Lorentz dispersion time-varying metamaterial design method and system, terminal and medium

Abstract

The invention discloses a Lorentz dispersion time-varying metamaterial design method and system, a terminal and a medium. The Lorentz dispersion time-varying metamaterial design method comprises the steps that a mapping relation equation between electromagnetic parameters of a Lorentz dispersion medium and circuit parameters of a second-order oscillation circuit is established; designing a static circuit model based on the mapping relation equation; introducing a time variable into the static circuit model to obtain a target time function; designing a branch circuit and a microcontroller switch of the second-order oscillation circuit according to the target time function; and according to the static circuit model, the branch circuit and the microcontroller switch, constructing a dynamic circuit model, and based on the dynamic circuit model, adjusting on and off of the branch circuit through the microcontroller switch to obtain the target design time-varying metamaterial. According to the invention, the regulation and control means can be simplified, the capability of processing the dispersion effect is improved, and the Lorentz dispersion time-varying metamaterial is realized.

Description

Technical Field

[0001] The present application relates to the technical field of time-varying metamaterial design, and particularly to a design method, system, terminal and medium for Lorentz-dispersive time-varying metamaterials. Background Art

[0002] Metamaterial technology is a miraculous technology that uses artificially designed microstructures, arranges these microstructures, and finally realizes many applications, such as invisibility, and the regulation of the amplitude, phase, polarization, etc. of electromagnetic waves. The target characteristics achieved by metamaterial technology mainly depend on the structure, material properties of the artificially designed microstructures, and the arrangement of these microstructures, such as periodic arrangement. At present, with the continuous improvement of the theory in the field of nanoscience and the continuous breakthrough of experimental technology, more and more people are gradually turning their attention to the dynamic modulation of metamaterials, that is, the realization of time-varying metamaterials. Compared with traditional metamaterials, time-varying metamaterials require the structure or material properties of artificial microstructures to be dynamically modulated over time. The time-varying metamaterial technology with dynamic modulation can break through the Bode-Fano limit of the traditional impedance matching network in the circuit field, break through the Chu-Harrington limit between the antenna bandwidth and gain in the antenna field, and break through the Rozanov limit existing between the material thickness and absorption effect in the absorbing material field, etc. In recent years, with the continuous breakthrough of micro-nano scale technology, the main constraint condition of the research frequency band of time-varying metamaterial technology - the speed at which time-varying metamaterials change over time is constantly increasing. So far, in the microwave band, time-varying metamaterials have been realized using active element circuit units composed of devices such as capacitors and inductors, and in the optical band, time-varying metamaterials have been realized using the absorption characteristics such as the stimulated emission of plasma materials. However, compared with using plasma materials, using circuit units composed of active elements can undoubtedly realize the target time-varying metamaterials more simply and accurately, and the frequency band realized by the circuit units is in the microwave band, which can undoubtedly endow more components and devices required by the Internet field, such as antennas, with time-varying metamaterial technology.

[0003] At present, the research on time-varying metamaterial technology mainly focuses on the realization under the condition of almost no dispersion, and the dispersion effect is treated as almost non-dispersive. However, since the time-varying metamaterial technology will change the frequency of electromagnetic waves and produce a significant dispersion effect during the dynamic modulation process. At this time, ignoring the dispersion effect will result in a large theoretical error and cause a great deviation in the characteristics of the designed target time-varying metamaterials, failing to meet the design requirements.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0005] The main objective of this application is to provide a design method, system, terminal, and medium for Lorentz-dispersive time-varying metamaterials, aiming to solve the problem in the prior art that significant dispersion effects occur during the dynamic modulation process when implementing time-varying metamaterials, resulting in a large deviation between the design target and the actual effect.

[0006] In the first aspect of the embodiments of this application, a design method for Lorentz-dispersive time-varying metamaterials is provided. The design method for Lorentz-dispersive time-varying metamaterials includes the following steps: establishing a mapping relationship equation between the electromagnetic parameters of a Lorentz-dispersive medium and the circuit parameters of a second-order oscillation circuit; designing a static circuit model based on the mapping relationship equation; introducing a time variable into the static circuit model to obtain a target time function; designing the branch circuit and microcontroller switch of the second-order oscillation circuit according to the target time function; constructing a dynamic circuit model based on the static circuit model, the branch circuit, and the microcontroller switch, and adjusting the on and off of the branch circuit through the microcontroller switch based on the dynamic circuit model to obtain the target designed time-varying metamaterial.

[0007] Optionally, in an embodiment of this application, the electromagnetic parameters include the plasma frequency and the resonance frequency, and the circuit parameters include the inductance value and the capacitance value; the establishment of the mapping relationship equation between the electromagnetic parameters of the Lorentz-dispersive medium and the circuit parameters of the second-order oscillation circuit specifically includes: establishing the first electrode polarization response equation of the Lorentz-dispersive medium and the second electrode polarization response equation of the second-order oscillation circuit; establishing a mapping relationship equation between the plasma frequency and resonance frequency of the Lorentz-dispersive medium and the inductance value and capacitance value of the second-order oscillation circuit according to the first electrode polarization response equation and the second electrode polarization response equation.

[0008] Optionally, in an embodiment of this application, the mapping relationship equation is expressed as:

[0009]

[0010] where L is the inductance value of the second-order oscillation circuit, ε0 is the vacuum conductivity, ω p is the plasma frequency of the Lorentz-dispersive medium, C is the capacitance value of the second-order oscillation circuit, and ω0 is the resonance frequency of the Lorentz-dispersive medium.

[0011] Optionally, in an embodiment of this application, the designing of the static circuit model based on the mapping relationship equation specifically includes: determining the target inductance value and target capacitance value of the second-order oscillation circuit based on the mapping relationship equation; obtaining the static circuit model for simulating the Lorentz-dispersive medium according to the target inductance value and the target capacitance value.

[0012] Optionally, in an embodiment of the present application, the target time function includes an inductance time function and a capacitance time function; the introducing of the time variable into the static circuit model to obtain the target time function specifically includes: introducing the time variable into the plasma frequency and the resonance frequency of the Lorentz dispersion medium respectively to obtain a first time function and a second time function; based on the static circuit model, obtaining the inductance time function and the capacitance time function according to the first time function and the second time function.

[0013] Optionally, in an embodiment of the present application, the designing of the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function specifically includes: obtaining the arrangement mode of the inductance time function and the capacitance time function changing with time; if the arrangement mode is a periodic arrangement, designing the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the periodic arrangement.

[0014] Optionally, in an embodiment of the present application, the dynamic circuit model includes a first time-varying unit and a second time-varying unit; the constructing of the dynamic circuit model according to the static circuit model, the branch circuit and the microcontroller switch is specifically: controlling the on and off of the branch circuit in the static circuit model through the microcontroller switch at a preset moment within a unit period to obtain the first time-varying unit and the second time-varying unit.

[0015] The second aspect of the embodiments of the present application further provides a design system for a Lorentz dispersion time-varying metamaterial, wherein the design system for the Lorentz dispersion time-varying metamaterial includes:

[0016] A mapping relationship establishing module, configured to establish a mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit;

[0017] A static circuit model designing module, configured to design a static circuit model based on the mapping relationship equation;

[0018] A time variable introducing module, configured to introduce a time variable into the static circuit model to obtain a target time function;

[0019] A circuit branch and switch designing module, configured to design the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function;

[0020] A circuit model implementing module, configured to construct a dynamic circuit model according to the static circuit model, the branch circuit and the microcontroller switch, and based on the dynamic circuit model, adjust the on and off of the branch circuit through the microcontroller switch to obtain the target designed time-varying metamaterial.

[0021] In a third aspect of the embodiments of the present application, a terminal is further provided. The terminal includes a memory, a processor, and a design program of a Lorentz-dispersive time-varying metamaterial stored on the memory and executable on the processor. When the design program of the Lorentz-dispersive time-varying metamaterial is executed by the processor, the steps of the design method of the Lorentz-dispersive time-varying metamaterial described above are implemented.

[0022] In a fourth aspect of the embodiments of the present application, a computer-readable storage medium is further provided. The computer-readable storage medium stores a design program of a Lorentz-dispersive time-varying metamaterial. When the design program of the Lorentz-dispersive time-varying metamaterial is executed by a processor, the steps of the design method of the Lorentz-dispersive time-varying metamaterial described above are implemented.

[0023] Beneficial effects: The present application provides a design method, system, terminal, and medium for a Lorentz-dispersive time-varying metamaterial. By establishing the connection between the Lorentz-dispersive medium and the second-order oscillating circuit, the present application converts the periodic dynamic regulation of circuit parameters (the magnitudes of capacitance and inductance) into the dynamic regulation of the on-off of the electric inductance branch, thereby simplifying the regulation means, enhancing the integration ability of the time-varying active element circuit, improving the ability to handle the dispersion effect, and realizing the Lorentz-dispersive time-varying metamaterial. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings described below are only some embodiments recorded in the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0025] Figure 1 is a flowchart of a preferred embodiment of the design method of the Lorentz-dispersive time-varying metamaterial of the present application;

[0026] Figure 2 is a schematic diagram of the structure of a Lorentz-dispersive time-varying metamaterial with a periodic arrangement of one-dimensional artificial microstructural time-varying units;

[0027] Figure 3 is an active element circuit model diagram of the Lorentz-dispersive time-varying metamaterial realized by the artificial microstructural time-varying unit in a preferred embodiment of the design method of the Lorentz-dispersive time-varying metamaterial of the present application;

[0028] Figure 4 is for Figure 3 a model diagram for schematically showing the meandering copper wire in the active element circuit model;

[0029] Figure 5Schematic diagram of the Lorentz-dispersive time-varying metamaterial of the preferred embodiment of the design system of the Lorentz-dispersive time-varying metamaterial of the present application;

[0030] Figure 6 Structural diagram of the preferred embodiment of the design system of the Lorentz-dispersive time-varying metamaterial of the present application;

[0031] Figure 7 Structural diagram of the preferred embodiment of the terminal of the present application.

[0032] Explanation of reference numerals:

[0033] 100, mapping relationship establishment module; 200, static circuit model design module; 300, time variable introduction module; 400, circuit branch and switch design module; 500, circuit model implementation module. Detailed implementation manners

[0034] To make the objectives, technical solutions and effects of the present application clearer and more definite, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present application. The described embodiments are only possible technical implementations of the present application, not all possible implementations. Based on the embodiments in the present application, those skilled in the art can fully combine the embodiments of the present application to obtain other embodiments without creative labor, and these embodiments are also within the protection scope of the present application.

[0035] The inventive concept of the present application is to design a time-varying dispersive metamaterial by using the impedance of a microwave circuit. In the embodiments of the present application, the Lorentz-type dispersion relationship is realized by adjusting the capacitance and inductance in the oscillation circuit model of the microwave circuit, and the time-varying effect is realized by controlling the on-off of the switch; however, it is not limited thereto. In the embodiments of the present application, the Lorentz-dispersive time-varying metamaterial can also be realized by adding or reducing branches or adjusting the impedance.

[0036] The design method, system, terminal and medium of the Lorentz-dispersive time-varying metamaterial in the embodiments of the present application will be described below with reference to the accompanying drawings. Aiming at the problem in the related art mentioned above that a significant dispersion effect will occur during the dynamic modulation process when realizing a time-varying metamaterial, resulting in a large deviation between the design target and the actual effect, the present application provides a design method of a Lorentz-dispersive time-varying metamaterial. In this method, by establishing the connection between the Lorentz-dispersive medium and the second-order oscillation circuit, the periodic dynamic adjustment of the circuit parameters (the magnitude values of capacitance and inductance) is converted into the dynamic adjustment of the on-off of the electric inductance branch, thereby simplifying the control means, enhancing the integration ability of the time-varying active element circuit, improving the ability to handle the dispersion effect, and realizing the Lorentz-dispersive time-varying metamaterial. Thus, the technical problem in the related art that a significant dispersion effect will occur during the dynamic modulation process when realizing a time-varying metamaterial, resulting in a large deviation between the design target and the actual effect, is solved.

[0037] Based on the equation of the Lorentz dispersion medium and the equation of the capacitance-inductance oscillation circuit corresponding to the microwave circuit, the active element circuit model of the Lorentz dispersion time-varying metamaterial obtained by the present application can design the dispersion effect of the time-varying metamaterial into the artificial microstructure unit, achieving a principled breakthrough. Specifically, starting from the second-order partial differential equation of the Lorentz dispersion medium, by comparing and relating to the second-order oscillation partial differential equation of the capacitance and inductance corresponding to the microwave circuit, the electromagnetic parameters of the artificial microstructure metamaterial in space, such as the dielectric constant, permeability, etc., are mapped into the capacitance and inductance of the second-order oscillation circuit, and the dynamic modulation of the electromagnetic parameters of the metamaterial in space over time is converted into the dynamic modulation of the capacitance and inductance in the second-order oscillation circuit over time. The specific modulation method is to control the on and off of the branch circuit of the second-order oscillation circuit, and finally, the dispersion time-varying metamaterial in the microwave band is realized by using the active element circuit model of the Lorentz dispersion medium. Compared with the oscillation circuit that does not consider the dispersion effect of the time-varying metamaterial, the present application considers the dispersion effect and realizes a circuit model scheme for the dispersion time-varying metamaterial in the microwave band.

[0038] The technical solution of the present application will be described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be repeated in some embodiments.

[0039] The design method of the Lorentz dispersion time-varying metamaterial according to the preferred embodiment of the present application, as Figure 1 shown, the design method of the Lorentz dispersion time-varying metamaterial includes the following steps:

[0040] In step S101, establish a mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit.

[0041] It should be noted that in the design of the Lorentz dispersion time-varying metamaterial, there are mainly two aspects: one is the design of the time-varying unit of the artificial microstructure, and the other is the arrangement method of the time-varying unit of the artificial microstructure. The present application mainly relates to the design of the time-varying unit of the artificial microstructure, and the arrangement method of the remaining time-varying units of the artificial microstructure is default selected as one-dimensional periodic arrangement. For the schematic diagram of the specific time-periodic time-varying metamaterial, see Figure 2 , and the length corresponding to the specific number of periods should be 3-4 times the wavelength corresponding to the target frequency.

[0042] The design steps of the artificial microstructure unit designed by the present application can be mainly divided into two steps. The first step (steps S101 and S102) is to design the static artificial microstructure unit (i.e., obtained by designing the static circuit model), and the second step (steps S103 and S105) is the time-varying scheme of the artificial microstructure unit.

[0043] It is understandable that the microstrip line fabricated by etching is a kind of microwave circuit, and its equivalent circuit model is a second-order oscillation circuit model.

[0044] In a possible implementation, the electromagnetic parameters include the plasma frequency and the resonance frequency, and the circuit parameters include the inductance value and the capacitance value. Establish the first electrode polarization response equation of the Lorentz dispersion medium and the second electrode polarization response equation of the second-order oscillation circuit; according to the first electrode polarization response equation and the second electrode polarization response equation, establish the mapping relationship equation between the plasma frequency and the resonance frequency of the Lorentz dispersion medium and the inductance value and the capacitance value of the second-order oscillation circuit.

[0045] In the first step, design the circuit model unit of the Lorentz dispersion medium artificial microstructure unit. Specifically, in order to simplify the design without affecting the dispersion effect, design a Lorentz dispersion medium with negligible loss. The relative conductivity of the Lorentz dispersion medium with frequency ω is given by the following formula:

[0046]

[0047] where ε is the vacuum conductivity, ω p , ω0 are the plasma frequency and the resonance frequency of the Lorentz dispersion medium respectively. When the Lorentz dispersion medium is under the action of an external electric field, the relationship between its electrode polarization response and the electric field strength of the external electric field will satisfy a second-order partial differential equation. The expression of this second-order partial differential equation (i.e., the first electrode polarization response equation) is as follows:

[0048]

[0049] where P and E are the electrode polarization response of the Lorentz dispersion medium and the electric field strength of the external electric field respectively, and ε0 is the vacuum conductivity. Comparing with equation (2), the second-order partial differential equation (i.e., the second electrode polarization response equation) satisfied by the electrode polarization response and the electric field strength of the external electric field of the capacitance-inductance oscillation circuit unit of the microwave circuit can be expressed as follows:

[0050]

[0051] where L and C are the inductance value and the capacitance value of the second-order oscillation circuit respectively. Connecting equations (2) and (3), the relationship between the plasma frequency and the resonance frequency of the Lorentz dispersion medium and the inductance and capacitance values of the second-order oscillation circuit can be obtained as follows:

[0052]

[0053] Therefore, according to the mapping relationship equation (4), the Lorentz dispersion medium can be realized by a second-order oscillation circuit model, and the plasma frequency and resonance frequency of the Lorentz dispersion medium can be adjusted by adjusting the inductance and capacitance values of the second-order oscillation circuit.

[0054] It can be understood that to determine the electromagnetic properties of the Lorentz dispersion medium and clarify the relative conductivity formula equation (1) of the Lorentz dispersion medium, which describes the relationship between the electromagnetic response of the medium and frequency; to derive the second-order partial differential equation (2) between the polarization response and the electric field strength of the Lorentz dispersion medium under the action of an external electric field, which describes the dynamic electromagnetic properties of the medium; to compare the second-order partial differential equation (3) of the capacitance-inductance oscillation circuit unit of the microwave circuit under the action of an external electric field, which describes the dynamic behavior of charges or currents in the circuit; by comparing the second-order partial differential equations of the Lorentz dispersion medium and the capacitance-inductance oscillation circuit, it is found that they are similar in form, both containing a second derivative term and a term related to frequency or circuit parameters. Based on this similarity, the plasma frequency and resonance frequency of the Lorentz dispersion medium are analogized with the inductance and capacitance values of the capacitance-inductance oscillation circuit, and the mapping relationship equation (4) between the electromagnetic parameters (plasma frequency and resonance frequency) of the Lorentz dispersion medium and the inductance and capacitance values in the microwave circuit is established.

[0055] In step S102, based on the mapping relationship equation, a static circuit model is designed.

[0056] In a possible implementation manner, based on the mapping relationship equation, the target inductance value and the target capacitance value of the second-order oscillation circuit are determined; according to the target inductance value and the target capacitance value, a static circuit model for simulating the Lorentz dispersion medium is obtained.

[0057] Specifically, the plasma frequency and resonance frequency are determined by the determined capacitance value and inductance value. Since the final magnitudes of the capacitance value and inductance value need to conform to the value selection range of general devices, the plasma frequency and resonance frequency of the Lorentz dispersion medium are determined, and then the target capacitance value and the target inductance value are determined.

[0058] It can be understood that according to the electromagnetic parameters (such as permittivity and permeability) of the Lorentz dispersion medium, the corresponding circuit element values (inductance value and capacitance value) are determined through equation conversion; a static circuit model is designed, and this model can simulate the electromagnetic response of the Lorentz dispersion medium, that is, a second-order oscillation circuit with fixed inductance and capacitance values is used to simulate the static Lorentz dispersion medium.

[0059] In step S103, a time variable is introduced into the static circuit model to obtain a target time function.

[0060] It should be noted that the second step (step S103 - step S105) is a time-varying scheme for artificial microstructural units. Since the design goal is a time-varying metamaterial, the artificial microstructural units of the metamaterial must change dynamically over time.

[0061] In a possible implementation, the target time function includes an inductance time function and a capacitance time function. By introducing the time variable into the plasma frequency and resonance frequency of the Lorentz dispersion medium respectively, the first time function and the second time function are obtained; based on the static circuit model, according to the first time function and the second time function, the inductance time function and the capacitance time function are obtained.

[0062] It can be understood that since the goal is to design a time-varying metamaterial, the artificial microstructural units must change dynamically over time. By introducing the time variable, the electromagnetic parameters of the Lorentz dispersion medium become functions of time, thus realizing the time-varying metamaterial.

[0063] Specifically, the artificial microstructural units of the metamaterial must change dynamically over time. Therefore, the plasma frequency and resonance frequency of the above-mentioned Lorentz dispersion medium, and the values of the inductance and capacitance of the second-order oscillation circuit will all be functions of time, that is, the first time function ω p (t), the second time function ω0(t), the inductance time function L(t), and the capacitance time function C(t). Since the arrangement of the time-varying metamaterial selected in the embodiments of the present application changes periodically over time, the above parameters ω p (t), ω0(t), L(t), C(t) will all change periodically over time.

[0064] In step S104, design the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function.

[0065] In a possible implementation, obtain the arrangement of the inductance time function and the capacitance time function that changes over time; if the arrangement is a periodic arrangement, then design the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the periodic arrangement.

[0066] It can be understood that since it is relatively difficult to directly implement the inductance and capacitance values that change periodically over time, it is proposed to achieve this goal by controlling the on and off of the branch circuit of the microwave circuit; design specific circuit branches and microcontroller switches to ensure that the inductance and capacitance values change periodically over time.

[0067] Specifically, in the actual implementation process, it is very difficult to design according to the periodically changing ω p(t), ω0(t) This design goal requires L(t) and C(t) in the circuit to change periodically with time. Even for some dynamic inductors and capacitors, it is only possible to change with time and it is very difficult to change periodically with time. To avoid this problem, the embodiment of the present application designs the circuit branches of the second-order oscillation circuit, and controls the periodic change of the on and off states of the branch circuit through the microcontroller switch, so as to realize the periodic change of the inductance and capacitance values L(t) and C(t) in the circuit with time.

[0068] It should be noted that the present application associates the plasma frequency and resonance frequency of the Lorentz dispersion medium with the capacitance and inductance of the second-order oscillation circuit. The resonance circuit constructed by the capacitance and inductance can realize the Lorentz-type dispersion relationship; the periodic dynamic adjustment of the capacitance and inductance values is converted into the dynamic adjustment of the on and off of the capacitance and inductance branch circuits, and the originally complex adjustment scheme using dynamic capacitors or dynamic inductors is changed to simply controlling the on and off of the circuit, greatly simplifying the control means and greatly enhancing the integration ability of realizing the time-varying active element circuit.

[0069] In step S105, according to the static circuit model, the branch circuit and the microcontroller switch, a dynamic circuit model is constructed. Based on the dynamic circuit model, the on and off of the branch circuit are adjusted through the microcontroller switch to obtain the target designed time-varying metamaterial.

[0070] In a possible implementation manner, the dynamic circuit model includes a first time-varying unit and a second time-varying unit. At a preset moment within a unit period, the on and off of the branch circuit in the static circuit model are controlled through the microcontroller switch to obtain the first time-varying unit and the second time-varying unit.

[0071] Specifically, the circuit model diagram is as Figure 3 and Figure 4 shown, Figure 4 The left part of the polygonal wire frame is a meandering copper wire. Among them, E(z,t) and H(z,t) are used to describe the electric field strength and magnetic field strength in the microwave circuit corresponding to the circuit model specifically in the microwave band. Δz represents the circuit length of a time-varying artificial microstructure unit. L0 and C0 respectively correspond to the conductivity and magnetic permeability in vacuum; L1 (target inductance value) and C a (target capacitance value) branches plus the C0 (capacitance value in vacuum) branch can realize a Lorentz-type dispersion curve, corresponding to Figure 2 the time-varying unit 1 (i.e., the first time-varying unit) in; L1 and C b (capacitance value in the branch circuit) branches plus the C0 branch can realize another profile of the Lorentz-type dispersion curve, corresponding to Figure 2The time-varying unit 2 (i.e., the second time-varying unit) therein; by periodically controlling the switch to be connected to C at the moment when the time ratio in a certain unit period is t = t1 (t is the unit period and t1 is the preset moment). a and C b , the periodic transformation between different line shapes of the Lorentz dispersion curve can be realized.

[0072] Figure 5 Figure is a schematic diagram of the Lorentz dispersion time-varying metamaterial. The overall structure is a printed circuit board with a size of 8 cm × 20 cm. The signal input port of the structure is in the middle of the leftmost side, and the signal output port is in the middle of the rightmost side. The left input port and the right output port are connected by a meandering microstrip line. A microcontroller is connected at the upper corner of the meandering microstrip line to control the on and off of the capacitor branch on the left side of the microcontroller and the inductor and capacitor branches above. The ten microcontrollers above are collectively controlled through the port in the upper left corner. Similarly, a microcontroller is connected at the lower corner of the meandering microstrip line to control the on and off of the capacitor branch on the left side of the microcontroller and the inductor and capacitor branches below. The ten microcontrollers below are collectively controlled through another port in the lower left corner. Among them, the capacitance values of the capacitor branches connected to the upper and lower microcontrollers, and the inductance values and capacitance values of the inductor and capacitor branches are all different. In the specific implementation process, electromagnetic waves are incident from the left input port and transmitted in the meandering microstrip line. Since the electromagnetic waves are confined in the meandering microstrip line, the microstrip line can simulate an infinite space medium. During the transmission process, through the signal control ports of the upper and lower microcontrollers, the on and off of the upper and lower capacitor branches and the upper and lower inductor and capacitor branches, a total of four branches, can be controlled. When only one capacitor branch is on, the whole structure is a non-dispersive and time-invariant structure. By quickly controlling another capacitor branch to be connected at a certain moment in addition to the already connected capacitor branch, the increased capacitor branch causes an instantaneous change in the impedance of the whole structure, thereby realizing the time reflection and time transmission of the time-varying metamaterial. At this time, the whole structure can be confirmed as a non-dispersive time-varying metamaterial. When the whole structure quickly connects an inductor and capacitor branch at a certain moment in addition to connecting one capacitor branch, the increased inductor and capacitor branch makes the whole structure exhibit Lorentz dispersion. Furthermore, the whole structure can be used to realize the Lorentz dispersion time-varying metamaterial. Moreover, by using periodic input control signals at the ports in the upper left corner and the lower left corner, the periodic on-off conversion of the first capacitor branch and the second capacitor branch can be controlled, thereby realizing the non-dispersive photonic time crystal. Controlling the periodic on-off conversion of the first inductor and capacitor branch and the second inductor and capacitor branch can realize the Lorentz dispersion photonic time crystal.

[0073] This application realizes the Lorentz dispersion curve shape corresponding to different plasma frequencies and resonance frequencies by adjusting the values of capacitors and inductors, and realizes the Lorentz dispersion time-varying metamaterial by controlling the on / off of the capacitor and inductor branches. In principle, Figure 3 and Figure 4 only represent one way of realizing the Lorentz dispersion time-varying metamaterial through an active element circuit, and should not be construed as a limitation to this application. This application realizes the Lorentz dispersion type curve by adjusting the sizes of different capacitor or inductor components, and can also realize the Lorentz dispersion type curve by increasing or decreasing the number of branches and adjusting the positions of capacitors or inductors in the oscillation circuit model.

[0074] Based on the above embodiments, this application also provides a Lorentz dispersion time-varying metamaterial, wherein the Lorentz dispersion time-varying metamaterial is designed according to the design method of the Lorentz dispersion time-varying metamaterial described in any one of the above solutions.

[0075] Next, a design system of the Lorentz dispersion time-varying metamaterial proposed according to an embodiment of this application will be described with reference to the accompanying drawings.

[0076] Figure 6 is a structural diagram of the design system of the Lorentz dispersion time-varying metamaterial of an embodiment of this application.

[0077] As Figure 6 shown, the design system of the Lorentz dispersion time-varying metamaterial includes: a mapping relationship establishment module 100, a static circuit model design module 200, a time variable introduction module 300, a circuit branch and switch design module 400, and a circuit model implementation module 500.

[0078] Specifically, the mapping relationship establishment module 100 is used to establish a mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit;

[0079] The static circuit model design module 200 is used to design a static circuit model based on the mapping relationship equation;

[0080] The time variable introduction module 300 is used to introduce a time variable into the static circuit model to obtain a target time function;

[0081] The circuit branch and switch design module 400 is used to design the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function;

[0082] The circuit model implementation module 500 is used to construct a dynamic circuit model according to the static circuit model, the branch circuit, and the microcontroller switch, and based on the dynamic circuit model, adjust the on and off of the branch circuit through the microcontroller switch to obtain the target designed time-varying metamaterial.

[0083] Figure 7 This is the structural diagram of the terminal provided by the embodiments of the present application. The terminal may include:

[0084] A memory 501, a processor 502, and a computer program stored on the memory 501 and executable on the processor 502.

[0085] When the processor 502 executes the program, it implements the design method of the Lorentz dispersion time-varying metamaterial provided in the above embodiments.

[0086] Furthermore, the terminal further includes:

[0087] A communication interface 503 for communication between the memory 501 and the processor 502.

[0088] The memory 501 is used to store a computer program executable on the processor 502.

[0089] The memory 501 may include a high-speed RAM memory, and may also include a non-volatile memory, such as at least one disk memory.

[0090] If the memory 501, the processor 502, and the communication interface 503 are implemented independently, the communication interface 503, the memory 501, and the processor 502 may be interconnected through a bus and communicate with each other. The bus may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. The bus may be divided into an address bus, a data bus, a control bus, etc. For the sake of representation, Figure 7 only a thick line is used to represent it in the figure, but it does not mean that there is only one bus or one type of bus.

[0091] Optionally, in a specific implementation, if the memory 501, the processor 502, and the communication interface 503 are integrated on a chip, the memory 501, the processor 502, and the communication interface 503 may communicate with each other through an internal interface.

[0092] The processor 502 may be a Central Processing Unit (CPU), or an Application Specific Integrated Circuit (ASIC), or one or more integrated circuits configured to implement the embodiments of the present application.

[0093] This embodiment also provides a computer-readable storage medium, on which a computer program is stored. When the program is executed by a processor, it implements the design method of the Lorentz dispersion time-varying metamaterial as described above.

[0094] An embodiment of the present application provides a computer program product, including a computer program, which when executed by a processor, implements the design method of the Lorentz dispersion time-varying metamaterial provided in any of the embodiments corresponding to the present application Figure 1 as described in the embodiments provided in the embodiments corresponding to the present application.

[0095] In the description of this specification, the descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc., mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, without conflict, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0096] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present application, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0097] Any process or method description shown in a flowchart or described in other ways herein may be understood as representing a module, segment, or part of code including one or N executable instructions for implementing a customized logic function or process. The scope of the preferred embodiments of the present application includes additional implementations, where the functions may be executed in a substantially simultaneous manner or in a reverse order according to the involved functions, rather than in the order shown or discussed, which should be understood by those skilled in the art of the embodiments of the present application.

[0098] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definable sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable storage medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatus, or devices. For the purposes of this specification, a "computer-readable storage medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable storage media include the following: an electrical connection portion (electronic device) having one or N wirings, a portable computer disk cartridge (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable storage medium can even be paper or other suitable media on which the program can be printed, because the program can be obtained electronically by optically scanning the paper or other media, followed by editing, interpretation, or otherwise processing as appropriate, and then storing it in a computer memory.

[0099] It should be understood that the various parts of the present application can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application-specific integrated circuits having appropriate combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

[0100] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above embodiments can be completed by a program instructing relevant hardware, and the program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0101] In addition, each functional unit in various embodiments of the present application may be integrated into a processing module, or each unit may exist physically alone, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0102] The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disc, etc. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present application. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present application.

[0103] It should be understood that the application of the present application is not limited to the above examples. For those of ordinary skill in the art, improvements or transformations can be made according to the above description, and all such improvements and transformations should fall within the protection scope of the appended claims of the present application.

[0104] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application and are not intended to limit them. Although the present application has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features. And these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A design method for a Lorentz dispersion time-varying metamaterial, characterized in that The design method of the Lorentz dispersion time-varying metamaterial includes: Establishing a mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit; Designing a static circuit model based on the mapping relationship equation; Introducing a time variable into the static circuit model to obtain a target time function; Designing the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function; Constructing a dynamic circuit model according to the static circuit model, the branch circuit and the microcontroller switch, and based on the dynamic circuit model, adjusting the on and off of the branch circuit through the microcontroller switch to obtain the target designed time-varying metamaterial.

2. The design method of the Lorentz dispersion time-varying metamaterial according to claim 1, wherein The electromagnetic parameters include the plasma frequency and the resonance frequency, and the circuit parameters include the inductance value and the capacitance value; The establishment of the mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit specifically includes: Establishing a first polarization response equation of the Lorentz dispersion medium and a second polarization response equation of the second-order oscillation circuit; According to the first polarization response equation and the second polarization response equation, establishing a mapping relationship equation between the plasma frequency and the resonance frequency of the Lorentz dispersion medium and the inductance value and the capacitance value of the second-order oscillation circuit.

3. The design method of the Lorentz dispersion time-varying metamaterial according to claim 2, characterized in that The mapping relationship equation is expressed as: Among them, L is the inductance value of the second-order oscillation circuit, ε0 is the vacuum conductivity, ω p is the plasma frequency of the Lorentz dispersion medium, C is the capacitance value of the second-order oscillation circuit, and ω0 is the resonance frequency of the Lorentz dispersion medium.

4. The design method of the Lorentz dispersion time-varying metamaterial according to claim 1, characterized in that, The design of the static circuit model based on the mapping relationship equation specifically includes: Based on the mapping relationship equation, determining the target inductance value and the target capacitance value of the second-order oscillation circuit; According to the target inductance value and the target capacitance value, obtaining a static circuit model that simulates the Lorentz dispersion medium.

5. The design method of the Lorentz dispersion time-varying metamaterial according to claim 2, wherein The target time function includes an inductance time function and a capacitance time function; The introduction of the time variable into the static circuit model to obtain the target time function specifically includes: Respectively introducing the time variable into the plasma frequency and the resonance frequency of the Lorentz dispersion medium to obtain a first time function and a second time function; Based on the static circuit model, according to the first time function and the second time function, obtaining the inductance time function and the capacitance time function.

6. The design method of the Lorentz dispersion time-varying metamaterial according to claim 5, wherein, The design of the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function specifically includes: Obtaining the arrangement of the inductance time function and the capacitance time function changing with time; If the arrangement is a periodic arrangement, designing the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the periodic arrangement.

7. The design method of the Lorentz dispersion time-varying metamaterial according to claim 2, characterized in that The dynamic circuit model includes a first time-varying unit and a second time-varying unit; The construction of the dynamic circuit model according to the static circuit model, the branch circuit and the microcontroller switch is specifically: Controlling the on and off of the branch circuit in the static circuit model through the microcontroller switch at a preset moment within a unit period to obtain a first time-varying unit and a second time-varying unit.

8. A design system for a Lorentz dispersion time-varying metamaterial, characterized in that, The design system of the Lorentz dispersion time-varying metamaterial includes: A mapping relationship establishment module for establishing a mapping relationship equation between the electromagnetic parameters of the Lorentz dispersion medium and the circuit parameters of the second-order oscillation circuit; A static circuit model design module for designing a static circuit model based on the mapping relation equation; A time variable introduction module for introducing a time variable into the static circuit model to obtain a target time function; A circuit branch and switch design module for designing the branch circuit and the microcontroller switch of the second-order oscillation circuit according to the target time function; A circuit model implementation module for constructing a dynamic circuit model based on the static circuit model, the branch circuit and the microcontroller switch, and adjusting the on and off of the branch circuit through the microcontroller switch based on the dynamic circuit model to obtain a target designed time-varying metamaterial.

9. A terminal, characterized in that, The terminal includes: a memory, a processor, and a design program of the Lorentz dispersion time-varying metamaterial stored on the memory and executable on the processor. When the design program of the Lorentz dispersion time-varying metamaterial is executed by the processor, the steps of the design method of the Lorentz dispersion time-varying metamaterial according to any one of claims 1-7 are implemented.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a design program of the Lorentz dispersion time-varying metamaterial. When the design program of the Lorentz dispersion time-varying metamaterial is executed by a processor, the steps of the design method of the Lorentz dispersion time-varying metamaterial according to any one of claims 1-7 are implemented.

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