Antenna structure based on interstitial waveguide

Abstract

This application provides an antenna structure based on a slot gap waveguide, comprising a first cover plate, a second cover plate, and an intermediate conductive plate spaced between the first and second cover plates; a first slot is provided on the surface of the first cover plate adjacent to the intermediate conductive plate; a second slot is provided in the intermediate conductive plate extending along its thickness direction; a plurality of first conductive pins are periodically distributed on the surface of the intermediate conductive plate adjacent to the first cover plate, the first cover plate, the intermediate conductive plate, and the plurality of first conductive pins constituting a first antenna element; a plurality of second conductive pins are periodically distributed on the surface of the intermediate conductive plate adjacent to the second cover plate, the second cover plate, the intermediate conductive plate, and the plurality of second conductive pins constituting a second antenna element; the first antenna element transmits horizontally polarized waves when fed with a signal alone, and the second antenna element transmits vertically polarized waves when fed with a signal alone; the first slot and the second slot are configured to achieve circular polarization characteristics when the first antenna element and the second antenna element are simultaneously fed with signals of equal amplitude and a phase difference of 90°.

Description

Technical Field

[0001] This application relates to the field of antenna technology, and in particular to an antenna structure based on a slot gap waveguide. Background Technology

[0002] With the rapid development of the communications field, low-frequency communication resources are becoming increasingly scarce, leading to a shift in research towards higher frequencies. Antennas, as components in wireless equipment used to transmit or receive electromagnetic waves, are also increasingly being studied in this area. Conventional microwave devices are simple in structure and have low loss, making them relatively mature in the low-frequency band. However, high-frequency microwave devices, such as waveguide antennas, are becoming increasingly small, making fabrication and integration difficult and resulting in degraded transmission performance. Recent advancements in electromagnetic metamaterials and metasurfaces have provided new directions for antenna development. Researchers have combined EBG structures with planar waveguides to develop new waveguide structures: gap waveguides. Further research has led to the development of ridge gap waveguides, slot gap waveguides, and others. Gap waveguides are all metallic and use air as the propagation medium, significantly reducing dielectric and radiation losses and greatly improving transmission performance. Furthermore, gap waveguides do not have strict electrical contact requirements, making them easy to mass-produce and integrate at low cost.

[0003] Currently, how to achieve circular polarization characteristics using a relatively simple structure is a problem that urgently needs to be solved. Summary of the Invention

[0004] This application aims to solve at least one of the technical problems existing in the prior art, and proposes an antenna structure based on slot gap waveguide.

[0005] To achieve the above objectives, this application provides an antenna structure based on a slot gap waveguide, comprising a first cover plate, a second cover plate, and an intermediate conductive plate spaced between the first cover plate and the second cover plate; a first slot is provided on the surface of the first cover plate adjacent to the intermediate conductive plate; a second slot is provided in the intermediate conductive plate extending along its thickness direction; a plurality of first conductive pins are periodically distributed on the surface of the intermediate conductive plate adjacent to the first cover plate, and the first cover plate, the intermediate conductive plate, and the plurality of first conductive pins constitute a first antenna element; a plurality of second conductive pins are periodically distributed on the surface of the intermediate conductive plate adjacent to the second cover plate, and the second cover plate, the intermediate conductive plate, and the plurality of second conductive pins constitute a second antenna element; the first antenna element transmits horizontally polarized waves when fed with a signal alone, and the second antenna element transmits vertically polarized waves when fed with a signal alone; the first slot and the second slot are configured to achieve circular polarization characteristics when the first antenna element and the second antenna element are simultaneously fed with signals of equal amplitude and a phase difference of 90°.

[0006] The antenna structure based on slot gap waveguide provided in this application has the advantages of slot gap waveguide, namely, low dielectric loss and radiation loss, high transmission performance, and the ability to achieve circular polarization characteristics using a doubly fed method. The first antenna element and the second antenna element share an intermediate conductive plate. Moreover, the first antenna element and the second antenna element are an integral antenna structure composed of two different slot gap waveguides (based on the first slot and the second slot). Thus, while achieving circular polarization characteristics, there are no strict electrical contact requirements, making it easy to carry out large-scale processing and integration, and the cost is low. Attached Figure Description

[0007] The above and / or additional aspects and advantages of this application will become apparent and readily understood from the description of the embodiments taken in conjunction with the following drawings, wherein:

[0008] Figure 1 A perspective view of the antenna structure provided in the embodiments of this application;

[0009] Figure 2 A cross-sectional view of the antenna structure provided in an embodiment of this application;

[0010] Figure 3 This is a bottom view of the first cover plate used in the embodiments of this application;

[0011] Figure 4 This is a bottom view of the second cover plate used in the embodiments of this application;

[0012] Figure 5 This is a bottom view of the intermediate conductive plate used in the embodiments of this application;

[0013] Figure 6 This is an assembly diagram of the first cover plate, the second cover plate, the intermediate conductive plate, and the stepped components used in the embodiments of this application;

[0014] Figure 7 A perspective view along the Y direction of the antenna structure provided in the embodiments of this application after assembly;

[0015] Figure 8 This is a perspective view of the stepped component used in the embodiments of this application;

[0016] Figure 9 This is a dimensional diagram of the first conductive screw used in the embodiments of this application;

[0017] Figure 10 A graph showing the S-parameters of the antenna structure provided in this application embodiment without the aforementioned antenna end structure;

[0018] Figure 11Gain diagram of the antenna structure provided in the embodiments of this application without the above-described antenna end structure;

[0019] Figure 12 A 3dB axial ratio curve of the circular polarization of the antenna structure provided in the embodiments of this application without the above-mentioned antenna end structure;

[0020] Figure 13 The far-field radiation pattern of the antenna structure provided in the embodiments of this application without the above-described antenna end structure;

[0021] Figure 14 A graph showing the S-parameters of the antenna structure provided in the embodiments of this application when the above-described antenna end structure is provided;

[0022] Figure 15 Gain diagram of the antenna structure provided in the embodiments of this application within the operating bandwidth when the above-described antenna end structure is provided;

[0023] Figure 16 The circular polarization bandwidth diagram of the overall antenna operation when the antenna structure provided in the embodiments of this application is provided with the above-mentioned antenna end structure;

[0024] Figure 17 The antenna structure provided in this application embodiment, when equipped with the above-described antenna end structure, shows the antenna radiation pattern at different frequencies when the entire antenna is fed separately from the top or from the bottom. Detailed Implementation

[0025] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this application, and should not be construed as limiting this application.

[0026] In the description of this application, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientation or positional relationships based on the orientation or positional relationships shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first" and "second" may explicitly or implicitly include one or more features. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0027] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection, an electrical connection, or a connection that allows communication between them; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0028] The following disclosure provides many different embodiments or examples for implementing different structures of this application. To simplify the disclosure, specific examples of components and arrangements are described below. Of course, these are merely examples and are not intended to limit the scope of this application. Furthermore, reference numerals and / or letters may be repeated in different examples; such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed. In addition, various specific examples of processes and materials are provided in this application, but those skilled in the art will recognize the application of other processes and / or the use of other materials.

[0029] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with an embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0030] Please refer to the following: Figure 1 and Figure 2 This application provides an antenna structure based on a slot-gap waveguide, which can be applied to high-frequency band base stations, satellite communications, and other application scenarios. This antenna structure possesses the advantages of slot-gap waveguides, namely, low dielectric loss and radiation loss, high transmission performance, and simplifies the structure by utilizing a doubly-fed method to achieve circular polarization characteristics. Furthermore, it does not have strict electrical contact requirements, is easy to mass-produce and integrate, and has low cost.

[0031] Specifically, please refer to the following: Figures 1 to 7 The antenna structure 100 includes a first cover plate 1, a second cover plate 2, and an intermediate conductive plate 3 spaced between the first cover plate 1 and the second cover plate 2. For example, such as Figure 1 and Figure 2 As shown, the first cover plate 1, the intermediate conductive plate 3, and the second cover plate 2 are arranged alternately from top to bottom. A first groove 11 is formed on the surface of the first cover plate 1 adjacent to the intermediate conductive plate 3 (i.e., the lower surface). The depth (dimension along the Y direction) of the first groove 11 is less than the thickness (dimension along the Y direction) of the first cover plate 1; that is, the first groove 11 is a blind groove that does not penetrate the first cover plate 1. A second groove 31 is formed in the intermediate conductive plate 3, penetrating along its thickness direction (dimension along the Y direction). Figure 4 As shown, the second cover plate 2 is an ungrooved metal plate. Furthermore, the surface of the intermediate conductive plate 3 adjacent to the first cover plate 1 (i.e., the upper surface) is provided with a plurality of periodically distributed first conductive pins 4. The first cover plate 1, the intermediate conductive plate 3, and the plurality of first conductive pins 4 constitute a first antenna unit. The surface of the intermediate conductive plate 3 adjacent to the second cover plate 2 (i.e., the lower surface) is provided with a plurality of periodically distributed second conductive pins 5. The second cover plate 2, the intermediate conductive plate 3, and the plurality of second conductive pins 5 constitute a second antenna unit.

[0032] As can be seen from the above structure, the first antenna unit and the second antenna unit share the intermediate conductive plate 3. Moreover, the first antenna unit and the second antenna unit are an integral antenna structure composed of two different slot gap waveguides (based on the first slot 11 and the second slot 31), which simplifies the structure while achieving circular polarization characteristics.

[0033] Specifically, the first antenna element, composed of the first cover plate 1, the intermediate conductive plate 3, and multiple first conductive pins 4, transmits horizontally polarized waves when fed with a signal alone. The second antenna element, composed of the second cover plate 2, the intermediate conductive plate 3, and multiple second conductive pins 5, transmits vertically polarized waves when fed with a signal alone. The first slot 11 and the second slot 31 are configured to achieve circular polarization characteristics when the first and second antenna elements are simultaneously fed with signals of equal amplitude and a phase difference of 90°. That is, the embodiment of this application uses a dual-feed method to achieve circular polarization characteristics. This method of achieving circular polarization characteristics is simpler than the single-feed power divider method in related technologies. Moreover, the embodiment of this application is an integral structure composed of the first antenna element and the second antenna element, and each of the first and second antenna elements can also achieve independent feeding operation.

[0034] Furthermore, in some embodiments, by designing relevant dimensions such as the dimensions of the first cover plate 1, the intermediate conductive plate 3, the first slot 11, and the second slot 31, the slot gap waveguide based on the first slot 11 and the second slot 31 can achieve the transmission of horizontally polarized waves and vertically polarized waves, respectively, while simultaneously enabling electromagnetic waves to propagate along the signal transmission direction of the slot gap waveguide within a certain frequency range. This frequency range is, for example, greater than or equal to 10 GHz and less than or equal to 20 GHz. Taking the orthographic projection shape of both the first slot 11 and the second slot 31 on a plane parallel to the intermediate conductive plate 3 as an example, where both are isosceles trapezoids, the dimensions of the first slot 11 and the second slot 31 are, for example, the length of the top side and the length of the bottom side of the isosceles trapezoid. Taking the orthographic projection shape of both the first cover plate 1 and the intermediate conductive plate 3 on a plane parallel to the intermediate conductive plate 3 as an example, where both the dimensions of the first cover plate 1 and the intermediate conductive plate 3 are, for example, the length and width of a rectangle. The dimensions of the second cover plate 2 are, for example, the same as the dimensions of the first cover plate 1.

[0035] like Figure 1 and Figure 7 As shown, a plurality of first conductive pins 4 and a plurality of second conductive pins 5, arranged in a periodic pattern, are used to block electromagnetic waves propagating in the first groove 11 and the second groove 31 from moving to both sides (i.e., along). Figure 1 and Figure 7 The electromagnetic wave propagates along the X2 direction of the first slot 11 and the second slot 31, thereby allowing the electromagnetic wave to propagate along the signal transmission direction (e.g., along the X2 direction). Figure 1 and Figure 7 The signal propagation direction is defined as the direction from the first slot 11 to the second slot 31 (in the X1 direction). In other words, multiple first conductive pins 4 and multiple second conductive pins 5 can form a waveguide structure for transmitting electromagnetic waves with the first slot 11 and the second slot 31. The arrangement of the first conductive pins 4 and the second conductive pins 5 is the basis for realizing the transmission of vertically polarized waves and horizontally polarized waves. For ease of description, the above signal transmission direction is defined as the direction from the beginning of the signal input to the end of the signal output in the first slot 11 or the second slot 31 (i.e., Figures 1 to 7 (From left to right) This direction is parallel to Figure 1 and Figure 7 The X1 direction in the text. It is easy to understand that the actual propagation direction of the electromagnetic wave in the first tank 11 and the second tank 31 may be the same as or different from the signal transmission direction described above.

[0036] In some embodiments, the cross-sectional shape of the first conductive pin 4 and the second conductive pin 5 includes, for example, a cuboid, a cube, or a cylinder. Each first conductive pin 4 and each second conductive pin 5 can be coaxially arranged in a one-to-one correspondence or slightly offset. The first cover plate 1, the second cover plate 2, and the intermediate conductive plate 3 are all metal plates.

[0037] In some embodiments, the second groove 31 and the first groove 11 are coaxial in their orthographic projections onto a plane parallel to the intermediate conductive plate 3. That is, as shown... Figure 6 and Figure 7 As shown, the orthographic projection of the axis of the first slot 11 onto the plane parallel to the intermediate conductive plate 3 is O1, and the orthographic projection of the axis of the second slot 31 onto the plane parallel to the intermediate conductive plate 3 is O2, and the two coincide. In this way, two different slot gap waveguides based on the second slot 31 and the first slot 11 are coaxially arranged.

[0038] In some embodiments, such as Figure 3 As shown, the opening size of the first slot 11 is along its signal transmission direction (i.e., Figure 3 The opening increases from left to right along the X1 direction; this opening is the slot of the first groove 11 on the lower surface of the first cover plate 1. The opening size refers to the dimension of the first groove 11 as its orthographic projection onto a plane parallel to the intermediate conductive plate 3, along a direction perpendicular to the signal transmission direction, i.e., along the X2 direction. The end of the first groove 11 along the signal transmission direction is located on the side (right side) of the first cover plate 1 corresponding to this end; that is, the first groove 11 forms an end opening on the right side of the first cover plate 1. Figure 5 As shown, the opening size of the second slot 31 is along its signal transmission direction (i.e., Figure 3The opening size increases from left to right along the X1 direction. This opening size refers to the dimension of the second groove 31 as a projection of its orthographic projection onto a plane parallel to the intermediate conductive plate 3, along a direction perpendicular to the signal transmission direction, i.e., along the X2 direction. The end of the second groove 31 along the signal transmission direction is located on the side (right side) of the intermediate conductive plate 3 corresponding to this end; that is, the second groove 31 forms an end opening on the right side of the intermediate conductive plate 3. In summary, both the first groove 11 and the second groove 31 are "trumpet" shaped, thus forming a waveguide with a cross-section (perpendicular to the signal transmission direction) that gradually widens along the signal transmission direction and is rectangular or square.

[0039] In some embodiments, such as Figure 7 As shown, the first groove 11 and the second groove 31 are each arranged with a first array consisting of multiple first conductive pins 4 and a second array consisting of multiple second conductive pins 5 on both sides along the first direction; the first direction is perpendicular to the signal transmission direction of the first groove 11 and the second groove 31, that is, the first direction is parallel to the signal transmission direction of the second groove 31. Figure 7 In the X2 direction. Furthermore, the first array is in a first direction that is perpendicular to each other (parallel to...) Figure 7 (in the X2 direction) and the second direction (parallel to) Figure 7 The first array is arranged in the X1 direction, and the first conductive pins 4 arranged in the first direction are called "rows", and each row includes at least three first conductive pins 4 arranged in the first direction; the second array is arranged in the first direction and the second direction, and the first conductive pins 4 arranged in the first direction of the second array are called "rows", and each row includes at least three second conductive pins 5 arranged in the first direction. In a specific embodiment, in Figure 7 In the first slot 11 and the second slot 31, the aforementioned first array and second array are distributed on the outer sides of the two oblique sides along the first direction. The number of conductive pins in each row increases as they approach the left side. However, the row at the end of the first and second arrays includes no fewer than three second conductive pins 5. Simulation experiments (e.g., CST simulation) show that having more than three conductive pins in each row can effectively block electromagnetic waves propagating in the slot gap waveguide from both sides (i.e., along the first direction). Figure 7 (Propagation in the X2 direction). It should be noted that when the two oblique sides of the first groove 11 are located outside the two oblique sides of the second groove 31, as... Figure 7 As shown, a few scattered second conductive pins 5' are arranged on the inner sides of the two oblique sides of the first slot 11 and on the outer side of the second slot 31, but this does not affect the antenna function and effect. It is easy to understand that the first conductive pins 4 and the second conductive pins 5 are both set on the middle conductive plate 3, but their arrangement is located on both sides of the first slot 11 and the second slot 31 along the first direction.

[0040] In some embodiments, in order to transmit horizontally polarized waves, a third groove 12 is further provided on the surface (i.e., the lower surface) of the first cover plate 1 adjacent to the intermediate conductive plate 3. The third groove 12 is located on the side of the signal input end (i.e., the beginning end of the signal input) of the first groove 11. Figure 3 The third groove 12 is located on the left side of the first groove 11 and is connected to the first groove 11; further, in some embodiments, the third groove 12 is coaxially arranged with the first groove 11. And, as... Figure 7 As shown, the third tank 12 is along the aforementioned second direction (parallel to) Figure 7 On the side of the third groove 12 away from the first groove 11 (i.e., the left side of the third groove 12) in the X1 direction, a third array composed of multiple first conductive pins 4 and a fourth array composed of multiple second conductive pins 5 are arranged. The third array is arranged in the first and second directions, and the first conductive pins 4 arranged in the second direction are called "columns", and each column includes at least three first conductive pins 4 arranged in the second direction. The fourth array is arranged in the first and second directions, and the second conductive pins 5 arranged in the second direction are called "columns", and each column includes at least three second conductive pins 5 arranged in the second direction. In this way, electromagnetic waves propagating in the third groove 12 can be effectively blocked. Figure 7 The propagation occurs on the left side of the third tank 12. Furthermore, the side of the third tank 12 furthest from the first tank 11 (i.e....) Figure 3 The left side of the third groove 12 has at least three rows of orthographic projections of first conductive pins 4' and at least three rows of orthographic projections of second conductive pins. Figure 7 (The middle section is not shown due to obstruction). This effectively blocks electromagnetic waves propagating in the third tank 12 from reaching the left end (i.e., along...). Figure 7 It propagates in the X1 direction (from right to left).

[0041] like Figure 3 and Figure 4 As shown, a first signal feed section 13 extending through its thickness is provided on the first cover plate 1. The first signal feed section 13 is, for example, a metal through-hole provided on the first cover plate 1. A second signal feed section 21 extending through its thickness is provided on the second cover plate 2. On a plane parallel to the intermediate conductive plate 3, the orthographic projections of the first signal feed section 13 and the second signal feed section 21 fall into the orthographic projection of the third groove 12, and are coaxial with each other. This enables coaxial signal feeding.

[0042] In some embodiments, such as Figure 1 and Figure 2As shown, the antenna structure 100 also includes an end conductive plate 6, a plurality of third conductive pins 7, and a plurality of fourth conductive pins 8. The end conductive plate 6 is disposed at the end of the intermediate conductive plate 3. This end is the side (i.e., the right side) of the intermediate conductive plate 3 corresponding to the signal transmission end of the second slot 31. The plurality of third conductive pins 7 are disposed on the surface (i.e., the upper surface) of the end conductive plate 6 adjacent to the first cover plate 1, and are arranged in a fifth array. This fifth array is arranged in a first direction and a second direction. The third conductive pins 7 arranged in the second direction of the fifth array are called "columns", and each column includes the third conductive pins 7 arranged in the second direction (parallel to the first cover plate 1). Figure 7 At least three third conductive pins 7 are arranged in the X1 direction (in the first direction); a plurality of fourth conductive pins 8 are arranged in a sixth array, which is arranged in the first and second directions. The fourth conductive pins 8 arranged in the second direction of the sixth array are called "columns", and each column includes at least three fourth conductive pins 8 arranged in the second direction. When the first antenna element is fed with a signal alone, or when the second antenna element is fed with a signal alone, the antenna end structure composed of the end conductive plate 6, a plurality of third conductive pins 7 and a plurality of fourth conductive pins 8 can enable beam scanning of electromagnetic waves within the operating frequency band, thereby increasing the functionality of the antenna structure 100 and making it suitable for more application scenarios. In order to obtain better impedance characteristics, each column of the fifth array includes at least three fourth conductive pins 8 arranged in the second direction (parallel to the second direction). Figure 7 At least three third conductive pins 7 are arranged in the X1 direction, and each column of the sixth array includes at least three fourth conductive pins 8 arranged in the second direction.

[0043] Furthermore, in some embodiments, each column of the fifth array includes columns in the second direction (parallel to) Figure 7 At least four third conductive pins 7 are arranged in the X1 direction (in the middle), and each column of the sixth array includes at least four fourth conductive pins 8 arranged in the second direction, which facilitates antenna miniaturization. The multiple third conductive pins 7 and multiple fourth conductive pins 8 can be coaxially arranged in a one-to-one correspondence or slightly offset. The end conductive plate 6 and the middle conductive plate 3 are connected in a detachable manner, for example, so that the end conductive plate 6 can be installed or removed according to different needs. Since the antenna structure 100 in this embodiment does not have strict electrical contact requirements, screws can be used to fix the end conductive plate 6 to the end of the middle conductive plate 3.

[0044] Furthermore, in some embodiments, by optimizing the size and structure of the plurality of third conductive pins 7 and the plurality of fourth conductive pins 8, beams pointing in different directions at different frequencies within the operating bandwidth can be achieved. For example, to achieve electromagnetic wave propagation at different frequencies, the height of the third conductive pins 7 arranged in the second direction in each column of the fifth array increases along the signal transmission direction of the second slot 31; the height of the fourth conductive pins 8 arranged in the second direction in each column of the sixth array increases along the signal transmission direction of the second slot 31. For example, as... Figure 1 and Figure 2 As shown, in the fifth array, each column includes four third conductive pins 7 arranged in the second direction, with the height increasing from left to right. In the sixth array, each column includes four fourth conductive pins 8 arranged in the second direction, with the height increasing from left to right. The cross-sectional shapes of the third conductive pins 7 and the fourth conductive pins 8 include, for example, cuboids, cubes, or cylinders.

[0045] In some embodiments, such as Figure 2 , Figure 6 and Figure 8 As shown, the antenna structure 100 also includes a stepped component 9 for impedance matching. This stepped component 9 is disposed on the surface (i.e., the lower surface) of the intermediate conductive plate 3 adjacent to the second cover plate 2. The stepped component 9 includes multiple stepped portions arranged sequentially along the signal transmission direction of the second groove 31, with their heights decreasing sequentially. For example, as... Figure 8 As shown, the stepped component 9 includes a first step portion 91, a second step portion 92, and a third step portion 93. The first step portion 91, the second step portion 92, and the third step portion 93 are arranged sequentially along the signal transmission direction of the second groove 31 (i.e., from left to right along a direction parallel to X1), and their heights decrease sequentially. It should be noted that the height of the step portion refers to the height protruding from the surface (i.e., the lower surface) of the intermediate conductive plate 3 adjacent to the second cover plate 2.

[0046] The relevant parameters of the antenna structure in this application embodiment can be as follows: In a specific embodiment, such as Figures 3 to 5 As shown, both the first cover plate 1 and the intermediate conductive plate 3 are rectangular or square plates. The side length of the first cover plate 1 parallel to the signal transmission direction of the first groove 11 (i.e., parallel to the X1 direction) is a first length Ly. The side length of the intermediate conductive plate 3 parallel to the signal transmission direction of the second groove 31 (i.e., parallel to the X1 direction) is a second length Ly1. The first length Ly is greater than or equal to the second length Ly1. The second cover plate 2 has the same shape and size (but different thickness) as the first cover plate 1, and is also a rectangular or square plate. The side length of the second cover plate 2 parallel to the signal transmission direction of the first groove 11 (i.e., parallel to the X1 direction) is equal to the first length Ly. Furthermore, the left sides of the first cover plate 1, the second cover plate 2, and the intermediate conductive plate 3 are aligned.

[0047] In some embodiments, the second length satisfies the following relationship:

[0048] Ly1 = n × P;

[0049] Where Ly1 is the second length; n is an integer greater than 0 and less than 20; P = 1a + D, where P is the periodic dimension of the periodic distribution of the first conductive pin 4, specifically, as shown in... Figure 9 As shown, la is the dimension of the first conductive pin 4 along the signal transmission direction of the second slot 31 (i.e., parallel to the X1 direction); D is the spacing between each pair of adjacent first conductive pins 4 along the signal transmission direction of the second slot 31 (i.e., parallel to the X1 direction). To meet the miniaturization requirements of the antenna structure, the value of n is kept as small as possible. The dimensions of the periodically distributed second conductive pins 5 can be the same as those of the first conductive pins 4, that is, each second conductive pin 5 is coaxially arranged in a one-to-one correspondence with each first conductive pin 4; or, the dimensions of the periodically distributed second conductive pins 5 can be slightly different from those of the first conductive pins 4, that is, each second conductive pin 5 is slightly offset from each first conductive pin 4 in a one-to-one correspondence.

[0050] In embodiments including the end conductive plate 6, such as Figure 7 As shown, the length of the end conductive plate 6 along the signal transmission direction parallel to the first groove 11 (i.e., parallel to the X1 direction) is the fifth length Ly2. During assembly, an assembly space of the fifth length Ly2 needs to be reserved on the right side of the middle conductive plate 3 for the end conductive plate 6.

[0051] In some embodiments, such as Figures 3 to 5 As shown, the side length of the first cover plate 1 perpendicular to the signal transmission direction of the first groove 11 (i.e., parallel to the X2 direction) is the third length (i.e., W); the side length of the middle conductive plate 3 perpendicular to the signal transmission direction of the second groove 31 is the fourth length (i.e., W).

[0052] The third length is equal to the fourth length, and the following relationship is satisfied:

[0053] W = m × P;

[0054] Where W represents the third and fourth lengths, in practical applications, W = m × P ± w, where w is the reserved assembly distance; m is a value greater than 0 and less than 20; P = 1a + D, where P is the periodic dimension of the first conductive pins 4 distributed periodically. To achieve miniaturization of the antenna structure, the value of m is kept as small as possible. Furthermore, the shape and size of the second cover plate 2 can be consistent with the shape and size of the first cover plate 1. Additionally, the length of the end conductive plate 6 along the signal transmission direction perpendicular to the first slot 11 (i.e., parallel to the X2 direction) can be equal to the third and fourth lengths.

[0055] In some embodiments, such as Figure 3 and Figure 5 As shown, the maximum value of the opening size of the first slot 11 perpendicular to the signal transmission direction of the first slot 11 (i.e., parallel to the X2 direction) is the first maximum value W2; the maximum value of the opening size of the second slot 31 perpendicular to the signal transmission direction of the second slot 31 (i.e., parallel to the X2 direction) is the second maximum value W4; and the first maximum value W2 is equal to the second maximum value W4.

[0056] Furthermore, in some embodiments, the first maximum value W2 and the second maximum value W4 satisfy the following relationship:

[0057] (W-W4) / 2>3×P;

[0058] Among them, the first maximum value W2 is equal to the second maximum value W4.

[0059] In some embodiments, such as Figure 7 As shown, the end conductive plate 6 is a rectangular or square plate; the side length of the end conductive plate 6 parallel to the signal transmission direction of the second groove 31 (i.e., parallel to the X1 direction) is the fifth length Ly2; the fifth length Ly2 satisfies the following relationship:

[0060] Ly2=nn×P±L

[0061] Where nn is an integer greater than 0 and less than 5; L is a preset value to allow for assembly distance. P is the periodic dimension of the first conductive pins 4 that are periodically distributed. To meet the miniaturization requirements of the antenna structure, the value of nn is kept as small as possible.

[0062] In some embodiments, the interval between each first conductive pin 4 and the first cover plate 1 is a first interval (i.e., G), and the interval between each second conductive pin 5 and the second cover plate 2 is a second interval (i.e., G). The first interval is equal to the second interval and satisfies the following relationship:

[0063] G < 1 / 4λ

[0064] Where G represents the first and second intervals, and λ represents the wavelength of the electromagnetic wave.

[0065] In some embodiments, such as Figure 2 As shown, the heights of the third conductive pin 7 and the fourth conductive pin 8 along the Y direction are less than or equal to the heights of the first conductive pin 4 and the second conductive pin 5 along the Y direction.

[0066] In practical applications, parameters affecting the antenna's operating bandwidth include P, la, G, and the heights of the first conductive pin 4 and the second conductive pin 5 along the Y direction. Adjusting at least one of these parameters allows the antenna structure to operate in other frequency bands. Furthermore, to make the antenna operate in other high-frequency bands, the following conditions must be met: G < 1 / 4λ, and P > la. Simulations of these parameters reveal the following relationship between the stopband and these parameters: When the heights of the first conductive pin 4 and the second conductive pin 5 along the Y direction decrease, the overall frequency of the stopband increases, and the stopband width increases. When G (i.e., the first and second intervals) decreases, the stopband bandwidth increases. When La (the dimension of the first conductive pin 4 along the signal transmission direction of the second slot 31 (i.e., parallel to the X1 direction)) is reached, the upper limit of the stopband's value range increases, and the lower limit of the stopband's value range decreases slightly. However, exceeding this range and further increasing the value of La actually decreases the stopband bandwidth. To achieve antenna miniaturization and performance optimization, frequencies above 30 GHz can be selected. In this case, the heights of P, Ia, G, the first conductive pin 4, and the second conductive pin 5 along the Y direction are all less than or equal to 1 mm.

[0067] In one specific embodiment, the first length Ly is 78mm; the second length Ly1 is 85mm; W is 79mm; W1 is the minimum opening size of the first groove 11 perpendicular to the signal transmission direction of the first groove 11 (i.e., parallel to the X2 direction), which is 7mm; the first maximum value W2 is 45mm; W3 is the minimum opening size of the second groove 31 perpendicular to the signal transmission direction of the second groove 31 (i.e., parallel to the X2 direction), which is 8mm; the second maximum value W4 is 45mm; the thickness of the first cover plate 1 is 7.5mm; the depth of the first groove 11 is 6mm; the thickness of the intermediate conductive plate 3 is 3mm; the thickness of the second cover plate 2 is 2mm; the height of the first conductive pin 4 and the second conductive pin 5 along the Y direction is 6mm; la is 2mm; P is 4.5mm; the fifth length Ly2 is 17mm; and the thickness of the end conductive plate 6 is 0.7mm. Figure 2 Counting from right to left, the height of the first third conductive pin 7 and the first fourth conductive pin 8 along the Y direction is 6mm; the height of the second third conductive pin 7 and the second fourth conductive pin 8 along the Y direction is 3mm; the height of the third third conductive pin 7 and the third fourth conductive pin 8 along the Y direction is 2.5mm; the height of the fourth third conductive pin 7 and the fourth fourth conductive pin 8 along the Y direction is 0.5mm; the height of the first step 91 is 1mm, and the length along the X1 direction is 5mm; the height of the second step 92 is 0.7mm, and the length along the X1 direction is 8mm; the height of the third step 93 is 0.3mm, and the length along the X1 direction is 6mm; G is 1mm.

[0068] By simulating the antenna structure using the above parameters in the embodiments of this application, the following simulation results can be obtained: Figure 10 As shown, without the aforementioned antenna end structure (consisting of an end conductive plate 6, multiple third conductive pins 7, and multiple fourth conductive pins 8), curves S11 / S22 represent the reflection coefficients of port 1 / 2, and curves S12 / S21 represent the isolation of port 1 / 2, respectively. The vertical axis represents the values ​​of the S-parameters; the horizontal axis represents the frequency. In antenna structure 100, the bandwidth range of the first antenna element is 16.5GHz-19.3GHz; the bandwidth range of the second antenna element is 17GHz-19GHz. Figure 11 As shown, within the frequency band where both ports 1 and 2 are operational, the gain of antenna structure 100 within its operating bandwidth is approximately 11 dBi. Figure 12 As shown, the 3dB axial ratio curve of the antenna structure 100 with circular polarization has a circular polarization bandwidth of 17.3GHz-19GHz. Figure 13 This shows the far-field method diagram of the antenna structure in the E-plane / H-plane within the operating bandwidth, from... Figure 13 It can also be seen from the data that this antenna structure can achieve circular polarization characteristics.

[0069] With the aforementioned antenna end structure (consisting of an end conductive plate 6, multiple third conductive pins 7, and multiple fourth conductive pins 8), the antenna structure 100 can not only achieve circular polarization characteristics but also beam scanning. Simulation results are as follows: Figures 14 to 17 As shown: In this antenna structure 100, Figure 14 A graph showing the S-parameters of the antenna structure provided in this application embodiment when the above-described antenna end structure is provided. Figure 15 This is the gain diagram of the entire antenna within its operating bandwidth. Figure 16 The circular polarization bandwidth diagram for overall antenna operation. Figure 17 The diagram shows the antenna radiation patterns at different frequencies when the antenna is fed from above or below, represented by curves of different colors. From this, it can be seen that: the bandwidth of the first antenna element is 16.5GHz-18.9GHz; the bandwidth of the second antenna element is 17GHz-19.3GHz; and the gain range of antenna structure 100 is 5dBi-8dBi. Figure 16 It can be seen that the antenna structure using the above parameters in the embodiments of this application can also achieve circular polarization characteristics. From Figure 17 It can be seen that the beam points in different directions at different frequencies, and the beam scanning range is from 50° to 130°, thus enabling beam scanning.

[0070] It is understood that the above embodiments are merely exemplary implementations used to illustrate the principles of this application, and this application is not limited thereto. For those skilled in the art, various modifications and improvements can be made without departing from the spirit and substance of this application, and these modifications and improvements are also considered to be within the scope of protection of this application.

Claims

1. An antenna structure based on a slot gap waveguide, wherein, It includes a first cover plate, a second cover plate, and an intermediate conductive plate spaced between the first cover plate and the second cover plate; The first cover plate has a first groove on the surface adjacent to the intermediate conductive plate; the intermediate conductive plate has a second groove extending through its thickness direction. The intermediate conductive plate has a plurality of first conductive pins arranged in a periodic manner on the surface adjacent to the first cover plate. The first cover plate, the intermediate conductive plate, and the plurality of first conductive pins constitute a first antenna unit. The intermediate conductive plate has a plurality of second conductive pins arranged in a periodic manner on the surface adjacent to the second cover plate. The second cover plate, the intermediate conductive plate, and the plurality of second conductive pins constitute a second antenna unit. The first antenna element transmits a horizontally polarized wave when fed with a signal alone, and the second antenna element transmits a vertically polarized wave when fed with a signal alone; the first slot and the second slot are configured to achieve circular polarization characteristics when the first antenna element and the second antenna element are simultaneously fed with signals of equal amplitude and phase difference of 90°.

2. The antenna structure according to claim 1, wherein, The second groove and the first groove are coaxial in their orthographic projections onto a plane parallel to the intermediate conductive plate.

3. The antenna structure according to claim 1, wherein, The opening size of the first slot increases along its signal transmission direction; the opening size of the second slot increases along its signal transmission direction.

4. The antenna structure according to claim 1, wherein, The first groove and the second groove are each arranged with a first array consisting of a plurality of first conductive pins and a second array consisting of a plurality of second conductive pins on both sides along the first direction; the first array is arranged in a first direction and a second direction that are perpendicular to each other, and each row includes at least three first conductive pins arranged in the first direction. The second array is arranged in the first direction and the second direction, and each row includes at least three second conductive pins arranged in the first direction; The first direction is perpendicular to the signal transmission direction of the first and second slots.

5. The antenna structure according to claim 4, wherein, A third groove is provided on the surface of the first cover plate adjacent to the intermediate conductive plate. The third groove is located on the signal input end side of the first groove and is connected to the first groove. The third groove has a third array consisting of a plurality of first conductive pins and a fourth array consisting of a plurality of second conductive pins arranged on the side away from the first groove along the second direction; the third array is arranged in the first direction and the second direction, and each column includes at least three first conductive pins arranged in the second direction. The fourth array is arranged in the first direction and the second direction, and each column includes at least three second conductive pins arranged in the second direction; The first cover plate is provided with a first signal feed section extending through its thickness, and the second cover plate is provided with a second signal feed section extending through its thickness. On a plane parallel to the intermediate conductive plate, the orthographic projections of the first signal feed section and the second signal feed section fall into the orthographic projection of the third groove, and are coaxial with each other.

6. The antenna structure according to any one of claims 1-5, wherein, The antenna structure further includes an end conductive plate, multiple third conductive pins, and multiple fourth conductive pins, wherein the end conductive plate is disposed at the end of the intermediate conductive plate; A plurality of third conductive pins are disposed on the surface of the end conductive plate adjacent to the first cover plate and arranged in a fifth array. The fifth array is arranged in a first direction and a second direction that are perpendicular to each other, and each column includes at least three third conductive pins arranged in the second direction. A plurality of fourth conductive pins are arranged in a sixth array. The sixth array is arranged in the first direction and the second direction, and each column includes at least three fourth conductive pins arranged in the second direction. The first direction is perpendicular to the signal transmission direction of the first groove and the second groove.

7. The antenna structure according to claim 6, wherein, The height of the third conductive pins arranged in the second direction in each column increases along the signal transmission direction of the second groove; the height of the fourth conductive pins arranged in the second direction in each column increases along the signal transmission direction of the second groove.

8. The antenna structure according to any one of claims 1-5, wherein, Both the first cover plate and the intermediate conductive plate are rectangular or square plates; the side length of the first cover plate parallel to the signal transmission direction of the first groove is a first length; the side length of the intermediate conductive plate parallel to the signal transmission direction of the second groove is a second length. The first length is greater than or equal to the second length.

9. The antenna structure according to claim 8, wherein, The second length satisfies the following relationship: Ly1 = n × P; Where Ly1 is the second length; n is an integer greater than 0 and less than 20; P = la + D, where la is the dimension of the first conductive pin along the signal transmission direction of the second groove; D is the interval dimension of each two adjacent first conductive pins along the signal transmission direction of the second groove.

10. The antenna structure according to claim 8, wherein, The side length of the first cover plate perpendicular to the signal transmission direction of the first groove is the third length; the side length of the intermediate conductive plate perpendicular to the signal transmission direction of the second groove is the fourth length. The third length is equal to the fourth length, and satisfies the following relationship: W = m × P; Wherein, W represents the third length and the fourth length; m is a value greater than 0 and less than 20; P = la + D, where la is the dimension of the first conductive pin along the signal transmission direction of the second groove; and D is the interval dimension between each two adjacent first conductive pins along the signal transmission direction of the second groove.

11. The antenna structure according to claim 10, wherein, The maximum value of the opening size of the first slot perpendicular to the signal transmission direction of the first slot is a first maximum value; the maximum value of the opening size of the second slot perpendicular to the signal transmission direction of the second slot is a second maximum value. The first maximum value is equal to the second maximum value.

12. The antenna structure according to claim 11, wherein, The first maximum value and the second maximum value satisfy the following relationship: (W-W4) / 2>3×P; Wherein, W4 represents the first maximum value and the second maximum value.

13. The antenna structure according to claim 6, wherein, The end conductive plate is a rectangular or square plate; the side length of the end conductive plate parallel to the signal transmission direction of the second groove is the fifth length; the fifth length satisfies the following relationship: Ly2=nn×P±L Where Ly2 is the fifth length; nn is an integer greater than 0 and less than 5; and L is a preset value.

14. The antenna structure according to any one of claims 1-5, wherein, The interval between each of the first conductive pins and the first cover plate is the first interval, and the interval between each of the second conductive pins and the second cover plate is the second interval. The first interval is equal to the second interval, and satisfies the following relationship: G < 1 / 4λ Wherein, G represents the first interval and the second interval; λ represents the wavelength of the electromagnetic wave.

15. The antenna structure according to claim 6, wherein, It also includes a stepped component for impedance matching, the stepped component being disposed on the surface of the intermediate conductive plate adjacent to the second cover plate, the stepped component comprising a plurality of stepped portions arranged sequentially along the signal transmission direction of the second groove, with the height decreasing sequentially.

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