on the final load impedance vector, the lumped element parameters of the electromagnetic modulation elements are calculated.

[0044] In step S180, the lumped element parameters of the electromagnetic modulation elements refer to equivalent parameters related to the electromagnetic modulation elements, which are used to describe the electromagnetic characteristics of the electromagnetic modulation elements under specific working conditions.

[0045] In the implementation process, by establishing a model for calculating the scattering field and performing iterative calculation based on the convex optimization algorithm, the final load impedance vector is obtained, and based on the final load impedance vector, the lumped element parameters of the electromagnetic modulation elements are calculated. In this way, high-precision control of the scattering field of the reconfigurable metasurface is ensured, and the optimization efficiency is improved and the data dependence is greatly reduced. Therefore, high optimization precision and low computational overhead are achieved.

[0046] In some optional embodiments, the model for calculating the scattering field is a scattering field forward calculation model, and the specific formula of the model is as follows:

[0047] where θ and φ represent the pitch angle and the azimuth angle of the scattering field, respectively. represents the diagonal matrix of the vector. is an M-dimensional vector, representing the scattering field distribution of the reconfigurable metasurface, and M represents the sampling number of the scattering field. represents the load impedance of the electromagnetic modulation element, and is an N-dimensional vector. is an M-dimensional vector, representing the scattering field of the reconfigurable metasurface when the load impedance tends to infinity. is an MxN matrix, N represents the number of reconfigurable units in the reconfigurable metasurface, and the (m, n)th element in the MxN matrix represents the radiation electric field intensity in the mth sampling direction when the nth reconfigurable unit is excited by a unit current. Z is an NxN matrix, and the element in the NxN matrix represents the mutual impedance and self-impedance of the reconfigurable unit. z represents the induced voltage on each electromagnetic modulation element of the reconfigurable metasurface when the load impedance tends to infinity, that is, the open circuit voltage.

[0048] In the above implementation process, by using the specific scattering field forward calculation model, compared with other models such as full-wave simulation model and equivalent circuit model, higher precision, lower data requirement and flexibility are obtained, and the model provides a general optimization framework for solving the optimization problem of continuous (analog modulation element) and discrete electromagnetic modulation element (digital modulation element), thereby realizing the unified processing of the reconfigurable metasurfaces corresponding to the two types of electromagnetic modulation elements. Therefore, the high-precision regulation and control of the scattering field of the reconfigurable metasurface is further improved, and the optimization efficiency is further improved.

[0049] Please refer to Figure 2 , Figure 2 The first specific flowchart of step S120 in the reconfigurable metasurface scattering field regulation and control method provided by the embodiments of the present application is provided. In some optional embodiments, the electromagnetic modulation element includes an analog modulation element.

[0050] Correspondingly, step S120 includes: Step S121: uniformly selecting N complex impedance values between the minimum and maximum capacitance values of the analog modulation element to form an N-dimensional load impedance vector to be optimized.

[0051] In the above step S121, N represents the number of reconfigurable units in the reconfigurable metasurface. The complex impedance value is usually represented in the form of Z=R+jX, R is the resistance (real part) and the unit is ohm (Ω). X is the reactance (imaginary part) and the unit is also ohm (Ω). j is the imaginary unit and satisfies j 2 =-1. Uniformly selecting means that the complex impedance values are uniformly distributed in the impedance transformation range of each analog modulation element, that is, each value has the same probability of being selected. The selection method of the complex impedance value in step S121 is equivalent to initializing the load impedance vector to be optimized.

[0052] Step S122: inputting the model of the scattering field calculation to obtain a real-time scattering field distribution.

[0053] In the implementation process, when the electromagnetic modulation element is specifically an analog modulation element, the N complex impedance values are uniformly selected from between the minimum capacitance value and the maximum capacitance value of the analog modulation element, thereby providing a reasonable initial value for iteration using the convex optimization algorithm, and thereby improving the efficiency and convergence speed of the iteration algorithm.

[0054] In some optional embodiments, step S140 includes: Step S141: calculating the optimized load impedance vector using the following formula:

[0055] The formula in step S141 is specifically for the case where the electromagnetic modulation element is specifically an analog modulation element. In this case, represents the optimized load impedance vector obtained in the kth iteration. min represents the minimum value, and max represents the maximum value. Re represents the real part of a complex number, and Im represents the imaginary part of a complex number, represents the modulus of a complex number, represents the Euclidean norm of a vector. θ and φ represent the elevation angle and the azimuth angle of the scattering field, respectively, and θ0 and φ0 represent the elevation angle and the azimuth angle of the main lobe direction of the scattering field. represents a set of side lobe regions. ω represents the operating angular frequency of the electromagnetic wave. and respectively represent the parasitic resistance value and the parasitic inductance value of the analog modulation element. and respectively represent the minimum capacitance value and the maximum capacitance value of the analog modulation element. represents the maximum difference between the corresponding elements of the optimized load impedance vector obtained in the kth iteration and the optimized load impedance vector obtained in the k-1th iteration. represents the gradient value.

[0056] In the formula, the part starting with represents the objective function, and in the embodiments of the present application, the part after represents the side lobe level, that is, the part of the formula represents the optimization target of minimizing the side lobe level.

[0057] In the formula, the part starting with s.t. represents the constraint condition. The constraint condition limits the value range of the variable, to ensure that the solution of the optimization problem is feasible in practical applications, that is, the obtained optimized load impedance vector is feasible in practical applications.

[0058] In the implementation process, in the case that the electromagnetic modulation element is specifically an analog modulation element, a specific convex optimization method is specifically provided for optimization with the goal of minimizing the sidelobe level. By introducing the optimization formula of the perturbation theory, the load impedance vector to be optimized is optimized, which can accurately describe the scattering characteristics of electromagnetic waves on the metasurface, thereby further improving the optimization accuracy. Moreover, the data required by the formula is less, thereby further reducing the computational overhead. That is, high optimization accuracy and low computational overhead are better balanced.

[0059] In some optional embodiments, step S180 comprises: Step S181: Calculate the lumped element parameter according to the following formula:

[0060] In step S181, C opt represents the lumped element parameter, that is, the capacitance value of each analog modulation element in the case that the electromagnetic modulation element is specifically an analog modulation element. Im represents the imaginary part, and the physical meanings of the remaining parameters are the same as those of the corresponding parameters in the previous formula. In the formula, since the load impedance z L is a complex number, the real part of the complex number is the resistance part, and the imaginary part is the reactance part, so the reactance part in the load impedance z L can be extracted by the imaginary part algorithm Im, and the influence of the parasitic inductance is excluded by subtracting the additional inductance part corresponding to the parasitic inductance from the total reactance, to calculate the final lumped element parameter.

[0061] In the implementation process, in the case that the electromagnetic modulation element is specifically an analog modulation element, the influence of the parasitic inductance on the calculation result is excluded by the calculation formula of the lumped element parameter, so that the calculated lumped element parameter, that is, the capacitance value of each analog modulation element, is more accurate.

[0062] Please refer to Figure 3 , Figure 3 is the second specific flowchart of step S120 in the method for regulating and controlling the scattering field of the reconfigurable metasurface provided by the embodiments of the present application. In some optional embodiments, the electromagnetic modulation element comprises a digital modulation element.

[0063] Correspondingly, step S120 comprises: Step S123: Generate N 0s or 1s with equal probability and independence to form an N-dimensional load impedance vector to be optimized.

[0064] In step S123, N represents the number of reconfigurable units in the reconfigurable metasurface. Since the digital modulation element usually has only two states, on and off, 0 and 1 can be used to represent them respectively. Equal-probability and independent generation means that each digital modulation element takes 1 or 0 with equal probability, and the digital modulation elements are independent of each other. Step S123 is equivalent to initializing the load impedance vector to be optimized.

[0065] Step S124: input the model of the scattering field calculation to obtain the real-time scattering field distribution.

[0066] In the above implementation process, when the electromagnetic modulation element is a digital modulation element, the load impedance vector to be optimized is constructed by generating N 1s or 0s with equal probability and independence. This also provides a reasonable initial value for iteration using the convex optimization algorithm, thereby improving the efficiency and convergence speed of the iteration algorithm.

[0067] In some optional embodiments, step S140 includes: Step S142: calculate the optimized load impedance vector using the following formula:

[0068] In step S142, c （k） represents the optimized load impedance vector obtained in the kth iteration. min represents the minimum value, and max represents the maximum value. θ and φ represent the elevation angle and azimuth angle of the scattering field respectively, and θ0 and φ0 represent the elevation angle and azimuth angle of the main lobe direction of the scattering field. represents a set of side lobe regions. λ is a regularization parameter. represents the load impedance, and the relationship between the configuration vector c and the load impedance satisfies the following formula:

[0069] wherein c = c （1）… c （k-1）、 c （k） , and and represent the parasitic resistance value, the parasitic inductance value and the capacitance value when off of the digital modulation element respectively. represents the gradient value.

[0070] In the above formula, the part starting with represents the objective function, and in the embodiments of the present application, the part after represents the side lobe level, that is, the part of the above formula represents the optimization target of minimizing the side lobe level.

[0071] In the above formula, the part starting with s.t. represents a constraint condition. The value range of the variable is limited through the constraint condition to ensure that the solution of the optimization problem is feasible in practical application, that is, the optimized load impedance vector obtained is feasible in practical application.

[0072] In the above implementation process, in the case where the electromagnetic modulation element is specifically a digital modulation element, a specific convex optimization method is specifically provided for optimization with the goal of minimizing the sidelobe level. Through the introduced regularization term, the discrete binary combination optimization problem is ingeniously solved under the continuous convex optimization framework, and further, the data amount required by the formula is less, thereby further reducing the calculation overhead. That is, high optimization precision and low calculation overhead are better balanced.

[0073] As an optional implementation, in the case where the electromagnetic modulation element is specifically a digital modulation element, the on or off state of the digital modulation element can be directly determined by configuring a binary configuration impedance vector. For example, 0 represents the on state and 1 represents the off state.

[0074] In some optional implementations, step S160 includes: Step S161: inputting the optimized load impedance vector into a model of a scattering field calculation for iteration until the number of iterations reaches an iteration number threshold, to obtain a final load impedance vector.

[0075] In the above step S161, a person skilled in the art can determine according to the fineness requirement of the optimization result. The more the number of iterations, the more the fineness of the result.

[0076] In the above implementation process, due to the characteristics of the convex optimization algorithm, theoretically, interrupting the algorithm after any iteration can obtain a physically realizable impedance configuration, and the performance of the configuration is usually better than that of the result of the previous iteration. Therefore, by pre-allocating a calculation budget for the optimization process and outputting the optimization result when the budget is exhausted, the entire iteration process is changed into a “calculation process” with predictable performance, controllable time consumption and reliable result, so that the regulation of the reconfigurable metasurface scattering field is more stable and efficient.

[0077] The specific parameters combined by the embodiments of the present application are used to verify the regulation method of the reconfigurable metasurface scattering field provided by the embodiments of the present application.

[0078] Please refer to Figure 4 , Figure 4 FIGS. 1 and 2 are schematic diagrams of unit structures of two reconfigurable metasurfaces provided by the embodiments of the present application. FIG. 1 is a schematic diagram of a 10x10 unit reconfigurable metasurface regulated by a varactor diode, and FIG. 2 is a schematic diagram of a 12x12 unit reconfigurable metasurface regulated by a PIN diode. Figure 4The unit parameters in the middle (a) are: p=18mm, length l1=16mm, l2=8.93mm, w1=8.07mm, w2=2.26mm, w3=0.5mm, FR-4 dielectric substrate is used, and the thickness h=2mm; Figure 4 The unit parameters in the middle (b) are: p=16mm, l1=13.5mm, l2=5mm, w1=1mm, w2=5.75mm, w3=0.5mm, F4B-350 dielectric substrate is used, and the thickness h=3mm. Among them, the PIN diode controls the on and off state through the direct current bias circuit, and the varactor diode adjusts the capacitance value through the variable bias voltage. The varactor diode parameters are R var =2Ω, L var =0.4nH, C min =0.15pF, C max =1.15pF (model M / A-COM MA46H120); the PIN diode parameters are R PIN =2Ω, L PIN =0.45nH, C PIN =0.15pF (model SMP1345-040LF).

[0079] For the parameter setting in the algorithm, K=20, δ0=200, β=0.8, λ=100 are considered. Among them, K is the maximum number of iterations, δ0is the initial step length of the load impedance change in iteration, β is the attenuation coefficient, and λ is the regularization parameter.

[0080] First, consider the scattering field control of the 10*10 unit reconfigurable metasurface controlled by the varactor diode, respectively in the incident wave direction θ in =0°, 20°, -40°, 60°, the target makes the main beam deflection angle (θ tar , φ tar )=(30°, 45°), (45°, 135°), (50°, 225°), (60°, 270°).

[0081] Please refer to Figures 5 to 8 , Figure 5 is a schematic diagram of the reconfigurable metasurface capacitance distribution and the scattering field distribution after control by the varactor diode when θ in =0°, φ tar =45°; Figure 6 is a schematic diagram of the reconfigurable metasurface capacitance distribution and the scattering field distribution after control by the varactor diode when θ in =20°, φ tar =135°; Figure 7 is a schematic diagram of the reconfigurable metasurface capacitance distribution and the scattering field distribution after control by the varactor diode when θ in=-40°、φ tar A schematic diagram of the reconfigurable metasurface capacitance distribution controlled by a varactor diode at 225° and the scattering field distribution after control. Figure 8 The θ provided in the embodiments of this application in =60°, φ tar A schematic diagram showing the reconfigurable metasurface capacitance distribution controlled by a varactor diode at 270° and the resulting scattering field distribution. From... Figures 5 to 8 As can be seen, for the reconfigurable metasurface controlled by varactor diodes, under different incident wave angles and different target beam directions, the reconfigurable metasurface scattering field control method provided in this application has optimized the corresponding capacitance distribution, achieved precise beam pointing and low sidelobe effect, thus proving the effectiveness of the reconfigurable metasurface scattering field control method provided in this application for controlling the scattering field of the reconfigurable metasurface controlled by varactor diodes.

[0082] Furthermore, considering the scattering field modulation of a 12×12 unit reconfigurable metasurface controlled by PIN diodes, respectively, at incident wave direction θ in Given 0°, 0°, 20°, and -50°, the target causes the main beam deflection angle to be (θ). tar , φ tar =(30°, 45°),(60°, 135°),(20°, 30°),(50°, 270°).

[0083] Please refer to Figures 9 to 12 , Figure 9 θ is provided for the embodiments of this application. in =0°、φ tar A schematic diagram of the reconfigurable metasurface capacitance distribution controlled by a PIN diode at 45° and the scattering field distribution after control. Figure 10 The θ provided in the embodiments of this application in =0°、φ tar A schematic diagram of the reconfigurable metasurface capacitance distribution controlled by a PIN diode at 135° and the scattering field distribution after control. Figure 11 The θ provided in the embodiments of this application in =-20°、φ tar A schematic diagram of the reconfigurable metasurface capacitance distribution controlled by a PIN diode and the scattering field distribution after control at 30°. Figure 12 The θ provided in the embodiments of this application in =-50 °、φ tar A schematic diagram showing the reconfigurable metasurface capacitance distribution controlled by a PIN diode at 270° and the resulting scattering field distribution. From... Figures 9 to 12It can be seen that, for the reconfigurable metasurface regulated by the PIN diode, the reconfigurable metasurface scattering field regulation method provided in the application optimizes the corresponding capacitance distribution under the incidence of incident waves at different angles and different target beam directions, realizes accurate beam pointing and low sidelobe effect, and thus proves the effectiveness of the reconfigurable metasurface scattering field regulation method provided in the application on the scattering field regulation of the reconfigurable metasurface controlled by the variable capacitance diode. When the normal incidence occurs, the conventional phase gradient regulation method produces conjugate symmetric double beams, while the application realizes the generation and direction regulation of single beams through accurate forward modeling and reverse optimization strategies, and thus exhibits the superiority of the reconfigurable metasurface scattering field regulation method provided in the embodiments of the application over the conventional regulation method.

[0084] Please refer to Figure 13 , Figure 13 is a functional module diagram of the reconfigurable metasurface scattering field regulation device provided in the embodiments of the application. Based on the same concept, the embodiments of the application provide a reconfigurable metasurface scattering field regulation device 100, which comprises: The selection module 110 is configured to select a load impedance vector to be optimized according to the type of the electromagnetic modulation element in the reconfigurable metasurface, and input the load impedance vector to a model of scattering field calculation to obtain a real-time scattering field distribution; wherein the model of scattering field calculation is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattering field. The iteration module 120 is configured to obtain an optimized load impedance vector by using a corresponding convex optimization algorithm based on the difference between the real-time scattering field distribution and a target scattering field distribution, and in combination with the type of the electromagnetic modulation element. The iteration module 120 is further configured to input the optimized load impedance vector into the model of scattering field calculation for iteration to obtain a final load impedance vector. The calculation module 130 is configured to calculate the lumped element parameters of the electromagnetic modulation element based on the final load impedance vector.

[0085] As an optional implementation, the model of scattering field calculation is as follows:

[0086] wherein θ and φ respectively represent the elevation angle and the azimuth angle of the scattering field; represents the diagonal matrix of the vector; is an M-dimensional vector, and represents the scattering field distribution of the reconfigurable metasurface; represents the load impedance of the electromagnetic modulation element; is an M-dimensional vector, and represents the scattering field of the reconfigurable metasurface when the load impedance tends to infinity, and M represents the sampling number of the scattering field; is an MxN matrix, N represents the number of reconfigurable units in the reconfigurable metasurface, the (m, n)th element in the MxN matrix represents the radiation electric field intensity in the mth sampling direction when the nth reconfigurable unit is excited by a unit current; Z is an NxN matrix, the element in the NxN matrix represents mutual impedance and self-impedance of the reconfigurable unit; v represents the induced voltage on each electromagnetic modulation element of the reconfigurable metasurface when the load impedance tends to infinity.

[0087] As an optional implementation, the electromagnetic modulation element includes an analog modulation element. In the process of selecting the load impedance vector to be optimized according to the type of the electromagnetic modulation element in the reconfigurable metasurface, and inputting the model of the scattering field calculation to obtain the real-time scattering field distribution, the selecting module 110 is specifically configured to: uniformly select N complex impedance values between the minimum capacitance value and the maximum capacitance value of the analog modulation element to form an N-dimensional load impedance vector to be optimized; wherein N represents the number of reconfigurable units in the reconfigurable metasurface; and input the model of the scattering field calculation to obtain the real-time scattering field distribution.

[0088] As an optional implementation, in the process of obtaining the optimized load impedance vector based on the difference between the real-time scattering field distribution and the target scattering field distribution, and combining the type of the electromagnetic modulation element to adopt a corresponding convex optimization algorithm, the iteration module 120 is specifically configured to: calculate the optimized load impedance vector by using the following formula:

[0089] wherein, represents the optimized load impedance vector obtained in the kth iteration; min represents the minimum value, and max represents the maximum value; Re represents the real part of a complex number, and Im represents the imaginary part of a complex number, represents the modulus of a complex number, represents the Euclidean norm of a vector; θ and φ respectively represent the pitch angle and the azimuth angle of the scattering field, and θ0 and φ0 represent the pitch angle and the azimuth angle of the main lobe direction of the scattering field; represents a set of side lobe regions; ω represents the operating angular frequency of the electromagnetic wave; and respectively represent the parasitic resistance value and the parasitic inductance value of the analog modulation element; and respectively represent the minimum capacitance value and the maximum capacitance value of the analog modulation element; represents the maximum difference between the corresponding elements of the optimized load impedance vector obtained in the kth iteration and the optimized load impedance vector obtained in the k-1th iteration; represents the gradient value.

[0090] As an optional implementation, in the process of calculating the lumped element parameters of the electromagnetic modulation element based on the final load impedance vector, the calculation module 130 is specifically configured to calculate the lumped element parameters according to the following formula:

[0091] In the formula, C opt represents the lumped element parameters.

[0092] As an optional implementation, the electromagnetic modulation element includes a digital modulation element. In the process of selecting the load impedance vector to be optimized according to the type of the electromagnetic modulation element in the reconfigurable metasurface, inputting the model of the scattering field calculation, and obtaining the real-time scattering field distribution, the selection module 110 is specifically configured to: generate N 0s or 1s with equal probability and independence to form an N-dimensional load impedance vector to be optimized; wherein N represents the number of reconfigurable units in the reconfigurable metasurface; input the model of the scattering field calculation to obtain the real-time scattering field distribution.

[0093] As an optional implementation, in the process of obtaining the optimized load impedance vector based on the difference between the real-time scattering field distribution and the target scattering field distribution, and combining the type of the electromagnetic modulation element with the corresponding convex optimization algorithm, the iteration module 120 is specifically configured to calculate the optimized load impedance vector using the following formula:

[0094] In the formula, c （k） represents the optimized load impedance vector obtained in the kth iteration; min represents the minimum value, and max represents the maximum value; θ and φ represent the elevation angle and azimuth angle of the scattering field, respectively, and θ0 and φ0 represent the elevation angle and azimuth angle of the main lobe direction of the scattering field; represents a set of side lobe regions; λ is a regularization parameter; represents the load impedance, and the relationship between the load impedance and the configuration vector c satisfies the following formula:

[0095] wherein c= c （1）… c （k-1）、 c （k） , and and respectively represent the parasitic resistance value, the parasitic inductance value and the capacitance value when the digital modulation element is disconnected. represents a gradient value.

[0096] As an optional implementation, in the process of inputting the optimized load impedance vector into the model of the scattering field calculation to obtain the final load impedance vector, the iteration module 120 is specifically configured to: input the optimized load impedance vector into the model of the scattering field calculation until the number of iterations reaches the iteration number threshold to obtain the final load impedance vector.

[0097] It should be understood that the device corresponds to the above-mentioned reconfigurable metasurface scattering field regulation method embodiments, and can perform each step involved in the above-mentioned method embodiments. The specific functions of the device can be referred to the description in the above, and the detailed description is appropriately omitted here to avoid repetition. The device includes at least one software function module that can be stored in the memory in the form of software or firmware or solidified in the operating system (OS) of the device.

[0098] Based on the same idea, the embodiments of the present application provide a computer program product. The computer program product includes computer programs or instructions. When the computer programs or instructions are executed by a processor, the method described in any embodiment of the present application can be implemented.

[0099] The computer program product can be embodied on one or more computer readable media. The computer readable media can be, but are not limited to, volatile memory (such as random access memory RAM), non-volatile memory (such as read only memory ROM, programmable read only memory PROM, erasable programmable read only memory EPROM, electrically erasable programmable read only memory EEPROM, flash memory), magnetic storage devices (such as hard drives, magnetic tapes), optical storage devices (such as compact discs CD-ROM, digital versatile discs DVD), or any suitable combination of the above.

[0100] Specifically, the computer programs or instructions can be stored in the computer readable medium. When the computer readable medium containing the computer programs or instructions is loaded into an electronic device with processing capability, the processor of the electronic device can read and execute the computer programs or instructions. The execution of the instructions by the processor makes the electronic device perform the method steps described in the embodiments of the present application.

[0101] Those skilled in the art can understand that the computer program product can exist in various forms, including but not limited to: Standalone software: a software package stored on a physical medium (such as a CD, a USB flash disk, a memory card) and sold or distributed independently.

[0102] Pre-installed software: a part of firmware or system / application software that has been pre-burned or installed in the device memory (such as ROM, Flash) when the device is shipped.

[0103] Network distribution: Software installation packages, update packages, or applications downloaded or streamed from servers, app stores (such as Apple App Store, Google Play), software repositories, etc. via the Internet, mobile networks, etc.

[0104] Embedded software: As part of the control system of specialized equipment (such as medical imaging equipment, industrial testing equipment), it is stored in the internal memory of the device.

[0105] Cloud Service / SaaS: Deployed in a cloud computing environment, users remotely access and invoke the program's functions through client software, web browsers, or application programming interfaces (APIs) (i.e., the "Software as a Service" model). In this case, the program's execution occurs on a cloud server, but the instructions themselves and the core logic for implementing their functions still fall under the category of the computer program product.

[0106] License key / activation code: A digital key separate from the main program but used to unlock or activate the program to enable the functions of the method, and is considered part of or an accessory to the product.

[0107] Regardless of the specific form in which the computer program product is provided or distributed, as long as the computer program or instructions contained therein can implement the methods described in the embodiments of this application when executed by a processor, they fall within the protection scope of the computer program product described in this embodiment.

[0108] The computer program product in this embodiment can be used to cause an electronic device with processing capabilities to perform the steps in the various methods provided in the embodiments of this application.

[0109] It should be understood that the disclosed apparatus and methods can also be implemented in other ways, given the several embodiments provided in this application. The apparatus embodiments described above are merely illustrative. For example, the flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of apparatus, methods, and computer program products according to various embodiments of this application. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of code, which contains one or more executable instructions for implementing a specified logical function. It should also be noted that in some alternative implementations, the functions marked in the blocks may occur in a different order than those marked in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, or they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in a block diagram and / or flowchart, and combinations of blocks in block diagrams and / or flowcharts, can be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0110] In addition, the functional modules in the various embodiments of this application can be integrated together to form an independent part, or each module can exist independently, or two or more modules can be integrated to form an independent part.

[0111] The above description is only an optional implementation of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application.

Claims

1. A method for controlling the scattering field of a reconfigurable metasurface, characterized in that, include: Based on the type of electromagnetic modulation element in the reconfigurable metasurface, the load impedance vector to be optimized is selected and input into the model for calculating the scattered field to obtain the real-time scattered field distribution; wherein, the model for calculating the scattered field is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattered field; Based on the difference between the real-time scattered field distribution and the target scattered field distribution, and combined with the type of the electromagnetic modulation element, a corresponding convex optimization algorithm is adopted to obtain the optimized load impedance vector; The optimized load impedance vector is input into the model for calculating the scattered field and iterated to obtain the final load impedance vector; and Based on the final load impedance vector, the lumped element parameters of the electromagnetic modulation element are calculated.

2. The method according to claim 1, characterized in that, in, The model for calculating the scattering field is as follows: Where θ and φ represent the pitch angle and azimuth angle of the scattered field, respectively; Represents the diagonal matrix representation of a vector; Let be an M-dimensional vector representing the scattering field distribution of the reconfigurable metasurface; This represents the load impedance of the electromagnetic modulation element; Let M be an M-dimensional vector representing the scattering field of the reconfigurable metasurface as the load impedance approaches infinity, where M represents the number of samples of the scattering field. Z is an M×N dimensional matrix, where N represents the number of reconfigurable units in the reconfigurable metasurface. The (m, n)th element in the M×N dimensional matrix represents the radiated electric field intensity in the m-th sampling direction when the n-th reconfigurable unit is excited by a unit current. Z is an N×N dimensional matrix, where the elements represent the mutual impedance and self-impedance of the reconfigurable units. v represents the induced voltage on each electromagnetic modulation element of the reconfigurable metasurface when the load impedance tends to infinity.

3. The method according to claim 1, characterized in that, in, The electromagnetic modulation element includes an analog modulation element; The step of selecting the load impedance vector to be optimized based on the type of electromagnetic modulation element in the reconfigurable metasurface and inputting it into the model for calculating the scattered field to obtain the real-time scattered field distribution includes: Between the minimum and maximum capacitance values ​​of the analog modulation element, N complex impedance values ​​are uniformly selected to form an N-dimensional load impedance vector to be optimized; where N represents the number of reconfigurable units in the reconfigurable metasurface. The real-time scattered field distribution is obtained by inputting the model for calculating the scattered field.

4. The method according to claim 3, characterized in that, Based on the difference between the real-time scattered field distribution and the target scattered field distribution, and combined with the type of the electromagnetic modulation element, a corresponding convex optimization algorithm is used to obtain the optimized load impedance vector, including: The optimized load impedance vector is calculated using the following formula: in, Let represent the optimized load impedance vector obtained in the k-th iteration; min indicates finding the minimum value, and max indicates finding the maximum value; Re represents the real part of the complex number, and Im represents the imaginary part of the complex number. Represents the modulus of a complex number. θ represents the Euclidean norm of the vector; θ and φ represent the pitch and azimuth angles of the scattered field, respectively; θ0 and φ0 represent the pitch and azimuth angles of the main lobe direction of the scattered field. ω represents the set of sidelobe regions; ω represents the operating angular frequency of the electromagnetic wave. and These represent the parasitic resistance and parasitic inductance values ​​of the analog modulation element, respectively. and These represent the minimum and maximum capacitance values ​​of the analog modulation element, respectively. This represents the maximum difference between corresponding elements in the optimized load impedance vector obtained in the k-th iteration and the optimized load impedance vector obtained in the (k-1)-th iteration; This represents the gradient value.

5. The method according to claim 4, characterized in that, The calculation of the lumped element parameters of the electromagnetic modulation element based on the final load impedance vector includes: The parameters of the lumped element are calculated according to the following formula: In the formula, C opt This represents the parameters of the lumped element.

6. The method according to claim 1, characterized in that, in, The electromagnetic modulation element includes a digital modulation element; The step of selecting the load impedance vector to be optimized based on the type of electromagnetic modulation element in the reconfigurable metasurface and inputting it into the model for calculating the scattered field to obtain the real-time scattered field distribution includes: N 0s or 1s are generated with equal probability and independently to form an N-dimensional load impedance vector to be optimized; where N represents the number of reconfigurable units in the reconfigurable metasurface. The real-time scattered field distribution is obtained by inputting the model for calculating the scattered field.

7. The method according to claim 6, characterized in that, Based on the difference between the real-time scattered field distribution and the target scattered field distribution, and combined with the type of the electromagnetic modulation element, a corresponding convex optimization algorithm is used to obtain the optimized load impedance vector, including: The optimized load impedance vector is calculated using the following formula: In the formula, c （k） denoted as the optimized load impedance vector obtained in the k-th iteration; min indicates finding the minimum value, and max indicates finding the maximum value; θ and φ represent the pitch and azimuth angles of the scattered field, respectively, and θ0 and φ0 represent the pitch and azimuth angles of the main lobe direction of the scattered field; Represents the set of sidelobe regions; λ is the regularization parameter; The load impedance is expressed as follows, and its relationship with the configuration vector c satisfies the following equation: Where c = c （1）… c （k-1）、 c （k） , and and These represent the parasitic resistance, parasitic inductance, and capacitance when the digital modulation element is disconnected, respectively. This represents the gradient value.

8. The method according to any one of claims 1 to 7, characterized in that, The step of iterating through the model for calculating the scattered field by inputting the optimized load impedance vector into the model to obtain the final load impedance vector includes: The optimized load impedance vector is input into the model for calculating the scattering field and iterated until the number of iterations reaches the iteration threshold to obtain the final load impedance vector.

9. A device for controlling the reconfigurable metasurface scattering field, characterized in that, include: A selection module is used to select the load impedance vector to be optimized according to the type of electromagnetic modulation element in the reconfigurable metasurface, and input it into the model for calculating the scattered field to obtain the real-time scattered field distribution; wherein, the model for calculating the scattered field is established based on the relationship between the load impedance of the electromagnetic modulation element and the scattered field; The iterative module is used to obtain the optimized load impedance vector by adopting the corresponding convex optimization algorithm based on the difference between the real-time scattered field distribution and the target scattered field distribution, combined with the type of the electromagnetic modulation element; The iteration module is also used to input the optimized load impedance vector into the model for calculating the scattered field and iterate to obtain the final load impedance vector. The calculation module is used to calculate the lumped element parameters of the electromagnetic modulation element based on the final load impedance vector.

10. A computer program product, characterized in that, Includes a computer program / instruction that, when executed by a processor, implements the method as described in any one of claims 1 to 8.

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