Dual polarized c-band energy selective surface

Abstract

This invention relates to a dual-polarized C-band energy selective surface, comprising a dielectric layer and a structural layer disposed on the dielectric layer; the structural layer includes a metal frame, an induction region, and a resonant region disposed on the same plane from the outside in; wherein, there is a gap between the metal frame and the induction region; the induction region includes four L-shaped induction strips disposed circumferentially, the long arms of the L-shaped induction strips being respectively along the horizontal and vertical directions; horizontal nonlinear devices are disposed at the horizontal intervals of the L-shaped induction strips, and vertical nonlinear devices are disposed at the vertical intervals of the L-shaped induction strips; the L-shaped induction strips are electrically connected by the horizontal and vertical nonlinear devices; in the resonant region, four binary encoding matrices are disposed in a quadrant distribution, and the binary encoding matrices are encoded to independently control the response characteristics of TE-polarized and TM-polarized electromagnetic waves. This invention enables dual-polarization control while simultaneously achieving low insertion loss and high shielding effectiveness.

Description

Technical Field

[0001] This invention relates to the field of electromagnetic protection technology, and in particular to a dual-polarized C-band energy selective surface. Background Technology

[0002] Energy Selective Surface (ESS), as a novel adaptive electromagnetic protection technology, has significant application value in the field of electromagnetic protection. Its core function lies in its ability to adaptively switch its operating state according to changes in the external electromagnetic environment. During normal operation, it remains transparent to the signals to be transmitted, exhibiting low insertion loss (IL) characteristics to ensure the stability and effectiveness of signal transmission. When encountering strong electromagnetic attacks, it can automatically switch to a shielded state, possessing high shielding effectiveness (SE), thereby providing reliable electromagnetic protection for the equipment and preventing strong electromagnetic signals from interfering with or damaging the normal operation of the equipment.

[0003] Most existing energy selective surface (ESS) designs employ fixed topologies, such as cross-shaped and square-ring-shaped structures. These designs often rely heavily on parameter scanning techniques and the designer's experience during performance optimization, resulting in limited optimization space and inherent limitations in practical applications, making it difficult to meet increasingly complex electromagnetic protection requirements. Specifically, at the structural design level, achieving high-performance electromagnetic protection requires coordinating two different resonant modes within a single topology, which is challenging and limits optimization space. At the performance level, while simple single-resonant structures are easy to implement, they often struggle to balance low insertion loss (IL) and high shielding effectiveness (SE), and have limited bandwidth. At the design efficiency level, traditional designs rely on full-wave electromagnetic simulation, which is time-consuming for each performance evaluation, severely limiting the feasibility of global optimization across a broad design space. At the manufacturing adaptation level, some complex topologies designed for high performance require multilayer board processing or special manufacturing processes, significantly increasing manufacturing costs and potentially reducing product reliability due to increased process complexity, hindering large-scale production and practical application. Summary of the Invention

[0004] Therefore, it is necessary to provide a dual-polarized C-band energy selective surface that can achieve high performance and is easy to design and manufacture, in order to address the above-mentioned technical problems.

[0005] A dual-polarized C-band energy selective surface includes a dielectric layer, on which a structural layer is disposed;

[0006] The structural layer includes a metal frame, a sensing area, and a resonant area arranged on the same plane from the outside to the inside; wherein, there is a gap between the metal frame and the sensing area;

[0007] The sensing area includes four L-shaped sensing strips arranged circumferentially, with the long arms of the L-shaped sensing strips arranged along the horizontal and vertical directions, respectively.

[0008] Horizontal nonlinear devices are provided at the horizontal intervals of the L-shaped sensing strips, and vertical nonlinear devices are provided at the vertical intervals of the L-shaped sensing strips; the L-shaped sensing strips are electrically connected through the horizontal and vertical nonlinear devices.

[0009] In the resonant region, four binary encoding matrices are arranged in a quadrant distribution. These binary encoding matrices are encoded to independently control the response characteristics of TE-polarized and TM-polarized electromagnetic waves.

[0010] In one embodiment, the four binary encoding matrices are arranged in a centrally rotationally symmetric manner.

[0011] In one embodiment, four L-shaped sensing strips correspond to the positions of four binary encoding matrices respectively; the L-shaped sensing strips are located on the periphery of the binary encoding matrices, and the inner angles of the L-shaped sensing strips face the binary encoding matrices.

[0012] In one embodiment, the lengths of the two long arms of the L-shaped sensing strip are matched with the length and width of the binary encoding matrix, respectively.

[0013] In one embodiment, the binary encoding matrix is ​​encoded by setting metal patches.

[0014] In one embodiment, the binary encoding matrix is ​​a square matrix of order greater than or equal to 4.

[0015] In one embodiment, the metal patch is square, with a side length ranging from 1.050 mm to 1.225 mm.

[0016] In one embodiment, the horizontal nonlinear device and the vertical nonlinear device are Schottky diodes or PIN diodes.

[0017] In one embodiment, the dielectric constant of the dielectric layer is 4.4 and the thickness is 0.508 mm.

[0018] In one embodiment, the width of the L-shaped sensing strip ranges from 0.4 mm to 0.8 mm.

[0019] Compared with existing technologies, the dual-polarized C-band energy selective surface provided by this invention has the following beneficial effects:

[0020] 1. A single-layer structure is constructed by setting a metal frame, sensing area, and resonant area on the same plane from the outside to the inside. Then, two sets of orthogonal structures are constructed in the horizontal and vertical directions by using L-shaped sensing strips. Nonlinear devices are set in the horizontal and vertical directions to realize the electrical connection between the L-shaped sensing strips. This achieves the dual-polarization design of the single-layer structure and allows the nonlinear devices to switch states according to the energy intensity of different polarization waves, providing support for adaptive energy screening in dual-polarization scenarios.

[0021] 2. By adjusting the length and width of the long arm of the L-shaped induction strip, a basic impedance network covering multiple frequency points can be constructed in the C-band, providing a suitable impedance environment for the binary coding matrix of the resonant region. The four binary coding matrices of the resonant region are distributed in quadrants, which can accurately match the target frequency impedance in their respective polarization directions, so that the energy selective surface can simultaneously achieve low insertion loss and high shielding effectiveness in a wide frequency range, resulting in strong protection capabilities.

[0022] 3. In the resonant region, binary coding is used to directly parameterize the entire resonant region, transforming the complex physical structure design problem into an intuitive coding optimization problem. This simplifies the design and optimization of the energy selection surface, greatly reducing the design threshold and cycle time. During design optimization, the equivalent circuit parameters can be intuitively adjusted by changing the coding, which not only enables precise performance control and high flexibility, but also allows for the coverage of more frequency points through multiple coding combinations, achieving an ultra-wide operating bandwidth.

[0023] 4. The structural layer is a single layer with single-sided wiring. All metal patterns can be made in a single standard PCB etching process. Then, nonlinear devices can be soldered using surface mount technology. The structure is simple, low-cost, and has good consistency. It effectively avoids the production errors caused by multi-layer structures and is very suitable for mass production. Attached Figure Description

[0024] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings required in the embodiments will be briefly described below. It should be understood that the following drawings only show some embodiments of the present invention, and those skilled in the art can obtain other related drawings based on these drawings without creative effort.

[0025] Figure 1 A schematic diagram of a first type of dual-polarized C-band energy-selective surface structure provided in one embodiment;

[0026] Figure 2 A comparison chart of transmission coefficient curves under the first structure provided in one embodiment;

[0027] Figure 3 A schematic diagram of a second type of dual-polarized C-band energy-selective surface structure provided in one embodiment;

[0028] Figure 4 A comparison diagram of transmission coefficient curves under the second structure provided in one embodiment;

[0029] Figure 5 A schematic diagram of a third type of dual-polarized C-band energy-selective surface structure provided in one embodiment;

[0030] Figure 6 A comparison chart of transmission coefficient curves under the third structure provided in one embodiment;

[0031] Figure 7 A schematic diagram of a fourth type of dual-polarized C-band energy-selective surface structure provided in one embodiment;

[0032] Figure 8 This is a comparison chart of the transmission coefficient curves under the fourth structure provided in one embodiment.

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Dielectric layer; 2. Structural layer; 3. Metal frame; 4. L-shaped sensing strip; 5. Horizontal nonlinear device; 6. Vertical nonlinear device; 7. Binary encoding matrix; 8. Metal patch.

[0035] The objectives, features, and advantages of this invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0036] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0037] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0038] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0039] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection, an electrical connection, a physical connection, or a wireless communication connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two elements or the interaction between two elements, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0040] It is understood that the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0041] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0042] like Figure 1 As shown, a first type of dual-polarized C-band energy selective surface is provided, including a dielectric layer 1 and a structural layer 2 disposed on the dielectric layer 1; the structural layer 2 includes a metal frame 3, an induction region and a resonant region disposed on the same plane from the outside to the inside; wherein, there is a gap between the metal frame 3 and the induction region.

[0043] The sensing area includes four L-shaped sensing strips 4 arranged in a circumferential pattern, with the long arms of the L-shaped sensing strips 4 arranged along the horizontal and vertical directions, respectively. Horizontal nonlinear devices 5 are arranged at the horizontal intervals of the L-shaped sensing strips 4, and vertical nonlinear devices 6 are arranged at the vertical intervals of the L-shaped sensing strips 4. Each L-shaped sensing strip 4 is electrically connected through the horizontal nonlinear devices 5 and the vertical nonlinear devices 6. In the resonant area, four binary encoding matrices 7 are arranged in a quadrant distribution. The binary encoding matrices 7 are encoded to independently control the response characteristics of TE polarized and TM polarized electromagnetic waves.

[0044] Specifically, the dielectric layer 1 serves as the basic carrier and is made of a substrate material with a dielectric constant of 4.4, a loss tangent of 0.001, and a thickness of 0.508 mm. Preferably, it is made of F4B substrate.

[0045] A structural layer 2 is disposed on the upper surface of the dielectric layer 1, and the thickness of the structural layer 2 is preferably 0.035mm. The structural layer 2 adopts a single-layer single-sided wiring design, and all metal structures are located on the same plane. From the outside to the inside, it is divided into a metal frame 3, a sensing area, and a resonant area. A certain gap is reserved between the metal frame 3 and the sensing area, with a gap width of 0.2mm~0.4mm, to avoid unnecessary electromagnetic interference between the two and ensure that each functional area can work independently and collaboratively.

[0046] The metal frame 3, serving as the outer structure of structural layer 2, is a continuous closed metal ring of width s. Its primary function is to construct the electromagnetic boundary and provide mechanical support. It effectively filters out low-frequency electromagnetic waves, laying the foundation for the precise processing of C-band electromagnetic waves in the subsequent induction and resonant regions. The metal frame 3 is square, with a preferred side length of 12mm; the width of the metal ring ranges from [value missing]. s =0.1mm~0.3mm, preferably 0.2mm.

[0047] The sensing area is located between the metal frame 3 and the resonant area, and consists of four L-shaped sensing strips 4. The four L-shaped sensing strips 4 are arranged in a circumferential interval, and the interval ranges from [value missing]. g =0.4mm~1.0mm, preferably 0.8mm; the long arms of each L-shaped sensing strip 4 are arranged along the horizontal and vertical directions respectively, forming two sets of orthogonal sensing structures. A horizontal nonlinear device 5 is installed at the horizontal interval of adjacent L-shaped sensing strips 4, and a vertical nonlinear device 6 is installed at the vertical interval. The nonlinear devices are electrically connected to the L-shaped sensing strips 4 by welding, so that the four L-shaped sensing strips 4 form a complete sensing circuit. The width of the L-shaped sensing strip 4 is set within the range of... sw =0.4mm~0.8mm, preferably 0.6mm; the lengths of its two long arms are matched with the length and width of the binary coding matrix 7 in the resonant region, respectively. Through this size design, a basic impedance network covering multiple frequency points can be constructed in the C-band, providing support for impedance matching in the resonant region. The horizontal nonlinear device 5 and the vertical nonlinear device 6 adopt Schottky diodes (NSR201) or PIN diodes (SMP1345), preferably Schottky diodes.

[0048] The resonant region is located at the center of structural layer 2, and four binary encoding matrices 7 are arranged in a quadrant-like pattern. These four matrices 7 are arranged with central rotational symmetry, and each matrix corresponds to an L-shaped induction strip 4. The L-shaped induction strip 4 is located on the periphery of the binary encoding matrix 7, with its interior angles pointing towards the binary encoding matrix 7. This positional relationship ensures the electromagnetic coupling efficiency between the induction region and the resonant region. Each binary encoding matrix 7 is a 4×4 matrix structure. Each bit in the binary encoding matrix 7 corresponds to a physical unit, which is binary encoded using metal patches 8. A "1" represents the placement of a square metal patch 8 in the corresponding physical unit. The side length of the metal patch 8 ranges from [value missing]. pm =1.050mm~1.225mm, preferably 1.125mm; "0" represents the physical unit position as a dielectric region. By using different encoding combinations of the four binary encoding matrices 7, the entire resonant region can be directly parameterized, transforming the complex physical structure design into intuitive encoding optimization. This not only allows for independent control of the response characteristics of TE-polarized and TM-polarized electromagnetic waves, but also enables precise control of the energy-selective surface performance by rapidly adjusting the equivalent circuit parameters during the design optimization process through changing the encoding. It is worth noting that the metal patch 8 has no electrical connection to the surrounding metal frame 3.

[0049] In this embodiment, the L-shaped sensing strip 4 is made of metal. Furthermore, the metal frame 3, the L-shaped sensing strip 4, and the metal patch 8 are preferably made of copper and have an anti-oxidation layer plated on their surfaces.

[0050] During manufacturing, since structural layer 2 is a single-layer, single-sided wiring, the metal frame 3, L-shaped sensing strip 4, and metal patch 8 in the binary encoding matrix 7 can be fabricated through a single standard PCB etching process. Subsequently, surface mount technology is used to solder the nonlinear devices to their designated positions. The entire production process eliminates the need for complex multi-layer processing steps, reducing production difficulty and cost while effectively ensuring product consistency and avoiding production errors caused by multi-layer structures, making it ideal for large-scale mass production. Furthermore, when the performance of the energy selection surface needs to be adjusted to suit different application scenarios, there is no need to redesign the overall structure. Simply changing the encoding method of the binary encoding matrix 7 in the resonant region allows for adjustments to parameters such as operating frequency, insertion loss, and protection performance, significantly shortening the design cycle and lowering the design threshold. This provides a flexible and efficient solution for adaptive energy screening in C-band dual-polarization scenarios.

[0051] During operation, when low-power C-band electromagnetic waves irradiate the energy selective surface, the nonlinear device in the sensing area is in the off state. At this time, the nonlinear device is equivalent to a capacitor, and the entire energy selective surface structure is in an unprotected state. Electromagnetic waves can pass smoothly through dielectric layer 1 and structural layer 2, exhibiting good wave transmission characteristics. However, when a strong electromagnetic signal is incident, the L-shaped sensing strip 4 in the sensing area senses that the spatial electromagnetic field intensity reaches the threshold, and the nonlinear device will be turned on instantaneously. At this time, the nonlinear device is equivalent to a resistor, and the energy selective surface structure switches to a protected state.

[0052] In the protected state, the high-pass filtering effect of the metal frame 3, the induction circuit formed by the L-shaped induction strip 4 in the induction zone, and the multiple resonant circuits constructed by the binary coding matrix 7 in the resonant zone work together to achieve efficient shielding of electromagnetic waves in the C-band. Furthermore, by adjusting the length and width of the long arm of the L-shaped induction strip 4, combined with different coding combinations of the binary coding matrix 7 in the resonant zone, the energy selective surface can maintain excellent protection and efficient wave transmission within a wide frequency range of 4-6 GHz, thus broadening its applicability.

[0053] Tests showed that the average insertion loss in this frequency band is less than 0.4dB, the highest protection performance is close to 40dB, the -10dB bandwidth is greater than 1GHz, and it can achieve the best protection effect at different frequency points for TE polarized and TM polarized electromagnetic waves.

[0054] In this embodiment, binary encoding matrix 7 is encoded in different forms to demonstrate the optimal protection effect achieved at different frequency points:

[0055] like Figure 1 As shown, this is the first encoding format. Under this encoding format, the result is as follows: Figure 2 The transmission coefficient curves shown in the diagram indicate that for TE-polarized electromagnetic waves, the maximum protection efficiency is approximately 38.94 dB at 4.625 GHz; for TM-polarized electromagnetic waves, the maximum protection efficiency is approximately 38.82 dB at 4.708 GHz.

[0056] like Figure 3 As shown, this is the second encoding format. Under this encoding format, the result is as follows: Figure 4 The transmission coefficient curves shown in the figure demonstrate that for TE-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 38.57 dB at 4.714 GHz; for TM-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 37.77 dB at 4.496 GHz.

[0057] like Figure 5 As shown, this is the third encoding format. Under this encoding format, the result is as follows: Figure 6The transmission coefficient curves shown in the diagram demonstrate that for TE-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 40.57 dB at 5.078 GHz; for TM-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 38.79 dB at 4.518 GHz.

[0058] like Figure 7 As shown, this is the fourth encoding format. Under this encoding format, the result is as follows: Figure 8 The transmission coefficient curves shown in the diagram demonstrate that, for TE-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 39.49 dB at 4.546 GHz; and for TM-polarized electromagnetic waves, the maximum protection efficiency reaches approximately 39.55 dB at 4.540 GHz.

[0059] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0060] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these modifications and improvements all fall within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the appended claims.

Claims

1. A dual-polarized C-band energy selective surface, characterized in that, The structure layer is arranged on a medium layer; The structure layer comprises a metal frame, an inductive region and a resonant region arranged in the same plane from outside to inside; The inductive region comprises four L-shaped inductive strips arranged in a ring shape, and long arms of the L-shaped inductive strips are arranged in a horizontal direction and a vertical direction, respectively; Horizontal nonlinear devices are arranged at intervals in the horizontal direction of the L-shaped inductive strips, and vertical nonlinear devices are arranged at intervals in the vertical direction of the L-shaped inductive strips; each L-shaped inductive strip is electrically connected through the horizontal nonlinear devices and the vertical nonlinear devices; the horizontal nonlinear devices and the vertical nonlinear devices are Schottky diodes or PIN diodes; In the resonant region, four binary coding matrices are arranged in a quadrant distribution manner, and the binary coding matrices are coded to independently control response characteristics of TE polarized and TM polarized electromagnetic waves; The four binary coding matrices are arranged in a central rotational symmetry manner; the four L-shaped inductive strips are respectively positioned corresponding to the four binary coding matrices; The L-shaped inductive strips are located at the periphery of the binary coding matrices, and inner angles of the L-shaped inductive strips face the binary coding matrices.

2. The dual-polarized C-band energy-selective surface of claim 1, wherein, Lengths of the two long arms of the L-shaped inductive strips are respectively matched with lengths and widths of the binary coding matrices.

3. The dual-polarized C-band energy-selective surface according to claim 1 or 2, characterized in that, In the binary coding matrix, the coding is performed in a manner of arranging metal patches.

4. The dual-polarized C-band energy-selective surface of claim 1 or 2, wherein, The binary coding matrix is a square matrix with an order greater than or equal to 4.

5. The dual-polarized C-band energy-selective surface of claim 3, wherein, The metal patch is a square with a side length in a range of 1.050 mm to 1.225 mm.

6. The dual-polarized C-band energy-selective surface of claim 1 or 2, wherein, The medium layer has a dielectric constant of 4.4 and a thickness of 0.508 mm.

7. The dual-polarized C-band energy-selective surface of claim 1 or 2, wherein, The L-shaped inductive strip has a width in a range of 0.4 mm to 0.8 mm.

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