Metasurface absorber and array thereof, nonlinear circuit

Abstract

This application provides a metasurface absorber and its array, as well as a nonlinear circuit. The metasurface absorber includes a dielectric substrate with: a first metal sheet disposed on a first surface of the dielectric substrate, the edge of the first metal sheet coinciding with the edge of the first surface; and a second metal sheet disposed on a second surface of the dielectric substrate, two opposite edges of the second metal sheet not coinciding with corresponding edges of the second surface, and the remaining edge of the second metal sheet coinciding with the remaining edge of the second surface. The second metal sheet has a lumped port, dividing it into two sub-metal sheets symmetrically arranged about the lumped port, with the lumped port extending from one of the opposite edges to the other. Each sub-metal sheet has a rectangular slot, wherein the two rectangular slots on the two sub-metal sheets are symmetrically arranged about the lumped port. This application provides a metasurface absorber that achieves dual-frequency waveform selection and features a small frequency ratio.

Description

Technical Field

[0001] The disclosed embodiments of this application relate to the field of wireless communication technology, and more specifically, to a metasurface absorber and its array, and a nonlinear circuit. Background Technology

[0002] With the rapid development of modern electronics and communication technologies, electromagnetic interference has become an increasingly prominent problem. Electromagnetic interference not only affects the normal operation of electronic equipment but may also pose a potential threat to human health. Therefore, developing effective electromagnetic wave absorption and shielding technologies is crucial for improving electromagnetic compatibility and protecting the stability of wireless communications.

[0003] Microwave absorbers, as a class of highly efficient electromagnetic energy management devices, can significantly absorb and dissipate electromagnetic waves within a specific frequency range, while effectively suppressing electromagnetic wave reflection, transmission, and scattering. They play an important role in various fields such as electromagnetic shielding, communication technology, radar stealth, and energy harvesting. Early microwave absorber designs, such as Salisbury screens or magnetic absorbers using dielectric and ferrite materials, were simple in construction but often expensive, bulky, and thick, providing only limited frequency bandwidth.

[0004] With the development of metamaterials and metasurface technologies, these artificially manufactured periodic structures offer new possibilities for the precise manipulation of electromagnetic waves through the fine control of their subwavelength-level geometry. As two-dimensional equivalents of metamaterials, metasurfaces are rapidly emerging in numerous scientific and engineering fields due to their unique electromagnetic properties and broad application prospects, such as realizing unconventional refraction / reflection effects, holographic image construction, focusing functions, polarization state conversion, and the design of high-performance antennas and microwave absorbers.

[0005] Among them, microwave metasurface absorbers, which combine the characteristics of metasurface technology and microwave absorbers, offer advantages over traditional absorbers such as lower cost, thinner and lighter design, and simpler manufacturing, thus attracting widespread attention from the research and engineering communities. Multi-frequency metasurface absorbers, such as dual-frequency metasurface absorbers, are currently in high demand in practical applications. However, the design of current dual-frequency metasurface absorbers lacks flexibility and is limited by operating conditions; these are key issues that need to be considered and addressed in practical applications. Summary of the Invention

[0006] According to embodiments of this application, this application proposes a metasurface absorber and its array, as well as a nonlinear circuit, to solve the above-mentioned problems.

[0007] According to an aspect of this application, an exemplary metasurface absorber is disclosed, comprising a dielectric substrate on which are disposed: a first metal sheet disposed on a first surface of the dielectric substrate, the edge of the first metal sheet coinciding with the edge of the first surface; and a second metal sheet disposed on a second surface of the dielectric substrate, wherein the second surface is disposed opposite to the first surface, two opposite edges of the second metal sheet are not coincident with corresponding edges of the second surface, and the remaining edge of the second metal sheet coincides with the remaining edge of the second surface; wherein the second metal sheet is provided with a lumped port such that the second metal sheet is divided into two sub-metal sheets symmetrically disposed about the lumped port, and the lumped port extends from one edge of the two opposite edges to the other edge; each sub-metal sheet is provided with a rectangular groove, wherein the two rectangular grooves on the two sub-metal sheets are symmetrically disposed about the lumped port.

[0008] In some embodiments, the second metal sheet is provided with a port slot to serve as the lumped port, the port slot extending from one of the two opposing edges to the other edge.

[0009] In some embodiments, the length direction of the rectangular groove is consistent with the extension direction of the port groove, and the width of the rectangular groove is smaller than the width of the port groove.

[0010] In some embodiments, the two ends of the rectangular groove are equidistant from the corresponding edges of the two edges in the longitudinal direction.

[0011] In some embodiments, the distance between the rectangular slot and the port slot is a preset value.

[0012] In some embodiments, the two edges are equidistant from the corresponding edges of the second surface.

[0013] According to an aspect of this application, an exemplary nonlinear circuit is disclosed, comprising a metasurface absorber as described above and a nonlinear lumped circuit, wherein the nonlinear lumped circuit is connected to the lumped port of the metasurface absorber.

[0014] According to an aspect of this application, an exemplary metasurface absorber array is disclosed, comprising n*m metasurface absorbers as described above, wherein n and m are equal or unequal positive integers, each m of the metasurface absorbers is arranged in a row in a manner in which the lumped ports of the metasurface absorbers are arranged in parallel, thereby the n*m ​​metasurface absorbers are arranged in n rows, and each of the metasurface absorbers is connected to a nonlinear lumped circuit.

[0015] In some embodiments, the nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, a capacitor, and a first resistor. The anode of the first diode is connected to the anode of the second diode, the cathode of the third diode is connected to the cathode of the fourth diode, one end of the capacitor and the first resistor connected in parallel is connected between the first diode and the second diode, and the other end of the capacitor and the first resistor connected in parallel is connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

[0016] In some embodiments, the nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, an inductor, and a second resistor. The anode of the first diode is connected to the anode of the second diode, the cathode of the third diode is connected to the cathode of the fourth diode, one end of the series-connected inductor and second resistor is connected between the first diode and the second diode, and the other end of the series-connected inductor and second resistor is connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

[0017] The beneficial effects of this application are as follows: by providing a lumped port on the second metal sheet, the second metal sheet is divided into two sub-metal sheets symmetrically arranged about the lumped port, and rectangular slots are provided on the sub-metal sheets, a metasurface absorber with dual-frequency waveform selection is realized, which has the characteristics of small frequency ratio.

[0018] These and other objectives of this application will undoubtedly be apparent to those skilled in the art after reading the following detailed description of the figures and the preferred embodiments illustrated therein. Attached Figure Description

[0019] Figure 1a This is a three-dimensional structural schematic diagram of a metasurface absorber according to an embodiment of this application.

[0020] Figure 1b This is a top view of a metasurface absorber according to an embodiment of this application.

[0021] Figure 1c This is a bottom view of the metasurface absorber according to an embodiment of this application.

[0022] Figure 2 This is a simulated scattering parameter curve of a metasurface absorber according to an embodiment of this application.

[0023] Figure 3 This is a schematic diagram of the structure of a nonlinear circuit according to an embodiment of this application.

[0024] Figure 4 This is a circuit diagram of a nonlinear lumped circuit in a nonlinear circuit according to an embodiment of this application.

[0025] Figure 5 yes Figure 4 The absorption characteristic curve of the metasurface absorber when the nonlinear circuit is working.

[0026] Figure 6 This is a circuit diagram of another nonlinear lumped circuit in a nonlinear circuit according to an embodiment of this application.

[0027] Figure 7 yes Figure 6 The absorption characteristic curve of the metasurface absorber when the nonlinear circuit is working.

[0028] Figure 8 This is a schematic diagram of the structure of a metasurface absorber array according to an embodiment of this application. Detailed Implementation

[0029] Throughout this specification and claims, certain terms refer to specific components. As will be understood by those skilled in the art, electronic device manufacturers may use different names to refer to the same component. Components are distinguished not by name, but by function. In the following specification and claims, the term "comprising" is an open-ended limiting term and should therefore be interpreted as meaning "including but not limited to...". Furthermore, the term "coupled" is intended to mean either an indirect electrical connection or a direct electrical connection. Therefore, when one device is coupled to another device, this connection can be a direct electrical connection or an indirect electrical connection achieved through other devices and connecting parts.

[0030] like Figures 1a-1c The diagram shown is a structural schematic of a metasurface absorber 100 according to an embodiment of this application. The metasurface absorber 100 includes a dielectric substrate 110, on which a first metal sheet 120 and a second metal sheet 130 are disposed.

[0031] The dielectric substrate 110 can be Rogers 3010, with a relative permittivity εr of 10.2, a loss tangent of 0.0035, and a thickness of 1 mm. The first metal sheet 120 and the second metal sheet 130 can be copper sheets or copper layers, with a thickness of 17 μm and a conductivity that varies with frequency as σ = 5.8 × 10⁻⁶. 7 S / m.

[0032] A first metal sheet 120 is disposed on the first surface of the dielectric substrate 110, and the edges 120a-120d of the first metal sheet 120 coincide with the edges 110a-110d of the first surface of the dielectric substrate 110. The first metal sheet 120 is a ground plane and is in contact with the ground.

[0033] The second metal sheet 130 is disposed on the second surface of the dielectric substrate 110, wherein the second surface is disposed opposite to the first surface. For example, the first surface of the dielectric substrate 110 is the upper surface of the dielectric substrate 110, and the second surface of the dielectric substrate 110 is the lower surface of the dielectric substrate 110.

[0034] The two opposing edges 130a and 130b of the second metal sheet 130 do not coincide with the corresponding edges of the second surface, while the remaining edges of the second metal sheet 130 coincide with the remaining edges of the second surface. For example, the two opposing edges 130a are the upper edges of the second metal sheet 130, and edge 130b is the lower edge of the second metal sheet 130. Edge 130a of the second metal sheet 130 does not coincide with the edge 110a of the second surface of the dielectric substrate 110, edge 130b of the second metal sheet 130 does not coincide with the edge 110b of the second surface of the dielectric substrate 110, edge 130c of the second metal sheet 130 coincides with the edge 110c of the second surface of the dielectric substrate 110, and edge 130d of the second metal sheet 130 coincides with the edge 110d of the second surface of the dielectric substrate 110. It should be noted that in Figures 1a-1c In this context, the edges 110a-110d of the first surface of the dielectric substrate 110 and the edges 110a-110d of the second surface of the dielectric substrate 110 can be considered to be the same, both referring to the edges 110a-110d of the dielectric substrate 110, because the edges 110a-110d of the first surface and the edges 110a-110d of the second surface both refer to the same side of the dielectric substrate 110.

[0035] The second metal sheet 130 is provided with a lumped port p, which divides the second metal sheet 130 into two sub-metal sheets 131 and 132 symmetrically arranged about the lumped port p. The lumped port p extends from one edge 130a or 130b to the other edge 130b or 130a. That is, the second metal sheet 130 is divided into sub-metal sheets 131 and 132, and the lumped port p extends from edge 130a to edge 130b, or from edge 130b to edge 130a, i.e., the lumped port p penetrates through the second metal sheet 130. The sub-metal sheets 131 and 132 are symmetrically arranged about the lumped port p, meaning that the sub-metal sheets 131 and 132 are identical and are symmetrically arranged about the center line of the lumped port p in a symmetrical direction.

[0036] Each sub-metal piece 131 or 132 is provided with a rectangular slot g1 or g2, wherein the two rectangular slots g1 and g2 on the two sub-metal pieces 131 and 132 are symmetrically arranged about the lumped port p.

[0037] When the metasurface absorber 100 is excited, the second metal patch 130 generates a first resonant frequency and a second resonant frequency. The rectangular grooves g1 and g2 are used to change the electric field distribution of the second resonant frequency and increase the current flow path of the second resonant frequency to reduce the second resonant frequency, achieve a small frequency ratio, adjust the frequency, and increase design flexibility.

[0038] It should be noted that, Figures 1a-1c The second metal sheet 130 is a square metal sheet. Of course, the second metal sheet 130 can also be a metal sheet of other shapes, such as a rectangular metal sheet. This application only describes a square metal sheet as an example, but this application is not limited to this.

[0039] In this embodiment, a lumped port p is provided on the second metal sheet 130, so that the second metal sheet 130 is divided into two sub-metal sheets 131 and 132 symmetrically arranged about the lumped port p, and rectangular slots g1 and g2 are provided on the sub-metal sheets 131 and 132, realizing a metasurface absorber with dual-frequency waveform selection and having the characteristic of small frequency ratio.

[0040] In some embodiments, such as Figures 1a-1b As shown, a port groove 133 is provided on the second metal sheet 130 to serve as a lumped port p. The port groove 133 extends from one edge 130a or 130b of two oppositely arranged edges 130a and 130b to the other edge 130b or 130a.

[0041] In other words, the lumped port p is implemented through a port slot 133 provided on the second metal plate 130. The port slot 133 can be rectangular in shape.

[0042] In some embodiments, such as Figures 1a-1b As shown, the length directions of rectangular slots g1 and g2 are consistent with the extension direction of port slot 133, and the widths of rectangular slots g1 and g2 are smaller than the width of port slot 133.

[0043] The length directions of rectangular slots g1 and g2 are consistent with the extension direction of port slot 133, that is, rectangular slots g1 and g2 are arranged parallel to port slot 133. The wider the rectangular slots g1 and g2, the lower the second resonant frequency of the metasurface absorber 100, but the greater the impact on the overall energy distribution of the metasurface of the metasurface absorber 100, resulting in a worse reflection coefficient at the first and second resonant frequencies. Therefore, considering the overall performance of the metasurface absorber 100, the width of rectangular slots g1 and g2 is a preset value.

[0044] In some embodiments, such as Figures 1a-1b As shown, the two ends of rectangular grooves g1 and g2 are equidistant from the corresponding edges of the two edges 130a and 130b in the length direction.

[0045] Along the length direction, since rectangular slots g1 and g2 are symmetrically arranged about port slot 133, the distance from rectangular slot g1 to edge 130a is the same as the distance from rectangular slot g2 to edge 130a, and the distance from rectangular slot g1 to edge 130b is the same as the distance from rectangular slot g2 to edge 130b. Simultaneously, the distances from rectangular slot g1 to edge 130a and edge 130b are the same, and the distances from rectangular slot g2 to edge 130a and edge 130b are also the same.

[0046] In some embodiments, such as Figures 1a-1b As shown, the distance between rectangular slots g1 and g2 and port slot 133 is a preset value.

[0047] Since rectangular slots g1 and g2 are symmetrically arranged about port slot 133, the distance between rectangular slot g1 and port slot 133 is the same as the distance between rectangular slot g2 and port slot 133, both being preset values. The distance between rectangular slot g1 and port slot 133 and the distance between rectangular slot g2 and port slot 133 affect the energy distribution of the entire metasurface of the metasurface absorber 100, thereby affecting the reflection coefficients at the first and second resonant frequencies. When the distance between rectangular slot g1 and port slot 133 and the distance between rectangular slot g2 and port slot 133 increases, the impact on the energy distribution of the entire metasurface of the metasurface absorber 100 increases, resulting in a worse reflection coefficient at the first and second resonant frequencies. At the same time, when the distance between rectangular slot g1 and port slot 133 and the distance between rectangular slot g2 and port slot 133 decreases, the impact on the energy distribution of the entire metasurface of the metasurface absorber 100 also increases, resulting in a worse reflection coefficient at the first and second resonant frequencies. Therefore, considering the overall performance of the metasurface absorber 100, the distance between rectangular groove g1 and port groove 133 and the distance between rectangular groove g2 and port groove 133 are both preset values.

[0048] In some embodiments, such as Figures 1a-1c As shown, the two edges 130a and 130b of the second metal sheet 130 are at the same distance from the corresponding edges of the second surface of the dielectric substrate 110.

[0049] The distance between the edge 130a of the second metal sheet 130 and the corresponding edge 110a of the second surface of the dielectric substrate 110 is the same as the distance between the edge 130b of the second metal sheet 130 and the corresponding edge 110b of the second surface of the dielectric substrate 110. That is, if the distance between the edge 130a of the second metal sheet 130 and the edge 110a of the dielectric substrate 110 is denoted as x mm, then the distance between the edge 130b of the second metal sheet 130 and the edge 110b of the dielectric substrate 110 is also x mm.

[0050] like Figure 2 The figure shown is a simulated scattering parameter curve of the metasurface absorber 100 according to an embodiment of this application. For the metasurface absorber 100 of the above embodiment, when it is fabricated using Rogers 3010, the S-parameters at both resonant frequencies are less than -10dB, indicating that its reflection coefficient is only 0.1. This means that 10% of the input signal power is reflected back, and 90% of the signal power is transmitted or absorbed. It has low signal loss, good transmission performance, and strong waveform selective absorption capability.

[0051] like Figure 3 The diagram shown is a schematic representation of a nonlinear circuit according to an embodiment of this application. The nonlinear circuit includes a metasurface absorber 210 and a nonlinear lumped circuit 220, wherein the nonlinear lumped circuit 220 is connected to the lumped port p of the metasurface absorber 210.

[0052] The metasurface absorber 210 can be the metasurface absorber 100 of the above embodiment, as detailed in the description of the above embodiment. The metasurface absorber 210 transfers energy to the nonlinear lumped circuit 220, thereby selectively absorbing continuous and pulsed waves.

[0053] In some embodiments, such as Figure 4 As shown, the nonlinear lumped circuit 220 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, a capacitor C, and a first resistor R1. The anode of the first diode D1 is connected to the anode of the second diode D2, and the cathode of the third diode D3 is connected to the cathode of the fourth diode D4. One end of the parallel capacitor C and the first resistor R1 is connected between the first diode D1 and the second diode D2, and the other end of the parallel capacitor C and the first resistor R1 is connected between the third diode D3 and the fourth diode D4. The cathodes of the first diode D1, the cathodes of the second diode D2, the anodes of the third diode D3, and the anodes of the fourth diode D4 are connected to the lumped port p.

[0054] The first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 can be Schottky diodes, used to form a bridge rectifier circuit to convert the input wave signal into a zero-frequency component. The capacitor C can be 1nF, and the first resistor can be 10kΩ.

[0055] When the nonlinear circuit 200 is working, the parallel capacitor C can temporarily store the rectified electromagnetic energy. The pulse wave gradually charges it, and during the pulse interval, capacitor C discharges, and current flows through the first resistor R1. The current energy is dissipated by the heat effect of the first resistor R1. After the continuous wave continues to charge, capacitor C is fully charged, at which point the circuit is broken, and current cannot flow into the nonlinear lumped circuit 220. Therefore, the metasurface absorber 210 can absorb pulse waves more effectively, but its absorption effect on continuous waves of the same frequency is poor. Figure 5 As shown, at frequencies of around 1.8 GHz and 3.9 GHz, the metasurface absorber 210 achieves an absorption rate of about 80% for pulsed waves, which far exceeds the absorption rate for continuous waves.

[0056] In other embodiments, such as Figure 6 As shown, the nonlinear lumped circuit 220 includes a first diode D1, a second diode D2, a third diode D3, a fourth diode D4, an inductor L, and a second resistor R2. The anode of the first diode D1 is connected to the anode of the second diode D2, and the cathode of the third diode D3 is connected to the cathode of the fourth diode D4. One end of the series-connected inductor L and second resistor R2 is connected between the first diode D1 and the second diode D2, and the other end of the series-connected inductor L and second resistor R2 is connected between the third diode D3 and the fourth diode D4. The cathodes of the first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 are connected to the lumped port p.

[0057] The first diode D1, the second diode D2, the third diode D3, and the fourth diode D4 can be Schottky diodes, used to form a bridge rectifier circuit to convert the input wave signal into a zero-frequency component. The inductor L can be 100μH, and the resistance of the second resistor can be 5.5Ω.

[0058] When the nonlinear circuit 200 is working, after the continuous wave fully charges the inductor L, the inductor L is short-circuited, and the energy of the current is consumed by the second resistor R2. The pulse wave, due to the induced voltage in the inductor L, cannot flow into the nonlinear lumped circuit 220. Therefore, the metasurface absorber 210 can absorb continuous waves well, but its absorption effect on pulse waves of the same frequency is poor, such as... Figure 7 As shown, at frequencies of around 1.8 GHz and 3.9 GHz, the metasurface absorber 210 achieves an absorption rate of approximately 90% for continuous waves, far exceeding its absorption rate for pulsed waves.

[0059] like Figure 8 The diagram shown is a schematic representation of a metasurface absorber array according to an embodiment of this application. The metasurface absorber array 300 includes n*m metasurface absorbers 310, where n and m are equal or unequal positive integers. Each set of m metasurface absorbers 310 is arranged in a row with their lumped ports arranged in parallel, resulting in n*m metasurface absorbers 310 arranged in n rows. Each metasurface absorber 310 is connected to a nonlinear lumped circuit (not shown in the diagram).

[0060] The metasurface absorber 310 can be the metasurface absorber 100 of the above embodiments, as detailed in the description of the above embodiments. The nonlinear lumped circuit can also be detailed in the description of the above embodiments, for example, the above... Figure 4 Description of the embodiments.

[0061] n and m can be equal or unequal positive integers, determined by the application scenario. For example, for 3*3 metasurface absorbers 310, n = m = 3. Or, for 8*16 metasurface absorbers 310, n = 8 and m = 16.

[0062] Those skilled in the art will readily recognize that numerous modifications and variations can be made to the apparatus and method while maintaining the teachings of this application. Therefore, the above disclosure should be considered limited only by the scope of the appended claims.

Claims

1. A supersurface absorber, characterized in that, Includes a dielectric substrate, wherein the dielectric substrate is provided with: A first metal sheet is disposed on a first surface of the dielectric substrate, and the edge of the first metal sheet coincides with the edge of the first surface. A second metal sheet is disposed on a second surface of the dielectric substrate, wherein the second surface is disposed opposite to the first surface, two opposite edges of the second metal sheet do not coincide with the corresponding edges of the second surface, and the remaining edges of the second metal sheet coincide with the remaining edges of the second surface; The second metal sheet is provided with a lumped port, such that the second metal sheet is divided into two sub-metal sheets symmetrically arranged about the lumped port, and the lumped port extends from one edge of the two oppositely arranged edges to the other edge; Each of the sub-metal plates is provided with a rectangular slot, wherein the two rectangular slots on the two sub-metal plates are symmetrically arranged about the lumped port; The second metal sheet is provided with a port slot to serve as the lumped port, the port slot extending from one of the two opposing edges to the other edge; The length direction of the rectangular groove is consistent with the extension direction of the port groove, and the width of the rectangular groove is smaller than the width of the port groove; When the metasurface absorber is excited, the second metal sheet generates a first resonant frequency and a second resonant frequency. The two rectangular slots are used to change the electric field distribution at the second resonant frequency and increase the current flow path at the second resonant frequency.

2. The supersurface absorber as described in claim 1, characterized in that, The two ends of the rectangular groove are equidistant from the corresponding edges of the two edges along the length direction.

3. The supersurface absorber as described in claim 1, characterized in that, The distance between the rectangular slot and the port slot is a preset value.

4. The supersurface absorber as described in claim 1, characterized in that, The two edges are at the same distance from the corresponding edges of the second surface.

5. A nonlinear circuit, characterized in that, It includes a metasurface absorber as described in any one of claims 1-4 and a nonlinear lumped circuit, wherein the nonlinear lumped circuit is connected to the lumped port of the metasurface absorber.

6. The nonlinear circuit as described in claim 5, characterized in that, The nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, a capacitor, and a first resistor. The anode of the first diode is connected to the anode of the second diode, and the cathode of the third diode is connected to the cathode of the fourth diode. One end of the capacitor and the first resistor, which are connected in parallel, is connected between the first diode and the second diode, and the other end of the capacitor and the first resistor is connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

7. The nonlinear circuit as described in claim 5, characterized in that, The nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, an inductor, and a second resistor. The anode of the first diode is connected to the anode of the second diode, and the cathode of the third diode is connected to the cathode of the fourth diode. One end of the inductor and the second resistor, which are connected in series, is connected between the first diode and the second diode, and the other end of the inductor and the second resistor, which are connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

8. A metasurface absorber array, characterized in that, It includes n*m metasurface absorbers as described in any one of claims 1-4, wherein n and m are equal or unequal positive integers, each m metasurface absorbers are arranged in a row in a parallel manner according to the lumped ports of the metasurface absorbers, so that the n*m ​​metasurface absorbers are arranged in n rows, and each metasurface absorber is connected to a nonlinear lumped circuit.

9. The supersurface absorber array as described in claim 8, characterized in that, The nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, a capacitor, and a first resistor. The anode of the first diode is connected to the anode of the second diode, and the cathode of the third diode is connected to the cathode of the fourth diode. One end of the capacitor and the first resistor, which are connected in parallel, is connected between the first diode and the second diode, and the other end of the capacitor and the first resistor is connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

10. The metasurface absorber array as described in claim 8, characterized in that, The nonlinear lumped circuit includes a first diode, a second diode, a third diode, a fourth diode, an inductor, and a second resistor. The anode of the first diode is connected to the anode of the second diode, and the cathode of the third diode is connected to the cathode of the fourth diode. One end of the inductor and the second resistor, which are connected in series, is connected between the first diode and the second diode, and the other end of the inductor and the second resistor, which are connected between the third diode and the fourth diode. The cathodes of the first diode, the second diode, the third diode, and the fourth diode are connected to the lumped port.

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