Reconfigurable absorption and transmission integrated frequency selective surface

Abstract

The invention provides a wave-transparent band frequency-adjustable frequency selection surface, which comprises a loss layer, a frequency selection layer and a bias network, the loss layer and the frequency selection layer are periodically arranged, the loss layer comprises a first resonant structure and a second resonant structure, and the frequency selection layer comprises a third resonant structure. The upper bias network and the lower bias network are respectively connected with direct-current voltages with different polarities, so that the variable capacitance diodes in the first resonant structure and the third resonant structure work under different voltages to generate different capacitance values, the resonant frequency point of the loss layer and the resonant frequency point of the frequency selection layer in the structures generate frequency shift at the same time, and finally continuous adjustability in the wave-transparent frequency band of 5.51 GHz to 6.31 GHz is achieved. Under the action of the second resonant structure and other lumped resistors of the loss layer, wave absorption within the frequency band range of 4.31 GHz to 5.15 GHz and the frequency band range of 6.31 GHz to 13.81 GHz is achieved. The device has the characteristics of continuous frequency modulation and out-of-band wave absorption, can effectively suppress interference of outside electromagnetic waves in other frequency bands or electromagnetic waves in a frequency band close to a communication frequency band on communication, can reduce the radar cross section of a target, and is beneficial to target stealth.

Description

Technical Field

[0001] The present invention belongs to the field of communication technologies, and further relates to a reconfigurable absorption and transmission integrated frequency selective surface in the field of electromagnetic fields and microwave technologies, which can be used for communication anti-interference and stealth radar radomes. Background Art

[0002] As an important communication equipment in an aircraft, an antenna undertakes the task of communicating between the aircraft and the outside world. An antenna radome is loaded outside the antenna to reduce the scattering of the antenna. In order not to affect the radiation characteristics of the antenna, an absorption and transmission integrated frequency selective surface is proposed, which has both wave absorption and wave transmission characteristics at the same time. Due to the almost lossless wave transmission characteristic of the absorption and transmission integrated material for electromagnetic waves in the communication frequency band, the target cannot be stealthy and is vulnerable to interference in the communication frequency band. Therefore, the reconfigurable characteristic is proposed. By loading active components onto the passive absorption and transmission integrated material and adjusting the parameters of the active components, the unit characteristics of the absorption and transmission integrated material are changed, so as to change the characteristics of the material for electromagnetic waves to achieve the reconfigurable characteristic. However, due to the loading of active components and their bias circuits, impedance mutations occur with the change of the working state of the active components, leading to the problem of narrowing of the wave absorption bandwidth of the absorption and transmission integrated frequency selective surface, and it is impossible to take into account both the reconfigurable characteristic and the broadband wave absorption characteristic, which has certain limitations. Summary of the Invention

[0003] In order to overcome the above-mentioned disadvantages of the prior art, the present invention proposes a reconfigurable absorption and transmission integrated frequency selective surface, aiming to solve the problem that the transmission characteristics and broadband wave absorption of the existing absorption and transmission integrated frequency selection structure cannot be satisfied at the same time. The present invention can achieve anti-interference and out-of-band target stealth at the same time when the antenna is working normally, improving the communication quality and stability.

[0004] In order to achieve the above object, the technical solution adopted by the present invention is:

[0005] A reconfigurable absorption and transmission integrated frequency selective surface is composed of a plurality of reconfigurable absorption and transmission integrated units arranged in a periodic manner with the same structure. The reconfigurable absorption and transmission integrated unit includes a bias network and a loss layer, an air layer and a frequency selection layer arranged in sequence; the loss layer includes a first resonant structure, a second resonant structure and a metal stub; a resistor is embedded in the metal stub.

[0006] The first resonant structure includes a metal ring and an annular metal patch nested in the metal ring. A plurality of first varactor diodes are connected by a gap between the two. The outer edge of the metal ring is connected to the metal stub, converting the energy of low-frequency electromagnetic waves into heat energy through resonance.

[0007] The second resonant structure includes the annular metal patch and a first circular metal patch nested in the annular metal patch. A plurality of lumped resistors are connected by a gap between the two, converting the energy of high-frequency electromagnetic waves into heat energy through resonance.

[0008] In one embodiment, the first resonant structure and the second resonant structure have the same center, and an xoy coordinate system is established with this center as the coordinate origin;

[0009] The number of the first varactor diodes is four, which are respectively located on the positive and negative half-axes of the x-axis and y-axis at the same distance.

[0010] In one embodiment, the number of the lumped resistors is four, which are respectively located in the directions at a 45° angle to the x-axis and y-axis at the same distance.

[0011] In one embodiment, the frequency selective layer includes a third resonant structure, which forms a multi-layer cascaded structure with the first resonant structure and the second resonant structure to broaden the absorption bandwidth and realize the reconfigurable characteristic;

[0012] The third resonant structure includes a square loop metal patch and a second circular metal patch nested inside the square loop metal patch, and four second varactor diodes are connected by the gap between the two;

[0013] The bias network connects the positive electrodes and negative electrodes of all the varactor diodes together respectively, controls the voltages of all the varactor diodes to change simultaneously, and realizes the simultaneous movement of the transmission frequency points.

[0014] In one embodiment, the four second varactor diodes are respectively opposite to the positions of the four first varactor diodes.

[0015] In one embodiment, the bias network includes an upper-layer bias network, a lower-layer bias network and an intermediate bias line;

[0016] The upper-layer bias network includes upper-layer metal branches connected to the metal ring, the lower-layer bias network includes lower-layer metal branches connected to the second circular metal patch, and the intermediate bias line connects the first circular metal patch and the lower-layer metal branches.

[0017] In one embodiment, the first resonant structure, the second resonant structure and the metal branches are located on the upper surface of the upper dielectric substrate, the upper-layer metal branches are located on the lower surface of the upper dielectric substrate, and there are first metal vias and second metal vias on the upper dielectric substrate;

[0018] The third resonant structure is located on the lower surface of the lower dielectric substrate, the lower-layer metal branches are located on the upper surface of the lower dielectric substrate, and there is a third metal via on the lower dielectric substrate;

[0019] The upper metal stub is connected to the metal ring through a first metal via, the middle bias line is connected to the first circular metal patch through a second metal via, and the metal ring and the first circular metal patch are respectively connected to the positive and negative electrodes of a first varactor diode; the lower metal stub is connected to the second circular metal patch through a third metal via, the square ring metal patch and the second circular metal patch are respectively connected to the positive and negative electrodes of a second varactor diode, and the diodes are regulated by applying a DC voltage to the bias network and the frequency selection layer.

[0020] In one embodiment, the first varactor diode is the same as the second varactor diode. The lower metal stub is V-shaped, one arm is in the x-axis direction and is located at the edge of the unit for connecting the unit to an external circuit, and the other arm has an angle with the x-axis direction for connecting the varactor diode.

[0021] In one embodiment, the metal stub is composed of four first metal stubs and four second metal stubs;

[0022] The four first metal stubs respectively extend along the positive and negative half axes of the x-axis and the y-axis to the unit boundary;

[0023] The four second metal stubs respectively extend towards the four corners of the unit at an angle of 45° with the x-axis and the y-axis.

[0024] In one embodiment, a first resistor is provided on each first metal stub, and the first resistor is located at a position of the first metal stub close to the metal ring;

[0025] A second resistor is provided on each second metal stub, and the second resistor is located at the midpoint of the second metal stub.

[0026] Compared with the prior art, the advantages of the present invention are as follows:

[0027] First, since the loss layer first resonance structure in the present invention is connected to four metal stubs embedded with resistors, it creates conditions for the resonance of low-frequency electromagnetic waves, and converts the energy of low-frequency electromagnetic waves into heat energy through resonance. At the same time, the loss layer contains a second resonance structure. A circular metal patch is placed inside the annular metal patch of the first resonance structure, and there is an annular gap between the annular metal patch and the circular metal patch, creating conditions for the resonance of high-frequency electromagnetic waves. Four equal-value resistors are uniformly loaded on the circular gap, and the energy of high-frequency electromagnetic waves can be converted into heat energy through resonance. By designing two resonance structures in the loss layer, the present invention has the ability to absorb both low-frequency and high-frequency electromagnetic waves simultaneously, realizing stable broadband wave absorption.

[0028] Second, based on the loss layer design, four variable capacitance diodes are evenly loaded at the circular aperture of the first resonant structure, and four identical variable capacitance diodes are loaded at the same position of the arc-shaped metal hole of the frequency selection layer. A bias network is used to connect the positive and negative electrodes of all diodes together, and the voltages of all diodes are controlled to change simultaneously to achieve simultaneous movement of the transmission frequency. Since the loss layer has more lumped resistance elements and can achieve broadband absorption, the diode has little effect on the characteristic impedance of the loss layer, and can simultaneously achieve broadband absorption and tunable transmission functions.

[0029] Third, the present invention uses the bias network and the structure itself to feed all diodes. The middle through hole passes through the loss layer dielectric substrate and is connected to the V-shaped bias network, connecting all the diode positive poles together. The bias network is added to the bottom of the top dielectric substrate and connected to the loss layer diode negative pole through the through hole. The diode is regulated by applying a DC voltage to the bias network and the frequency selection layer, which has the characteristics of a simple bias network structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of the structure of the reconfigurable absorption-through integrated unit frequency selective surface unit of the present invention.

[0031] Figure 2 is a top view of a sacrificial layer of the present invention.

[0032] Figure 3 It is a top view of the frequency selection layer of the present invention.

[0033] Figure 4 It is a schematic diagram of the feeding method of the present invention.

[0034] Figure 5 It is a schematic diagram of S parameter characteristics of an embodiment of the present invention in a simulation experiment. DETAILED DESCRIPTION

[0035] The embodiments of the present invention are described in detail below with reference to the accompanying drawings and examples.

[0036] The existing integrated absorption and penetration frequency selective surface cannot take into account both the reconfigurable characteristics and the broadband absorption characteristics due to the limited absorption bandwidth. To this end, the present invention provides a reconfigurable integrated absorption and penetration frequency selective surface, which is composed of a plurality of reconfigurable integrated absorption and penetration units with the same structure arranged periodically.

[0037] Reference Figure 1 The reconfigurable absorption-through integrated unit of the present invention comprises a loss layer 1, an air layer 2, a frequency selection layer 3 and a bias network 4. The loss layer 1, the air layer 2 and the frequency selection layer 3 are arranged from top to bottom, and the bias network 4 connects certain parts of the loss layer 1 and the frequency selection layer 3 to feed the diode device in the unit.

[0038] The structure of loss layer 1 is as follows Figure 2As shown in the figure, it includes a first resonant structure 12, a second resonant structure 13 and a metal stub 14. In an embodiment of the present invention, the first resonant structure 12, the second resonant structure 13, the metal stub 14 and the resistor 17 are all arranged on the upper surface of the upper dielectric substrate 11.

[0039] Among them, the first resonant structure 12 includes a metal ring 121 and an annular metal patch 122. The annular metal patch 122 is nested inside the metal ring 121, and the two are preferably concentrically arranged, especially preferably both located at the center of the unit. There is a gap with a certain width between the metal ring 121 and the annular metal patch 122, creating conditions for the resonance of low-frequency electromagnetic waves. In the area composed of the metal ring 121 and the annular metal patch 122, electromagnetic waves resonate at the gap to generate a transmission band. A number of first varactor diodes 123 are loaded in this gap, that is, the positive and negative electrodes of the first varactor diodes 123 are respectively connected to the metal ring 121 and the annular metal patch 122, or respectively connected to the annular metal patch 122 and the metal ring 121. The metal stub 14 is connected to the outer edge of the metal ring 121 and preferably extends radially outward, and a resistor 17 is loaded thereon to convert the low-frequency electromagnetic wave energy into heat energy through resonance.

[0040] The second resonant structure 13 includes a first circular metal patch 132 and the annular metal patch 122. The first circular metal patch 132 is nested inside the annular metal patch 122, and the two are preferably concentrically arranged, especially preferably both located at the center of the unit. The first circular metal patch 132 and the annular metal patch 122 also have a gap with a certain width, creating conditions for the resonance of high-frequency electromagnetic waves. A number of lumped resistors 133 are loaded in this gap, that is, the two ends of the lumped resistors 133 are respectively connected to the first circular metal patch 132 and the annular metal patch 122. The second resonant structure 13 is inside the first resonant structure 12 and has a relatively small overall size, which can make high-frequency electromagnetic waves resonate at the annular gap, and convert the electromagnetic wave energy into heat energy through the four lumped resistors 133 to achieve the absorption of high-frequency electromagnetic waves.

[0041] By designing the first resonant structure 12 and the second resonant structure 13 in the loss layer 1 in the present invention, it enables the structure to have the ability to absorb both low-frequency and high-frequency electromagnetic waves simultaneously, achieving stable broadband wave absorption.

[0042] In a further embodiment of the present invention, the upper dielectric substrate 11 is a Rogers RO4003 dielectric substrate with a relative dielectric constant of 3.55, a loss tangent of 0.02, and a thickness of 0.5 mm. The dielectric substrate provides an electrical insulation layer between metal components, which can avoid the short-circuit situation due to the existence of current between structures and provide support for the metal patch structure.

[0043] In a further embodiment of the present invention, there are a total of four first varactor diodes 123 provided between the metal ring 121 and the annular metal patch 122, which are evenly distributed. The first resonant structure 12 and the second resonant structure 13 have the same center, which is the unit center. Taking the unit center as the coordinate origin, an xoy coordinate system is established. The four first varactor diodes 123 are respectively located on the positive and negative semi-axes of the x-axis and y-axis at the same distance. Exemplarily, each first varactor diode 123 adopts SMV2201-040LF, whose capacitance value can vary uniformly with the change of the voltage across the diode. The voltage change range is 20V to 14V, and the capacitance value change range is 0.23pF to 0.27pF. Its equivalent circuit is a resistor in series with a parallel inductor and capacitor. By changing the bias voltage across the first varactor diode 123, its capacitance value is changed, and then the resonant frequency of the first resonant structure 12 is changed to realize the adjustable passband frequency band of the lossy layer 1.

[0044] In a further embodiment of the present invention, the metal branch 14 is composed of four first metal branches 141 and four second metal branches 142, that is, the metal ring 121 of the first resonant structure 12 is connected to eight metal branches 14. The eight metal branches 14 are centered on the metal ring 121 and evenly point to the eight directions of the unit. A resistor 17 is provided on each metal branch 14. Among them, the four first metal branches 141 extend along the positive and negative semi-axes of the x-axis and y-axis to the unit boundary respectively. A first resistor 171 is provided on each first metal branch 141. When absorbing low-frequency waves, the first resistor 171 plays a major role, and the current is mainly concentrated at the position of the first metal branch 141 close to the metal ring 121. Therefore, in the embodiment of the present invention, the first resistor 171 is designed to be located at the position of the first metal branch 141 close to the metal ring 121. By setting the first resistor 171, the incident low-frequency electromagnetic wave energy can be converted into heat energy to realize the absorption of low-frequency electromagnetic waves. The four second metal branches 142 extend to the four corners of the unit at an angle of 45° with the x-axis and y-axis. A second resistor 172 is provided on each second metal branch 142; when absorbing high-frequency waves, due to resonance, the electromagnetic wave energy is distributed at the circular metal gap. By setting the second resistor 172, part of the incident electromagnetic wave energy can be converted into heat energy to realize the absorption of high-frequency electromagnetic waves.

[0045] In a further embodiment of the present invention, the number of the lumped resistors 133 is four, which are evenly distributed, and are respectively located at the same distance in the direction of 45° with the x-axis and y-axis, and straddle the gap between the annular metal patch 122 and the circular metal patch 132.

[0046] In a further embodiment of the present invention, as shown in the reference figure, the frequency selective layer 3 includes a third resonant structure 32, and the third resonant structure 32 can be arranged on the lower surface of the lower dielectric substrate 31 to form a multi-level cascade structure with the first resonant structure 12 and the second resonant structure 13 to broaden the absorption bandwidth and achieve reconfigurable characteristics. The lower dielectric substrate 31 is made of the same material as the upper dielectric substrate 11. The third resonant structure 32 includes a second circular metal patch 323 and a square ring metal patch 321. The outer contour size of the square ring metal patch 321 is the same as that of the unit, and its center is a metal hole 322 with arcs at all four corners. The second circular metal patch 323 is arranged in the metal hole 322, and there is a gap with a certain width between the second circular metal patch 323 and the square ring metal patch 321. Four uniformly distributed second varactor diodes 324 are loaded in this gap, that is, the positive and negative electrodes of the second varactor diode 324 are respectively connected to the second circular metal patch 323 and the square ring metal patch 321, or respectively connected to the square ring metal patch 321 and the second circular metal patch 323. The second varactor diode 324 is opposite to the first varactor diode 123 in position and has the same model. The SMV2201-040LF is adopted, the voltage change range is 20V to 12V, and the capacitance value change range is 0.23pF to 0.29pF. Its equivalent circuit is a resistor in series with a parallel inductor and capacitor. By changing the bias voltage across the second varactor diode 324 to change its capacitance value, the transmission band of the frequency selective layer 3 can be adjusted.

[0047] In the present invention, the bias network 4 connects the positive and negative electrodes of all varactor diodes together respectively, controls the voltages of all varactor diodes to change simultaneously, and realizes the simultaneous movement of the transmission frequency points.

[0048] Reference Figure 4 As shown, the bias network 4 of the present invention mainly includes an upper bias network 41, a lower bias network 42 and an intermediate bias line 43. Among them, the upper bias network 41 includes an upper metal branch 411. The upper metal branch 411 is preferably located on the lower surface of the upper dielectric substrate 11. Further, it can be connected to the metal ring 121 through the first metal through hole 412 on the upper dielectric substrate 11. The metal ring 121 and the first circular metal patch 132 are respectively connected to the positive and negative electrodes of the first varactor diode 123.

[0049] The lower bias network 42 includes a lower metal branch 421. The lower metal branch 421 is preferably located on the upper surface of the lower dielectric substrate 31. It can be connected to the second circular metal patch 323 through the third metal through hole 422 on the lower dielectric substrate 31. The square ring metal patch 321 and the second circular metal patch 323 are respectively connected to the positive and negative electrodes of the second varactor diode 324.

[0050] There is also a second metal via 432 on the upper dielectric substrate 11. The intermediate bias line 43 is connected to the first circular metal patch 132 through the second metal via 432 and is connected to the lower metal stub 421. Further, the intermediate bias line 43 includes a metal post 431 which is arranged in the vertical direction and passes through the second metal via 432. Further, the first metal via 412 is directly connected to the negative electrode of the first varactor diode 123, and the metal post 431 is directly connected to the positive electrode of the first varactor diode 123 and is connected to the lower bias network 42.

[0051] Thus, by applying a DC voltage to the bias network 4 and the frequency selective layer 3, the regulation of the diode can be achieved. Specifically, when the electromagnetic wave operates in the transmission frequency band, the upper bias network 41 and the lower bias network 42 apply DC voltages to the first varactor diode 123 and the second varactor diode 324 simultaneously. When the voltage across the diode is changed, the capacitance value of the diode can also be changed accordingly, thereby realizing the continuous adjustment of the transmission frequency band of the frequency selective surface within a specific frequency band. According to the design of the integrated absorption and transmission frequency selective surface unit, broadband absorption of electromagnetic wave energy is realized outside the transmission frequency band.

[0052] Further preferably, the lower metal stub 421 of the present invention is in a "V" shape, one arm is in the x-axis direction, and the other arm has an angle with the x-axis direction. Since the lower metal stub 421 is used to feed the negative electrodes of all the diodes, the electric arm in the x-axis direction is located at the edge of the unit and is used to connect the unit to the external circuit, and the other arm is connected to the metal post 431 and is used to connect the negative electrodes of all the diodes; and the other arm has an angle with all the diodes, weakening the inductive capacitance with the diodes and reducing the influence of the feeder on the transmission performance.

[0053] The working principle of the present invention is:

[0054] The reconfigurable integrated absorption and transmission unit of the present invention is mainly composed of a loss layer 1, an upper bias network 41, an air layer 2, a lower bias network 42 and a frequency selective layer 3 cascaded from top to bottom. During the electromagnetic wave communication in the C band, affected by the electromagnetic waves with similar frequencies, different DC voltages can be applied to all the varactor diodes simultaneously through the bias network 4, continuously changing the capacitance value of the diodes, realizing the continuous adjustment of the transmission frequency band, and improving the wireless communication quality. At the same time, since the loss layer 1 is loaded with a resistor 17 that absorbs low-frequency electromagnetic waves and a second resonant structure 13 that absorbs high-frequency electromagnetic waves, the absorption of electromagnetic waves on both sides outside the transmission band can be realized, achieving electromagnetic stealth, and thus can be applied to the target radome.

[0055] The following further illustrates the technical effects of the present invention in combination with simulation experiments:

[0056] The outer radius of the designed metal ring 121 is 3.8 mm, and the inner radius is 3.6 mm. The outer ring radius of the annular metal patch 122 is 2.8 mm, and the inner ring radius is 2.5 mm. The length of the first metal stub 141 is 1.5 mm, and the width is 1 mm. The first resistor 171 thereon is located near the first resonant structure metal ring 121, 0.2 mm away from the outer ring of the metal ring 121, and the resistance value is 200 Ω. The length of the second metal stub 142 is 1.2 mm, and the width is 1 mm. The second resistors 172 on the four second metal stubs 142 are located at the midpoints of the metal stubs, and the resistance value is 270 Ω. The radius of the first circular metal patch 132 is 2.4 mm. There is an annular gap between the annular metal patch 122 and the metal ring 132. One side of the lumped resistor 133 is loaded on the annular metal patch 122, and the other side is loaded on the first circular metal patch 132, with a resistance value of 270 Ω. The metal hole 322 is a square with a side length of 8.3 mm, and the fillet radius at the four corners is 3 mm. The second circular metal patch 323 is a square with a side length of 6.4 mm, and the fillet radius is 3 mm. The length of the upper metal stub 411 is 14.55 mm, and the width is 0.1 mm. The height of the first metal via 412 is 0.255 mm, and the radius is 0.07 mm. One arm of the lower metal stub 421 in the x-axis direction has a length of 14.55 mm and a width of 0.1 mm, and one arm in the hypotenuse direction has a length of 10 mm and a width of 0.1 mm. The height of the third metal via 422 is 0.255 mm, and the radius is 0.07 mm. The height of the metal post 431 is 7.755 mm, and the radius is 0.07 mm. The height of the second metal via 432 is 0.255 mm, and the radius is 0.07 mm.

[0057] The S-parameter curves obtained by modeling and simulating the embodiment of the present invention using the commercial simulation software ANSYS HFSS 2023 are as Figure 5 shown. Figure 5 The abscissa in [] is the frequency value, with the unit of GHz, and the ordinate is the S parameter, with the unit of dB. Figure 5 The black solid line in [] is the transmission coefficient |S 21 | curve, and the black dashed line is the reflection coefficient |S 11 | curve.

[0058] Refer to Figure 5When the capacitance values of the varactor diodes in the loss layer and the frequency selective layer change to 0.23 pF simultaneously according to the supply voltage, the through-waveband frequency with a transmission coefficient above -3 dB is 5.93 GHz to 6.31 GHz. When the capacitance values of the varactor diodes in the loss layer and the frequency selective layer change to 0.26 pF simultaneously according to the supply voltage, the through-waveband frequency with a transmission coefficient above -3 dB is 5.73 GHz to 6.09 GHz. When the capacitance values of the varactor diodes in the loss layer and the frequency selective layer change to 0.29 pF simultaneously according to the supply voltage, the through-waveband frequency with a transmission coefficient above -3 dB is 5.51 GHz to 5.82 GHz.

[0059] Since the capacitance values of the varactor diodes are linearly continuous, the through-waveband frequency can be continuously adjusted according to different capacitance values of the varactor diodes, and the adjustment range includes 5.51 GHz to 6.31 GHz.

[0060] In addition, due to the design of the metal branches with loading resistors and the second resonance structure in the loss layer, while continuously tuning the through-wave frequency band through the varactor diodes, absorption of electromagnetic waves outside the band can be achieved, and the absorption range is stably maintained at 4.31 GHz to 5.15 GHz and 6.31 GHz to 13.81 GHz.

[0061] Although the specific implementation manners of the present invention have been described in detail with reference to the accompanying drawings, it should not be construed as a limitation on the protection scope of this patent. Within the scope described in the claims, various modifications and deformations that can be made by those skilled in the art without creative efforts still fall within the protection scope of this patent.

[0062] As mentioned above, the above are only the preferred embodiments of the present invention, and do not impose any form of limitation on the present invention. Any simple modifications and equivalent changes made to the above embodiments based on the technical essence of the present invention all fall within the protection scope of the present invention.

Claims

1. A reconfigurable integrated absorption and penetration frequency selective surface is composed of a periodic arrangement of multiple reconfigurable integrated absorption and penetration units with the same structure, and is characterized in that, The reconfigurable integrated absorption and penetration unit includes a bias network (4), a loss layer (1), an air layer (2), and a frequency selective layer (3) arranged in sequence; the loss layer (1) includes a first resonant structure (12), a second resonant structure (13), and a metal stub (14); a resistor (17) is embedded in the metal stub (14). The first resonant structure (12) includes a metal ring (121) and an annular metal patch (122) nested within the metal ring (121). A gap between the two is connected to a number of first varactor diodes (123). The outer edge of the metal ring (121) is connected to the metal stub (14), converting the energy of low-frequency electromagnetic waves into heat through resonance. The second resonant structure (13) includes the annular metal patch (122) and a first circular metal patch (132) nested within the annular metal patch (122). A gap between the two is connected to a number of lumped resistors (133), converting the energy of high-frequency electromagnetic waves into heat through resonance.

2. The reconfigurable integrated frequency selective surface according to claim 1, wherein The first resonant structure (12) and the second resonant structure (13) have the same center. An xoy coordinate system is established with this center as the coordinate origin. The number of the first varactor diodes (123) is four, which are respectively located on the positive and negative semi-axes of the x-axis and y-axis at the same distance.

3. The reconfigurable integrated frequency selective surface according to claim 2, wherein The number of the lumped resistors (133) is four, which are respectively located in the directions at a 45° angle to the x-axis and y-axis at the same distance.

4. The reconfigurable integrated frequency selective surface according to claim 2, wherein The frequency selective layer (3) includes a third resonant structure (32), which forms a multi-layer cascade structure with the first resonant structure (12) and the second resonant structure (13) to broaden the absorption bandwidth and achieve reconfigurable characteristics. The third resonant structure (32) includes a square ring metal patch (321) and a second circular metal patch (323) nested within the square ring metal patch (321). A gap between the two is connected to four second varactor diodes (324). The bias network (4) connects the positive and negative electrodes of all varactor diodes together respectively, controlling the simultaneous change of the voltages of all varactor diodes to achieve the simultaneous movement of the transmission frequency points.

5. The reconfigurable integrated frequency selective surface for both absorption and penetration according to claim 4, characterized in that, The four second varactor diodes (324) are respectively opposite to the positions of the four first varactor diodes (123).

6. The reconfigurable integrated frequency selective surface for both absorption and penetration according to claim 4, wherein The bias network (4) includes an upper layer bias network (41), a lower layer bias network (42), and an intermediate bias line (43). The upper layer bias network (41) includes an upper layer metal stub (411) connected to the metal ring (121). The lower layer bias network (42) includes a lower layer metal stub (421) connected to the second circular metal patch (323). The intermediate bias line (43) connects the first circular metal patch (132) and the lower layer metal stub (421).

7. The reconfigurable integrated frequency selective surface for both absorption and penetration according to claim 6, wherein The first resonant structure (12), the second resonant structure (13), and the metal stub (14) are located on the upper surface of the upper dielectric substrate (11). The upper layer metal stub (411) is located on the lower surface of the upper dielectric substrate (11). The upper dielectric substrate (11) has a first metal via hole (412) and a second metal via hole (432). The third resonant structure (32) is located on the lower surface of the lower dielectric substrate (31), the lower metal stub (421) is located on the upper surface of the lower dielectric substrate (31), and a third metal via hole (422) is provided on the lower dielectric substrate (31); The upper metal stub (411) is connected to the metal ring (121) through a first metal via hole (412), the intermediate offset line (43) is connected to the first circular metal patch (132) through a second metal via hole (432), and the metal ring (121) and the first circular metal patch (132) are respectively connected to the positive and negative electrodes of the first varactor diode (123); the lower metal stub (421) is connected to the second circular metal patch (323) through a third metal via hole (422), and the square ring metal patch (321) and the second circular metal patch (323) are respectively connected to the positive and negative electrodes of the second varactor diode (324). The diodes are regulated by applying a DC voltage to the bias network (4) and the frequency selection layer (3).

8. The reconfigurable integrated frequency selective surface according to claim 7, characterized in that The first varactor diode (123) is the same as the second varactor diode (324). The lower metal stub (421) is V-shaped, one arm is in the x-axis direction and is located at the edge of the unit for connecting the unit to an external circuit, and the other arm has an angle with the x-axis direction for connecting the varactor diode.

9. The reconfigurable integrated frequency selective surface for both absorption and penetration according to any one of claims 2 to 8, characterized in that, The metal stub (14) is composed of four first metal stubs (141) and four second metal stubs (142); The four first metal stubs (141) respectively extend along the positive and negative half axes of the x-axis and y-axis to the unit boundary; The four second metal stubs (142) respectively extend towards the four corners of the unit at an angle of 45° with the x-axis and y-axis.

10. The reconfigurable integrated frequency selective surface according to claim 9, characterized in that, A first resistor (171) is provided on each first metal stub (141), and the first resistor (171) is located at a position of the first metal stub (141) close to the metal ring (121); A second resistor (172) is provided on each second metal stub (142), and the second resistor (172) is located at the midpoint of the second metal stub (142).

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