A non-contact artificial electromagnetic bandgap material and its miniaturization method and microwave circuit

Abstract

The present invention discloses a non-contact artificial electromagnetic bandgap material and a miniaturization method thereof and a microwave circuit, and relates to the field of microwave electronic circuits, and is used to realize the miniaturization of artificial electromagnetic bandgap materials. The present invention provides an insulating layer on the inner surface of a metal plate of an air gap non-contact artificial electromagnetic bandgap material, and can ensure that the electromagnetic bandgap still meets the design requirements when the size of the non-contact artificial electromagnetic bandgap material is reduced exponentially based on the relative dielectric constant of the insulating layer, thereby realizing the miniaturization of the material. The present invention overcomes the technical prejudice of needing to fill the entire air area with a dielectric, has low implementation difficulty, and does not require the redevelopment of the material structure.

Description

Technical Field

[0001] The invention relates to the technical field of microwave electronic circuits, in particular to a non-contact artificial electromagnetic bandgap material and a miniaturization method thereof and a microwave circuit. Background Art

[0002] Gap waveguide circuit technology is a non-contact waveguide transmission circuit technology that uses non-contact artificial electromagnetic bandgap materials as an electromagnetic shielding method. It has been widely used in gap waveguide antennas, gap waveguide non-contact flanges, gap waveguide passive and active circuit packaging, low passive intermodulation integration and other technical fields. Non-contact artificial electromagnetic bandgap materials are the core of gap waveguide circuit technology. The performance of non-contact artificial electromagnetic bandgap materials determines the performance of gap waveguide circuits.

[0003] Currently, the most widely used non-contact artificial electromagnetic bandgap materials include: 1) the full-height bed-of-nails type non-contact artificial electromagnetic bandgap materials proposed in the literature "Localmetamaterial-based waveguides in gaps between parallel metal plates" (PS.Kildal et al.); 2) the half-height bed-of-nails type non-contact artificial electromagnetic bandgap materials proposed in the literature "Bandwidth investigation on half-height pin in ridge gap waveguide" (F.Fan et al.); 3) the interdigitated non-contact artificial electromagnetic bandgap materials proposed in the Chinese patent literature with publication number CN110099556A; 4) the random complementary distribution type non-contact artificial electromagnetic bandgap materials; 5) the soft and hard surface type non-contact artificial electromagnetic bandgap materials proposed in the Chinese patent literature with publication number CN111988974A; 6) the cost-effective gap waveguide technologybased on glide-symmetric holey EBG 7) The non-contact artificial electromagnetic bandgap materials of the type with sliding symmetric holes are represented by the Chinese patent document with publication number CN113987607A. These non-contact artificial electromagnetic bandgap materials have a common feature, that is, the lattice period of the material is about half of the central wavelength of the electromagnetic bandgap, and the height of the bed of nails or the depth of the holes is about one-quarter of the central wavelength of the electromagnetic bandgap. This feature limits the application of non-contact artificial electromagnetic bandgap materials in the long wavelength frequency band, and will cause the size of the non-contact artificial electromagnetic bandgap materials to be too large and difficult to apply.

[0004] The currently known solution to the problem of non-contact electromagnetic bandgap materials being too large is the folded non-contact flange introduced in the document "A Folded Contactless Waveguide Flange for Low Passive-Intermodulation Applications" (Xiang Chen et al.), which solves the problem of the S-band non-contact waveguide flange being too large. However, while reducing the flange area, this solution increases the flange length and does not fundamentally solve the problem of miniaturization of material size. Summary of the invention

[0005] The object of the present invention is to provide a non-contact artificial electromagnetic bandgap material and a miniaturization method thereof and a microwave circuit to achieve the miniaturization of the artificial electromagnetic bandgap material in order to solve all or part of the above-mentioned problems.

[0006] The technical solution adopted by the present invention is as follows:

[0007] A non-contact artificial electromagnetic bandgap material, the crystal lattice of which comprises a first metal plate and a second metal plate arranged opposite to each other, and an insulating layer is arranged on the inner surface of the first metal plate and / or the second metal plate.

[0008] Furthermore, the insulating layer is arranged on the inner surface of the metal plate by a physical or chemical method.

[0009] Furthermore, the insulating layer is obtained by micro-arc oxidation, non-conductive oxidation surface treatment or physical spraying.

[0010] Furthermore, the insulating layer is sandwiched or bonded to the inner surface of the metal plate.

[0011] Furthermore, the type of the non-contact artificial electromagnetic bandgap material is one or more of a combination of a full-height bed of nails type, a half-height bed of nails type, an interdigitated type, a random complementary distribution of bed of nails type, a soft and hard surface type, a sliding symmetrical hole type or a firewood pile type.

[0012] Furthermore, the insulating layer covers all or part of the inner surface of the metal plate.

[0013] The present invention also provides a method for miniaturizing the non-contact artificial electromagnetic bandgap material, which comprises the following process:

[0014] Establish a simulation model of a target type of air gap non-contact artificial electromagnetic bandgap material, and optimize the electromagnetic bandgap of the simulation model of the air gap non-contact artificial electromagnetic bandgap material to meet the design goal;

[0015] Using insulating materials to replace air gaps, a simulation model of dielectric gap non-contact artificial electromagnetic bandgap materials is established;

[0016] Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is reduced according to the dielectric constant of the insulating material;

[0017] Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is miniaturized and optimized until the target size is met.

[0018] Furthermore, by adjusting one or more of the thickness of the air gap, the lattice period, the height of the bed of nails or the hole depth in the air gap non-contact artificial electromagnetic bandgap material, the electromagnetic bandgap of the air gap non-contact artificial electromagnetic bandgap material simulation model is optimized.

[0019] Furthermore, the miniaturization optimization of the size of the dielectric gap non-contact artificial electromagnetic bandgap material simulation model includes:

[0020] Increase the nail bed height or hole depth to reduce the lattice period; or,

[0021] Increase the lattice period and reduce the nail bed height or hole depth.

[0022] The present invention also provides a microwave circuit using the non-contact artificial electromagnetic bandgap material.

[0023] In summary, due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0024] The present invention breaks the theoretical constraint that the entire air area needs to be filled with dielectrics to achieve the miniaturization of non-contact artificial electromagnetic bandgap materials under the guidance of the theory of ideal electric conductor surface-ideal magnetic conductor surface, and creatively proposes the theory of periodic high and low impedance region coherent scattering of ready-made electromagnetic bandgap, and proposes a technical solution that can achieve the miniaturization of electromagnetic bandgap materials by only filling the low impedance region. The thickness of the low impedance region is very thin, and only a thin dielectric insulating layer needs to be prepared on the surface of the traditional material by physical or chemical methods. The implementation difficulty of this method is extremely low and the cost is low compared to the full area filling. In addition, the miniaturization method of the present invention is applicable to all currently known materials, and there is no need to redevelop the structure of artificial electromagnetic bandgap materials. It only needs to reduce the size of the existing electromagnetic bandgap materials to achieve the same electromagnetic bandgap coverage. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The present invention will now be described by way of example with reference to the accompanying drawings, in which:

[0026] Figure 11 is a structural diagram of four types of non-contact artificial electromagnetic bandgap material lattices in the embodiments of the present application, wherein (a) is a full-height bed of nails type, (b) is a soft and hard surface type, (c) is a half-height bed of nails type, and (d) is a sliding symmetric hole type.

[0027] Figure 2 It is a flow chart of the method for miniaturizing non-contact artificial electromagnetic bandgap materials in an embodiment of the present application.

[0028] Figure 3 and Figure 4 They are Figure 1 (a) A simulated dispersion curve diagram of a non-contact artificial electromagnetic bandgap material of the type using an air gap and a dielectric gap; Figure 3 (a) is a simulation diagram of the electromagnetic bandgap of a full-height nail bed type non-contact artificial electromagnetic bandgap material with air gap. Figure 3 (b) is a simulation diagram of the electromagnetic bandgap of a full-height bed-of-nails type artificial electromagnetic bandgap material with a dielectric gap; Figure 4 (a) is the electromagnetic bandgap simulation and size diagram of the air gap full-height nail bed type non-contact artificial electromagnetic bandgap material. Figure 4 (b) is to obtain Figure 4 (a) Electromagnetic bandgap simulation and size diagram of the full-height bed-of-nails type artificial electromagnetic bandgap material with a dielectric gap when the electromagnetic bandgap is approximated.

[0029] Figure 5 and Figure 6 They are Figure 1 (b) a simulated dispersion curve diagram of the non-contact artificial electromagnetic bandgap material of the type using an air gap and a dielectric gap; Figure 5 (a) is the electromagnetic bandgap simulation diagram of the air gap soft and hard surface type non-contact artificial electromagnetic bandgap material. Figure 5 (b) is a simulation diagram of the electromagnetic bandgap of the dielectric gap soft and hard surface type artificial electromagnetic bandgap material; Figure 6 (a) is the electromagnetic bandgap simulation and size diagram of the air gap soft and hard surface non-contact artificial electromagnetic bandgap material. Figure 6 (b) is to obtain Figure 6 (a) Electromagnetic bandgap simulation and size diagram of artificial electromagnetic bandgap materials with soft and hard surfaces in dielectric gaps when the electromagnetic bandgap is approximate.

[0030] Figure 7 and Figure 8 They are Figure 1 (c) A simulated dispersion curve diagram of an embodiment of a non-contact artificial electromagnetic bandgap material using an air gap and a dielectric gap; Figure 7 (a) is a simulation diagram of the electromagnetic bandgap of an air gap half-height bed of nails type non-contact artificial electromagnetic bandgap material. Figure 7(b) is a simulation diagram of the electromagnetic bandgap of a dielectric gap half-height bed of nails type artificial electromagnetic bandgap material; Figure 8 (a) is the electromagnetic bandgap simulation and size diagram of the air gap half-height bed of nails type non-contact artificial electromagnetic bandgap material. Figure 8 (b) is to obtain Figure 8 (a) Electromagnetic bandgap simulation and size diagram of the dielectric gap half-height bed of nails type artificial electromagnetic bandgap material when the electromagnetic bandgap is approximate.

[0031] Fig. 9 yes Figure 1 (d) a simulated dispersion curve diagram of an embodiment of a non-contact artificial electromagnetic bandgap material using an air gap and a dielectric gap; Fig. 9 (a) Simulation diagram of electromagnetic bandgap of air-gap sliding symmetric hole-type non-contact artificial electromagnetic bandgap material. Fig. 9 (b) is a simulation diagram of the electromagnetic bandgap of a dielectric gap sliding symmetric hole-type artificial electromagnetic bandgap material.

[0032] Fig.10 It is an S-parameter test diagram of microwave circuit simulation using three types of non-contact artificial electromagnetic bandgap materials.

[0033] In the figure, 1 is a first metal plate, 2 is a second metal plate, 3 is a first insulating layer, and 4 is a second insulating layer. DETAILED DESCRIPTION

[0034] All features disclosed in this specification, or steps in all methods or processes disclosed, except mutually exclusive features and / or steps, can be combined in any manner.

[0035] Any feature disclosed in this specification (including any additional claims and abstract), unless otherwise stated, may be replaced by other alternative features that are equivalent or have similar purposes. That is, unless otherwise stated, each feature is only an example of a series of equivalent or similar features.

[0036] In view of the problem that the lattice period of the existing air gap non-contact artificial electromagnetic bandgap material is approximately half of the central wavelength of the electromagnetic bandgap, the height or depth of the material is one-quarter of the central wavelength of the electromagnetic bandgap, and the application adaptability of the non-contact artificial electromagnetic bandgap material in the long wavelength frequency band is limited due to its large size, the embodiment of the present application proposes a non-contact artificial electromagnetic bandgap material, which aims to achieve the miniaturization of the non-contact artificial electromagnetic bandgap material through a simple design without redeveloping the material structure.

[0037] For this purpose, the embodiment of the present application proposes a non-contact artificial electromagnetic bandgap material, which includes a first metal plate 1 and a second metal plate 2 arranged opposite to each other, and an insulating layer is arranged on the inner surface of the first metal plate 1 and / or the second metal plate 2. The so-called inner surface of the metal plate is the surface facing the other metal plate, for the first metal plate 1, it is the surface facing the second metal plate 2, and for the second metal plate 2, it is the surface facing the first metal plate 1. That is, the insulating layer can be arranged on one of the two metal plates of the non-contact artificial electromagnetic bandgap material, or it can be arranged on both metal plates.

[0038] The design theory of the non-contact artificial electromagnetic bandgap material in the prior art is based on the ideal electric conductor surface and the ideal magnetic conductor surface, such as the principle introduced in the document "Three metamaterial-based gap waveguides between parallel metal plates for mm / submm waves" (PS.Kildal et al.). The electric field on the surface of an ideal electric conductor is perpendicular to the surface and the magnetic field is parallel to the surface, while the situation is exactly the opposite for the surface of an ideal magnetic conductor, that is, the electric field is parallel to the surface of the ideal magnetic conductor and the magnetic field is perpendicular to the surface of the ideal magnetic conductor. When the two surfaces are placed in parallel, an ideal electric conductor surface-ideal magnetic conductor surface boundary condition is formed. It is theoretically proved that this is a long wavelength suppression structure. Specifically, electromagnetic waves with a wavelength longer than 4 times the distance between the two surfaces cannot exist in this space, that is, the long wavelength is cut off, thus forming an electromagnetic bandgap. There is no ideal magnetic conductor surface in nature, so a periodically distributed bed of nails, ridges, grooves or holes are used to form an equivalent magnetic conductor surface, that is, an artificial magnetic conductor surface. To achieve the miniaturization of non-contact artificial electromagnetic bandgap materials, that is, to achieve the same electromagnetic bandgap, the size of the electromagnetic bandgap material should be smaller than the original size, which is equivalent to moving the electromagnetic bandgap of the non-contact artificial electromagnetic bandgap material to the long wavelength (low frequency band) direction while the material size remains unchanged. According to the theory of ideal electric conductor surface-ideal magnetic conductor surface, the key to achieving the shift of the electromagnetic bandgap to a long wavelength is to move the working wavelength of the artificial magnetic conductor surface to a long wavelength. Therefore, filling the inner area of ​​the artificial magnetic conductor surface with dielectric is an effective method, that is, filling the empty area outside the nail bed and ridges or the grooves and holes with dielectric.

[0039] It has been found through research that the working frequency band of the surface of the artificial magnetic conductor is relatively narrow, while the electromagnetic bandgap width of the non-contact artificial electromagnetic bandgap material formed by it exceeds the frequency width of the surface of the artificial magnetic conductor. Therefore, the traditional ideal electric conductor surface-ideal magnetic conductor surface theory has guiding significance in the qualitative analysis of the characteristics of the non-contact artificial electromagnetic bandgap, but it is insufficient in quantitative analysis. In view of the above problems, the present application proposes a periodically loaded transmission line theoretical model to analyze the electromagnetic bandgap of the non-contact artificial electromagnetic bandgap material. Specifically, the nail bed, ridges or holes form periodic protrusions or grooves between the two originally uniform metal planes. These protrusion areas or groove areas make the characteristic impedance of the area much lower or much higher than the surrounding area, that is, an impedance distribution with alternating high and low impedance is formed. When passing through these areas, electromagnetic waves are continuously scattered. Since the high and low impedance areas are periodic, the phases of these scattered waves have a stable phase difference. For certain wavelengths, these scattered waves form constructive interference, thus forming a passband. On the contrary, if these scattered waves form destructive interference, a bandgap is formed. According to the analysis, the main factors affecting the electromagnetic bandgap are the characteristic impedances of the high impedance zone and the low impedance zone. To change the range of the electromagnetic bandgap, the key is to change the impedance ratio of the high and low impedance zones. Therefore, in the traditional thinking, filling the dielectric in all areas will reduce the characteristic impedance of the high and low impedance zones at the same time, which is not conducive to the migration of the electromagnetic bandgap to the low frequency band. The present application abandons this technical prejudice, only loads insulating material in the low impedance zone where the distance between the two metal plates is close, and maintains the impedance of the high impedance zone unchanged. Only in the non-contact artificial electromagnetic bandgap material, an insulating layer is set on the inner surface of the metal plate to reduce the characteristic impedance of the low impedance zone. Under the same structural size, the electromagnetic bandgap is migrated to the long wavelength region, and the size of the non-contact artificial electromagnetic bandgap material is reduced to ensure that the electromagnetic bandgap meets the requirements, thereby realizing structural miniaturization. This method does not require the redevelopment of the structure of the non-contact artificial electromagnetic bandgap material, and the miniaturization design of various existing types of non-contact artificial electromagnetic bandgap materials can be achieved through simple operation.

[0040] In some embodiments, the insulating layer disposed on the inner surface of the metal plate is disposed on the inner surface of the metal plate by a physical or chemical method.

[0041] In some feasible embodiments, the method of providing the insulating layer on the metal plate includes but is not limited to performing micro-arc oxidation, non-conductive oxidation surface treatment and physical spraying of insulating materials on the inner surface of the metal plate to obtain the insulating layer. In other feasible embodiments, the insulating layer can also be provided on the inner surface of the metal plate by other physical methods, such as directly clamping or bonding the insulating layer to the inner surface of the metal plate to replace the traditional air gap.

[0042] In addition, the insulating layer is not required to cover the entire metal plate, and it may cover the entire or a portion of the inner surface of the metal plate.

[0043] The design concept of the embodiments of the present application is applicable to all types of non-contact artificial electromagnetic bandgap materials in the prior art, that is, the non-contact artificial electromagnetic bandgap material type of the embodiments of the present application is one or more combinations of full-height bed of nails type, half-height bed of nails type, interdigitated type, random complementary distribution of bed of nails type, soft and hard surface type, sliding symmetrical hole type or firewood pile type.

[0044] like Figure 1 The lattice structures of four different types of non-contact artificial electromagnetic bandgap materials proposed in the embodiments of this application are shown. Figure 1 As shown in (a), in some embodiments, the first metal plate 1 that does not contact the artificial electromagnetic bandgap material lattice is a smooth metal plate, the second metal plate 2 is a full-height nail bed metal plate, the first metal plate 1 is provided with a first insulating layer 3 on the inner surface, and the second metal plate 2 is provided with a second insulating layer 4 on the inner surface. Figure 1 As shown in (b), in other embodiments, the first metal plate 1 that does not contact the artificial electromagnetic bandgap material lattice is a hard surface metal plate, the second metal plate 2 is a soft surface metal plate, the first metal plate 1 is provided with a first insulating layer 3 on its inner surface, and the second metal plate 2 is provided with a second insulating layer 4 on its inner surface. Figure 1 As shown in (c), in other embodiments, the first metal plate 1 of the non-contact artificial electromagnetic bandgap material lattice is a half-height nail bed metal plate, the second metal plate 2 is also a half-height nail bed metal plate, the first metal plate 1 is provided with a first insulating layer 3 on the inner surface, and the second metal plate 2 is provided with a second insulating layer 4 on the inner surface. Figure 1 As shown in (d), in other embodiments, the first metal plate 1 that does not contact the artificial electromagnetic band gap material lattice is a hole metal plate, the second metal plate 2 is a second hole metal plate, the inner surface of the first metal plate 1 is provided with a first insulating layer 3, and the inner surface of the second metal plate 2 is provided with a second insulating layer 4.

[0045] exist Figure 1 In each embodiment, the lateral width and the longitudinal width of the non-contact artificial electromagnetic bandgap material lattice are , the height of the nail bed and the metal ridge on the first metal plate 1 and the second metal plate 2 is ; The width of the nail bed and the metal ridge on the first metal plate 1 and the second metal plate 2 is The radius and depth of the holes on the first metal plate 1 and the second metal plate 2 are and The thickness of the insulating layer is , the relative dielectric constant is .

[0046] Figure 1In the illustrated embodiment, an insulating layer is disposed on both the first metal plate 1 and the second metal plate 2 , but it should be understood that the insulating layer may also be disposed on only one of the metal plates.

[0047] like Figure 2 As shown, the embodiment of the present application also proposes a method for miniaturizing a non-contact artificial electromagnetic bandgap material, which includes the following process:

[0048] S1. Establish a simulation model of a target type of air gap non-contact artificial electromagnetic bandgap material, and optimize the electromagnetic bandgap of the simulation model of the air gap non-contact artificial electromagnetic bandgap material to meet the design objectives.

[0049] In some embodiments, step S1 includes the following sub-steps:

[0050] S1.1. Select the type of non-contact artificial electromagnetic bandgap material that needs to be miniaturized as needed. As described in the above embodiments, the selected type can be one of the full-height bed of nails type, half-height bed of nails type, interdigitated type, bed of nails randomly complementary distribution type, hard and soft surface type, sliding symmetric hole type or firewood pile type, or a combination of some or all of these types.

[0051] S1.2. According to the selected type, a simulation model of the air gap non-contact artificial electromagnetic bandgap material is established, and the initial value of the size of the air gap non-contact artificial electromagnetic bandgap material is set.

[0052] In some feasible embodiments, sub-step S1.2 sets the lattice period of the air gap non-contact artificial electromagnetic bandgap material to half of the target electromagnetic bandgap center wavelength, the nail bed height or hole depth (depending on the selected type) to one quarter of the target electromagnetic bandgap center wavelength, and the thickness of the air gap to one twentieth of the target electromagnetic bandgap center wavelength.

[0053] S1.3. Calculate and optimize the electromagnetic bandgap of the air gap non-contact artificial electromagnetic bandgap material simulation model.

[0054] In this sub-step S1.3, the electromagnetic bandgap of the air gap non-contact artificial electromagnetic bandgap material simulation model can be optimized by adjusting one or more of the thickness of the air gap, the lattice period, the nail bed height or the hole depth in the air gap non-contact artificial electromagnetic bandgap material.

[0055] In some feasible implementations, the execution process of sub-step S1.3 includes:

[0056] Calculate the electromagnetic bandgap of the air-gap non-contact artificial electromagnetic bandgap material under the initial size (i.e., the size when the simulation model is established). If the result meets the design target, stop the optimization process; if the electromagnetic bandgap width is too small, gradually reduce the thickness of the air gap until the electromagnetic bandgap meets the design target; if the electromagnetic bandgap width still does not meet the design target when the air gap thickness is reduced to zero, set the thickness of the air gap to the minimum thickness allowed, and then reduce one or more of the lattice period of the air-gap non-contact artificial electromagnetic bandgap material, the nail bed height or the hole depth until the electromagnetic bandgap width covers the design target. If the electromagnetic bandgap frequency coverage range is biased towards the low frequency band compared with the design target, then reduce one or more of the lattice period of the air gap non-contact artificial electromagnetic bandgap material, the nail bed height or the hole depth until the center frequency of the electromagnetic bandgap coincides with the target electromagnetic bandgap center frequency; if the electromagnetic bandgap frequency coverage range is biased towards the high frequency band compared with the design target, then increase one or more of the lattice period of the air gap non-contact artificial electromagnetic bandgap material, the nail bed height or the hole depth until the center frequency of the electromagnetic bandgap coincides with the target electromagnetic bandgap center frequency.

[0057] S2. Use insulating materials to replace the air gap and establish a simulation model of dielectric gap non-contact artificial electromagnetic band gap materials.

[0058] Insulating materials have a corresponding relative dielectric constant , and the relative dielectric constant of the insulating material The miniaturization ratio of the dielectric gap non-contact artificial electromagnetic band gap material can be determined.

[0059] In step S2, an insulating material is selected to replace the air gap according to the size to be miniaturized. The principle of selecting the insulating material is: the relative dielectric constant of the insulating layer The higher the value, the higher the miniaturization rate of the dielectric gap non-contact artificial electromagnetic bandgap material. The linear ratio of the dielectric gap non-contact artificial electromagnetic bandgap material to the air gap non-contact artificial electromagnetic bandgap material is approximately For example, if the lattice period, nail bed height or hole depth of the non-contact artificial electromagnetic bandgap material is reduced to one-third of the original size (i.e. before replacing the air gap), the relative dielectric constant of the replaced insulating material will be Should be greater than 9.

[0060] After replacing the air gap with insulating material, a simulation model of dielectric gap non-contact artificial electromagnetic band gap material can be established.

[0061] S3. Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is reduced according to the dielectric constant of the insulating material.

[0062] After replacing the air gap with the dielectric gap, the lattice period, the nail bed height or the hole depth, and the thickness of the dielectric gap of the obtained dielectric gap non-contact artificial electromagnetic band gap material simulation model are reduced to the values ​​before replacing the air gap. .

[0063] After initially reducing the size of the non-contact artificial electromagnetic bandgap material, the electromagnetic bandgap of the dielectric gap non-contact artificial electromagnetic bandgap material simulation model is calculated and optimized. If the electromagnetic bandgap range covers the design target, the miniaturization design is completed. Otherwise, the electromagnetic bandgap of the dielectric gap non-contact artificial electromagnetic bandgap material simulation model needs to be optimized. This process can refer to the method of the above sub-step S1.3, the only difference is that sub-step S1.3 is for air gaps, while this is for dielectric gaps. Therefore, the specific optimization process is not repeated here.

[0064] S4. Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is miniaturized and optimized until the target size is met.

[0065] In step S3, the size of the non-contact artificial electromagnetic bandgap material is reduced, but it may not meet the miniaturization requirements. Here, after the initial size reduction, step S4 further optimizes the size of the non-contact artificial electromagnetic bandgap material in a targeted manner.

[0066] In some embodiments, the process of miniaturizing and optimizing the size of the non-contact artificial electromagnetic bandgap material in step S4 includes:

[0067] Increase the nail bed height or hole depth to reduce the lattice period; or,

[0068] Increase the lattice period and reduce the nail bed height or hole depth.

[0069] In the specific implementation, the size requirements for the non-contact artificial electromagnetic bandgap material may not necessarily be required in both the lattice period and the nail bed height (or hole depth). For example, in some miniaturized embodiments, only the miniaturization of the lattice period of the non-contact artificial electromagnetic bandgap material is concerned, and the miniaturization of the height dimension (i.e., the nail bed height or the hole depth) is not concerned. For this requirement, the nail bed height or the hole depth can be increased to the maximum acceptable height or maximum depth, and then the lattice period of the non-contact artificial electromagnetic bandgap material can be further reduced. The process of increasing the nail bed height or the hole depth and reducing the lattice period needs to ensure that the electromagnetic bandgap meets the design goals. This can be optimized by re-adopting the method of optimizing the electromagnetic bandgap in sub-step S1.3, that is, by adjusting one or more of the thickness of the air gap, the lattice period, the nail bed height or the hole depth in the dielectric gap non-contact artificial electromagnetic bandgap material, the electromagnetic bandgap of the dielectric gap non-contact artificial electromagnetic bandgap material simulation model is optimized. On the contrary, some miniaturization embodiments only care about the miniaturization of the height dimension of the non-contact artificial electromagnetic bandgap material, and do not care about the miniaturization of the lattice period. To meet this demand, the lattice period is increased and the nail bed height or the hole depth is reduced. This process also needs to ensure that the electromagnetic bandgap meets the design goals, and can also be optimized by using the method of optimizing the electromagnetic bandgap in sub-step S1.3.

[0070] In addition, if step S4 still cannot meet the design requirements for the size of the non-contact artificial electromagnetic bandgap material, the relative dielectric constant of the insulating material is increased. , re-execute the above steps S2 to S4 until the size of the non-contact artificial electromagnetic bandgap material reaches the design requirements.

[0071] The embodiments of the present application also verify the performance of the proposed non-contact artificial electromagnetic bandgap material.

[0072] by Figure 1 The full-height nail bed type non-contact artificial electromagnetic bandgap material of (a) structure is taken as an example, and the relative dielectric constant of its insulating layer is set to 9. In other aspects, , , , .like Figure 3 The figure shows the simulated electromagnetic bandgap of the same size full-height bed-of-nails type non-contact artificial electromagnetic bandgap material before and after miniaturization. Figure 3 (a) is the simulated electromagnetic bandgap of the air gap full-height bed-of-nails type non-contact artificial electromagnetic bandgap material before miniaturization. Figure 3 (b) is the simulated electromagnetic bandgap of the full-height bed of nails type artificial electromagnetic bandgap material after setting a dielectric insulating layer with a relative dielectric constant of 9.

[0073] Figure 3The embodiment provides a simulation comparison of electromagnetic bandgap of full-height bed-of-nails type non-contact artificial electromagnetic bandgap materials with air gap and dielectric gap of the same size. The present application also continues to compare the size of non-contact artificial electromagnetic bandgap materials with similar electromagnetic bandgap. Figure 4 The figure shows the simulated electromagnetic bandgap and its size of the full-height nail bed type air gap non-contact artificial electromagnetic bandgap material under the approximate electromagnetic bandgap ( Figure 4 (a)) and the simulated electromagnetic bandgap and its size of miniaturized full-height bed-of-nails dielectric gap artificial electromagnetic bandgap materials ( Figure 4 (b) Comparison diagram of . Figure 4 In the embodiment, the relative dielectric constant of the insulating layer is still maintained at 9. In other aspects, for the air gap non-contact artificial electromagnetic bandgap material, , , , , for dielectric gap artificial electromagnetic bandgap materials, , , , .Depend on Figure 4 It can be seen that when the approximate electromagnetic bandgap is achieved, the dielectric gap non-contact artificial electromagnetic bandgap material with an added insulating layer is reduced to 1 / 3 of the air gap non-contact artificial electromagnetic bandgap material in terms of size, nail bed height and width, and gap thickness.

[0074] by Figure 1 The (b) structure of the hard-soft surface type non-contact artificial electromagnetic bandgap material is taken as an example, and the relative dielectric constant of the insulating layer is set to 9. In other aspects, , , , .like Figure 5 The figure shows the simulated electromagnetic bandgap of the same size hard-soft surface non-contact artificial electromagnetic bandgap material before and after miniaturization. Figure 5 (a) is the simulated electromagnetic bandgap of the air gap hard-soft surface non-contact artificial electromagnetic bandgap material before miniaturization. Figure 5 (b) is the simulated electromagnetic bandgap of the hard-soft surface type artificial electromagnetic bandgap material after setting a dielectric insulating layer with a relative dielectric constant of 9.

[0075] Figure 5 The embodiment provides a simulation comparison of electromagnetic bandgap of hard-soft surface type non-contact artificial electromagnetic bandgap materials with air gap and dielectric gap of the same size. The present application also continues to compare the size of non-contact artificial electromagnetic bandgap materials with similar electromagnetic bandgap. Figure 6 The figure shows the simulated electromagnetic bandgap and its size of the hard-soft surface type air gap non-contact artificial electromagnetic bandgap material under the approximate electromagnetic bandgap. Figure 6(a)) and the simulated electromagnetic bandgap and its size of miniaturized hard-soft surface dielectric gap artificial electromagnetic bandgap materials ( Figure 6 (b) Comparison diagram of . Figure 6 In the embodiment, the relative dielectric constant of the insulating layer is still maintained at 9. In other aspects, for the air gap non-contact artificial electromagnetic bandgap material, , , , , for dielectric gap artificial electromagnetic bandgap materials, , , , .Depend on Figure 6 It can be seen that when the approximate electromagnetic bandgap is achieved, the dielectric gap non-contact artificial electromagnetic bandgap material with an added insulating layer is reduced to 1 / 3 of the air gap non-contact artificial electromagnetic bandgap material in size, nail bed (or ridge) height and width, and gap thickness.

[0076] by Figure 1 Taking the half-height nail bed type non-contact artificial electromagnetic bandgap material of structure (c) as an example, the relative dielectric constant of its insulating layer is set to 9. In other aspects, , , , .like Figure 7 The figure shows the simulated electromagnetic bandgap of the same size half-height bed-of-nails type non-contact artificial electromagnetic bandgap material before and after miniaturization. Figure 7 (a) is the simulated electromagnetic bandgap of the air gap half-height bed of nails type non-contact artificial electromagnetic bandgap material before miniaturization. Figure 7 (b) is the simulated electromagnetic bandgap of a half-height bed of nails type artificial electromagnetic bandgap material after setting a dielectric insulating layer with a relative dielectric constant of 9.

[0077] Figure 7 The embodiment provides a simulation comparison of electromagnetic bandgap of half-height bed of nails type non-contact artificial electromagnetic bandgap materials with air gap and dielectric gap of the same size. The present application also continues to compare the size of non-contact artificial electromagnetic bandgap materials with similar electromagnetic bandgap. Figure 8 The figure shows the simulated electromagnetic bandgap and its size of the half-height bed of nails type air gap non-contact artificial electromagnetic bandgap material under the approximate electromagnetic bandgap ( Figure 8 (a)) and the simulated electromagnetic bandgap and its size of the miniaturized half-height bed-of-nails dielectric gap artificial electromagnetic bandgap material ( Figure 8 (b) Comparison diagram of . Figure 8 In the embodiment, the relative dielectric constant of the insulating layer is still maintained at 9. In other aspects, for the air gap non-contact artificial electromagnetic bandgap material, , , , , for dielectric gap artificial electromagnetic bandgap materials, , , , .Depend on Figure 8 It can be seen that when the approximate electromagnetic bandgap is achieved, the dielectric gap non-contact artificial electromagnetic bandgap material with an added insulating layer is reduced to 1 / 3 of the air gap non-contact artificial electromagnetic bandgap material in terms of size, nail bed height and width, and gap thickness.

[0078] by Figure 1 The sliding symmetric hole-type non-contact artificial electromagnetic bandgap material of the structure (d) is taken as an example, and the relative dielectric constant of its insulating layer is set to 9. In other aspects, , , , .like Fig. 9 The figure shows the simulated electromagnetic bandgap of the same size half-height bed-of-nails type non-contact artificial electromagnetic bandgap material before and after miniaturization. Fig. 9 (a) is the simulated electromagnetic bandgap of the air-gap sliding symmetric hole-type non-contact artificial electromagnetic bandgap material before miniaturization. Fig. 9 (b) is the simulated electromagnetic bandgap of the sliding symmetric hole-type non-contact artificial electromagnetic bandgap material after setting a dielectric insulating layer with a relative dielectric constant of 9. Figure 3 , Figure 5 , Figure 7 and Fig. 9 It can be seen that under the same structural size, the electromagnetic bandgap of the dielectric gap non-contact artificial electromagnetic bandgap material has shifted to the long wavelength region.

[0079] The present application is based on the new electromagnetic bandgap theoretical analysis, breaking the traditional technical prejudice that the miniaturization of non-contact artificial electromagnetic bandgap materials requires dielectric filling of all the gaps inside the non-contact artificial electromagnetic bandgap materials. A method for miniaturization of the structure can be creatively proposed by only filling the low impedance area with dielectric. The low impedance area is an area where the distance between two metal plates is relatively close, usually with a spacing of 10 microns to 1 mm. The required insulating layer can be achieved by forming a layer of insulating film of such thickness on the surface of the metal plate by physical or chemical methods, and the bonding force is good, not easy to fall off, and it also has a certain anti-corrosion ability. When the relative dielectric constant of the insulating layer reaches 9, under the same structural size, the electromagnetic bandgap center frequency of the non-contact artificial electromagnetic bandgap material with an insulating layer is about one-third of the traditional structure, so that its size can be reduced to about one-third of the traditional structure, effectively realizing the structural miniaturization of the non-contact artificial electromagnetic bandgap material. This miniaturization method is effective for all currently known non-contact artificial electromagnetic bandgap materials. Therefore, this miniaturization method does not require targeted material structure redevelopment, and only requires one more surface treatment process after the processing is completed.

[0080] The present application also proposes a microwave circuit using the non-contact artificial electromagnetic bandgap material in the above embodiment. In some embodiments, the non-contact artificial electromagnetic bandgap material uses aluminum as a substrate (metal plate), and a micro-arc oxidation surface treatment process is used to prepare an insulating layer.

[0081] Microwave circuits can use miniaturized full-height bed of nails type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures, and the flange surface also uses miniaturized full-height bed of nails type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures; microwave circuits can also use miniaturized hard-soft surface type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures, and the flange surface uses miniaturized full-height bed of nails type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures; microwave circuits can also use miniaturized half-height bed of nails type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures, and the flange surface uses miniaturized full-height bed of nails type non-contact artificial electromagnetic bandgap materials as electromagnetic shielding structures. The size parameters of the non-contact artificial electromagnetic bandgap material lattices used in various structures are: , , In addition, in the full-height nail bed type non-contact artificial electromagnetic bandgap material, ; In the hard-soft surface type and half-high bed of nails type non-contact artificial electromagnetic bandgap materials, The microwave circuit is a standard WR75 rectangular waveguide with an internal size of 19.05 mm × 9.52 mm. Fig.10The figure shows the S parameter test diagram of the microwave circuit using three types of non-contact artificial electromagnetic bandgap materials. The results show that the insertion loss of the microwave circuit using three types of non-contact artificial electromagnetic bandgap materials is less than 0.05dB in the full frequency band of the waveguide, and the return loss is less than 25dB, which has excellent electromagnetic transmission performance.

[0082] The above embodiments propose miniaturized non-contact artificial electromagnetic bandgap materials and methods for miniaturizing non-contact artificial electromagnetic bandgap materials. On this basis, the embodiments of the present application also propose some applications of miniaturized non-contact artificial electromagnetic bandgap materials, such as microwave circuits using the non-contact artificial electromagnetic bandgap materials in the above embodiments, or the application of non-contact artificial electromagnetic bandgap materials in other microwave electronic circuits.

[0083] The present invention is not limited to the above-mentioned specific embodiments, but extends to any new features or any new combination disclosed in this specification, as well as any new method or process steps or any new combination disclosed.

Claims

1. A non-contact artificial electromagnetic bandgap material, wherein the lattice comprises a first metal plate (1) and a second metal plate (2) arranged opposite to each other, characterized in that: The type of the non-contact artificial electromagnetic bandgap material is one or more of a full-height bed of nails type, a half-height bed of nails type, an interdigitated type, a bed of nails randomly complementary distribution type, a soft-hard surface type, a sliding symmetrical hole type or a firewood pile type; an insulating layer is provided on the inner surface of the first metal plate (1) and / or the second metal plate (2), so that the insulating material is loaded in the low-impedance area between the two metal plates to reduce the characteristic impedance of the low-impedance area while maintaining the impedance of the high-impedance area unchanged, and the thickness of the insulating layer is much smaller than the height of the bed of nails or the metal ridges on the first metal plate (1) and the second metal plate (2).

2. The non-contact artificial electromagnetic bandgap material according to claim 1, characterized in that: The insulating layer is arranged on the inner surface of the metal plate by a physical or chemical method.

3. The non-contact artificial electromagnetic bandgap material according to claim 2, characterized in that: The insulating layer is prepared by micro-arc oxidation, non-conductive oxidation surface treatment or physical spraying.

4. The non-contact artificial electromagnetic bandgap material according to claim 2, characterized in that: The insulating layer is sandwiched or bonded to the inner surface of the metal plate.

5. The non-contact artificial electromagnetic bandgap material according to claim 1, characterized in that: The insulating layer covers the entire or a portion of the inner surface of the metal plate.

6. A method for miniaturizing a non-contact artificial electromagnetic bandgap material according to any one of claims 1 to 5, characterized in that: The following processes are included: Establish a simulation model of a target type of air gap non-contact artificial electromagnetic bandgap material, and optimize the electromagnetic bandgap of the simulation model of the air gap non-contact artificial electromagnetic bandgap material to meet the design goal; Using insulating materials to replace air gaps, a simulation model of dielectric gap non-contact artificial electromagnetic bandgap materials is established; Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is reduced according to the dielectric constant of the insulating material; Under the premise of ensuring that the electromagnetic bandgap meets the design objectives, the size of the simulation model of the dielectric gap non-contact artificial electromagnetic bandgap material is miniaturized and optimized until the target size is met.

7. The method for miniaturizing a non-contact artificial electromagnetic bandgap material according to claim 6, characterized in that: By adjusting one or more of the thickness of the air gap, the lattice period, the height of the nail bed or the hole depth in the air gap non-contact artificial electromagnetic bandgap material, the electromagnetic bandgap of the air gap non-contact artificial electromagnetic bandgap material simulation model is optimized.

8. The method for miniaturizing a non-contact artificial electromagnetic bandgap material according to claim 6, characterized in that: The miniaturization optimization of the size of the dielectric gap non-contact artificial electromagnetic bandgap material simulation model includes: Increase the nail bed height or hole depth to reduce the lattice period; or, Increase the lattice period and reduce the nail bed height or hole depth.

9. A microwave circuit using the non-contact artificial electromagnetic bandgap material as claimed in any one of claims 1 to 5.

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