A method for predicting the radiation field of a flexible antenna after deformation

Abstract

The application discloses a flexible antenna deformation radiation field prediction method, comprising the following steps: initializing target parameters of a flexible antenna; obtaining a first change amount and a second change amount of each current vector of the flexible antenna after deformation based on the target parameters, wherein the first change amount is a change amount of an initial spatial position of the current vector, and the second change amount is a change amount of an initial spatial posture of the current vector; obtaining a current mode of the flexible antenna after deformation based on the first change amount and the second change amount of each current vector; and obtaining a prediction result of the radiation field of the flexible antenna after deformation based on the current mode of the flexible antenna after deformation, an impedance operator matrix and the target parameters of the flexible antenna. The application can adapt to different dimension deformations of the flexible antenna and ensure the prediction accuracy of the radiation field of the flexible antenna after deformation.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of flexible antennas, and particularly relates to a method for predicting the radiation field of a flexible antenna after deformation. BACKGROUND

[0002] A flexible antenna refers to an antenna made of flexible materials, which can maintain its electrical properties as much as possible under deformation conditions such as bending and folding. Flexible antennas are widely used in unmanned aerial vehicles, flexible electronic devices, wearable technology and other scenarios. The radiation field of a flexible antenna in the initial state is the ideal state of its design, and the radiation characteristics are optimal. However, with different use requirements, the flexible antenna will inevitably deform, and the deformation will significantly affect the current distribution on the surface of the flexible antenna and the radiation field.

[0003] The deformation form of a flexible antenna is various, which varies depending on the actual use requirements. For example, in cooperation with the belly of an unmanned aerial vehicle, the antenna may undergo cylindrical deformation; in cooperation with the radome of an aircraft, the antenna may undergo spherical deformation; in cooperation with wearable devices that deform with the human body, irregular multi-dimensional deformation may occur due to the need to closely match the surface curve of the human body. Although there have been some studies attempting to predict the radiation field of a flexible antenna after deformation, these studies mostly focus on one-dimensional deformation models, such as cylindrical deformation, i.e., these studies cannot fully consider the impact of complex multi-dimensional deformation on the electrical properties of a flexible antenna. Therefore, for a flexible antenna, how to accurately predict the change in its electrical properties under different complex deformations becomes a key to ensuring its stable operation in various practical applications.

[0004] In order to improve the accuracy and efficiency of prediction, a patent application with publication number CN115374631A and the title of "Flexible antenna one-dimensional deformation electrical property fast prediction method" proposes a fast prediction method for simulating the radiation field of a flexible antenna after one-dimensional deformation by using FEKO software. This method divides the microstrip antenna model into triangular meshes in the simulation software, calculates the antenna surface current distribution using RWG basis functions, and deduces the radiation field after deformation based on this. This method improves the calculation efficiency and also solves the problem of long calculation time of traditional methods. However, this method is only suitable for one-dimensional bending deformation, i.e., this method can only predict the radiation field of a flexible antenna after single-dimensional deformation, which limits the practicality and application of the method.

[0005] To broaden the application scope of prediction, patent application CN11920365A, entitled "Prediction Method of Radiation Field After Deformation of Flexible Antenna Based on Infinitely Small Dipole," proposes a method for predicting the radiation field after deformation of a flexible antenna based on infinitely small dipoles. This method equates the flexible antenna to multiple infinitely small dipoles by placing an infinitely small dipole at the center of each finite element unit. The radiation field after deformation is calculated by calculating the dipole moment of each infinitely small dipole, as well as the dyadic Green's function matrix and attitude matrix of the flexible antenna after deformation. This method, while ensuring prediction accuracy and efficiency, can adapt to different dimensional deformations of the flexible antenna, avoiding the shortcomings of existing technologies that calculate the radiation field using surface currents from a one-dimensional bending deformation model, thus broadening the applicability of the prediction. However, since this method relies on finite element mesh modeling of the flexible antenna, when the flexible antenna deforms with arbitrary curved surfaces (such as human skin, the surface of complex industrial equipment, etc.), the shape of the flexible antenna may not be directly obtainable with a clear finite element mesh. This makes it difficult to construct an accurate infinitely small dipole model, thereby reducing the accuracy and applicability of the prediction. Summary of the Invention

[0006] To overcome the shortcomings of the existing technology, this invention provides a method for predicting the radiation field of a flexible antenna after deformation. The technical problem to be solved by this invention is achieved through the following technical solution:

[0007] This invention provides a method for predicting the radiation field after deformation of a flexible antenna, comprising:

[0008] Initialize the target parameters of the flexible antenna. The target parameters of the flexible antenna include... N Each initial current mode includes 1 initial current mode. A The current vector, the th current vector a The initial spatial positions of the current vectors are , No. a The initial spatial orientation of the current vectors is , No. a The initial start coordinates and initial end coordinates of the current vectors are respectively and The thicknesses of the flexible antenna at the initial starting point coordinates and the initial ending point coordinates are respectively and The curved surface where the flexible antenna deforms has The coordinates of the nth sampling point, the th OK Sampling points of the column The coordinates are The incident electric field in the dielectric region of the flexible antenna is The incident magnetic field in the dielectric region of the flexible antenna is , the incident electric field of the flexible antenna metal region is ; wherein, , , , ;

[0009] Based on the target parameters of the flexible antenna, the first change amount and the second change amount of each current vector of the deformed flexible antenna are obtained, the first change amount is the change amount of the initial spatial position of the current vector , and the second change amount is the change amount of the initial spatial attitude of the current vector ;

[0010] Based on the first change amount and the second change amount of each current vector, the current mode of the deformed flexible antenna is obtained;

[0011] Based on the current mode of the deformed flexible antenna, the impedance operator matrix, and the target parameters of the flexible antenna, the prediction result of the radiation field of the deformed flexible antenna is obtained.

[0012] In an embodiment of the present application, based on the target parameters of the flexible antenna, the first change amount and the second change amount of each current vector of the deformed flexible antenna are obtained, including:

[0013] Based on the coordinates of the sampling points on the curved surface where the flexible antenna generates deformation and the two-dimensional non-uniform rational B-spline basis function, the curved surface equation where the flexible antenna generates deformation is calculated;

[0014] Based on the curved surface equation, the initial starting point coordinates of each current vector, and the thickness of the flexible antenna at each initial starting point coordinate, the starting point coordinates of each current vector of the deformed flexible antenna are calculated;

[0015] Based on the curved surface equation, the initial end point coordinates of each current vector, and the thickness of the flexible antenna at each initial end point coordinate, the end point coordinates of each current vector of the deformed flexible antenna are calculated;

[0016] Based on the starting point coordinates of each current vector of the deformed flexible antenna and the initial starting point coordinates of the corresponding current vector, the end point coordinates of each current vector of the deformed flexible antenna and the initial end point coordinates of the corresponding current vector, the first change amount and the second change amount of each current vector of the deformed flexible antenna are calculated.

[0017] In an embodiment of the present application, the calculation formula for calculating the curved surface equation where the flexible antenna generates deformation is:

[0018]

[0019] wherein, a surface equation for generating deformation of the flexible antenna, a two-dimensional non-uniform rational B spline basis function, and a two-dimensional non-uniform rational B spline basis function in each dimension, a first row column of sampling points , a first , or a first , of initial start point coordinates

[0020] In one embodiment of the present application, the calculation formulae for calculating the start point coordinates of the current vector and the end point coordinates of the current vector are respectively:

[0021]

[0022]

[0023] wherein, is the start point coordinates of the current vector, is a surface equation for generating deformation of the flexible antenna, is a modulo operation, is the end point coordinates of the current vector.

[0024] In one embodiment of the present application, the calculation formulae for calculating the first change amount and the second change amount of the current vector are respectively:

[0025]

[0026]

[0027]

[0028] wherein, is the first change amount of the current vector, is a modulo operation, is the second change amount of the current vector, is the start point coordinates of the current vector, is the end point coordinates of the current vector.

[0029] In one embodiment of the present application, the calculation formula for calculating the current mode after deformation of the flexible antenna is:

[0030]

[0031]

[0032] wherein, is the current mode of the deformed flexible antenna, and are rotation matrices that rotate each current vector along the positive direction of the x-axis and the positive direction of the y-axis by and respectively, and are rotation matrices that rotate each current vector along the positive direction of the x-axis and the positive direction of the y-axis by and respectively, is the initial current mode of the flexible antenna, is the Dirichlet sampling function, is the spatial position of each current vector of the deformed flexible antenna.

[0033] In an embodiment of the present application, the predicted result of the radiation field of the deformed flexible antenna is obtained based on the current mode of the deformed flexible antenna, the impedance operator matrix and the target parameters of the flexible antenna, and includes:

[0034] a target impedance matrix is calculated based on the current mode of the deformed flexible antenna and the impedance operator matrix;

[0035] a target excitation matrix is calculated based on the current mode of the deformed flexible antenna, the incident electric field of the dielectric region of the flexible antenna, the incident magnetic field of the dielectric region of the flexible antenna and the incident electric field of the metal region of the flexible antenna;

[0036] a target weight coefficient is calculated based on the target impedance matrix and the target excitation matrix;

[0037] the radiation field of the deformed flexible antenna is calculated based on the target weight coefficient and the current mode of the deformed flexible antenna.

[0038] In an embodiment of the present application, the calculation formula of the target impedance matrix is:

[0039]

[0040] wherein, is the target impedance matrix ， ~ ~ is the impedance matrix of each two current modes of the deformed flexible antenna;

[0041]

[0042] wherein, is the impedance matrix of the first current mode and the second current mode after deformation of the flexible antenna, m n is the impedance matrix of the first current mode and the second current mode after deformation of the flexible antenna, ， is the first current mode after deformation of the flexible antenna, m is the first current mode after deformation of the flexible antenna, n is the first current mode after deformation of the flexible antenna, is an inner product operation;

[0043]

[0044] wherein, and are identity matrix and zero matrix respectively, is a matrix obtained by establishing an electric field integral equation and a magnetic field integral equation on the outer surface of the flexible antenna medium area, is a matrix obtained by establishing an electric field integral equation and a magnetic field integral equation on the inner surface of the flexible antenna medium area and an electric field integral equation on the inner surface of the flexible antenna metal area, is a conjugate transpose operation;

[0045]

[0046]

[0047]

[0048]

[0049] wherein, is an imaginary unit, is an angular velocity of an electromagnetic wave, and are dielectric constants in vacuum medium and air medium respectively, and are magnetic permeabilities in vacuum and in medium respectively, and are integral operators representing field source relationship in a uniform infinite space, is a Hamiltonian operator, is a wave number of an electromagnetic wave, is a two-dimensional Green's function, is a Cauchy principal value of integration.

[0050] In an embodiment of the present application, the calculation formula for calculating the target excitation matrix is: ​​​

[0051]

[0052] in, The target incentive matrix, ~ ~ This is the excitation matrix for each current mode after the flexible antenna deformation;

[0053]

[0054]

[0055] in, The first after the flexible antenna deformation m Excitation matrix for each current mode, The first after the flexible antenna deformation m One current mode, Let be the initial excitation matrix. This is an inner product operation. and These are the identity matrix and the zero matrix, respectively. The matrix is ​​obtained by establishing electric field integral equations and magnetic field integral equations on the outer surface of the flexible antenna dielectric region. This is for taking the conjugate transpose operation.

[0056] In one embodiment of the present invention, the formulas for calculating the target weighting coefficient and the radiation field after the flexible antenna deformation are as follows:

[0057]

[0058] in, For the target weight coefficient, ~ ~ These are the weighting coefficients for each current mode after the flexible antenna has deformed;

[0059]

[0060] in, The first after the flexible antenna deformation n Weighting coefficients for each current mode The first after the flexible antenna deformation m The current mode and the first n Impedance matrix for each current mode. To Find the reverse. The first after the flexible antenna deformation m Excitation matrix for each current mode;

[0061]

[0062] wherein, is the radiation field of the deformed flexible antenna, is the imaginary unit, is the angular velocity of the electromagnetic wave, is the permeability in vacuum medium, is the dyadic Green's function, is the target weight coefficient, is the current mode of the deformed flexible antenna

[0063] Another aspect of the present application provides a storage medium, wherein a computer program is stored in the storage medium, and the computer program is used to execute the steps of the method for predicting the radiation field of the deformed flexible antenna according to any one of the above embodiments.

[0064] Still another aspect of the present application provides an electronic device, comprising a memory and a processor, wherein the memory stores a computer program, and the processor realizes the steps of the method for predicting the radiation field of the deformed flexible antenna according to any one of the above embodiments when invoking the computer program in the memory.

[0065] Compared with the prior art, the present application has the following beneficial effects:

[0066] (1) The method for predicting the radiation field of the deformed flexible antenna provided by the present application equates the flexible antenna to a plurality of current modes, each of which is composed of a plurality of current vectors, calculates the change amount of the spatial position and the change amount of the spatial posture of each current vector of the deformed flexible antenna, so as to obtain the current mode of the deformed flexible antenna based on the change amount of the spatial position and the change amount of the spatial posture of each current vector, and obtain the prediction result of the radiation field of the deformed flexible antenna based on the current mode of the deformed flexible antenna. Since the present application reflects the influence of the deformation of the flexible antenna on the radiation field on the change of the spatial position and the spatial posture of each current vector of the current mode, which is independent of the structure of the antenna itself, it can adapt to the case of different dimensional deformations of the flexible antenna, and avoid the defects of the prior art of calculating the radiation field by the surface current of the one-dimensional bending deformation model.

[0067] (2) Since the present application uses a large number of current vectors of the initial state of the flexible antenna A ( ) to calculate the current mode of the deformed flexible antenna corresponding thereto, the prediction accuracy of the radiation field of the deformed flexible antenna can be ensured.

[0068] (3) The application can improve the prediction efficiency of the radiation field of the flexible antenna after deformation by calculating the change amount of the spatial position and the spatial posture of the current vector in different deformation states to calculate the current mode of the flexible antenna after deformation, and then obtaining the prediction result of the radiation field of the flexible antenna after deformation based on the current mode of the flexible antenna after deformation.

[0069] The application will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF DRAWINGS

[0070] Figure 1 is a structural schematic diagram of a flexible antenna provided by an embodiment of the application;

[0071] Figure 2 is a flowchart of a prediction method of a radiation field of a flexible antenna after deformation provided by an embodiment of the application;

[0072] Figure 3 is a schematic diagram of a flexible antenna distributed in a Cartesian coordinate system provided by an embodiment. DETAILED DESCRIPTION

[0073] In order to further illustrate the technical means and effects adopted by the application to achieve the predetermined purpose, the prediction method of the radiation field of the flexible antenna after deformation according to the application is described in detail below in combination with the accompanying drawings and specific embodiments.

[0074] The foregoing and other technical contents, features and effects of the application can be clearly presented in the specific embodiment description below in combination with the accompanying drawings. Through the description of the specific embodiments, the technical means and effects adopted by the application to achieve the predetermined purpose can be understood more deeply and specifically. However, the accompanying drawings are provided for reference and illustration only, and are not used to limit the technical solutions of the application.

[0075] It should be noted that in this document, relational terms such as first and second are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any such actual relationship or order between such entities or actions. Moreover, the terms "comprising", "including", or any other variant thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or apparatus that includes a list of elements does not necessarily include only those elements in the list, but can include other elements not expressly listed or included. Without more limitations, the element defined by the sentence "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus including the element.

[0076] The present application is directed to the prior art for the low accuracy and applicability of the radiation field prediction after the deformation of the flexible antenna, and proposes a prediction method for the radiation field after the deformation of the flexible antenna. In order to facilitate the understanding of the scheme provided by the present application, before introducing the prediction method for the radiation field after the deformation of the flexible antenna provided by the present application, the structure of the flexible antenna is first introduced. Please refer to Figure 1 , Figure 1 It is a structural schematic diagram of a flexible antenna provided by an embodiment of the present application.

[0077] As shown in Figure 1 , the flexible antenna 100 includes a flexible substrate 110 and an ideal electrical conductor 120 coated thereon.

[0078] Specifically, the size of the flexible substrate 110 is (long x width x height), and the ideal electrical conductor 120 in the shape of an hourglass is coated at the geometric center of the upper surface thereof.

[0079] Among them, the ideal electrical conductor 120 includes two isosceles trapezoidal metal sheets 1201 of the same size, and the two isosceles trapezoidal metal sheets 1201 are arranged oppositely with the upper bases coinciding. The size of the upper base of the isosceles trapezoidal metal sheet 1201 is , the size of the lower base of the isosceles trapezoidal metal sheet 1201 is , the size of the height of the two isosceles trapezoidal metal sheets 1201 is , and the thickness of the isosceles trapezoidal metal sheet 1201 is .

[0080] After introducing the structure of the flexible antenna, the prediction method for the radiation field after the deformation of the flexible antenna provided by the present application is introduced in detail below. Please refer to Figure 2 , Figure 2 It is a flowchart of the prediction method for the radiation field after the deformation of the flexible antenna provided by an embodiment of the present application. The method includes the following steps:

[0081] S1: initializing the target parameters of the flexible antenna.

[0082] Among them, the target parameters of the flexible antenna include N initial current modes, each initial current mode includes A current vectors, the initial spatial position of the a-th current vector is , 0 , the initial start point coordinate and the initial end point coordinate of the a-th current vector are and , the thicknesses of the flexible antenna at the initial start point coordinate and the initial end point coordinate are and , and there are coordinates of the sampling points in the m-th row row coordinates of the sampling points in the m-th column are , 0 < m < M, , 0 < n < N, , the incident electric field of the flexible antenna medium region is , the incident magnetic field of the flexible antenna medium region is , the incident electric field of the flexible antenna metal region is ; wherein, , , , .

[0083] It can be understood that the initial current mode is a set of orthogonal current distribution solutions of the flexible antenna in a passive case, which is determined by the intrinsic electromagnetic characteristics of the flexible antenna and can be solved by characteristic mode theory. Each initial current mode is composed of a set of current vectors. Since the initial current modes are orthogonal to each other, they are often used as the basis function of the antenna current, so that the current distribution under any excitation is constructed, and the antenna performance is analyzed and optimized, which has good interpretability and physical intuition.

[0084] It should be noted that the flexible antenna in the embodiment of the application is distributed in a Cartesian coordinate system. Specifically, as shown in FIG. 1, the upper surface of the flexible antenna coincides with the XY plane, and the origin of the Cartesian coordinate system is located at the geometric center of the upper surface of the flexible antenna. In addition, the definition of the initial spatial position of each current vector is the distance between the current vector and the origin of the Cartesian coordinate system, and the definition of the initial spatial pose of each current vector is the angle between the current vector and the X-axis and the Y-axis, respectively. For example, as shown in FIG. 1, the initial spatial position of the m-th current vector is the distance between the current vector and the origin, and the initial spatial pose of the m-th current vector is the angle between the current vector and the X-axis and the Y-axis, respectively. Figure 3 Figure 3

[0085] ​​​​​​​​​​​​​​​​​​​​S2: Based on the target parameters of the flexible antenna, obtain the first and second changes of each current vector after the flexible antenna deformation. The first change is the initial spatial position of the current vector. Change The second variable is the initial spatial attitude of the current vector. Change .

[0086] In this embodiment of the invention, S2 includes the following steps:

[0087] S2.1: Coordinates of sampling points on a deformed surface generated by a flexible antenna and two-dimensional non-uniform rational... B Spline basis functions are used to calculate the surface equations for deformation caused by a flexible antenna.

[0088] Specifically, the formula for calculating the surface equation that causes deformation in a flexible antenna is as follows:

[0089]

[0090] in, The equation for the surface that causes deformation in a flexible antenna. For two-dimensional non-uniform rational B spline basis functions and Two-dimensional non-uniform rational B The order of the spline basis function in each dimension. For the first OK Coordinates of the sampling points of the column , For the initial starting point coordinates , Or the initial and final coordinates , .

[0091] S2.2: Based on the surface equation, the initial starting coordinates of each current vector, and the thickness of the flexible antenna at each initial starting coordinate, calculate the starting coordinates of each current vector after the flexible antenna is deformed.

[0092] Specifically, the formula for calculating the starting coordinates of the current vector is as follows:

[0093]

[0094] in, The coordinates of the starting point of the current vector. The equation for the surface that causes deformation in a flexible antenna. This is a mold taking operation.

[0095] It should be noted that the above S2.1: Obtain the partial derivative of the variable s with respect to the coordinate point (x, y) of the initial start point of the current vector, and then substitute the obtained partial derivative into the initial start point coordinate (x, y) to obtain the partial derivative value of the variable s at the coordinate point (x, y) of the initial start point of the current vector. S2.2: Obtain the partial derivative of the variable t with respect to the coordinate point (x, y) of the initial end point of the current vector, and then substitute the obtained partial derivative into the initial end point coordinate (x, y) to obtain the partial derivative value of the variable t at the coordinate point (x, y) of the initial end point of the current vector.

[0096] S2.3: Based on the surface equation, the initial end point coordinate of each current vector, and the thickness of the flexible antenna at each initial end point coordinate, the end point coordinate of each current vector after deformation of the flexible antenna is calculated.

[0097] Specifically, the calculation formula for calculating the end point coordinate of the current vector is:

[0098]

[0099] wherein, is the end point coordinate of the current vector, is the surface equation of the flexible antenna after deformation, is a modulo operation.

[0100] S2.4: Based on the start point coordinate of each current vector after deformation of the flexible antenna and the initial start point coordinate of the corresponding current vector, and the end point coordinate of each current vector after deformation of the flexible antenna and the initial end point coordinate of the corresponding current vector, the first change amount and the second change amount of each current vector after deformation of the flexible antenna are calculated.

[0101] Specifically, the calculation formulas for calculating the first change amount and the second change amount of the current vector are as follows:

[0102]

[0103]

[0104] ​​​​​​​​​​​​​​

[0105] in, This is the first change in the current vector. For mold taking operation, This is the second change in the current vector. The coordinates of the starting point of the current vector. The coordinates of the endpoint of the current vector.

[0106] S3: Based on the first and second changes of each current vector, the current mode after the flexible antenna deformation is obtained.

[0107] Specifically, the formula for calculating the current mode after deformation of the flexible antenna is as follows:

[0108]

[0109]

[0110] in, This represents the current mode after the flexible antenna deforms. and Each current vector is directed along... positive direction of axis and Rotation in the positive direction of the axis and The rotation matrix, The positive axis is the length direction of the flexible antenna. The positive axis is perpendicular to the upper surface of the flexible antenna and points in the direction of radiation of the flexible antenna. This represents the initial current mode of the flexible antenna. For the Dirichlet sampling function, This represents the spatial location of each current vector after the flexible antenna has deformed.

[0111] S4: Based on the current mode, impedance operator matrix, and target parameters of the flexible antenna after deformation, the prediction results of the radiation field after the flexible antenna deformation are obtained.

[0112] It should be noted that the predicted radiation field after deformation of a flexible antenna can be understood as the spatial distribution characteristics of the electromagnetic radiation generated by the flexible antenna after deformation. The predicted radiation field is typically presented in the form of a spatial function or a numerical matrix.

[0113] In this embodiment of the invention, S4 includes the following steps:

[0114] S4.1: The target impedance matrix is ​​calculated based on the current mode and impedance operator matrix after the flexible antenna deformation.

[0115] Specifically, the formula for calculating the target impedance matrix is ​​as follows:

[0116]

[0117] wherein Z is a target impedance matrix, is an impedance matrix of each two current modes after deformation of the flexible antenna;

[0118]

[0119] wherein, is an impedance matrix of the mth current mode and the nth current mode after deformation of the flexible antenna, 0 < m < M, 0 < n < N, m n m N n N is the mth current mode after deformation of the flexible antenna, m is the nth current mode after deformation of the flexible antenna, is an impedance operator matrix, n is an inner product operation;

[0120] wherein,

[0121] and are identity matrix and zero matrix respectively, is a matrix obtained by establishing electric field integral equation and magnetic field integral equation on the outer surface of the flexible antenna medium region, is a matrix obtained by establishing electric field integral equation and magnetic field integral equation on the inner surface of the flexible antenna medium region and establishing electric field integral equation on the inner surface of the flexible antenna metal region, is a conjugate transpose operation;

[0122]

[0123]

[0124]

[0125]

[0126] wherein, is an imaginary unit, is an angular velocity of electromagnetic wave, and are dielectric constant in vacuum medium and air medium respectively, and ​​​​​​​​​​The magnetic permeability in vacuum and in medium, respectively, and is an integral operator representing the relationship of field sources in a homogeneous infinite space, is a Hamiltonian operator, is the wave number of electromagnetic wave, is a two-dimensional Green's function, is the Cauchy principal value of integration.

[0127] S4.2: Based on the current mode after deformation of the flexible antenna, the incident electric field of the flexible antenna medium area is , the incident magnetic field of the flexible antenna medium area is , the incident electric field of the flexible antenna metal area is , and the target excitation matrix is calculated.

[0128] Specifically, the calculation formula of the target excitation matrix is:

[0129]

[0130] wherein, is the target excitation matrix, ~ ~ is the excitation matrix of each current mode after deformation of the flexible antenna;

[0131]

[0132]

[0133] wherein, is the excitation matrix of the m-th current mode after deformation of the flexible antenna, m is the m-th current mode after deformation of the flexible antenna, is the initial excitation matrix, m is the inner product operation, and are the unit matrix and the zero matrix, respectively, is a matrix obtained by establishing electric field integral equation and magnetic field integral equation on the outer surface of the flexible antenna medium area, is a conjugate transpose operation. S4.3: Based on the target impedance matrix and the target excitation matrix, the target weight coefficient is calculated.

[0134] Specifically, the calculation formula of the target weight coefficient is:

[0135]

[0136]

[0137] ​​wherein, is the target weight coefficient, ~ ~ is the weight coefficient of each current mode after deformation of the flexible antenna;

[0138]

[0139] wherein, is the weight coefficient of the n th current mode after deformation of the flexible antenna, is the impedance matrix of the m th current mode and the n th current mode after deformation of the flexible antenna, is the inverse of , is the excitation matrix of the m th current mode after deformation of the flexible antenna.

[0140] S4.4: based on the target weight coefficient and the current mode after deformation of the flexible antenna, the radiation field after deformation of the flexible antenna is calculated.

[0141] Specifically, the calculation formula for calculating the radiation field after deformation of the flexible antenna is:

[0142]

[0143] wherein, is the radiation field after deformation of the flexible antenna, is the imaginary unit, is the angular velocity of the electromagnetic wave, is the magnetic permeability in vacuum medium, is the dyadic Green's function, is the target weight coefficient, is the current mode after deformation of the flexible antenna.

[0144] In summary, the method for predicting the radiation field of the deformed flexible antenna provided by the embodiment of the present application, which equivalently regards the flexible antenna as a plurality of current modes, each of which is composed of a plurality of current vectors, calculates the change amount of the spatial position and the change amount of the spatial posture of each current vector of the deformed flexible antenna, so as to obtain the current mode of the deformed flexible antenna based on the change amount of the spatial position and the change amount of the spatial posture of each current vector, and obtain the prediction result of the radiation field of the deformed flexible antenna based on the current mode of the deformed flexible antenna. Since the present application reflects the influence of the deformation of the flexible antenna on the radiation field on the change of the spatial position and the spatial posture of each current vector of the current mode, which is irrelevant to the structure of the antenna itself, it can adapt to the case of different dimensional deformations of the flexible antenna, and avoid the defects of the prior art of calculating the radiation field by the surface current of the one-dimensional bending deformation model.

[0145] In addition, since the embodiment of the present application calculates the current mode of the deformed flexible antenna corresponding to the initial state of the flexible antenna using a large number of current vectors A of the flexible antenna, the prediction accuracy of the radiation field of the deformed flexible antenna can be ensured.

[0146] In addition, when analyzing different deformation states of a flexible antenna, since the current mode of the deformed flexible antenna is calculated by a plurality of current vectors of the initial state of the flexible antenna, when the antenna is deformed in different ways, only the change amount of the spatial position and the spatial posture of the current vector in the different deformation states needs to be calculated to calculate the current mode of the deformed flexible antenna, and then the prediction result of the radiation field of the deformed flexible antenna is obtained based on the current mode of the deformed flexible antenna, so that the prediction efficiency of the radiation field of the deformed flexible antenna can be improved by this method.

[0147] It should be noted that in actual application, after obtaining the radiation field of the deformed flexible antenna based on the above method, the structure (such as material, shape) of the flexible antenna can be adjusted based on the radiation field of the deformed flexible antenna to reduce the electromagnetic interference or signal attenuation caused by deformation, so as to ensure that the deformed flexible antenna still meets the communication requirements (such as gain, directivity) and ensures the stability of the communication link.

[0148] In the several embodiments of the present application, it should be understood that the disclosed device or method can be implemented in other ways. For example, the device embodiments described above are only illustrative, and the division of the modules is only a logical function division. In actual implementation, another division mode can be used, for example, a plurality of modules or components can be combined or integrated into another system, or some features can be ignored or not executed.

[0149] ​In addition, each functional module in each embodiment of the present application can be integrated in one processing module, or each module can exist physically independently, or two or more modules can be integrated in one module. The integrated module can be realized in the form of hardware or in the form of hardware plus software functional module.

[0150] Still another embodiment of the present application provides a storage medium in which a computer program is stored, the computer program being used to execute the steps of the method for predicting the radiation field of a flexible antenna after deformation according to the above embodiments.

[0151] Still another aspect of the present application provides an electronic device comprising a memory and a processor, the memory storing a computer program, and the processor invoking the computer program in the memory to implement the steps of the method for predicting the radiation field of a flexible antenna after deformation according to the above embodiments. Specifically, the integrated module realized in the form of software functional module can be stored in a computer readable storage medium. The software functional module stored in a storage medium comprises a plurality of instructions for causing an electronic device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute part of the steps of the method according to the embodiments of the present application. The aforementioned storage medium includes a U disk, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and various program code storage media.

[0152] The above is a further detailed description of the present application in combination with specific preferred embodiments, and the specific implementation of the present application should not be limited to these descriptions. For those of ordinary skill in the art to which the present application belongs, several simple deductions or substitutions can be made without departing from the concept of the present application, and all of them should be considered to fall within the protection scope of the present application.

Claims

1. A method for predicting the far field of a flexible antenna after deformation, characterized in that, The method comprises the following steps: Initialize the target parameters of the flexible antenna, the target parameters of the flexible antenna include N Each of the initial current modes includes 1 initial current mode. A The current vector, the th _ a The initial spatial positions of the current vectors are , No. a The initial spatial orientation of the current vectors is , No. a The initial start coordinates and initial end coordinates of the current vectors are respectively and The thicknesses of the flexible antenna at the initial starting point coordinates and the initial ending point coordinates are respectively and The flexible antenna has a curved surface that produces deformation. The coordinates of the nth sampling point, the th OK Sampling points of the column The coordinates are The incident electric field in the dielectric region of the flexible antenna is The incident magnetic field in the dielectric region of the flexible antenna is The incident electric field of the metal region of the flexible antenna is ;in, , , , ; Based on the target parameters of the flexible antenna, a first change amount and a second change amount of each of the current vectors after deformation of the flexible antenna are obtained, the first change amount being a change amount of an initial spatial position of the current vector , and the second change amount being a change amount of an initial spatial attitude of the current vector . ​​ obtaining a current mode of the deformed flexible antenna based on a first variation and a second variation of each of the current vectors; obtaining a prediction result of a radiation field of the deformed flexible antenna based on the current mode of the deformed flexible antenna, an impedance operator matrix and a target parameter of the flexible antenna.

2. The method of claim 1, wherein, The method comprises the following steps: based on the coordinates of the sampling points on the curved surface where the flexible antenna generates deformation and two-dimensional non-uniform rational B spline basis functions, calculating the curved surface equation where the flexible antenna generates deformation; calculating a starting point coordinate of each of the current vectors of the deformed flexible antenna based on the surface equation, an initial starting point coordinate of each of the current vectors and a thickness of the flexible antenna at each of the initial starting point coordinates; calculating a terminal point coordinate of each of the current vectors of the deformed flexible antenna based on the surface equation, an initial terminal point coordinate of each of the current vectors and a thickness of the flexible antenna at each of the initial terminal point coordinates; calculating the first variation and the second variation of each of the current vectors of the deformed flexible antenna based on the starting point coordinate of each of the current vectors of the deformed flexible antenna and the initial starting point coordinate of the corresponding current vector, the terminal point coordinate of each of the current vectors of the deformed flexible antenna and the initial terminal point coordinate of the corresponding current vector.

3. The method of claim 2, wherein the step of determining the radiation pattern of the flexible antenna after deformation is performed by: The calculation formula of the surface equation of the deformed flexible antenna is as follows: wherein, a curved surface equation generating deformation for the flexible antenna, are two-dimensional non-uniform rational B spline basis functions, and are two-dimensional non-uniform rational B spline basis functions in each dimension, is a coordinate of a row column of sampling points, , is a coordinate of a , or a coordinate of a , .

4. The method of claim 2, wherein the step of determining the radiation pattern of the flexible antenna after deformation is performed by: The calculation formula of the starting point coordinate of the current vector and the terminal point coordinate of the current vector is as follows: wherein, is a starting point coordinate of the current vector, is a curved surface equation that generates deformation of the flexible antenna, is a modulo operation, is an ending point coordinate of the current vector.

5. The method of claim 2, wherein the step of determining the radiation pattern of the flexible antenna after deformation is performed by: a first change amount of the current vector and a second change amount are respectively wherein, is a first change of the current vector, is a modulo operation, is a second change of the current vector, is a starting point coordinate of the current vector, is an end point coordinate of the current vector.

6. The method of claim 1, wherein, The calculation formula of the current mode of the deformed flexible antenna is as follows: wherein, is the current pattern of the flexible antenna after deformation, and are rotation matrices that rotate each of the current vectors along the positive direction of the axis of the length of the flexible antenna and the positive direction of the axis perpendicular to the upper surface of the flexible antenna, pointing to the radiation direction of the flexible antenna, respectively, by and , and is the positive direction of the axis of the length of the flexible antenna, and is the positive direction of the axis perpendicular to the upper surface of the flexible antenna, pointing to the radiation direction of the flexible antenna, is the initial current pattern of the flexible antenna, is the Dirichlet sampling function, is the spatial position of each of the current vectors of the flexible antenna after deformation.

7. The method of claim 1, wherein, The method comprises the following steps: calculating a target impedance matrix based on the current mode of the deformed flexible antenna and the impedance operator matrix; based on the current pattern of the flexible antenna after deformation, the incident electric field of the flexible antenna medium region , the incident magnetic field of the flexible antenna medium region and the incident electric field of the flexible antenna metal region , the target excitation matrix is calculated; calculating a target weight coefficient based on the target impedance matrix and the target excitation matrix; calculating a radiation field of the deformed flexible antenna based on the target weight coefficient and the current mode of the deformed flexible antenna.

8. The method of claim 7, wherein, The calculation formula of the target impedance matrix is as follows: wherein is the target impedance matrix ， ~ ~ is the impedance matrix for each two current modes of the deformed flexible antenna wherein is the impedance matrix of the first m current mode and the first n current mode after deformation of the flexible antenna ， is the first m current mode after deformation of the flexible antenna, is the first n current mode after deformation of the flexible antenna, is the impedance operator matrix, is an inner product operation; wherein, and are identity and zero matrices, respectively, is a matrix obtained by establishing an electric field integral equation and a magnetic field integral equation on an outer surface of the flexible antenna medium region, is a matrix obtained by establishing an electric field integral equation and a magnetic field integral equation on an inner surface of the flexible antenna medium region and an electric field integral equation on an inner surface of the flexible antenna metal region, is a conjugate transpose operation; where is the imaginary unit, is the angular velocity of the electromagnetic wave, and are the permittivity in vacuum and in air, respectively, and are the permeability in vacuum and in the medium, respectively, and are the integral operators representing the field source relation in a homogeneous infinite space, is the Hamiltonian operator, is the wave number of the electromagnetic wave, is the dyadic Green function, is the Cauchy principal value of the integral.

9. The method of claim 7, wherein the step of determining the radiation pattern of the flexible antenna after deformation is performed by: The calculation formula of the target excitation matrix is as follows: wherein, is the target excitation matrix, ~ ~ is the excitation matrix for each current mode of the deformed flexible antenna. wherein is the excitation matrix of the deformed flexible antenna for the m th current mode, is the deformed flexible antenna for the m th current mode, is the initial excitation matrix, is the inner product operation, and are the identity and zero matrices, respectively, is a matrix obtained by establishing electric and magnetic field integral equations on the outer surface of the flexible antenna medium region, is the take conjugate transpose operation.

10. The method of claim 7, wherein, The calculation formula of the target weight coefficient and the radiation field of the deformed flexible antenna is as follows: wherein, is the target weight coefficient, ~ ~ is the weight coefficient for each current mode of the flexible antenna after deformation. wherein, is a weight coefficient of the m-th current mode of the deformed flexible antenna, n is an excitation matrix of the m-th current mode of the deformed flexible antenna, is an impedance matrix of the m-th current mode and the n-th current mode of the deformed flexible antenna, m is an impedance matrix of the m-th current mode and the n-th current mode of the deformed flexible antenna, n is an impedance matrix of the m-th current mode and the n-th current mode of the deformed flexible antenna, is an inverse of is an inverse of is an excitation matrix of the m-th current mode of the deformed flexible antenna, m is an excitation matrix of the m-th current mode of the deformed flexible antenna, wherein, is the deformed radiation field of the flexible antenna, is the imaginary unit, is the angular velocity of the electromagnetic wave, is the magnetic permeability in vacuum medium, is the dyadic Green's function, is the target weight coefficient, is the deformed current mode of the flexible antenna.

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