A wave-transmitting structure with low pass and wide resistance

Abstract

The present invention relates to the technical field of frequency selective wave-transmitting structures, and in particular to a wave-transmitting structure with low pass and wide resistance. In the wave-transmitting structure, the first FSS layer includes a plurality of first FSS layer basic units in a square shape, each of which is provided with a metal ring patch; the second FSS layer includes a plurality of second FSS layer basic units in a square shape, each of which is provided with two metal lines, one metal line extending from the first side of the second FSS layer basic unit to the second side opposite to the first side, and the other metal line extending from the third side of the second FSS layer basic unit to the fourth side opposite to the third side, and the two metal lines intersect at the middle part of the second FSS layer basic unit and form a labyrinth spiral structure. The present invention provides a structure that can still have excellent low-frequency selective wave-transmitting performance when electromagnetic waves are incident at a large angle.

Description

Technical Field

[0001] The invention relates to the technical field of frequency selective wave-transmitting structures, and in particular to a wave-transmitting structure with low pass and wide resistance. Background Art

[0002] Frequency selective wave-transmitting structures have a significant effect on suppressing electromagnetic scattering of radar antennas. On various targets equipped with radar sensors, a radome consisting of a special radar frequency selective wave-transmitting structure is used to improve the low detectability of the radar system.

[0003] The traditional frequency selective wave-transmitting structure can achieve frequency selective wave-transmitting performance, but the resonance point shifts when the electromagnetic wave is irradiated at a large incident angle, resulting in the problem that the frequency selective wave-transmitting structure is difficult to ensure stable bandpass performance when the electromagnetic wave is incident at a large angle, and this problem is more prominent when transmitting waves in lower frequency bands.

[0004] Therefore, in order to solve the above problems, it is necessary to provide a structure that can still have excellent low-frequency selective wave transmission performance when electromagnetic waves are incident at a large angle. Summary of the invention

[0005] The embodiment of the present invention provides a low-pass and wide-resistance wave-transmitting structure, which can provide a structure that still has excellent low-frequency selective wave-transmitting performance when electromagnetic waves are incident at a large angle.

[0006] The present invention provides a low-pass wide-resistance wave-transmitting structure, characterized in that the low-pass wide-resistance wave-transmitting structure comprises an absorbing layer, a first FSS layer, an absorbing layer, a foam layer, a skin layer, a second FSS layer, a skin layer, a foam layer, an absorbing layer, a first FSS layer, and an absorbing layer, which are sequentially arranged along a thickness direction;

[0007] The first FSS layer comprises a plurality of first FSS layer basic units in a square shape, each of which is provided with a metal ring patch;

[0008] The second FSS layer includes a plurality of square second FSS layer basic units, each of which is provided with two metal lines, one of which extends from a first side of the second FSS layer basic unit to a second side opposite to the first side, and the other of which extends from a third side of the second FSS layer basic unit to a fourth side opposite to the third side, and the two metal lines intersect in the middle of the second FSS layer basic unit and form a maze-shaped structure.

[0009] Preferably, the first FSS layer is composed of the first FSS layer basic units periodically arranged along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the first FSS layer basic unit.

[0010] Preferably, the second FSS layer is composed of the second FSS layer basic units periodically arranged along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the second FSS layer basic unit.

[0011] Preferably, the side length of the basic unit of the first FSS layer is 2-4 mm, the outer radius of the metal ring patch is 1.9-3.9 mm, and the patch width of the metal ring patch is 0.1-0.3 mm.

[0012] Preferably, the side length of the basic unit of the second FSS layer is 2-4 mm, the width of the metal line is 0.08-0.15 mm, and there is a gap between the two metal lines in the part forming the maze-shaped structure, and the size of the gap is 0.08-0.15 mm.

[0013] Preferably, the wave absorbing layer is made of a mixed material of hydroxy iron powder and resin.

[0014] Preferably, the foam layer is made of PMI foam.

[0015] Preferably, the skin layer is made of quartz fiber material.

[0016] Compared with the prior art, the present invention has at least the following beneficial effects:

[0017] In the present invention, a low-pass wide-resistance wave-transmitting structure comprises three FSS layers, wherein the middle layer of the three FSS layers is a second FSS layer composed of a plurality of second FSS layer basic units, and both sides of the three FSS layers are first FSS layers composed of a plurality of first FSS layer basic units, wherein the second FSS layer basic unit comprises two metal lines that extend in a zigzag manner and form a maze-shaped structure in the center, and the first FSS layer basic unit comprises a metal ring patch. By designing the first FSS layer basic unit as a square comprising a metal ring patch, designing the second FSS layer basic unit as a square comprising two metal lines that extend in a zigzag manner and form a maze-shaped structure in the center, and arranging the first FSS layer and the second FSS layer in the above order to form three FSS layers, the low-pass wide-resistance wave-transmitting structure provided by the present invention has stable low-frequency bandpass when electromagnetic waves are incident at large angles.

[0018] In the present invention, each FSS layer further includes an absorbing layer and a skin layer on both sides. The first FSS layer has absorbing layers on both sides, and the absorbing layers have a high relative dielectric constant, and have the performance of losing electromagnetic waves and improving the transmission of stopband cutoff electromagnetic waves in the high frequency band; the second FSS layer has skin layers on both sides, and the skin layers enable the low-pass and wide-resistance wave-transmitting structure to have excellent environmental adaptability.

[0019] In the present invention, a foam layer is also included between the absorbing layer and the skin layer. The foam layer has a low dielectric constant, close to that of air. The material is used in the structure mainly to space and support the first FSS layer and the second FSS layer, thereby achieving impedance matching in space. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 is a schematic diagram of a low-pass and wide-resistance wave-transmitting structure provided by an embodiment of the present invention;

[0022] Figure 2 is a schematic diagram of a first FSS layer basic unit provided by an embodiment of the present invention;

[0023] Figure 3 It is a schematic diagram of periodic arrangement of basic units of the first FSS layer provided by an embodiment of the present invention;

[0024] Figure 4 is a schematic diagram of a second FSS layer basic unit provided by an embodiment of the present invention;

[0025] Figure 5 It is a schematic diagram of periodic arrangement of basic units of the second FSS layer provided by an embodiment of the present invention;

[0026] Figure 6 is a diagram of wave transmittance at various incident angles when vertically polarized, provided by an embodiment of the present invention;

[0027] Figure 7 The embodiment of the present invention provides a diagram of the transmittance at various incident angles when horizontally polarized.

[0028] In the figure:

[0029] 1. Absorbing layer; 2. Foam layer; 3. Skin layer;

[0030] 4. First FSS layer; 41. First FSS layer basic unit;

[0031] 5. Second FSS layer; 51. Second FSS layer basic unit. DETAILED DESCRIPTION

[0032] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0033] In the description of the embodiments of the present invention, unless otherwise clearly specified and limited, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance; unless otherwise specified or explained, the term "multiple" refers to two or more; the terms "connected" and "fixed" should be understood in a broad sense, for example, "connected" can be a fixed connection, a detachable connection, an integral connection, or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0034] In the description of this specification, it should be understood that the directional words such as "upper" and "lower" described in the embodiments of the present invention are described at the angles shown in the drawings and should not be understood as limiting the embodiments of the present invention. In addition, in the context, it should also be understood that when it is mentioned that an element is connected to another element "upper" or "lower", it can not only be directly connected to another element "upper" or "lower", but also indirectly connected to another element "upper" or "lower" through an intermediate element.

[0035] like Figure 1 As shown, the present invention provides a low-pass wide-resistance wave-transmitting structure, characterized in that the low-pass wide-resistance wave-transmitting structure comprises an absorbing layer 1, a first FSS layer 4, an absorbing layer 1, a foam layer 2, a skin layer 3, a second FSS layer 5, a skin layer 3, a foam layer 2, an absorbing layer 1, a first FSS layer 4, and an absorbing layer 1 which are sequentially arranged in a thickness direction;

[0036] The first FSS layer 4 comprises a plurality of first FSS layer basic units 41 in a square shape, each of which is provided with a metal ring patch;

[0037] The second FSS layer 5 includes a plurality of square second FSS layer basic units 51, each of which is provided with two metal lines, one metal line extending from a first side of the second FSS layer basic unit 51 to a second side opposite to the first side, and the other metal line extending from a third side of the second FSS layer basic unit 51 to a fourth side opposite to the third side, and the two metal lines intersect in the middle part of the second FSS layer basic unit 51 and form a maze-shaped structure.

[0038] In the present invention, the low-pass wide-resistance wave-transmitting structure comprises three FSS layers, the middle layer of the three FSS layers is the second FSS layer 5 composed of a plurality of second FSS layer 5 basic units 51, the two sides of the three FSS layers are the first FSS layer 4 composed of a plurality of first FSS layer 4 basic units 41, the second FSS layer 5 basic unit 51 comprises two metal lines that extend in a zigzag manner and form a labyrinth-shaped structure in the center, and the first FSS layer 4 basic unit 41 comprises a metal ring patch. By designing the first FSS layer 4 basic unit 41 as a square comprising a metal ring patch, designing the second FSS layer 5 basic unit 51 as a square comprising two metal lines that extend in a zigzag manner and form a labyrinth-shaped structure in the center, and arranging the first FSS layer 4 and the second FSS layer 5 in the above order to form three FSS layers, the low-pass wide-resistance wave-transmitting structure provided by the present invention has stable low-frequency bandpass when electromagnetic waves are incident at large angles.

[0039] It should be noted that the metal ring patches on the multiple first FSS layer basic units 41 enable the first FSS layer 4 to have excellent equivalent capacitance performance; the two metal lines on the multiple second FSS layer basic units 51 that extend in a zigzag manner and form a maze-shaped structure in the center enable the second FSS layer 5 to have excellent equivalent inductance performance. The low-pass wide-resistance wave-transmitting structure is arranged in the order of the first FSS layer 4, the second FSS layer 5 and the first FSS layer, so that the low-pass wide-resistance wave-transmitting structure achieves excellent impedance matching. Therefore, when electromagnetic waves are incident at large angles, the passband is stable and the loss is small.

[0040] In addition, the first FSS layer basic unit 41 and the second FSS layer basic unit 51 are 1 / 4 symmetrical structures, are insensitive to the polarization of electromagnetic waves, and can achieve dual-polarization performance.

[0041] In the present invention, both sides of each FSS layer further include an absorbing layer 1 and a skin layer 3. Among them, the first FSS layer 4 is provided with the absorbing layer 1 on both sides, and the absorbing layer 1 has a high relative dielectric constant, and has the performance of losing electromagnetic waves and improving the transmission of stop-band cutoff electromagnetic waves in the high frequency band; the second FSS layer 5 is provided with the skin layer 3 on both sides, and the skin layer 3 enables the low-pass wide-resistance wave-transmitting structure to have excellent environmental adaptability.

[0042] In the present invention, a foam layer 2 is also included between the absorbing layer 1 and the skin layer 3. The foam layer 2 has a low dielectric constant, close to that of air. The material is used in the structure mainly to space and support the first FSS layer 4 and the second FSS layer 5, thereby achieving impedance matching in space.

[0043] According to some preferred embodiments, the first FSS layer 4 is composed of first FSS layer basic units 41 periodically arranged along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the first FSS layer basic unit 41 .

[0044] In the present invention, the basic units 41 of the first FSS layer are arranged periodically along the two adjacent sides thereof, so that the first FSS layer 4 forms a lossy layer array, thereby having the function of selecting the frequency of electromagnetic waves.

[0045] According to some preferred embodiments, the second FSS layer 5 is composed of second FSS layer basic units 51 periodically arranged along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the second FSS layer basic unit 51 .

[0046] In the present invention, the basic units 51 of the second FSS layer are arranged periodically along the two adjacent sides thereof, so that the second FSS layer 5 forms a lossy layer array, thereby having the function of selecting the frequency of electromagnetic waves.

[0047] According to some preferred embodiments, the side length of the first FSS layer basic unit 41 is 2-4 mm, the outer radius of the metal ring patch is 1.9-3.9 mm, and the patch width of the metal ring patch is 0.1-0.3 mm.

[0048] According to some preferred embodiments, the side length of the basic unit 51 of the second FSS layer is 2-4 mm, the width of the metal line is 0.08-0.15 mm, and there is a gap between the two metal lines in the part forming the maze-shaped structure, and the size of the gap is 0.08-0.15 mm.

[0049] In the present invention, by setting the side length of the first FSS layer basic unit 41, the side length of the second FSS layer basic unit 51, the outer radius of the metal ring patch, the patch width of the metal ring patch, the width of the metal line and the gap size between the metal lines forming a maze structure within the above-mentioned range, the first FSS layer 4 and the second FSS layer 5 have the performance of high-frequency cutoff and low-frequency resonance, and the electromagnetic wave signals outside the S band are reflected back, and the electromagnetic waves in the S band are selected to pass.

[0050] According to some preferred embodiments, the wave absorbing layer 1 is made of a mixed material of hydroxy iron powder and resin.

[0051] In the present invention, the absorbing layer 1 made of a mixed material of hydroxy iron powder and resin has high dielectric constant and loss tangent, has the performance of reducing the unit arrangement period and increasing high-frequency electromagnetic loss, and is applied to both sides of the first FSS layer 4.

[0052] According to some preferred embodiments, the foam layer 2 is made of PMI foam.

[0053] In the present invention, the foam layer 2 made of PMI foam has a low dielectric constant, has a supporting function, and realizes impedance matching in space.

[0054] According to some preferred embodiments, the skin layer 3 is made of quartz fiber material.

[0055] In the present invention, quartz fiber material is selected to make the skin layer 3 so that the low-pass and wide-resistance wave-transmitting structure provided by the present invention is suitable for high-intensity working environments.

[0056] Example:

[0057] Prepare a first FSS layer, wherein the side length of a basic unit of the first FSS layer is 3 mm, the outer radius of the metal ring patch is 2.9 mm, and the patch width is 0.2 mm;

[0058] A second FSS layer is prepared, wherein the side length of a basic unit of the second FSS layer is 3 mm, the width of the metal line is 0.1 mm, and the gap size between the metal lines of the maze-shaped structure is 0.2 mm;

[0059] Prepare an absorbing layer made of a mixture of hydroxy iron powder and resin, prepare a foam layer made of PMI foam, prepare a skin layer made of quartz fiber,

[0060] The absorbing layer, the first FSS layer, the absorbing layer, the foam layer, the skin layer, the second FSS layer, the skin layer, the foam layer, the absorbing layer, the first FSS layer, and the absorbing layer are arranged in sequence along the thickness direction, and the layers are bonded together using an adhesive to obtain a low-pass and wide-resistance wave-transmitting structure.

[0061] The obtained low-pass wide-resistance wave-transmitting structure is used to calculate the electromagnetic wave transmission performance. The specific calculation contents are as follows:

[0062] The electromagnetic waves of each band are injected into the low-pass wide-resistance wave-transmitting structure from different angles, and the power of the electromagnetic waves passing through the low-pass wide-resistance wave-transmitting structure is calculated to obtain the wave transmission results for horizontal polarization and vertical polarization, such as Figure 6 , Figure 7 shown.

[0063] Depend on Figure 6 and Figure 7 It can be seen that the calculation results of horizontal polarization and vertical polarization both lead to the following conclusion: only electromagnetic waves in the S band can pass through the low-pass wide-resistance wave-transmitting structure with small power loss.

[0064] In summary, the low-pass and wide-resistance wave-transmitting structure provided by the present invention has stable S-band passivity when electromagnetic waves are incident at large angles.

[0065] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A low-pass and wide-resistance wave-transmitting structure, characterized in that: The low-pass wide-resistance wave-transmitting structure comprises an absorbing layer (1), a first FSS layer (4), an absorbing layer (1), a foam layer (2), a skin layer (3), a second FSS layer (5), a skin layer (3), a foam layer (2), an absorbing layer (1), a first FSS layer (4), and an absorbing layer (1) which are arranged in sequence along the thickness direction; The first FSS layer (4) comprises a plurality of first FSS layer basic units (41) in a square shape, and each of the first FSS layer basic units (41) is provided with a metal annular patch; The second FSS layer (5) comprises a plurality of second FSS layer basic units (51) in a square shape, each of the second FSS layer basic units (51) being provided with two metal lines, one of the metal lines extending from a first side of the second FSS layer basic unit (51) to a second side opposite to the first side, and the other of the metal lines extending from a third side of the second FSS layer basic unit (51) to a fourth side opposite to the third side, the two metal lines intersecting at a middle portion of the second FSS layer basic unit (51) and forming a maze-shaped structure; The first FSS layer (4) is composed of the first FSS layer basic units (41) arranged periodically along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the first FSS layer basic unit (41); The second FSS layer (5) is composed of the second FSS layer basic units (51) arranged periodically along two adjacent sides thereof, and the minimum period of the arrangement is the side length of the second FSS layer basic unit (51); There is a gap between the two metal lines in the parts forming the maze-shaped structure; The wave absorbing layer (1) is made of a mixed material of hydroxy iron powder and resin, the foam layer (2) is made of PMI foam, and the skin layer (3) is made of quartz fiber material.

2. The low-pass wide-resistance wave-transmitting structure according to claim 1, characterized in that: The side length of the first FSS layer basic unit (41) is 2-4 mm, the outer radius of the metal ring patch is 1.9-3.9 mm, and the patch width of the metal ring patch is 0.1-0.3 mm.

3. The low-pass and wide-resistance wave-transmitting structure according to claim 1, characterized in that: The side length of the second FSS layer basic unit (51) is 2-4 mm, the width of the metal line is 0.08-0.15 mm, and the size of the gap is 0.08-0.15 mm.

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