A broadband absorption and penetration integrated frequency selective surface

Abstract

The present invention relates to a broadband absorption-transmission integrated frequency-selective surface, comprising: a first lossy layer for broadband transmission of mid- and high-frequency waves and absorption of low-frequency waves, the first lossy layer comprising m×n first units arranged in an array; a first foam substrate positioned below the first lossy layer; a second lossy layer positioned below the first foam substrate for transmission of mid-frequency waves and absorption of high-frequency waves, the second lossy layer comprising m×n second units arranged in an array; a second foam substrate positioned below the second lossy layer; and a bandpass frequency-selective layer positioned below the second foam substrate for broadband transmission of mid-frequency waves and providing a floor for absorption of low- and high-frequency waves, the bandpass frequency-selective layer comprising m×n third units arranged in an array. The broadband absorption-transmission integrated frequency-selective surface of the present invention achieves both broadband absorption and low-insertion-loss response across a wide transmission band.

Description

Technical Field

[0001] The present invention relates to the technical field of antenna stealth, and in particular to a broadband absorption-penetration integrated frequency-selective surface. Background Art

[0002] With the development of modern radar technology, equipment is required to achieve broadband stealth and reduce dual-station RCS (Radar Cross Section). A key focus of equipment stealth is the stealth of the antenna. Traditional antenna stealth relies on a frequency-selective radome, which can scatter radar waves in other directions based on its shape, achieving stealth by reducing the single-station RCS. However, this type of radome causes a surge in the dual-station RCS in specific directions, which cannot meet the stealth requirements of modern equipment. Therefore, in order to simultaneously reduce both single-station and dual-station RCS, researchers have proposed an absorptive frequency selective surface radome (AFSS), which is both absorbing and transparent. It can achieve low-loss transmission within the passband and absorb waves outside the passband, reducing the RCS by converting the energy of electromagnetic waves into heat.

[0003] The current wide-band absorption and penetration integrated frequency selection surface adopts a wide-band absorption and penetration frequency selection based on an open resonant ring loaded with a square resistance film. It consists of two layers of open resonant rings of different sizes and a bottom layer of bandpass frequency selection, which respectively realize the absorption bands at low and high frequencies. At the medium frequency, the two-layer structural units do not resonate, allowing electromagnetic waves to pass through the two layers to form a wave-transmitting band.

[0004] However, because the two layers of the aforementioned structure's transparent bands are undesigned, they naturally exhibit a certain amount of insertion loss. This cumulative loss of electromagnetic waves passing through these two layers ultimately results in high insertion loss in the transparent band. Conventional designs for wide-band, integrated frequency-selective absorption and transmission surfaces suffer from high insertion loss (2dB) within the transparent band. Summary of the Invention

[0005] In order to solve the above problems existing in the prior art, the present invention provides a broadband absorption and penetration integrated frequency selective surface. The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0006] One embodiment of the present invention provides a broadband absorption and penetration integrated frequency-selective surface, the broadband absorption and penetration integrated frequency-selective surface comprising:

[0007] A first lossy layer, configured to transmit broadband waves in the mid- and high-frequency parts and absorb waves in the low-frequency part, the first lossy layer comprising m×n first units arranged in an array;

[0008] a first foam substrate, located below the first lossy layer;

[0009] A second lossy layer, located below the first foam substrate, is used for transmitting waves in the intermediate frequency portion and absorbing waves in the high frequency portion, the second lossy layer comprising m×n second units arranged in an array;

[0010] a second foam substrate, located below the second lossy layer;

[0011] The bandpass frequency selection layer is located under the second foam substrate and is used for broadband wave transmission of intermediate frequencies and providing a floor for low-frequency and high-frequency wave absorption. The bandpass frequency selection layer includes m×n third units arranged in an array.

[0012] In one embodiment of the present invention, each of the first units includes a first square dielectric plate, four wound inductors, four capacitor strips, eight capacitor through-holes, and a first graphene square resistor, wherein:

[0013] The four winding inductors are embedded in the first square dielectric plate, and the four capacitor strips and the first graphene square resistor are located on a side of the first square dielectric plate away from the first foam substrate;

[0014] The four capacitor strips are arranged corresponding to the four sides of the first graphene square resistor, and capacitor through holes penetrating the first square dielectric plate are provided at both ends of each capacitor strip;

[0015] One end of each of the winding inductors is connected to one side of the first graphene square resistor, and the other end is connected to the capacitor strip through a via.

[0016] In one embodiment of the present invention, the thickness of the first square dielectric plate is in the range of 0.3-0.5 mm, and the relative dielectric constant is in the range of 3-4.

[0017] In one embodiment of the present invention, each of the second units includes a second square dielectric plate, four planar spiral inductors, four metal strips, four metalized vias, and a second graphene square resistor, wherein:

[0018] The four planar spiral inductors are located on a side of the second square dielectric plate close to the first foam substrate, and the four metal strips and the second graphene square resistor are located on a side of the second square dielectric plate close to the second foam substrate;

[0019] One end of the four metal strips is connected to the four sides of the second graphene square resistor respectively, and the other end is connected to the four planar spiral inductors respectively through the metallized vias;

[0020] Furthermore, two adjacent second units are connected via the planar spiral inductor.

[0021] In one embodiment of the present invention, the thickness of the second square dielectric plate is in the range of 0.1-0.3 mm, and the relative dielectric constant is in the range of 1.7-2.5.

[0022] In one embodiment of the present invention, the third unit includes:

[0023] a third square dielectric plate;

[0024] a fourth square dielectric plate, located below the third square dielectric plate;

[0025] Twelve square metal patches, four of which are distributed on a side of the third square dielectric plate away from the fourth square dielectric plate, four of which are distributed on a side of the fourth square dielectric plate close to the third square dielectric plate, and four of which are distributed on a side of the fourth square dielectric plate away from the third square dielectric plate;

[0026] The annular gap metal patch is located between the third square dielectric plate and the fourth square dielectric plate and has four annular gaps distributed in an array and passing through the annular gap metal patch.

[0027] In one embodiment of the present invention, the thickness of the third square dielectric plate and the fourth square dielectric plate are both in the range of 2.5-3 mm, and the relative dielectric constant is both in the range of 2-4.

[0028] In one embodiment of the present invention, the thickness of the first foam substrate is in the range of 11-13 mm, and the relative dielectric constant is in the range of 1-1.2.

[0029] In one embodiment of the present invention, the thickness of the second foam substrate is in the range of 6-8 mm, and the relative dielectric constant is in the range of 1-1.2.

[0030] Compared with the prior art, the present invention has the following beneficial effects:

[0031] The broadband absorption and penetration integrated frequency selection surface of the present invention is provided with a first loss layer, a second loss layer and a bandpass frequency selection layer in sequence from top to bottom. The first loss layer transmits broadband waves of the mid- and high-frequency parts and absorbs waves of the low-frequency part, the second loss layer transmits waves of the mid-frequency part and absorbs waves of the high-frequency part, and the bandpass frequency selection layer transmits broadband waves of the mid-frequency part and provides a floor for absorbing waves of the low and high frequencies. Therefore, a low insertion loss response of a wide wave transmission band is achieved while achieving a broadband absorption and penetration response.

[0032] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 This is a schematic structural diagram of a broadband absorption-through integrated frequency-selective surface provided by an embodiment of the present invention;

[0034] Figure 2 is a structural diagram of a first unit provided by an embodiment of the present invention;

[0035] Figure 3 is a structural diagram of a second unit provided by an embodiment of the present invention;

[0036] Figure 4 is a structural diagram of a third unit provided by an embodiment of the present invention;

[0037] Figure 5 It is a schematic diagram of the simulation results of the transmission curve (S21) and reflection curve (S11) of the absorption frequency selection and the absorption rate curve under the condition of vertical incidence;

[0038] Figure 6a and Figure 6b Schematic diagrams of the S-parameter curves obtained under TE polarization and TM polarization, respectively.

[0039] Explanation of symbols: first lossy layer-1; second lossy layer-2; bandpass frequency selection layer-3; first foam substrate-4; second foam substrate-5; first square dielectric plate-6; wound inductor-7; capacitor strip-8; capacitor through-hole-9; first graphene square resistor-10; second square dielectric plate-11; planar spiral inductor-12; metal strip-13; metalized via-14; second graphene square resistor-15; third square dielectric plate-16; fourth square dielectric plate-17; square metal patch-18. DETAILED DESCRIPTION

[0040] The present invention will be further described in detail below with reference to specific examples, but the embodiments of the present invention are not limited thereto.

[0041] It should be noted that the "up", "down", "left" and "right" mentioned in this embodiment are the positional relationships of the wide-band absorbent integrated frequency-selective surface when it is in the illustrated state, "length" is the lateral dimension of the wide-band absorbent integrated frequency-selective surface when it is in the illustrated state, and "thickness" is the longitudinal dimension of the wide-band absorbent integrated frequency-selective surface when it is in the illustrated state.

[0042] At present, the emerging radar communication technology has put forward higher requirements on the transmission bandwidth and absorption bandwidth of the integrated absorption and penetration frequency selective surface. Therefore, how to achieve a low insertion loss response in a wide transmission band while achieving a broadband absorption and penetration response has become an urgent problem to be solved. Based on this, the present invention proposes a broadband absorption and penetration integrated frequency selective surface, see Figure 1 , Figure 1This is a structural diagram of a broadband absorption and penetration integrated frequency-selective surface provided by an embodiment of the present invention. The present invention proposes that the broadband absorption and penetration integrated frequency-selective surface proposed by the present invention includes:

[0043] A first lossy layer 1 is used for broadband wave transmission in the mid- and high-frequency parts and wave absorption in the low-frequency part. The first lossy layer includes m×n first units arranged in an array;

[0044] A first foam substrate 4, located below the first lossy layer 1;

[0045] The second lossy layer 2 is located under the first foam substrate 4 and is used for transmitting the mid-frequency part and absorbing the high-frequency part. The second lossy layer 2 includes m×n second units arranged in an array;

[0046] A second foam substrate 5, located below the second lossy layer 2;

[0047] The bandpass frequency selection layer 3 is located under the second foam substrate 5 and is used for broadband wave transmission of intermediate frequencies and providing a floor for absorbing low and high frequencies. The bandpass frequency selection layer 3 includes m×n third units arranged in an array.

[0048] Specifically, the wide-band absorption and penetration integrated frequency-selective surface of the embodiment of the present invention is provided with a first loss layer, a second loss layer and a bandpass frequency-selective layer in sequence from top to bottom, and the first loss layer is used to transmit broadband waves of the medium and high frequency parts and absorb waves of the low frequency part, the second loss layer is used to transmit waves of the medium frequency part and absorb waves of the high frequency part, and the bandpass frequency-selective layer is used to transmit broadband waves of the medium frequency and provide a floor for absorbing waves of the low and high frequencies. Therefore, the wide-band absorption and penetration integrated frequency-selective surface of the embodiment of the present invention broadens the absorption and penetration frequency-selective absorbing band and realizes a low insertion loss and wide transmission band, and can effectively reduce the radar wave scattering cross-section of the antenna and can adapt to the use of ultra-wideband antennas.

[0049] It should be noted that the low frequency described in the embodiment of the present invention is 6.67-1.8 times the center wavelength, the medium frequency is 1.42-0.8 times the center wavelength, and the high frequency is 0.735-0.56 times the center wavelength.

[0050] In an optional embodiment, the thickness h2 of the first foam substrate 4 is in the range of 11-13 mm, and the relative dielectric constant is in the range of 1-1.2.

[0051] In an optional embodiment, the thickness h4 of the second foam substrate 5 is in the range of 6-8 mm, and the relative dielectric constant is in the range of 1-1.2.

[0052] In an optional embodiment, the first lossy layer includes m×n first units arranged in an array, m≥2, n≥2, see Figure 2Each of the first units includes a first square dielectric plate 6, four winding inductors 7, four capacitor strips 8, eight capacitor through-holes 9 and a first graphene square resistor 10, wherein:

[0053] Four winding inductors 7 are embedded in the first square dielectric plate 6, and four capacitor strips 8 and a first graphene square resistor 10 are located on a side of the first square dielectric plate 6 away from the first foam substrate 4;

[0054] Four capacitor strips 8 are arranged corresponding to the four sides of the first graphene square resistor 10, and capacitor through holes penetrating the first square dielectric plate 6 are provided at both ends of each capacitor strip 8;

[0055] One end of each winding inductor 7 is connected to one side of the first graphene square resistor 10 , and the other end is connected to the capacitor strip 8 through a via.

[0056] It should be noted that the first square dielectric plates of all the first units of the first lossy layer may be a whole dielectric plate.

[0057] Specifically, the first lossy layer 1 is located on the top layer. Except for the first square dielectric plate 6, the first unit of this first lossy layer 1 is separated from each other. A wire-wound inductor 7 is formed by using a capacitor strip 8 and vias to run between the upper and lower surfaces of the first square dielectric plate 6. Finally, one end of the wire-wound inductor 7 is threaded through the first square dielectric plate 6 and then connected to the first graphene square resistor 10 via a metal sheet. Therefore, because the inter-turn capacitance of the wire-wound inductor 7 is in parallel with the inductor itself, the inter-turn capacitance and its own inductance self-resonate. This parallel resonance causes the entire surface to exhibit a high impedance state, resulting in a broadband wave transmission response. The large inductance allows this high impedance state to be maintained over a wider frequency range, thus achieving broadband wave transmission of the first lossy layer 1 in the mid- and high-frequency range. Furthermore, the introduction of a capacitor strip with a capacitor via in the first lossy layer 1 allows it to enter into series resonance with the wire-wound inductor 7. This series resonance reduces the imaginary impedance component, rendering this layer lossy, thus enabling the first lossy layer 1 to absorb waves in the low-frequency portion of the operating band. Furthermore, the embodiment of the present invention, due to its wound inductor structure, can confine the magnetic field to the dielectric plate surrounded by the spiral wire. This effectively reduces the unit size while achieving a low-frequency absorption band, thereby delaying the frequency of grating lobes appearing under large angles of incidence.

[0058] Optionally, the thickness h1 of the first square dielectric plate 6 is 0.3-0.5 mm, the relative dielectric constant is 3-4, for example, 3.5, and the material of the first square dielectric plate 6 may be F4B350.

[0059] Optionally, the material of the capacitor strip is metal copper.

[0060] In an optional embodiment, the second lossy layer includes m×n second units arranged in an array, see Figure 3 Each second unit includes a second square dielectric plate 11, four planar spiral inductors 12, four metal strips 13, four metalized vias 14 and a second graphene square resistor 15, wherein:

[0061] Four planar spiral inductors 12 are located on a side of the second square dielectric plate 11 close to the first foam substrate 4 , and four metal strips 13 and a second graphene square resistor 15 are located on a side of the second square dielectric plate 11 close to the second foam substrate 5 ;

[0062] One end of the four metal strips 13 is connected to the four sides of the second graphene square resistor 15, and the other end is connected to the four planar spiral inductors 12 through metallized vias 14.

[0063] Furthermore, two adjacent second units are connected via a planar spiral inductor 12 .

[0064] It should be noted that the second square dielectric plates of all the second units of the second lossy layer may be a whole dielectric plate.

[0065] Specifically, the second lossy layer 2 utilizes a planar spiral inductor 12, and the planar spiral inductor 12 is connected in series with the metal strip 13. This allows the parasitic capacitance of the planar spiral inductor 12, the inductance of the metal strip 13, and the resistance of the second graphene square resistor 15 to resonate at high frequencies, thereby introducing an absorption band at high frequencies. Furthermore, this resonance is adjusted to a frequency close to the transmission band, thereby achieving low insertion loss broadband transmission while also achieving an absorption band at frequencies close to the transmission band, thereby reducing the transition bandwidth. Therefore, the planar spiral inductor 12 is introduced into the second lossy layer 2, so that the parasitic capacitance of the planar spiral inductor 12 resonates with its own inductance at mid-frequency and resonates with the mesh inductor (i.e., the inductance of the metal strip itself) at high frequencies, thereby achieving mid-frequency transmission and high-frequency absorption. In addition, since adjacent second units of the second lossy layer are interconnected via planar spiral inductors, all units are connected as a whole. Therefore, there is no resonant frequency based on a single second unit, thus avoiding the generation of high-order modes (i.e., high-order harmonics) by independent second units, thereby avoiding their destruction of the ultra-wideband absorbing response, and ultimately achieving an ultra-wideband absorbing response.

[0066] Optionally, the thickness h3 of the second square dielectric plate 11 ranges from 0.1 to 0.3 mm, the relative dielectric constant is from 1.7 to 2.5, for example, 2.2, and the material of the second square dielectric plate 11 may be F4B220.

[0067] Optionally, the material of the metal strip 13 is copper.

[0068] Among them, the first graphene square resistor and the second graphene square resistor are made by mixing graphene and carbon black to form ink, and then using screen printing technology to print the ink into the desired shape. After the ink dries, a layer of resistive film with certain conductive properties is formed, which can play the role of replacing resistors.

[0069] In an optional embodiment, the bandpass frequency selection layer includes m×n third units arranged in an array, see Figure 4 , Unit 3 includes:

[0070] a third square dielectric plate 16;

[0071] The fourth square dielectric plate 17 is located below the third square dielectric plate 16;

[0072] Twelve square metal patches 18, four square metal patches 18 arrayed on a side of the third rectangular dielectric plate 16 away from the fourth square dielectric plate 17, four square metal patches 18 arrayed on a side of the fourth square dielectric plate 17 close to the third rectangular dielectric plate 16, and four square metal patches 18 arrayed on a side of the fourth square dielectric plate 17 away from the third rectangular dielectric plate 16;

[0073] The annular gap metal patch 19 is located between the third square dielectric plate 16 and the fourth square dielectric plate 17 and has four annular gaps 20 distributed in an array and penetrating the annular gap metal patch.

[0074] It should be noted that the third rectangular dielectric plates of all third units of the second lossy layer can be a whole dielectric plate, the fourth square dielectric plates of all third units can also be a whole dielectric plate, and the annular gap metal patches of all third units can be a whole metal patch.

[0075] Specifically, four square metal patches 18 are set on the upper surface of each third-party rectangular dielectric plate 16, and four square metal patches 18 are set on the upper and lower surfaces of the fourth square dielectric plate 17 respectively. A ring-shaped gap metal patch 19 is also set between the third-party rectangular dielectric plate 16 and the fourth square dielectric plate 17. Four ring-shaped gaps 20 are set corresponding to the ring-shaped gap metal patch 19. The ring-shaped gap 20 can be a square ring-shaped gap, thereby forming a third-order bandpass frequency selection layer with a transmission band and a stop band. The third-order frequency selection can achieve a broadband passband, and the frequency-selective stop band is equivalent to a metal floor, which plays the role of reflecting electromagnetic waves. In the absorption band, the electromagnetic waves first pass through the loss layer and then are absorbed on the loss layer after frequency-selective reflection. Therefore, the bandpass frequency selection layer achieves broadband transmission of the intermediate frequency and provides a floor for low-frequency and high-frequency absorption.

[0076] Optionally, the thickness h5 of the third rectangular dielectric plate 16 and the fourth rectangular dielectric plate 17 are both in the range of 2.5-3 mm, and the relative dielectric constant is both in the range of 2-4. The material of the third rectangular dielectric plate 16 and the fourth square dielectric plate 17 can be F4B350.

[0077] Optionally, the length w4 of the square metal patch 18 is 3-4 mm, the material of the square metal patch 18 is metallic copper, the gap width g of the annular gap metal patch 19 is 0.1-0.2 mm, each gap of the annular gap metal patch 19 is a square gap, and the material of the annular gap metal patch 19 is metallic copper.

[0078] The broadband absorption and penetration integrated frequency-selective surface proposed by the present invention utilizes the resonance between the parasitic capacitance of the planar spiral inductor structure and the inductance of the metal grid, thereby introducing a high-frequency absorption band while maintaining the insertion loss of the transmission band. The high inductance of the planar spiral inductor of the broadband absorption and penetration integrated frequency-selective surface of the present invention and its parasitic capacitance can resonate to produce a broadband transmission band at the intermediate frequency. In addition, the metal grid is connected to the planar spiral inductor, and the non-resonant characteristics of the metal grid itself will not affect the transmission band. In addition, when the inductance value of the metal grid is appropriate, the metal grid resonates with the parasitic capacitance of the spiral inductor to produce a high-frequency absorption band.

[0079] The broadband absorption and penetration integrated frequency selective surface of the present invention broadens the absorption and penetration frequency selective absorption band and realizes a low insertion loss and wide wave transmission band. The use of the broadband absorption and penetration integrated frequency selective surface of the present invention can effectively reduce the radar wave scattering cross section of the antenna and can adapt to the use of ultra-wideband antennas.

[0080] In a specific embodiment, based on the above embodiment, a wide-band absorption-transmitting integrated frequency-selective surface is provided, which operates at 1.5GHz-18GHz, has a wave transmission band covering the entire X-band, and has an insertion loss of less than 1.3dB. The embodiment comprises, from top to bottom, a first lossy layer 1, a second lossy layer 2, and a bandpass frequency-selective layer 3. A first foam substrate 4 is provided between the first lossy layer 1 and the second lossy layer 2. The upper surface of the first foam substrate 4 is in contact with the first lossy layer 1, and the lower surface of the first foam substrate 4 is in contact with the upper surface of the second lossy layer 2; a second foam substrate 5 is provided between the second lossy layer 2 and the bottom bandpass frequency-selective layer 3. The upper surface of the second foam substrate 5 is in contact with the lower surface of the second lossy layer 2, and the lower surface of the second foam substrate 5 is in contact with the upper surface of the bottom bandpass frequency-selective layer 3; the first square dielectric plate of the first lossy layer 1 adopts a thickness of h1=0.5mm and a relative dielectric constant ε r1 = 3.5 dielectric; the second square dielectric plate 11 of the second lossy layer 2 has a thickness of h3 = 0.254mm, a relative dielectric constant ε r2= 2.2 dielectric; the third lossy layer 3 of the third-party dielectric plate 16 and the fourth square dielectric plate 17 are both made of thickness h5 = 2.8mm, relative dielectric constant ε r3 =3.5 medium. The first foam substrate 4 has a thickness of h2 = 12.3 mm and a relative dielectric constant ε r4 = 1 medium and the second foam substrate 5 has a thickness of h4 = 7 mm and a relative dielectric constant ε r5 =3.5 medium.

[0081] In order to further verify the effect of the specific broadband absorption and penetration integrated frequency selective surface, the following simulation was carried out, specifically:

[0082] Simulation 1, under vertical incidence conditions, the transmission curve (S21) and reflection curve (S11) of the absorption frequency selection and the absorption rate curve are simulated, and the results are as follows Figure 5 As shown. Figure 5 The curves show that this absorption frequency selection is a center-transmitting, side-absorbing type, achieving a wide matching bandwidth from 1.56 to 18 GHz, a relative bandwidth of 168%, and a reflectivity of less than -10 dB. Regarding the transmission band performance, measured by an insertion loss of 1.5 dB, the transmission band covers a frequency range of 7.15 to 12.4 GHz, with a relative bandwidth of 58% and a minimum insertion loss of 0.5 dB within the band. Furthermore, this absorption frequency selection maintains an insertion loss of less than 1.3 dB throughout the X-band, and its 1.2 dB relative transmission bandwidth reaches 40%.

[0083] Simulation 2, under the conditions of oblique incidence of TE (transverse electric wave) and TM (transverse magnetic wave) electromagnetic waves, the reflection coefficient curve and transmission coefficient curve of the embodiment are simulated when the incident angle of the electromagnetic wave increases from 0 degrees to 30 degrees, and the S parameter curve is obtained, as shown in FIG. Figure 6a and Figure 6b As shown. Among them, Figure 6a is the S parameter curve obtained under TE polarization, Figure 6b is the S parameter curve obtained under TM polarization. Figure 6a It can be seen that: under the TE polarization wave irradiation, the absorption frequency selection basically maintains its frequency response in the 0-30° oblique incidence range. However, when the incident angle reaches 30°, the high-frequency absorption band of the absorption frequency selection under TE polarization is reduced from 18GHz to 16GHz; Figure 6b It can be seen that under the irradiation of TM polarized waves, the absorption frequency selection basically maintains its frequency response in the range of 0-30° oblique incidence.

[0084] In the description of the present invention, the terms "first" and "second" are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. Therefore, a feature specified as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, "plurality" means two or more, unless otherwise specifically defined.

[0085] In the description of this specification, the reference terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" mean that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. 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 can be combined in any appropriate manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples described in this specification.

[0086] Although the present invention is described herein in conjunction with various embodiments, in the process of implementing the claimed invention, those skilled in the art can understand and implement other variations of the disclosed embodiments by reviewing the drawings, the disclosure, and the appended claims. In the claims, the word "comprising" does not exclude other components or steps, and "a" or "an" does not exclude multiple situations. A single processor or other unit can implement several functions listed in the claims. Certain measures are recorded in different dependent claims, but this does not mean that these measures cannot be combined to produce good results.

[0087] The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention cannot be considered to be limited to these descriptions. For those skilled in the art of the present invention, any modifications made without departing from the concept of the present invention should be deemed to fall within the scope of protection of the present invention.

Claims

1. A broadband absorption and penetration integrated frequency selective surface, characterized in that: The broadband absorption and penetration integrated frequency selective surface comprises: A first lossy layer, configured to transmit broadband waves in the mid- and high-frequency parts and absorb waves in the low-frequency part, the first lossy layer comprising m×n first units arranged in an array; a first foam substrate, located below the first lossy layer; A second lossy layer, located below the first foam substrate, is used for transmitting waves in the intermediate frequency portion and absorbing waves in the high frequency portion, the second lossy layer comprising m×n second units arranged in an array; a second foam substrate, located below the second lossy layer; a bandpass frequency selection layer, located below the second foam substrate, for transmitting broadband intermediate-frequency waves and providing a floor for absorbing low-frequency and high-frequency waves, the bandpass frequency selection layer comprising m×n third units arranged in an array; Each of the first units includes a first square dielectric plate, four wound inductors, four capacitor strips, eight capacitor through-holes and a first graphene square resistor, wherein: The four winding inductors are embedded in the first square dielectric plate, and the four capacitor strips and the first graphene square resistor are located on a side of the first square dielectric plate away from the first foam substrate; The four capacitor strips are arranged corresponding to the four sides of the first graphene square resistor, and capacitor through holes penetrating the first square dielectric plate are provided at both ends of each capacitor strip; One end of each of the winding inductors is connected to one side of the first graphene square resistor, and the other end is connected to the capacitor strip through a via.

2. The broadband absorption and penetration integrated frequency selective surface according to claim 1, characterized in that: The thickness of the first square dielectric plate is in the range of 0.3-0.5 mm, and the relative dielectric constant is in the range of 3-4.

3. The broadband absorption and penetration integrated frequency selective surface according to claim 1, characterized in that: Each of the second units includes a second square dielectric plate, four planar spiral inductors, four metal strips, four metalized vias and a second graphene square resistor, wherein: The four planar spiral inductors are located on a side of the second square dielectric plate close to the first foam substrate, and the four metal strips and the second graphene square resistor are located on a side of the second square dielectric plate close to the second foam substrate; One end of the four metal strips is connected to the four sides of the second graphene square resistor respectively, and the other end is connected to the four planar spiral inductors respectively through the metallized vias; Furthermore, two adjacent second units are connected via the planar spiral inductor.

4. The broadband absorption-through integrated frequency selective surface according to claim 3, characterized in that: The thickness of the second square dielectric plate is in the range of 0.1-0.3 mm, and the relative dielectric constant is in the range of 1.7-2.

5.

5. The broadband absorption and penetration integrated frequency selective surface according to claim 1, characterized in that: The third unit includes: a third square dielectric plate; a fourth square dielectric plate, located below the third square dielectric plate; Twelve square metal patches, four of which are distributed on a side of the third square dielectric plate away from the fourth square dielectric plate, four of which are distributed on a side of the fourth square dielectric plate close to the third square dielectric plate, and four of which are distributed on a side of the fourth square dielectric plate away from the third square dielectric plate; The annular gap metal patch is located between the third square dielectric plate and the fourth square dielectric plate and has four annular gaps distributed in an array and passing through the annular gap metal patch.

6. The broadband absorption and penetration integrated frequency selective surface according to claim 5, characterized in that: The thickness of the third square dielectric plate and the fourth square dielectric plate are both in the range of 2.5-3 mm, and the relative dielectric constant is both in the range of 2-4.

7. The broadband absorption and penetration integrated frequency selective surface according to claim 1, characterized in that: The thickness of the first foam substrate ranges from 11 to 13 mm, and the relative dielectric constant ranges from 1 to 1.

2.

8. The broadband absorption-through integrated frequency selective surface according to claim 1, characterized in that: The thickness of the second foam substrate is in the range of 6-8 mm, and the relative dielectric constant is in the range of 1-1.2.

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