Patch antennas and antenna arrays

Abstract

The present invention provides a patch antenna, which at least includes a feeding structure, a support member and a near-field coupling plate; the support member is fixed on the feeding structure, and the near-field coupling plate is fixed on the support member; the edge of the near-field coupling plate is provided with at least one pair of symmetrical slots. The present invention also provides an antenna array having at least one patch antenna. Thereby, the present invention can significantly improve antenna isolation, enhance the S parameters of the patch antenna in the array, and will not affect the directional pattern index.

Description

Technical Field

[0001] The present invention relates to the technical field of mobile antennas, and in particular to a patch antenna and an antenna array. Background Art

[0002] As the construction of 5G communication systems around the world begins, various operators have successively used base stations and antennas in the 3.5GHz frequency band. Due to its frequency coverage characteristics, the 3.5GHz base station deployment that matches it is generally relatively small, and the base station + antenna method is used, which makes the antenna thickness relatively low. Due to the restrictions on antenna thickness, low-profile units are often used for antenna units, and patch antennas are usually used as the first choice.

[0003] Existing patch antennas usually have direct feeding and coupled feeding methods, that is, direct feeding through probes and microstrip lines is called direct feeding; and coupled feeding is performed by coupling the feeding plate and the radiating plate. After the existing patch antennas are formed into antenna arrays, their impedance characteristics and polarization isolation are usually seriously deteriorated due to problems with the surrounding environment (small unit spacing), which causes great difficulties in the design and use of antenna arrays. The main manifestations are the difficulty of standing wave matching, the serious deterioration of antenna isolation, and the poor S parameters of the array. At this time, some metal parts need to be added to the antenna array to debug the isolation, but for the frequency of 3.5GHz, the size and position of the debugging parts are slightly deviated, and the difference is also relatively large, resulting in low production and debugging efficiency of the antenna.

[0004] In summary, the prior art obviously has inconveniences and defects in practical use, so it is necessary to improve it. Summary of the invention

[0005] In view of the above-mentioned defects, the object of the present invention is to provide a patch antenna and an antenna array, which can significantly improve the antenna isolation, enhance the S parameters of the patch antenna in the array, and will not affect the radiation pattern indicators.

[0006] In order to achieve the above-mentioned purpose, the present invention provides a patch antenna, which at least includes a feeding structure, a support member and a near-field coupling plate; the support member is fixed on the feeding structure, and the near-field coupling plate is fixed on the support member; the edge of the near-field coupling plate is provided with at least one pair of symmetrical grooves.

[0007] The patch antenna according to the present invention further comprises a director plate, wherein the director plate is fixed above the near-field coupling plate and is jointly supported by the supporting member.

[0008] According to the patch antenna of the present invention, the near-field coupling plate and the director plate are in an axisymmetric and centrosymmetric structure.

[0009] According to the patch antenna of the present invention, the near-field coupling piece is circular, square, diamond or polygonal; and / or

[0010] The guide piece is in a cross shape, a square shape or a circle shape.

[0011] According to the patch antenna of the present invention, the support member is detachably connected to the feeding structure, and the near-field coupling plate and the director plate are respectively connected to the support member.

[0012] According to the patch antenna of the present invention, the near-field coupling plate is divided into a plurality of petal-shaped structures by the slots, and the petal-shaped structures are planar or non-planar.

[0013] According to the patch antenna of the present invention, the petal-shaped structures of the near-field coupling plate are bent downward at the same angle.

[0014] According to the patch antenna of the present invention, two pairs of symmetrical slots are provided on the edge of the near-field coupling plate, and the four slots are distributed in a cross shape.

[0015] According to the patch antenna of the present invention, the near-field coupling plate is suspended above the feeding structure through the support member, and a gap is maintained between the near-field coupling plate and the feeding structure; and / or

[0016] The feeding structure is a PCB feeding structure, comprising a microstrip antenna, a PCB substrate and a feeding line.

[0017] The present invention also provides an antenna array, comprising at least one of the patch antennas and a feeding network structure as described above, wherein the patch antenna is fixed on the feeding network structure.

[0018] The patch antenna of the present invention at least includes a feeding structure, a support and a near-field coupling plate. By setting at least a pair of symmetrical slots on the edge of the near-field coupling plate, the surface current flow direction is changed, thereby achieving a partial reverse cancellation effect, which can significantly improve the isolation of the patch antenna in the array environment and improve the S parameters of the patch antenna in the array. Because the symmetrical structure of the coupling plate has not changed, it will not affect the directional pattern index. Better yet, the patch antenna of the present invention also includes a guide plate, which is fixed above the near-field coupling plate. By locally changing the electromagnetic field, the impedance curve can be converged, thereby achieving the purpose of optimizing the standing wave of the patch antenna and facilitating the formation of an antenna array. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic diagram of a preferred three-dimensional structure of the patch antenna of the present invention;

[0020] Figure 2 It is a preferred three-dimensional exploded schematic diagram of the patch antenna of the present invention;

[0021] Figure 3 It is a schematic diagram of a preferred structure of a near-field coupling plate of the present invention;

[0022] Figure 4 is the current flow diagram of the near-field coupling piece without slots and the near-field coupling piece with slots;

[0023] Figure 5 It is a schematic diagram of the preferred structure of the guide plate of the present invention;

[0024] Figure 6 It is a schematic diagram of a preferred structure of the support member of the present invention;

[0025] Figure 7 Schematic diagram of the structure of six near-field coupling sheets of the present invention;

[0026] Figure 8 It is a schematic diagram of the structure of three guide plates of the present invention;

[0027] Fig. 9 It is a schematic diagram of the preferred structure of the antenna array of the present invention;

[0028] Fig.10 It is a schematic diagram of a preferred decomposition of a sub-array of an antenna element of the present invention;

[0029] Fig.11 It is the impedance curve diagram of the existing patch antenna;

[0030] Fig.12 is an impedance curve diagram of the patch antenna of the present invention;

[0031] Fig.13 is the isolation curve of the existing patch antenna;

[0032] Fig.14 is an isolation curve diagram of the patch antenna of the present invention;

[0033] Fig.15 is the horizontal plane radiation pattern of the existing patch antenna;

[0034] Fig.16 It is the horizontal plane radiation pattern of the patch antenna of the present invention.

[0035] Reference numerals:

[0036] Patch antenna 100; Feed structure 10; Microstrip antenna 11;

[0037] Feeder 12; Mounting hole 13; Support member 20;

[0038] Buckle 21; Near field coupling sheet 30; Slot 31;

[0039] Petal-shaped structure 32; Ungrooved near-field coupling plate 30'; Directing plate 40;

[0040] Feed network structure 200; Antenna array 300; Reflector 400. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention 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 invention and are not intended to limit the present invention.

[0042] It should be noted that references to "one embodiment", "embodiment", "example embodiment", etc. in this specification refer to the embodiment described, which may include specific features, structures or characteristics, but not every embodiment must include these specific features, structures or characteristics. In addition, such expressions do not refer to the same embodiment. Furthermore, when describing specific features, structures or characteristics in conjunction with an embodiment, whether or not there is an explicit description, it has been shown that it is within the knowledge of those skilled in the art to combine such features, structures or characteristics into other embodiments.

[0043] In addition, certain words are used in the specification and subsequent claims to refer to specific components or parts. Those with ordinary knowledge in the relevant field should understand that manufacturers can use different nouns or terms to refer to the same component or part. This specification and subsequent claims do not use differences in names as a way to distinguish components or parts, but use differences in the functions of components or parts as the criteria for distinction. "Including" and "including" mentioned throughout the specification and subsequent claims are open-ended terms and should be interpreted as "including but not limited to". In addition, the word "connected" here includes any direct and indirect electrical connection means. Indirect electrical connection means include connection through other devices.

[0044] Figure 1 and Figure 2 The preferred structure of the patch antenna of the present invention is shown, and the patch antenna 100 at least includes a feeding structure 10, a support member 20 and a near-field coupling plate 30. The support member 20 is fixed on the feeding structure 10, and the near-field coupling plate 30 is fixed on the support member 20. The edge of the near-field coupling plate 30 is provided with at least one pair of symmetrical slots 31, and the slots 31 can change the flow direction of the surface current of the patch antenna 100, thereby achieving a partial reverse cancellation effect, achieving the purpose of improving the isolation of the patch antenna 100 in the array environment, thereby optimizing the S parameter, and will not affect the directional pattern index.

[0045] like Figure 3 and Figure 4As shown, compared with the existing near-field coupling plate 30' without slots, the present invention provides symmetrical slots 31 on the near-field coupling plate 30 to change the flow direction of the surface current, thereby achieving a partial reverse cancellation effect, thereby achieving the purpose of optimizing the array isolation. Figure 4 The two arrows in the figure are the feeding direction or polarization direction. Figure 2 The directions of the microstrip antennas 11 are shown to be consistent.

[0046] Preferably, the patch antenna 100 of the present invention further includes a guide plate 40, which is fixed above the near-field coupling plate 30 and is supported by the support member 20. The guide plate 40 can locally change the field distribution through coupling current, and can converge the impedance curve within an ideal range, thereby optimizing the standing wave of the patch antenna 100 and facilitating the formation of an antenna array. The guide plate 40 is preferably made of metal material, but the material of the guide plate 40 is not limited thereto.

[0047] The patch antenna 100 of the present invention preferably uses a low-profile unit, such as Figure 1 and Figure 2 As shown, the structure is divided into a feeding structure 10 as a bottom circuit, a near-field coupling plate 30 of a middle-level guiding structure, and a guiding plate 40 of an upper-level guiding structure, which are connected by a support 20. The feeding structure 10 and the near-field coupling plate 30 ensure that the directional diagram of the patch antenna 100 is normal, and the guiding plate 40 ensures that the impedance of the patch antenna 100 can be well matched.

[0048] like Figure 1 to Figure 3 As shown, the near-field coupling sheet 30 is divided into a plurality of petal structures 32 by slots 31, and the petal structures 32 are planar or non-planar. Preferably, the petal structures 32 of the near-field coupling sheet 30 are bent downward at the same angle to form a non-planar shape, and it is obvious that the non-planar shape of the petal structures 32 of the near-field coupling sheet 30 is not limited to this structure. The slots 31 of the near-field coupling sheet 30 can effectively improve the isolation problem of the unit in the array environment.

[0049] In this embodiment, two pairs of symmetrical slots 31 are provided at the edge of the near-field coupling plate 30, and the four slots 31 are distributed in a cross shape. The near-field coupling plate 30 is divided into four petal structures 32 by the four slots 31 and is in an open state. The four petal structures 32 can be planar or non-planar and pressed downward (i.e., bent downward at the same angle). The shape of the near-field coupling plate 30 is the same as the characteristics of the microstrip antenna. By making four slots 31 on its four sides, the isolation of the patch antenna 100 after the array is formed can be changed. The reason is that after the slots 31 are made, the position of the end is changed compared with the original position. Assuming that the radiation direction of the antenna is ±45°, then by making slots 31 at 0 and 90°, the edge current end of the patch antenna 100 changes from the original outer edge to the inside. The change in current distribution after the slots 31 causes the isolation of the antenna unit to change. However, since the current distribution on the entire near-field coupling plate 30 also presents an axially symmetrical + centrally symmetrical structure, the ends cancel each other out, so it does not affect the directional pattern, such as Fig.15 and Fig.16 comparison.

[0050] Preferably, the near-field coupling plate 30 and the guide plate 40 are in an axisymmetric and center-symmetrical structure. Figure 1 to Figure 3 As shown, the near-field coupling plate 30 is preferably circular, but the shape of the near-field coupling plate 30 of the present invention is not limited thereto. Figure 7 As shown, the near-field coupling plate 30 can be circular, square, diamond or polygonal. Figure 1 , Figure 2 and Figure 5 As shown, the guide plate 40 is preferably in a cross shape, but the shape of the guide plate 40 of the present invention is not limited thereto. Figure 8 As shown, the guide plate 40 may be in a cross shape, a square shape, a circle shape, or the like.

[0051] like Figure 1 , Figure 2 and Figure 6 As shown, the support member 20 is detachably connected to the feed structure 10, and the near-field coupling plate 30 and the guide plate 40 are respectively connected to the support member 20. The near-field coupling plate 30 is suspended above the feed structure 10 through the support member 20, and a gap is maintained between the near-field coupling plate 30 and the feed structure 10. In this embodiment, the support member 20 is clamped on the feed structure 10 by the buckle 21, so it is more convenient to install and disassemble. The support member 20 is preferably made of plastic material, but obviously, the material of the support member 20 is not limited thereto.

[0052] The feeding structure 10 is preferably a PCB feeding structure 10, such as Figure 2As shown, the PCB feeding structure 10 includes a microstrip antenna 11, a PCB substrate and a feeding line 12, which together constitute the bottom microstrip antenna. In this embodiment, the feeding structure 10 is circular, but the shape of the feeding structure 10 of the present invention is not limited thereto, and the feeding structure 10 can also be square, rhombus or polygonal.

[0053] like Fig. 9 As shown, the present invention also provides an antenna array 300, the antenna array 300 includes at least one patch antenna 100 and a feed network structure 200, and the patch antenna 100 is fixed on the feed network structure 200. Preferably, the patch antenna 100 can be printed on the feed network structure 200 and electrically connected to the feed network structure 200. Preferably, the feed network structure 200 includes a feed network circuit and a reflector 400. In this embodiment, the antenna array 300 includes eight sub-arrays, each of which includes three feed structures 10, three near-field coupling plates 30, three guide plates 40, three support members 20, and a feed network structure 200. The operating frequency band of the patch antenna 100 is 3400MHz-3600MHz, and it is an antenna with ±45° polarization.

[0054] Fig.10 1 is a schematic diagram of a preferred decomposition of a subarray of an antenna array of the present invention, wherein the near-field coupling plate 30 and the guide plate 40 are fixed on the reflector 400 by the support 20 through four mounting holes 13 on the feed network structure 200, forming a 1*3 subarray. Obviously, the number of mounting holes 13 is not limited to four, and can also be any number such as two, three, or five.

[0055] It should be pointed out that there is no limit to the number of sub-arrays of the antenna array 300 of the present invention, and there is no limit to the number of patch antennas 100 in each sub-array, and both can be set arbitrarily according to actual needs.

[0056] Fig.11 is the impedance curve of the existing patch antenna. Fig.12 3 is the impedance curve of the patch antenna of the present invention. By comparing the impedance curves (standing waves) of the two after forming the antenna array 300, it can be seen that the impedance curves converge a lot and it is very easy to make a matching array.

[0057] Fig.13 is the isolation curve of the existing patch antenna. Fig.14 3 is the isolation curve of the patch antenna of the present invention. By comparing the isolation curves (standing waves) of the two after forming the antenna array 300, it can be seen that the isolation is improved by about 8 dB, thereby significantly optimizing the isolation of the patch antenna 100 in the array environment.

[0058] Fig.15is the horizontal plane radiation pattern of the existing patch antenna, Fig.16 The horizontal plane directional diagram of the patch antenna of the present invention is compared. After the directional diagrams of the two are formed into the antenna array 300, they are basically the same, indicating that the technical means of improving the S parameters such as the slot 31 and the loading of the guide plate 40 will not affect the directional diagram index.

[0059] In summary, the patch antenna of the present invention at least includes a feeding structure, a support member and a near-field coupling plate. By setting at least one pair of symmetrical slots on the edge of the near-field coupling plate, the surface current flow direction is changed, thereby achieving a partial reverse cancellation effect, which can significantly improve the isolation of the patch antenna in the array environment, improve the S parameters of the patch antenna in the array, and will not affect the directional diagram index. Better yet, the patch antenna of the present invention also includes a guide plate, which is fixed above the near-field coupling plate. By locally changing the electromagnetic field, the impedance curve can be converged, thereby achieving the purpose of optimizing the standing wave of the patch antenna and facilitating the formation of an antenna array.

[0060] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art may make various corresponding changes and modifications based on the present invention, but these corresponding changes and modifications should all fall within the scope of protection of the claims attached to the present invention.

Claims

1. A patch antenna, characterized in that: At least comprises a feeding structure, a supporting member and a near-field coupling piece; the supporting member is fixed on the feeding structure, and the near-field coupling piece is fixed on the supporting member; at least one pair of symmetrical slots are provided on the edge of the near-field coupling piece; It also includes a guide plate, which is fixed above the near-field coupling plate and is supported by the support member; The near-field coupling plate is divided into a plurality of petal-shaped structures by the slots, and the petal-shaped structures are non-planar; The petal-shaped structures of the near-field coupling plate are bent downward at the same angle; The feeding structure is a PCB feeding structure, comprising a microstrip antenna, a PCB substrate and a feeding line.

2. The patch antenna according to claim 1, characterized in that: The near-field coupling plate and the guide plate are in an axisymmetric and center-symmetrical structural shape.

3. The patch antenna according to claim 1, characterized in that: The near-field coupling plate is circular or polygonal; and / or The guide piece is in a cross shape, a square shape or a circle shape.

4. The patch antenna according to claim 1, characterized in that: The support member is detachably connected to the feeding structure, and the near-field coupling plate and the guide plate are respectively connected to the support member.

5. The patch antenna according to claim 1, characterized in that: Two pairs of symmetrical slots are arranged at the edge of the near-field coupling plate, and the four slots are distributed in a cross shape.

6. The patch antenna according to claim 1, characterized in that: The near-field coupling plate is suspended above the feeding structure through the supporting member, and a gap is maintained between the near-field coupling plate and the feeding structure.

7. An antenna array, characterized in that: It comprises at least one of the patch antennas and a feeding network structure as claimed in any one of claims 1 to 6, wherein the patch antenna is fixed on the feeding network structure.

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