A low insertion loss energy selective surface

Abstract

The present invention relates to a low-insertion-loss energy selective surface, comprising: a plurality of strip units and a plurality of auxiliary units; the strip units and the auxiliary units are both strip-shaped structures, and the auxiliary units and the strip units are alternately arranged in sequence; the strip units include: a plurality of strip modules; the auxiliary units include: a plurality of auxiliary modules; the strip modules include: a first dielectric substrate and a first electromagnetic induction component arranged on one side of the first dielectric substrate; the auxiliary modules include: a second dielectric substrate and a second electromagnetic induction component arranged on one side of the second dielectric substrate; the first dielectric substrate and the second dielectric substrate are identical; the first electromagnetic induction component and the second electromagnetic induction component are arranged in parallel, and the first electromagnetic induction component and the second electromagnetic induction component are arranged on the same side of the low-insertion-loss energy selective surface.

Description

Technical Field

[0001] The present invention relates to the technical field of strong electromagnetic pulse protection, in particular to a low insertion loss energy selective surface. Background Art

[0002] Antennas, as essential components of wireless communication systems, play a crucial role in modern communications. Practical communication systems often require filtering of received signals at the antenna front end to achieve a certain level of anti-interference capability. Frequency-selective surfaces (FSs) and energy-selective surfaces (ESSs) are two technical approaches used for antenna front-end filtering. FSSs are metasurfaces composed of two-dimensional or three-dimensional periodic structures with spatial filtering properties, exhibiting different selectivity for electromagnetic wave frequencies. ESSs, on the other hand, are metasurfaces with both frequency and energy filtering properties, formed by adding nonlinear devices to traditional FSSs. ESSs, based on the principle of field-induced impedance variation, can switch between high and low impedance under varying field intensities, resulting in two states: a high-impedance state for wave transmission and a low-impedance state for shielding. The wave-transmitting state allows signals within the frequency band to pass through normally, while the shielding state shields signals within the frequency band from the ESS. The signal transmission efficiency in both the wave-transmitting and shielding states is typically defined as insertion loss (IL) and shielding effectiveness (SE).

[0003] In the microwave field, energy-selective surfaces can be used to make antenna covers, achieving the effects of antenna stealth and protection. For example, Chinese patent CN114692541A discloses an efficient field-circuit collaborative simulation method based on spatial mapping technology. In its scheme, an energy-selective surface and a periodic structure are designed, in which a single strip unit and a diode are used to achieve the corresponding effect. For another example, Chinese patent CN101754668A discloses an electromagnetic energy-selective surface, which discloses a strip unit in a single linear polarization to achieve the corresponding effect.

[0004] For a single linearly polarized strip-shaped energy-selective surface, its impedance is primarily determined by metal inductance and diode capacitance. The greater the metal inductance and the smaller the diode capacitance, the greater the impedance of the energy-selective surface in its wave-transmitting state, and the lower its wave-transmitting insertion loss. Furthermore, within the low-frequency band (UHF-L band), the effect of diode capacitance on the energy-selective surface's impedance is far greater than that of metal inductance. Therefore, the size of the diode capacitance directly determines the energy-selective surface's insertion loss. As the diode capacitance increases, the energy-selective surface's insertion loss significantly increases. In its protective state, the energy-selective surface's impedance is primarily determined by its metal inductance. The smaller the metal inductance, the smaller the energy-selective surface's impedance, and the greater its shielding effectiveness. Summary of the Invention

[0005] The purpose of the present invention is to provide a low insertion loss energy selective surface to solve the dependence of the energy selective surface insertion loss on diode parameters and achieve low insertion loss when the diode performance is poor.

[0006] To achieve the above-mentioned object of the invention, the present invention provides a low insertion loss energy selective surface, comprising: a plurality of strip-shaped units and a plurality of auxiliary units;

[0007] The strip units and the auxiliary units are both strip-shaped structures, and the auxiliary units and the strip units are alternately arranged in sequence;

[0008] The strip unit includes: a plurality of strip modules;

[0009] The auxiliary unit includes: a plurality of auxiliary modules;

[0010] The strip module includes: a first dielectric substrate and a first electromagnetic induction component arranged on one side of the first dielectric substrate;

[0011] The auxiliary module includes: a second dielectric substrate and a second electromagnetic induction component arranged on one side of the second dielectric substrate;

[0012] The first dielectric substrate and the second dielectric substrate are identical;

[0013] The first electromagnetic induction component and the second electromagnetic induction component are arranged in parallel, and the first electromagnetic induction component and the second electromagnetic induction component are arranged on the same side of the low insertion loss energy selection surface.

[0014] According to one aspect of the present invention, the first electromagnetic induction component includes: a first metal strip and a PIN diode;

[0015] There are two first metal strips, which are aligned with each other and spaced apart;

[0016] The PIN diode is located between the two first metal strips, and two ends of the PIN diode are respectively connected to the ends of the first metal strips.

[0017] According to one aspect of the present invention, the first dielectric substrate is a square plate;

[0018] The first metal strip is in a rectangular strip shape, and its longitudinal symmetry axis is aligned with a symmetry axis of the first dielectric substrate;

[0019] One end of the first metal strip away from the PIN diode is arranged flush with a side edge of the first dielectric substrate.

[0020] According to one aspect of the present invention, the length l1 of the first metal strip satisfies:

[0021] l1=(p-d1) / 2

[0022] Wherein, p represents the side length of the first dielectric substrate, and d1 represents the spacing distance between two first metal strips.

[0023] According to one aspect of the present invention, the side length p of the first dielectric substrate is: 4 mm ≤ p ≤ 6 mm;

[0024] The spacing distance d1 between the two first metal strips is: 0.6 mm ≤ d1 ≤ 1.2 mm;

[0025] The width w1 of the first metal strip is: 0.8 mm ≤ w1 ≤ 2.5 mm.

[0026] According to one aspect of the present invention, the second electromagnetic induction component includes: a second metal strip;

[0027] There are two second metal strips, which are aligned with each other and spaced apart.

[0028] According to one aspect of the present invention, the second dielectric substrate is a square plate;

[0029] The second metal strip is a long symmetrical structure, and its symmetry axis in the length direction is aligned with a symmetry axis of the second dielectric substrate.

[0030] According to one aspect of the present invention, the second metal strip comprises: a first rectangular portion and a second rectangular portion perpendicular to each other;

[0031] The second rectangular portion is connected to one end of the first rectangular portion;

[0032] One end of the first rectangular portion away from the second rectangular portion is aligned with a side edge of the second dielectric substrate.

[0033] According to one aspect of the present invention, the first rectangular portion, the second rectangular portion, and the second dielectric substrate satisfy the following conditions:

[0034] 2*l2+2*w3<p

[0035] Wherein, p represents the side length of the second dielectric substrate, l2 represents the length of the first rectangular portion, and w3 represents the width of the second rectangular portion;

[0036] The length l2 of the first rectangular portion is: 1.5mm≤l2≤2.5mm, and the width w2 thereof is 0.1≤w2≤2mm;

[0037] The length l3 of the second rectangular portion is: 0.5mm≤l3≤2.5mm, and the width w3 thereof is 0.1≤w3≤0.8mm.

[0038] According to one aspect of the present invention, the operating band of the low insertion loss energy selective surface is the UHF band and the L band.

[0039] According to one solution of the present invention, the present invention adopts a combination of different units to effectively reduce the influence of diode capacitance on the impedance of the energy selective surface, thereby achieving low insertion loss of the energy selective surface in a wave-transmitting state.

[0040] According to one solution of the present invention, the low insertion loss energy selective surface of the present invention has the dual characteristics of frequency selection and energy selection: in the frequency domain, it is equivalent to a spatial filter, which can selectively pass through the incident wave within the set frequency band (UHF-L band); in the energy domain, when a low-energy signal is incident, it can form the above-mentioned frequency domain filtering characteristics, and when the energy of the incident wave exceeds a certain threshold, it can adaptively switch states, shielding the incident wave within the working frequency band, and preventing high-power signals from entering the signal channel through the antenna.

[0041] According to one solution of the present invention, the present invention works in the UHF band and the L band, and can adaptively change its own working state according to the energy of the incident electromagnetic wave. Without affecting the normal working signal, it can adaptively shield the high-power incident wave to protect the safety of the subsequent circuit.

[0042] According to one solution of the present invention, the present invention has a simple structure and is easy to process, and can be widely used in shielding radio frequency front-end antennas of communication systems, which is of great significance to promoting the development of antenna covers in my country. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 is a diagram schematically showing the structure of a low insertion loss energy selective surface according to an embodiment of the present invention;

[0044] Figure 2 is a structural diagram schematically showing a bar module according to one embodiment of the present invention;

[0045] Figure 3 is a dimensioned diagram schematically showing a bar module according to one embodiment of the present invention;

[0046] Figure 4 is a structural diagram schematically showing an auxiliary module according to one embodiment of the present invention;

[0047] Figure 5 is a dimensioned diagram schematically showing an auxiliary module according to one embodiment of the present invention;

[0048] Figure 6is a diagram schematically showing an equivalent circuit model of a low insertion loss energy selective surface in a wave-transmitting state according to an embodiment of the present invention;

[0049] Figure 7 is a diagram schematically showing an equivalent circuit model of a low insertion loss energy selective surface in a protection state according to an embodiment of the present invention;

[0050] Figure 8 is a diagram schematically showing an equivalent circuit model of a conventional energy selective surface in a wave-transmitting state;

[0051] Figure 9 is a diagram schematically showing an equivalent circuit model of a conventional energy selective surface in a protection state;

[0052] Figure 10 It is a diagram schematically showing the transmission coefficient of a low insertion loss energy selective surface in a wave-transmitting and protective state according to an embodiment of the present invention and a comparison with the transmission coefficient of a traditional energy selective surface in the wave-transmitting and protective state. DETAILED DESCRIPTION

[0053] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be derived from these drawings without inventive effort.

[0054] When describing the embodiments of the present invention, the orientation or positional relationship expressed by the terms "longitudinal", "transverse", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" are based on the orientation or positional relationship shown in the relevant drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operate in a specific orientation. Therefore, the above terms should not be understood as limiting the present invention.

[0055] The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments. The embodiments cannot be described one by one here, but the embodiments of the present invention are not limited to the following embodiments.

[0056] Combine Figure 1 、 Figure 2 、 Figure 3 、 Figure 4 and Figure 5As shown, according to one embodiment of the present invention, a low insertion loss energy selection surface of the present invention includes: a plurality of strip units 1 and a plurality of auxiliary units 2. In this embodiment, the strip units 1 and the auxiliary units 2 are both strip structures, and the auxiliary units 2 and the strip units 1 are arranged alternately in sequence. In this embodiment, along the width direction of the strip units 1 and the auxiliary units 2, the auxiliary units 2 and the strip units 1 are connected to each other in an alternating arrangement. For example, the first column uses the auxiliary unit 2, and the second column is connected to the auxiliary unit 2. The subsequent units are arranged in this arrangement.

[0057] In this embodiment, the strip unit 1 includes a plurality of strip modules 11. The strip unit 1 forms a strip structure by sequentially connecting the plurality of strip modules 11. In this embodiment, the strip modules 11 include a first dielectric substrate 111 and a first electromagnetic induction component 112 disposed on one side of the first dielectric substrate 111.

[0058] In this embodiment, the auxiliary unit 2 includes a plurality of auxiliary modules 21. The auxiliary unit 2 is formed into a strip-like structure by sequentially connecting the plurality of auxiliary modules 21. In this embodiment, the auxiliary module 21 includes a second dielectric substrate 211 and a second electromagnetic induction component 212 disposed on one side of the second dielectric substrate 211.

[0059] In this embodiment, the first dielectric substrate 111 and the second dielectric substrate 211 are identical; the first electromagnetic induction component 112 and the second electromagnetic induction component 212 are arranged in parallel, and the first electromagnetic induction component 112 and the second electromagnetic induction component 212 are arranged on the same side of the low insertion loss energy selection surface.

[0060] Combine Figure 1 、 Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the first electromagnetic induction component 112 includes: a first metal strip 1121 and a PIN diode 1122. In this embodiment, two first metal strips 1121 are provided, aligned with each other and spaced apart. The PIN diode 1122 is located between the two first metal strips 1121, with its two ends connected to the ends of the first metal strips 1121. In this embodiment, the PIN diode 1122 can also be replaced by a semiconductor diode with switching characteristics.

[0061] Combine Figure 1 、 Figure 2 and Figure 3As shown, according to one embodiment of the present invention, the first dielectric substrate 111 is a square plate; the first metal strip 1121 is a rectangular strip, with its longitudinal axis of symmetry aligned with one of the axes of symmetry of the first dielectric substrate 111. In this embodiment, the end of the first metal strip 1121 away from the PIN diode 1122 is flush with a side edge of the first dielectric substrate 111.

[0062] Combine Figure 1 、 Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the length l1 of the first metal strip 1121 satisfies:

[0063] l1=(p-d1) / 2

[0064] Wherein, p represents the side length of the first dielectric substrate 111 , and d1 represents the spacing distance between the two first metal strips 1121 .

[0065] Combine Figure 1 、 Figure 2 and Figure 3 As shown, according to one embodiment of the present invention, the side length p of the first dielectric substrate 111 is: 4mm≤p≤6mm; the spacing distance d1 between the two first metal strips 1121 is: 0.6mm≤d1≤1.2mm. In this embodiment, the width w1 of the first metal strip 1121 is: 0.8mm≤w1≤2.5mm.

[0066] Combine Figure 1 、 Figure 4 and Figure 5 As shown, according to one embodiment of the present invention, the second electromagnetic induction component 212 includes: a second metal strip 2121. In this embodiment, two second metal strips 2121 are provided, which are aligned with each other and spaced apart.

[0067] Combine Figure 1 、 Figure 4 and Figure 5 As shown, according to one embodiment of the present invention, the second dielectric substrate 211 is a square plate; the second metal strip 2121 is a long symmetrical structure, and its longitudinal axis of symmetry is aligned with one of the symmetry axes of the second dielectric substrate 211.

[0068] Combine Figure 1 、 Figure 4 and Figure 5As shown, according to one embodiment of the present invention, the second metal strip 2121 includes a first rectangular portion 2121a and a second rectangular portion 2121b that are perpendicular to each other. In this embodiment, the second rectangular portion 2121b is connected to one end of the first rectangular portion 2121a. When the two second metal strips 2121 are aligned and spaced apart, the two second rectangular portions 2121b are positioned opposite each other. In this embodiment, the end of the first rectangular portion 2121a that is away from the second rectangular portion 2121b is aligned with a side edge of the second dielectric substrate 211.

[0069] Combine Figure 1 、 Figure 4 and Figure 5 As shown, according to one embodiment of the present invention, the first rectangular portion 2121a, the second rectangular portion 2121b and the second dielectric substrate 211 satisfy the following conditions:

[0070] 2*l2+2*w3<p

[0071] Wherein, p represents the side length of the second dielectric substrate 211, l2 represents the length of the first rectangular portion 2121a, and w3 represents the width of the second rectangular portion 2121b.

[0072] In this embodiment, the length l2 of the first rectangular portion 2121a is: 1.5mm≤l2≤2.5mm, and its width w2 is 0.1≤w2≤2mm; the length l3 of the second rectangular portion 2121b is: 0.5mm≤l3≤2.5mm, and its width w3 is 0.1≤w3≤0.8mm.

[0073] like Figure 1 As shown, according to one embodiment of the present invention, the operating bands of the low insertion loss energy selective surface are the UHF band and the L band.

[0074] Since insertion loss and shielding effectiveness are conflicting indicators, the lower the designed insertion loss, the lower the shielding effectiveness. Therefore, in actual applications, it is necessary to comprehensively consider insertion loss and shielding effectiveness and select the appropriate size based on the above setting range.

[0075] According to the present invention, the low-insertion-loss energy selective surface has two operating states: a wave-transmitting state and a protective state. When the incident electromagnetic wave energy is low, the diode is zero-biased, and the energy selective surface is in the wave-transmitting state, transmitting electromagnetic waves within the low-frequency band (UHF-L band) with an insertion loss of less than 1.5dB. When the incident electromagnetic wave energy exceeds the designed threshold, the diode is forward-biased, and the energy selective surface is in the protective state. The wave-transmitting band is closed, and the in-band signal is shielded from the energy selective surface, thereby protecting the subsequent circuitry.

[0076] In order to further illustrate the working principle of the present invention, it is described in conjunction with its equivalent circuit model.

[0077] As mentioned above, Figure 6 and Figure 7 As shown, the low insertion loss energy selective surface of the present invention utilizes the switching characteristics of the diode to achieve the energy selective characteristics of the energy selective surface. When the incident electromagnetic wave energy is small, the diode is in a zero bias state, and the energy selective surface behaves as a wave-transmitting state. At this time, its equivalent circuit model is as follows: Figure 6 As shown, its impedance can be calculated as:

[0078] Z Low-power =(jωL1+1 / jωC d ) / / (jωL2+1 / jωC s )

[0079] According to the insertion loss calculation formula of the energy selective surface, the insertion loss of the present invention can be expressed as:

[0080]

[0081] Where Z0 is the air impedance.

[0082] In contrast, the equivalent circuit model of the traditional energy selective surface with single linear polarization mentioned in the background technology is as follows: Figure 8 and Figure 9 As shown, the impedance when it is in the wave-transmitting state can be calculated as:

[0083] Z Low-power(1) =(jωL1+1 / jωC d ) / / (jωL1+1 / jωC d )

[0084] The insertion loss formula is similar to the aforementioned insertion loss formula and will not be repeated here.

[0085] It can be seen that the capacitor C of the auxiliary module 21 used in this solution s Much smaller than the diode capacitance C d , and then Z Low-power >Z Low-power(1) According to the insertion loss calculation formula, it can be seen that the low insertion loss energy selective surface of this scheme has lower insertion loss than the traditional energy selective surface.

[0086] Furthermore, when the energy of the incident electromagnetic wave exceeds a certain limit, the induced voltage across the PIN diode exceeds the conduction threshold of the diode, the PIN diode is turned on, and the energy selection surface switches to the protection state. At this time, the diode is equivalent to a resistor with a small resistance R dAt this time, the circuit is short-circuited by inductor L1 in the low-frequency band (UHF-L band), and the incident wave cannot be transmitted through. Therefore, when a high-energy incident wave is sensed, the entire structure adaptively switches to the protection state, which can form a good shielding effect and protect the subsequent circuit from damage. Figure 7 shown.

[0087] To further illustrate this solution, an example is given.

[0088] Example

[0089] In this embodiment, both the first dielectric substrate 111 and the second dielectric substrate 211 are FPCN boards, with a thickness h1 of 0.13 mm. The PIN diode 1122 in the first electromagnetic induction component 112 is BAP51-02. Other dimensional parameters of the first dielectric substrate 111, the second dielectric substrate 211, and the first and second metal strips 1121 and 2121 are summarized in Table 1 (unit: mm):

[0090] Table 1

[0091]

[0092] For comparison, a corresponding conventional energy selective surface is constructed based on the above parameters, that is, the conventional energy selective surface is constructed using the same strip modules 11 as those in this embodiment.

[0093] Based on the above parameters, a comparative simulation is conducted on the low insertion loss energy selective surface of the present invention and the traditional energy selective surface. Figure 10 As shown in the figure, in the wave-transmitting state, the low-insertion-loss energy selective surface of the present invention has an insertion loss of less than 1.5dB below the L-band, which is a significant improvement over the 3.5dB insertion loss of conventional energy selective surfaces. It should be noted that the shielding effectiveness of the low-insertion-loss energy selective surface of the present invention is also reduced in the protective state.

[0094] The low insertion loss design proposed in the present invention is obtained by comparison under the condition that the parameters of the strip units and diodes are the same.

[0095] The above contents are merely examples of specific solutions of the present invention. For devices and structures not described in detail, it should be understood that they can be implemented by adopting general devices and methods available in the art.

[0096] The above description is merely one embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A low insertion loss energy selective surface, characterized in that: include: A plurality of bar-shaped units (1) and a plurality of auxiliary units (2); The strip-shaped units (1) and the auxiliary units (2) are both strip-shaped structures, and the auxiliary units (2) and the strip-shaped units (1) are arranged alternately in sequence; The strip unit (1) comprises: a plurality of strip modules (11); The auxiliary unit (2) comprises: a plurality of auxiliary modules (21); The strip module (11) comprises: a first dielectric substrate (111) and a first electromagnetic induction component (112) arranged on one side of the first dielectric substrate (111); The auxiliary module (21) comprises: a second dielectric substrate (211) and a second electromagnetic induction component (212) arranged on one side of the second dielectric substrate (211); The first dielectric substrate (111) and the second dielectric substrate (211) are identical; The first electromagnetic induction component (112) and the second electromagnetic induction component (212) are arranged in parallel, and the first electromagnetic induction component (112) and the second electromagnetic induction component (212) are arranged on the same side of the low insertion loss energy selection surface; The first electromagnetic induction component (112) comprises: a first metal strip (1121) and a PIN diode (1122); There are two first metal strips (1121), which are aligned with each other and spaced apart. The PIN diode (1122) is located between the two first metal strips (1121), and its two ends are respectively connected to the ends of the first metal strips (1121); The first dielectric substrate (111) is a square plate; The first metal strip (1121) is in the shape of a rectangular strip, and its longitudinal axis of symmetry is aligned with a symmetry axis of the first dielectric substrate (111); One end of the first metal strip (1121) away from the PIN diode (1122) is arranged flush with a side edge of the first dielectric substrate (111); The second electromagnetic induction component (212) comprises: a second metal strip (2121); There are two second metal strips (2121), which are aligned with each other and spaced apart. The second dielectric substrate (211) is a square plate; The second metal strip (2121) is a long symmetrical structure, and its symmetry axis in the length direction is aligned with a symmetry axis of the second dielectric substrate (211); The second metal strip (2121) comprises a first rectangular portion (2121a) and a second rectangular portion (2121b) perpendicular to each other; The second rectangular portion (2121b) is connected to one end of the first rectangular portion (2121a); One end of the first rectangular portion (2121a) away from the second rectangular portion (2121b) is aligned with a side edge of the second dielectric substrate (211).

2. The low insertion loss energy selective surface according to claim 1, characterized in that: The length l1 of the first metal strip (1121) satisfies: l1=(p-d1) / 2 Wherein, p represents the side length of the first dielectric substrate (111), and d1 represents the spacing distance between the two first metal strips (1121).

3. The low insertion loss energy selective surface according to claim 2, characterized in that: The side length p of the first dielectric substrate (111) is: 4mm≤p≤6mm; The spacing distance d1 between the two first metal strips (1121) is: 0.6 mm ≤ d1 ≤ 1.2 mm; The width w1 of the first metal strip (1121) is: 0.8mm≤w1≤2.5mm.

4. The low insertion loss energy selective surface according to claim 3, characterized in that: The first rectangular portion (2121a), the second rectangular portion (2121b) and the second dielectric substrate (211) satisfy the following conditions: 2*l2+2*w3<p Wherein, p represents the side length of the second dielectric substrate (211), l2 represents the length of the first rectangular portion (2121a), and w3 represents the width of the second rectangular portion (2121b); The length l2 of the first rectangular portion (2121a) is: 1.5mm≤l2≤2.5mm, and the width w2 thereof is 0.1≤w2≤2mm; The length l3 of the second rectangular portion (2121b) is: 0.5mm≤l3≤2.5mm, and the width w3 thereof is 0.1≤w3≤0.8mm.

5. The low insertion loss energy selective surface according to claim 4, characterized in that: The operating bands of the low insertion loss energy selective surface are the UHF band and the L band.

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