Dual-band frequency selective surface structure with high resonance ratio and unit structure

Abstract

The application discloses a high-resonance-ratio double-stop-band frequency selective surface structure and a unit structure, belongs to the technical field of electromagnetic waves, and is characterized in that the structure comprises a metal layer and a dielectric substrate; a square ring patch and a rhombus ring combined patch are arranged on the metal layer; the center of the rhombus ring combined patch is coincident with the center of the metal layer; the rhombus ring combined patch is composed of rhombus ring patches which are sequentially arranged by rotating around the structure center by 45 degrees; and the square ring patch is arranged around the rhombus ring combined patch. The structure has small size, can meet the demand of miniaturization of devices, has very good polarization stability, has high-resonance-ratio characteristics when the first resonant frequency deviation is within an acceptable range when TE and TM polarized incident waves are irradiated, and has very good angle stability, has high-resonance-ratio characteristics when the first resonant frequency deviation is within an acceptable range when TE and TM modes are irradiated by incident waves at different angles.

Description

Technical Field

[0001] The present invention belongs to the technical field of electromagnetic waves, and in particular relates to a dual-stopband frequency selective surface structure and a unit structure with a high resonance ratio. Background Art

[0002] A frequency selective surface (FSS) is a passive, two-dimensional array of periodic structures that selectively affects electromagnetic waves. Based on its structural design, it can reflect or transmit electromagnetic waves of specific frequencies. FSS structures can be generally categorized as either patch or slot types. Patch types exhibit band-stop characteristics, while slot types exhibit band-pass characteristics. Due to their unique filtering properties, FSSs have become a hot topic of research and are widely used in antenna, metamaterial, and microwave device design.

[0003] The shortcomings of existing frequency selective surfaces are that their filtering frequency band is single and the filtering characteristics are poor, which cannot meet the requirements of more scenarios and higher performance. In addition, they cannot be adapted to dual-band devices with a larger frequency band span. This is mainly manifested in poor structural stability and the inability of structural design to achieve a high resonance ratio. In addition, the existing frequency selective surface structure unit size is large and the overall structure thickness is relatively high, which can no longer meet the current urgent demand for miniaturized structures. Summary of the Invention

[0004] In order to solve the above problems existing in the prior art, the present invention provides a dual-stopband frequency selective surface structure and unit structure with a high resonance ratio. The technical problem to be solved by the present invention is achieved through the following technical solutions:

[0005] In the first aspect, the present invention provides a dual-stopband frequency selective surface unit structure with a high resonance ratio, comprising a metal layer and a dielectric substrate arranged in sequence from top to bottom; a square ring patch and a diamond ring combination patch are arranged on the metal layer; the center of the diamond ring combination patch coincides with the center of the metal layer; the diamond ring combination patch is composed of diamond ring patches that are rotated 45° around the center of the structure; the square ring patch is arranged around the diamond ring combination patch.

[0006] Furthermore, in the high resonance ratio dual-stopband frequency selective surface unit structure of the present invention, the square ring patch and the diamond ring combination patch are both axially symmetrical structures and centrosymmetrical structures.

[0007] Furthermore, in the high resonance ratio dual-stopband frequency selective surface unit structure of the present invention, the diamond ring combination patch includes eight diamond ring patches.

[0008] Furthermore, in the dual-stopband frequency selective surface unit structure with a high resonance ratio of the present invention, the dielectric substrate is a square structure.

[0009] Furthermore, in the dual-stopband frequency selective surface unit structure with a high resonance ratio of the present invention, the metal layer coincides with the center of the dielectric substrate.

[0010] Furthermore, in the dual-stopband frequency selective surface unit structure with a high resonance ratio of the present invention, the dielectric substrate is made of a flame-resistant material; the metal layer is made of metal; and the metal includes copper, aluminum, or gold.

[0011] Furthermore, in the dual-stopband frequency selective surface unit structure with a high resonance ratio described in the present invention, the outer size of the metal layer is 7.9mm*7.9mm; the size of the dielectric substrate is 8mm*8mm, so as to meet the trend of miniaturization structure.

[0012] In a second aspect, the present invention provides a dual-stopband frequency selective surface structure with a high resonance ratio, comprising M×N periodically arranged frequency selective surface unit structures as described in any one of the first aspects, wherein M and N are integers greater than or equal to 1.

[0013] Compared with the prior art, the present invention has the following beneficial effects:

[0014] 1. The high resonance ratio dual-stopband frequency selective surface structure of the present invention is small in size. The surface size of its unit structure is only 8mm*8mm, which can meet the current demand for miniaturization of devices.

[0015] 2. The high resonance ratio dual-stopband frequency selective surface structure of the present invention has a dual-band band-stop characteristic, which can achieve a band-stop effect in the frequency bands of 2.33-6.31 GHz and 18.23-28.78 GHz at a depth of -10 dB.

[0016] 3. The high resonance ratio dual-stopband frequency selective surface structure of the present invention has resonant frequencies of 4.25 GHz and 25.32 GHz, a resonant frequency ratio of 5.96, and has a high resonance ratio characteristic.

[0017] 4. The high resonance ratio dual-stopband frequency selective surface structure of the present invention has very good polarization stability. When irradiated with TE and TM polarized incident waves, the resonance frequency deviation is within an acceptable range and always has a high resonance ratio characteristic.

[0018] 5. The high resonance ratio dual-stopband frequency selective surface structure described in the present invention has very good angular stability. In TE and TM modes, when incident waves are irradiated at different angles, the deviation of the first resonance frequency is within an acceptable range, and the deviation of the second resonance frequency is larger, but it always has a high resonance ratio characteristic. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 A three-dimensional diagram of a dual-stopband frequency selective surface unit structure according to an embodiment of the present invention;

[0020] Figure 2 A side view of a dual-stopband frequency selective surface unit structure according to an embodiment of the present invention;

[0021] Figure 3 This is a front view of the metal layer of the dual-stopband frequency selective surface unit structure according to an embodiment of the present invention;

[0022] Figure 4 This is a three-dimensional diagram of a dual-stopband frequency selective surface multi-unit structure according to an embodiment of the present invention;

[0023] Figure 5 This is a simulation diagram of the filtering performance of the dual-stopband frequency selective surface structure in the TE polarization mode according to an embodiment of the present invention;

[0024] Figure 6 This is a simulation diagram of the filtering performance of the dual-stopband frequency selective surface structure in the TM polarization mode according to an embodiment of the present invention;

[0025] Figure 7 This is a simulation diagram of the angular stability performance of the dual-stopband frequency selective surface structure in the TE polarization mode according to an embodiment of the present invention;

[0026] Figure 8 This is a simulation diagram of the angular stability performance of the dual-stopband frequency selective surface structure in the TM polarization mode according to an embodiment of the present invention;

[0027] Among them, 1 is a metal layer; 11 is a square ring patch; 12 is a diamond ring combination patch; 121 is a diamond ring patch; 2 is a dielectric substrate. DETAILED DESCRIPTION

[0028] In order to further illustrate the technical means and effects adopted by the present invention to achieve the predetermined purpose of the invention, the dual-stopband frequency selective surface with a high resonance ratio proposed in accordance with the present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0029] The aforementioned and other technical contents, features, and effects of the present invention are clearly presented in the following detailed description of the specific embodiments in conjunction with the accompanying drawings. Through the description of the specific embodiments, a deeper and more specific understanding of the technical means and effects adopted by the present invention to achieve the intended purpose can be obtained. However, the accompanying drawings are provided for reference and illustration purposes only and are not intended to limit the technical solutions of the present invention.

[0030] It should be noted that, in this document, the terms "comprises," "comprising," or any other variations thereof are intended to encompass non-exclusive inclusion, such that an article or device comprising a list of elements includes not only those elements but also other elements not explicitly listed. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of additional identical elements in the article or device comprising the element.

[0031] like Figure 1 、 Figure 2 、 Figure 3 As shown, the frequency selective surface unit structure of the embodiment of the present disclosure includes a metal layer 1 and a dielectric substrate 2 from top to bottom. In the embodiment of the present disclosure, the dielectric substrate 2 is made of a flame-retardant material with a relative dielectric constant of 4.4 and an electrical cutting loss of 0.02. The metal layer 1 is made of copper (Cu). The outer periphery of the metal layer 1 is a square structure with a size of 7.9mm*7.9mm, and the dielectric substrate is a square structure with a surface size of 8mm*8mm. In addition, in the embodiment of the present disclosure, the thickness of the dielectric substrate 2 is 1mm; the thickness of the metal layer 1 is in the range of 0.017mm-0.035mm. The frequency selective surface unit structure of the embodiment of the present disclosure is small in size, and the surface size of the overall unit structure is 8mm*8mm, which can meet the current trend of miniaturization of device structures.

[0032] In the embodiment of the present disclosure, a square ring patch 11 and a diamond ring combination patch 12 are provided on the metal layer 1; the center of the diamond ring combination patch 12 coincides with the center of the metal layer 1; the diamond ring combination patch 12 is composed of diamond ring patches 121 that are rotated 45° around the center of the structure; the square ring patch 11 is arranged around the diamond ring combination patch 12.

[0033] In the embodiment of the present disclosure, the square ring patch 11 and the diamond ring combination patch 12 are both axially symmetrical structures and centrally symmetrical structures; the diamond ring combination patch 12 includes eight diamond ring patches, which are formed based on the diamond ring patch 121 being rotated 45° around the center of the structure; the metal layer 1 is attached to the dielectric substrate 2; and the centers of the metal layer 1 and the dielectric substrate 2 coincide with each other.

[0034] Table 1 below shows the detailed geometric parameters of the metal layer 1 provided in the embodiment of the present disclosure.

[0035] Table 1. Detailed geometric parameters of the metal layer

[0036] parameter W1 W2 W3 value 6.4mm 0.32mm 0.75mm parameter L1 L2 L3 value 6.4mm 1.9mm 1.22mm parameter θ DX DY value 45° 7.9mm 7.9mm

[0037] Another disclosed embodiment of the present invention provides a high resonance ratio dual-stopband frequency selective surface multi-unit structure, the frequency selective surface structure comprising M×N periodically arranged frequency selective surface unit structures as described in any one of the above embodiments, wherein M and N are integers greater than or equal to 1. Figure 4 As shown, in the embodiment of the present disclosure, the frequency selective surface structure includes 10×10 unit structures; in specific applications, the frequency selective surface structure can include 20×20, 30×30, 40×40, or even more of the above unit structures according to actual needs.

[0038] In order to verify the performance of the frequency selective surface structure (FSS structure) of this embodiment, the embodiment of the present disclosure uses the commercial simulation software HFSS to perform multiple performance simulation analyses on the FSS structure.

[0039] Figure 5 : is a simulation diagram of the filtering performance of the high resonance ratio dual-stopband frequency selective surface provided by this embodiment in the TE polarization mode; Figure 5 The return loss (S11) and insertion loss (S21) in Figure 2 show that the two resonant frequencies of the FSS structure of this embodiment are 4.25 GHz and 25.32 GHz, with a resonant frequency ratio of 5.96. At the 4.25 GHz resonance point, the insertion loss is -47.74 dB, and the bandwidth at -10 dB is 3.94 GHz. At the 25.32 GHz resonance point, the insertion loss is -37.86 dB, and the bandwidth at -10 dB is 10.55 GHz. In other words, in the TE polarization mode, this FSS structure has a perfect band-stop effect for signals around frequencies of 4.25 GHz and 25.32 GHz.

[0040] Figure 6 : is a simulation diagram of the filtering performance of the high resonance ratio dual-stopband frequency selective surface provided by this embodiment in the TM polarization mode. Figure 6 The return loss (S11) and insertion loss (S21) in the figure show that the two resonant frequencies of the FSS structure of the disclosed embodiment are 4.05 GHz and 25.30 GHz, with a resonant frequency ratio of 6.25. At the 4.05 GHz resonance point, the insertion loss is -48.01 dB, and the bandwidth at -10 dB is 4.07 GHz; at the 25.30 GHz resonance point, the insertion loss is -37.78 dB, and the bandwidth at -10 dB is 10.64 GHz. In other words, in the TM polarization mode, the FSS structure has a perfect band-stop effect for signals with frequencies around 4.05 GHz and 25.30 GHz.

[0041] comprehensive Figure 5 and Figure 6From the performance simulation diagram, it can be seen that this structure has dual stopband performance in TE mode and TM mode, and the two resonant frequencies remain stable, that is, it has excellent polarization stability.

[0042] In addition, in order to study the angular stability of the FSS structure of this embodiment, it is irradiated with incident waves at incident angles of 0°, 15°, 30°, and 45° in TE mode and TM mode, and the frequency characteristics of the structure can be obtained. Figure 7 This is a simulation diagram of the angular stability performance of the high resonance ratio dual-stopband frequency selective surface structure provided by this embodiment under the TE polarization mode; Figure 8 This is a simulation diagram of the angular stability performance of the high resonance ratio dual-stopband frequency selective surface structure provided by this embodiment under the TM polarization mode.

[0043] from Figure 7 It can be seen that the FSS structure has strong angular stability and excellent band-stop characteristics at 4.25GHz and 25.32GHz. Under the irradiation of electromagnetic incident waves at different angles, the frequency deviation is within an acceptable range, and the resonant frequency ratio is always maintained at around 5.0, with excellent signal transmission capability and anti-interference capability.

[0044] from Figure 8 It can be seen that the FSS structure still has excellent angular stability and filtering characteristics at 4.05 GHz and 25.30 GHz. Under the irradiation of electromagnetic incident waves at different angles, the frequency deviation is within an acceptable range, and the resonant frequency ratio is always maintained at around 5.0, with excellent signal transmission capability and anti-interference ability.

[0045] comprehensive Figure 7 and Figure 8 It can be seen from the performance simulation diagram that this FSS structure always has a dual stopband effect when irradiated with incident waves at incident angles of 0°, 15°, 30° and 45° in TE mode and TM mode, and the resonance ratio remains stable, which confirms that this structure has excellent angular stability.

[0046] The high resonance ratio dual-stopband frequency selective surface structure described in the embodiment of the present disclosure has extremely strong band-stop characteristics near 4.25 GHz (C band) and 25.32 GHz (K band), and can be perfectly adapted to dual-band devices with a larger span.

[0047] The above is a further detailed description of the present invention in conjunction with specific preferred embodiments, and the specific implementation of the present invention should not be considered to be limited to these descriptions. For those skilled in the art of the present invention, without departing from the concept of the present invention, several simple deductions or substitutions can be made, which should be considered to fall within the scope of protection of the present invention.

Claims

1. A high resonance ratio dual-stopband frequency selective surface unit structure, characterized by: The invention comprises a metal layer (1) and a dielectric substrate (2) arranged in sequence from top to bottom; a square ring patch (11) and a rhombus ring combination patch (12) are arranged on the metal layer (1); the center of the rhombus ring combination patch (12) coincides with the center of the metal layer (1); the rhombus ring combination patch (12) is formed by combining rhombus ring patches (121) by rotating 45 degrees around the center of the structure; the square ring patch (11) is arranged around the rhombus ring combination patch (12); the resonant frequencies of the dual-stopband frequency selective surface unit structure are 4.25 GHz and 25.32 GHz, and the resonant frequency ratio is 5.

96.

2. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The square ring patch (11) and the diamond ring combination patch (12) are both axially symmetrical structures and centrally symmetrical structures.

3. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The diamond ring combination patch (12) includes eight diamond ring patches (121).

4. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The dielectric substrate (2) is a square structure.

5. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The metal layer (1) and the dielectric substrate (2) are centrally aligned.

6. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The dielectric substrate (2) is made of flame-resistant material; the metal layer (1) is made of metal; the metal includes copper, aluminum or gold.

7. The high resonance ratio dual-stopband frequency selective surface unit structure according to claim 1, characterized in that: The outer dimensions of the metal layer (1) are 7.9 mm*7.9 mm; the dimensions of the dielectric substrate (2) are 8 mm*8 mm.

8. A high resonance ratio dual-stopband frequency selective surface structure, characterized by: include M×N A periodically arranged frequency selective surface unit structure according to any one of claims 1 to 7, wherein M and N are integers greater than or equal to 1.

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