Miniaturized decoupling array antenna

Abstract

The invention belongs to the technical field of antennas, and particularly discloses a miniaturized decoupling array antenna which comprises a mounting plate, a plurality of antenna elements and a cross-shaped metal frame, the antenna elements are distributed on the surface of the mounting plate in an array mode, each antenna element comprises a substrate, a grounding plate is arranged on the surface, facing the mounting plate, of each substrate, and the cross-shaped metal frame is arranged on the grounding plate. Radiation patches and slow-wave patches are arranged on the surface, deviating from the mounting plate, of the substrate, and the slow-wave patches are distributed around the radiation patches to form a slow-wave structure; and a plurality of cross metal frames are arranged on the surface of the mounting plate, and are integrally arranged among the plurality of antenna elements in a cross manner to form a cross decoupling band. According to the array antenna, the miniaturization design can be realized under the condition that the electromagnetic characteristics of the antenna are not changed, the coupling effect between the antenna elements can be weakened, and the antenna gain directional diagram can be improved.

Description

Technical Field

[0001] The present application belongs to the field of antenna technology, and more specifically, relates to a miniaturized decoupled array antenna. Background Art

[0002] With the rapid development of wireless radio frequency communication systems, the multifunctional integration and common-aperture miniaturized design of communication antennas has gradually become a trend.

[0003] In the related art, in order to centrally arrange antennas with different functions and frequency bands or array antennas with the same frequency band on the same mounting surface, a high dielectric constant substrate or slots in the substrate are often used to miniaturize the antenna. However, this design is performed at the expense of antenna gain and other performance. When multiple antennas with different frequency bands or array antennas with the same frequency band are centrally arranged, the decoupling effect of the array antenna is often poor due to the influence of the carrier environment, resulting in poor final performance of the array antenna, which urgently needs to be improved. Summary of the invention

[0004] In response to the defects or improvement needs of the prior art, the present application provides a miniaturized decoupled array antenna, which can achieve miniaturization design without changing the electromagnetic characteristics of the antenna, and can weaken the coupling effect of the antenna and improve the antenna gain pattern.

[0005] The present application provides a miniaturized decoupling array antenna, which specifically includes a mounting plate, an antenna element and a cross metal frame, wherein: The antenna elements are arranged in a plurality of arrays on the surface of the mounting plate. The antenna elements include a substrate. A ground plate is arranged on the surface of the substrate facing the mounting plate. A radiation patch and a slow-wave patch are arranged on the surface of the substrate facing away from the mounting plate. The slow-wave patches are arranged around the radiation patch to form a slow-wave structure. A plurality of cross metal frames are arranged on the surface of the mounting plate, and are arranged in a cross shape between a plurality of antenna elements to form a cross decoupling belt.

[0006] Through the above technical scheme conceived by the present application, compared with the prior art, a stronger distributed capacitance C will be formed between the slow-wave patch designed in the present design scheme and the ground plane, which is equivalent to increasing the equivalent dielectric constant of the dielectric substrate, thereby reducing the phase velocity of the radiated electromagnetic wave and further shortening the wavelength, thereby realizing the miniaturization design of the array antenna without changing the electromagnetic characteristics of the antenna.

[0007] On this basis, the cross metal frame arranged crosswise on the surface of the mounting plate can effectively reduce the strong mutual coupling between antenna elements and suppress the surface waves caused by the close arrangement of antenna elements, thereby reducing reverse radiation and improving antenna gain, thus ensuring antenna performance.

[0008] As a further preference, the slow-wave patches are arranged in a linear array along the side lengths of the radiation patches to form a linear patch array.

[0009] As a further preferred embodiment, two patch arrays located on two adjacent sides of the radiation patch maintain a gap at the edge corners of the radiation patch.

[0010] As a further preference, the slow-wave patches are arranged in a staggered lattice on the sides of the radiation patches to form a lattice-shaped patch array.

[0011] As a further preferred embodiment, two patch arrays located on two adjacent sides of the radiation patch form a gap channel at the edge corners of the radiation patch, and the gap channel extends along the diagonal line of the radiation patch.

[0012] As further preferred, the slow-wave patch and / or the radiation patch is a square patch.

[0013] As further preferred, the cross metal frame includes a cross bottom plate and a support column arranged at the center of the top surface of the cross bottom plate.

[0014] As a further preference, the cross metal frames are distributed in a staggered matrix between two adjacent antenna elements.

[0015] As a further preference, the cross metal frames are cross-distributed in a single row and a single column at the center of the cross area surrounded by the antenna elements.

[0016] As a further preference, the antenna further comprises an antenna cover, which is fixed to the mounting plate and covers the antenna element and the cross metal frame.

[0017] In general, the above technical solutions conceived by this application have the following technical advantages compared with the prior art: 1. This design forms a slow-wave structure by designing the structural distribution of the slow-wave patch, and a strong distributed capacitance is formed between the slow-wave patch and the ground plane, which can reduce the propagation speed of the electromagnetic wave of the array antenna, so that the structural size of the array antenna can be greatly reduced without changing the electromagnetic characteristics of the antenna; and the loaded cross metal frame arranged crosswise can effectively reduce the strong mutual coupling of the antenna elements on the mounting plate, suppress the surface waves caused by the close arrangement of the antenna elements, and achieve the effect of reducing reverse radiation and improving the antenna gain, so that the antenna pattern of the antenna is not easy to be deformed when the installation size is limited.

[0018] 2. Through structural design and distribution design of the cross metal frame, the cross metal frame includes a cross bottom plate and a support column; after the antenna element applies a high-frequency signal to generate a radiated electromagnetic wave, the radiated electromagnetic wave will generate an induced current at the support column. The induced current flowing through the support column makes the support column constitute an inductor, and the adjacent cross bottom plates constitute a capacitor due to the gap effect. This design enables multiple cross metal frames to form a working mechanism similar to an LC filter array, showing a unique surface wave propagation stop band, which can filter the coupled signals between adjacent antenna elements and improve the performance of the array antenna. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 is an exploded diagram of a miniaturized decoupling array antenna provided in an embodiment of the present application; Figure 2 is a top view of a mounting plate, an antenna element and a cross metal frame provided in an embodiment of the present application; Figure 3 is a top view of an antenna element with a linear slow-wave patch array provided in an embodiment of the present application; Figure 4 yes Figure 3 Sectional view along line AA; Figure 5 It is a top view of an antenna element with a staggered dot matrix slow-wave patch array provided in an embodiment of the present application; Figure 6 is a schematic diagram of the structure of a cross metal frame provided in an embodiment of the present application; Figure 7 It is a partial arrangement schematic diagram of a cross metal frame provided in an embodiment of the present application; Figure 8 This is a schematic diagram of an antenna standing wave provided in an embodiment of the present application; Fig. 9 It is a gain pattern of the center frequency point of an array antenna provided in an embodiment of the present application.

[0020] Throughout the drawings, the same reference numerals are used to denote the same elements or structures, wherein: 1. Mounting plate; 2. Antenna element; 2-1. Base plate; 2-2. Ground plate; 2-3. Radiating patch; 2-4. Slow-wave patch; 3. Cross metal frame; 3-1. Cross bottom plate; 3-2. Support column; 4. Radome; 10. Gap; 20. Gap channel. DETAILED DESCRIPTION

[0021] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0022] The following is combined with Figure 1-Figure 9 This application is described in further detail.

[0023] The present application embodiment discloses a miniaturized decoupling array antenna. Figure 1-Figure 7 The miniaturized decoupling array antenna comprises a mounting plate 1, an antenna element 2 and a cross metal frame 3, wherein: a plurality of antenna elements 2 are arrayed on the surface of the mounting plate 1, the antenna element 2 comprises a substrate 2-1, a ground plate 2-2 is arranged on the surface of the substrate 2-1 facing the mounting plate 1, a radiation patch 2-3 and a slow-wave patch 2-4 are arranged on the surface of the substrate 2-1 away from the mounting plate 1, and the slow-wave patch 2-4 is distributed around the radiation patch 2-3 to form a slow-wave structure; a plurality of cross metal frames 3 are arranged on the surface of the mounting plate 1, and are cross-arranged between the plurality of antenna elements 2 to form a cross decoupling belt.

[0024] Under this design, when a high-frequency signal is applied to the antenna element 2, the radiation patch 2-3 will generate an induced current and an induced electric field on the surface. The induced electric field will propagate along the edge of the radiation patch 2-3 and form a current distribution at the end of the radiation patch 2-3. The current distribution will generate a radiation magnetic field, thereby generating a radiated electromagnetic wave.

[0025] Based on this radiation characteristic, since the multiple slow-wave patches 2-4 in the present design can form a slow-wave structure, the equivalent dielectric constant of the transmission medium is changed through the slow-wave structure, or the equivalent magnetic permeability of the transmission medium is changed to reduce the propagation speed of the electromagnetic wave, which makes the wavelength of the electromagnetic wave in the working frequency band decrease as the propagation speed decreases; in addition, the slow-wave patch 2-4 designed in the present design scheme can form a strong distributed capacitance C between the ground plate 2-2, which is equivalent to increasing the equivalent dielectric constant of the dielectric substrate 2-1, thereby reducing the phase velocity of the electromagnetic wave and shortening the wavelength, which makes the structural size of the array antenna can be greatly reduced without changing the electromagnetic characteristics of the antenna.

[0026] On this basis, the cross metal frames 3 cross-arranged on the surface of the mounting plate 1 will form a cross decoupling belt, which can effectively reduce the strong mutual coupling of the antenna elements 2 on the mounting plate 1, suppress the surface waves caused by the close arrangement of the antenna elements 2, thereby reducing the reverse radiation and improving the antenna gain, ensuring the performance of the antenna element 2, and making the antenna radiation pattern of the antenna not easy to be deformed when the installation size is limited, which can solve the high performance indicator requirements for high gain of the array antenna in complex carrier, common aperture, integration, miniaturization and other installation environments.

[0027] Under this design, this design scheme is not only applicable to the needs of aircraft and other carrier communication systems for miniaturized decoupled circularly polarized array antennas, but also applicable to the special usage needs of ground and vehicle-mounted carrier communication systems.

[0028] Furthermore, in some embodiments, Figure 3-Figure 4 As shown, the surface of the substrate 2-1 facing the mounting board 1 (i.e., the back side of the substrate 2-1) is photolithographically prepared as a ground plane 2-2 (usually, the ground plane 2-2 is formed by copper plating on the entire surface). Figure 4 , Figure 5 As shown, a surface of the substrate 2-1 facing away from the mounting plate 1 (ie, the front surface of the substrate 2-1) is photolithographically prepared with a radiation patch 2-3 and a slow-wave patch 2-4.

[0029] In some embodiments, the radiation patch 2 - 3 is a square patch, and the front side of the radiation patch 2 - 3 is preferably square.

[0030] In some embodiments, the slow-wave patch 2-4 is a small "mouth"-shaped patch, which is a square patch, and its front side is preferably square.

[0031] As a preferred example, Figure 3 As shown, in some embodiments, the slow-wave patches 2-4 are arranged in a linear array along the side length of the radiating patch 2-3 to form a linear patch array. In the circumferential direction of the radiating patch 2-3, multiple patch arrays are roughly ring-shaped, and multiple slow-wave patches 2-4 are arranged at intervals.

[0032] Furthermore, the two patch arrays located on the adjacent two sides of the radiation patch 2-3 leave a gap 10 at the edge corner of the radiation patch 2-3. By setting the gap 10, the slow-wave patches 2-4 on both sides can be separated to avoid the overlapping and failure of the effects of the slow-wave patches 2-4 (when overlapping, the miniaturization effects affecting each side of the radiation patch 2-3 will cancel each other out).

[0033] As a preferred example, Figure 5 As shown, in some embodiments, a plurality of linear patch arrays are provided on each side of the radiation patch 2-3, and the plurality of linear patch arrays are staggered; that is, the slow-wave patch 2-4 is arranged in a staggered lattice on the side of the radiation patch 2-3 to form a lattice-shaped patch array.

[0034] Under this design, multiple rows and columns of staggered slow-wave patches 2-4 are arranged on each side of the radiation patch 2-3, which can effectively improve the effect of the distributed capacitor C and enhance the overall effect of the array antenna.

[0035] Furthermore, two patch arrays located on two adjacent sides of the radiation patch 2 - 3 form a gap channel 20 of equal width at the edge corners of the radiation patch 2 - 3 , and the gap channel 20 extends along the diagonal line of the radiation patch 2 - 3 .

[0036] Further, such as Figure 6 and Figure 7As shown, the cross metal frame 3 includes a cross bottom plate 3-1 and a support column 3-2 arranged at the center of the top surface of the cross bottom plate 3-1, and the cross bottom plate 3-1 and the support column 3-2 are both made of metal. Preferably, the cross metal frame 3 is periodically arranged in a cross shape between multiple antenna elements 2. The cross metal frame 3 is grounded.

[0037] Under this design, multiple cross metal frames 3 can exhibit a unique surface wave propagation stop band, which is mainly manifested as follows: after the antenna element 2 applies a high-frequency signal to generate a radiated electromagnetic wave, the radiated electromagnetic wave will generate an induced current at the support column 3-2. The induced current flowing through the support column 3-2 makes the support column 3-2 constitute an inductor L, and the adjacent metal cross base plate 3-1 constitutes a capacitor C due to the gap effect. This design enables the multiple cross metal frames 3 to form a working mechanism similar to an LC filter array, which can filter the coupled signals between adjacent antenna elements 2 and improve the performance of the array antenna.

[0038] In some embodiments, the cross metal frame 3 is distributed in a staggered lattice between two adjacent antenna elements 2 . This design can enhance the decoupling effect and hinder the electromagnetic coupling between adjacent antenna elements 24 .

[0039] In some embodiments, Figure 2 As shown, the cross metal frames 3 are cross-distributed in a single row and a single column at the center of the cross area surrounded by multiple antenna elements 2, and the extension direction of the row and column is preferably consistent with the side length direction of the radiation patch 2-3. Under this design, the cross metal frames 3 are arranged in a single row and a single column in the central area, which can achieve a simplified and symmetrical design of the antenna while ensuring the performance of the array antenna, and reduce the amount of the cross metal frames 3.

[0040] Of course, in some embodiments, in the cross area surrounded by the antenna elements 2, a single row of cross metal frames 3 and a single column of cross metal frames 3 may be crossed to form a cross-shaped distribution according to the trajectory setting of the cross area; or, multiple rows of cross metal frames 3 may be taken as a group, multiple columns of cross metal frames 3 may be taken as a group, and the two groups of crosses may be crossed to form a cross-shaped distribution.

[0041] Furthermore, in some embodiments, the cross metal frame 3 and the mounting plate 1 are tightly fitted together into a whole through welding.

[0042] Further, such as Figure 1 As shown, in some embodiments, the array antenna further includes a radome 4 , which is fixed to the mounting plate 1 , and covers the antenna element 2 and the cross metal frame 3 .

[0043] Furthermore, in some embodiments, the antenna is fed by two equal-amplitude excitations with a phase difference of 90° to excite circularly polarized waves to output radio frequency communication signals. That is, the antenna is fed by two equal-amplitude excitations with a phase difference of 90°, and the excitation signal is transmitted to the radiation patch 2-3 through two feeding probes, and finally the excitation signal is radiated through circularly polarized electromagnetic waves.

[0044] like Figure 2 As shown, in this design, four antenna elements 2 are provided and are arranged at the four corners of the mounting plate 1. Three rows of staggered ground cross metal frames 3 are arranged between adjacent antenna elements 2, and only a single row and a single column of crosses are arranged in the center area. There is an air cavity between the radome 4 and the mounting plate 1. The radome 4 and the mounting plate 1 are tightly fitted together as a whole by screws, and the antenna element 24 and the mounting plate 12 are tightly fitted together as a whole by screws.

[0045] It can be known that, in other embodiments, the antenna elements 2 can also be arranged in nine pieces, sixteen pieces, or any other feasible array arrangement number.

[0046] In some specific embodiments, the substrate 2-1 has a thickness of H1 and a side length of L1. The side length of the radiation patch 2-3 is L2. The slow-wave patches 2-4 are distributed on the four sides of the radiation patch 2-3 according to a certain rule, and each side has N rows of periodic slow-wave patches 2-4, and the side length of the slow-wave patches 2-4 is L3.

[0047] Further, the multiple slow-wave patches 2-4 located on the same side of the radiation patch 2-3 and arranged along the side length of the radiation patch 2-3 are regarded as one row, and the number of the multiple rows of slow-wave patches 2-4 from the center of the substrate 2-1 to the outside is M1, ..., M N The spacing between the slow-wave patches 2-4 in each row (i.e., each patch array) is L4, the spacing between rows is L5, and the spacing between the slow-wave patches 2-4 and the radiation patches 2-3 in the first row from the inside to the outside is L6. In actual design and application, by changing the dimensions L3, L4, L5, L6, N, M1, ..., M N These parameters can realize the miniaturized design / adjustment of the antenna element 24.

[0048] Furthermore, the thickness of the cross bottom plate 3-1 in the cross metal frame 3 is H2, the side lengths of the cross metal frame 3 are L7 and L8, and the height of the support column 3-2 in the cross metal frame 3 is H3 and the diameter is R1. In addition, the spacing between each row of cross metal frames 3 is L9. By changing the parameters of dimensions H2, H3, R1, L7, L8, and L9, the decoupling performance between antenna array elements can be adjusted.

[0049] Example: In this embodiment, the antenna operating frequency band is L band. The substrate 2-1 is made of a material with a dielectric constant of preferably 3.5, and the length and width L1×L1 of the substrate 2-1 are preferably 38mm×38mm, and the thickness H1 is preferably 5mm.

[0050] The length and width L2×L2 of the radiation patch 2-3 are preferably 28.8mm×28.8mm; the number of rows N of the slow-wave patches 2-4 is preferably 3, the spacing L5 between each row is preferably 0.15mm, the spacing between the slow-wave patches 2-4 and the radiation patches 2-3 is L6, which is preferably 0.9mm, the side length of the slow-wave patches 2-4 is L3, which is preferably 0.7mm, the spacing L4 between each row of slow-wave patches 2-4 is preferably 1.0mm, and in the number of each row, M1 is preferably 16, M2 is preferably 17, and M3 is preferably 18.

[0051] The spacing L9 between the periodically cross-arranged cross metal frames 3 is preferably 8mm, the thickness H2 of the cross metal frame 3 is preferably 1mm, the side length L7 of the cross metal frame 3 is preferably 6m, L8 is preferably 2mm, the height H3 of the support column 3-2 of the cross metal frame 3 is preferably 6mm, and the diameter R1 of the support column 3-2 of the cross metal frame 3 is preferably 1mm; the radiation surface, ground surface, feed line and via are all made of copper-plated material, and the thickness is preferably 0.018mm. The above parameter indicators can be modified and optimized for other working frequency band requirements.

[0052] Under this design, the antenna array element patch size is reduced by about 30% compared to the non-miniaturized state. For ease of understanding, Figure 8-Figure 9 The schematic diagram of the simulation results of the electrical performance of the array antenna in the carrier simulation environment is shown. Figure 8 This is a schematic diagram of the antenna standing wave. The standing wave bandwidth with a standing wave less than 2 reaches 10.5%. It can be seen that the antenna standing wave characteristics are still good after miniaturization. Fig. 9 This is the gain pattern at the center frequency point within the working frequency band. The maximum gain is about 7dBi, and there is no obvious distortion in the pattern. This shows that the array element pattern of the array antenna has good symmetry after the decoupling design, which meets the actual use requirements.

[0053] It should be understood that expressions such as "include" and "may include" used in this application indicate the existence of the disclosed functions, operations or constituent elements, and do not limit one or more additional functions, operations and constituent elements. In this application, terms such as "include" and / or "have" may be interpreted as indicating specific characteristics, numbers, operations, constituent elements, components or combinations thereof, but may not be interpreted as excluding the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components or combinations thereof.

[0054] It should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present application.

[0055] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.

[0056] In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0057] It will be easily understood by those skilled in the art that the above description is only a preferred embodiment of the present application and is not intended to limit the present application. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present application shall be included in the scope of protection of the present application.

Claims

1. A miniaturized decoupled array antenna, characterized in that: It comprises a mounting plate (1), an antenna element (2) and a cross metal frame (3), wherein: A plurality of antenna elements (2) are distributed in an array on the surface of the mounting plate (1), and the antenna element (2) comprises a substrate (2-1), a surface of the substrate (2-1) facing the mounting plate (1) being provided with a ground plate (2-2), and a surface of the substrate (2-1) facing away from the mounting plate (1) being provided with a radiation patch (2-3) and a slow-wave patch (2-4), and the slow-wave patch (2-4) is distributed around the radiation patch (2-3) to form a slow-wave structure; A plurality of cross metal frames (3) are arranged on the surface of the mounting plate (1), and are arranged in a cross shape between the plurality of antenna elements (2) to form a cross decoupling belt.

2. The miniaturized decoupled array antenna according to claim 1, characterized in that: The slow-wave patches (2-4) are arranged in a linear array along the side length of the radiating patches (2-3) to form a linear patch array.

3. The miniaturized decoupled array antenna according to claim 2, characterized in that: Two patch arrays located on two adjacent sides of the radiation patch (2-3) maintain a gap (10) at the edge corners of the radiation patch (2-3).

4. The miniaturized decoupled array antenna according to claim 1, characterized in that: The slow-wave patches (2-4) are arranged in a staggered lattice on the side of the radiation patches (2-3) to form a lattice-shaped patch array.

5. The miniaturized decoupled array antenna according to claim 4, characterized in that: Two patch arrays located on adjacent two sides of the radiation patch (2-3) form a gap channel (20) at the edge corner of the radiation patch (2-3), and the gap channel (20) extends along the diagonal line of the radiation patch (2-3).

6. The miniaturized decoupled array antenna according to claim 1, characterized in that: The slow-wave patch (2-4) and / or the radiation patch (2-3) are square patches.

7. The miniaturized decoupled array antenna according to any one of claims 1 to 6, characterized in that: The cross metal frame (3) comprises a cross bottom plate (3-1) and a support column (3-2) arranged at the center of the top surface of the cross bottom plate (3-1).

8. The miniaturized decoupled array antenna according to any one of claims 1 to 6, characterized in that: The cross metal frames (3) are distributed in a staggered dot matrix between two adjacent antenna elements (2).

9. The miniaturized decoupled array antenna according to any one of claims 1 to 6, characterized in that: The cross metal frames (3) are cross-distributed in a single row and a single column at the center of the cross area surrounded by the antenna elements (2).

10. The miniaturized decoupled array antenna according to any one of claims 1 to 6, characterized in that: The antenna also comprises an antenna cover (4), wherein the antenna cover (4) is fixed to the mounting plate (1) and covers the antenna element (2) and the cross metal frame (3).

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