CN-121981051-A - Rectangular waveguide based on electromagnetic outer metamaterial and design method

CN121981051ACN 121981051 ACN121981051 ACN 121981051ACN-121981051-A

Abstract

The invention relates to the technical field of electromagnetic field transmission and waveguide, and discloses a rectangular waveguide based on electromagnetic outer metamaterial and a design method thereof, wherein the outer point frequency is matched with a target screening frequency by adjusting structural parameters of saddle-shaped metal units with D 2d point group symmetry, and the saddle-shaped metal units are periodically arranged along a three-dimensional direction to form a rectangular waveguide nested structure, so that a self-driven frequency selection function is realized; modeling the outer metamaterial waveguide by using CST full-wave simulation software, setting a limited period for the outer metamaterial waveguide along the transmission direction, adopting an x-y-z all-direction open boundary condition to simulate the electromagnetic transmission characteristic of an actual waveguide, calculating the electromagnetic field response of a waveguide fundamental mode, and verifying the self-driving frequency selection function, analyzing the transmission mode of the outer metamaterial waveguide based on a simulation verification result, verifying that the outer metamaterial waveguide is bounded by the outer frequency, and having the frequency selection characteristic of spontaneously suppressing low-frequency signals and conducting high-frequency signals.

Inventors

WANG HANYU
LIN SHIKAI
YANG BIAO
ZHU ZHIHONG
LI PEISHI
LIU YOUMING

Assignees

中国人民解放军国防科技大学

Dates

Publication Date: 20260505
Application Date: 20260408

Claims (10)

1. The design method of the rectangular waveguide based on the electromagnetic outer metamaterial is characterized by comprising the following steps of: s100, constructing a Curie metamaterial waveguide, namely enabling the Curie point frequency to be matched with a target screening frequency by adjusting structural parameters of saddle-shaped metal units with D 2d point group symmetry, and periodically arranging the saddle-shaped metal units with the structural parameters in a three-dimensional direction to form a rectangular waveguide nested structure, so that a self-driven frequency selection function is realized; S200, waveguide simulation verification, namely modeling the outer metamaterial waveguide by using CST full-wave simulation software, setting a limited period for the outer metamaterial waveguide along the transmission direction, adopting an x-y-z all-directional open boundary condition to simulate the electromagnetic transmission characteristic of an actual waveguide, and calculating the electromagnetic field response of a main mode or the electromagnetic field response of a waveguide fundamental mode so as to verify the self-driving frequency selection function; and S300, analyzing the transmission mode of the outer metamaterial waveguide based on a simulation verification result, wherein when the frequency is lower than the outer frequency, the fundamental mode energy is locally near an excitation port, and when the frequency is high Yu Waier, the fundamental mode energy is axially transmitted to an output end along the outer metamaterial waveguide, so that the frequency selection characteristic of spontaneously suppressing a low-frequency signal and conducting a high-frequency signal is verified by taking the outer frequency of the outer metamaterial waveguide as a boundary.
2. The method for designing a rectangular waveguide based on electromagnetic kerr material according to claim 1, wherein step S100 includes kerr metamaterial cell design with specific frequency, specifically: taking a saddle-shaped metal structure with D 2d point group symmetry and breaking space inversion symmetry as a parent cell of a exor metamaterial structure; designing a kernal metamaterial structure primitive cell, wherein the core is a communicated saddle-shaped metal structure, and wrapping an isotropic uniform medium with a supporting function outside; The length-width ratio of the communicated saddle-shaped metal structure is adjusted, namely, lattice constants of the outer metamaterial structure unit cells along different directions are changed, so that the regulation and control of electromagnetic response intensity in all directions in a three-dimensional space and the regulation and control of the position of an outer point on a momentum space high symmetry line and the response frequency of the outer point are realized.
3. The method for designing a rectangular waveguide based on electromagnetic kerr material according to claim 2, wherein step S100 further comprises constructing a kerr material waveguide, specifically: performing structural design on the outer metamaterial waveguide by imitating the metal rectangular waveguide; periodically translating the outer metamaterial unit cells to form outer metamaterial blocks; The outer metamaterial unit cells are periodically arranged along the xy-plane direction to form 4 layers of waveguide walls, and then are enclosed into a rectangular frame, so that a nested rectangular structure of the outer metamaterial unit cells and air is constructed, wherein the air is a guided wave material, the cross section size of an air channel is 3 x 3 unit cell cross section, and the transmission direction of the waveguide is the z direction.
4. The method for designing a rectangular waveguide based on electromagnetic exor metamaterials according to claim 3, wherein the exor metamaterials of the cell periods of the plurality of exor metamaterials are butted with the rectangular frame along the z direction, so that the z direction structure is continuously consistent.
5. The method for designing a rectangular waveguide based on electromagnetic kerr meta-material according to any one of claims 1 to 4, wherein step S200 is specifically: Applying open boundary conditions in the x-y-z direction so as to observe the propagation characteristics of an electromagnetic field in a whole space; The lower interface of the waveguide is provided with a port, the cross section area of the outer metamaterial primitive cell with the area of 3 multiplied by 3, two basic modes are calculated together, and the transmission properties of all modes are completely observed in the mode because the basic modes take the dominant role in energy.
6. The method for designing a rectangular waveguide based on electromagnetic outer metamaterial according to claim 5, wherein the modeling-completed outer metamaterial waveguide is subjected to finite period simulation along the transmission direction so as to simulate the influence of finite number of periods on electromagnetic field transmission in actual conditions; and 10 periods are taken for calculation, an open boundary condition is set along the xyz direction, and a frequency domain solver is applied to calculate a plurality of modes, namely the construction and calculation of the outer metamaterial waveguide are realized.
7. The method for designing a rectangular waveguide based on electromagnetic kerr meta-material according to any one of claims 1 to 4, wherein step S300 is specifically: The transmission characteristic of the outer metamaterial waveguide takes outer frequency as a boundary to present biphase; when the port excitation frequency is lower than the external frequency, the electromagnetic field energy of the excited fundamental mode is sharply attenuated in the transmission process along the axial direction of the waveguide, and the excited fundamental mode is mainly limited to the adjacent area of the excitation port, so that the transmission is restrained; when the port excitation frequency is Yu Waier frequencies high, the fundamental mode propagates axially along the waveguide with very low loss and can be effectively observed at the output port.
8. The method of designing a rectangular waveguide based on electromagnetic kerr meta-material of claim 7 wherein the kerr frequency is tuned based on changing saddle-shaped structure parameters.
9. The method for designing a rectangular waveguide based on an electromagnetic kerr material according to claim 7, wherein in the simulation model, when the length of the waveguide in the z-axis transmission direction is set to 10 kerbs, there are two basic electromagnetic wave modes, mode1 and Mode2, respectively, wherein when the frequency is lower than the kerr frequency, the two basic electromagnetic wave modes are reflected as spontaneous suppression, and when the frequency is higher than Yu Waier, the two basic electromagnetic wave modes are spontaneously propagated; The main electric field vibration direction of Mode 1 is along the x-axis direction, the main electric field vibration direction of Mode 2 is along the y-axis direction, and the electromagnetic field intensity of the two modes is fast attenuated in the z-axis transmission direction along the waveguide; The result shows that the outer metamaterial waveguide has spontaneous frequency selection characteristics, the fundamental mode lower than the outer frequency is spontaneously restrained, the fundamental mode with high Yu Waier frequency is spontaneously conducted, the outer frequency is further regulated by regulating the structural parameters of the outer metamaterial, and a larger regulation and control range is realized.
10. A rectangular waveguide based on electromagnetic kerr metamaterial, which is characterized in that the rectangular waveguide based on electromagnetic kerr metamaterial is designed and prepared by adopting the design method of the rectangular waveguide based on electromagnetic kerr metamaterial as claimed in any one of claims 1 to 9.

Description

Rectangular waveguide based on electromagnetic outer metamaterial and design method Technical Field The invention relates to the technical field of electromagnetic field transmission and waveguide, in particular to a rectangular waveguide based on electromagnetic outer metamaterial and a design method thereof. Background The waveguide is used as a basic electromagnetic waveguide row structure and plays a core role in the fields of microwave engineering, wireless communication, radio frequency systems and the like. The basic principle is that electromagnetic energy is constrained to directionally propagate in a specific space dimension by constructing a specific boundary condition, so that the efficient transmission of energy and information is realized. Common waveguide structures include rectangular metal waveguides, dielectric waveguides, etc., whose performance depends largely on material characteristics and geometry, and have found wide application in various types of communication, sensing, and signal processing systems. However, conventional waveguide structures generally do not have autonomous frequency selection characteristics, and often rely on external filters, switches, or other active control elements to turn on and off signals in a specific frequency band. This not only increases the system complexity and physical size, but also introduces additional insertion loss, cost and control delay. With the increasing demands of modern communication systems for integration, adaptation and versatility, existing waveguides still face significant challenges in achieving built-in, self-driven, frequency selectivity without external excitation. In recent years, novel structures represented by artificial electromagnetic metamaterials provide new ideas for realizing the designable waveguide performance. Through careful structural design, flexible regulation and control of electromagnetic response can be realized in a sub-wavelength scale. However, most of the existing metamaterial waveguides still have limitations in realizing stable and sharp frequency selection functions, such as limited degrees of freedom in regulation and control, insufficient structural robustness, dependence of frequency selection characteristics on external control signals, and the like. Particularly, in the aspect of realizing an intelligent waveguide which takes the intrinsic physical characteristics of materials as a threshold value and can autonomously distinguish and pass/inhibit electromagnetic waves in different frequency bands, a mature and reliable technical scheme is not formed. Therefore, a novel waveguide structure and a design method thereof are needed in the art, which can realize the self-emission and stable frequency selection function with specific frequency as a threshold value under the condition of not depending on an external switch or a control circuit, thereby simplifying the system architecture, improving the working reliability and expanding the application potential of the waveguide in a frequency self-adaptive system. Disclosure of Invention The invention provides a rectangular waveguide based on electromagnetic kerr metamaterials and a design method thereof, wherein a self-driven frequency selection waveguide taking tunable kerr frequency as a threshold value is constructed by adjusting the structural parameters of saddle-shaped metal units with D 2d point group symmetry, so that the technical problems of complex system structure, insufficient regulation and control flexibility and poor autonomy caused by the fact that the traditional waveguide depends on an external filter or a switching element to realize a frequency selection function are solved. According to one aspect of the invention, a design method of a rectangular waveguide based on electromagnetic metamaterial is provided, which comprises the following steps of S100, constructing a metamaterial waveguide, namely enabling the frequency of an external point to be matched with a target screening frequency by adjusting structural parameters of saddle-shaped metal units with D 2d point group symmetry, and periodically arranging saddle-shaped metal units with the structural parameters along a three-dimensional direction to form a rectangular waveguide nested structure so as to realize a self-driven frequency selection function, S200, performing waveguide simulation verification, namely performing metamaterial waveguide modeling by using CST full-wave simulation software, setting a limited period for the metamaterial waveguide along a transmission direction, adopting an x-y-z all-direction open boundary condition, simulating electromagnetic transmission characteristics of an actual waveguide, calculating electromagnetic field response of a main mode or electromagnetic field response of a waveguide fundamental mode, and further verifying the self-driven frequency selection function, and S300, analyzing the transmission characteristics of the metamaterial w