Radiation structure for dual-polarized radiation device and dual-polarized radiation device

Abstract

The invention discloses a high-isolation dual-polarized radiation device with a spatial filtering function, and the device comprises a radiation structure which comprises a dielectric plate and four radiation arms disposed on the dielectric plate, the middle part of the dielectric plate is provided with an upper strip-shaped jack, the number of the radiation arms is four, the radiation arms are distributed in a cross shape, two collinear radiation arms form a polarized radiation unit, and the radiation unit is connected with the dielectric plate. The radiation arm comprises a U-shaped first branch knot located on the upper side of the dielectric plate, a second branch knot located on the lower side of the dielectric plate, and an isolation tuning piece located in a U-shaped opening of the first branch knot, and the first branch knot and the second branch knot are coupled through a medium; a support base; and a feed balun structure. The antenna unit has a spatial filtering function due to the specific wide and narrow structures of the radiation arms, is applied to a multi-frequency high-integration antenna, can reduce coupling with a high-frequency antenna unit, and has the characteristic of low cost compared with a traditional implementation mode.

Description

[0001] The present invention is a divisional application of the Chinese invention patent application with application date of April 11, 2022, application number 2022103714563, and name “High-isolation dual-polarization radiation device with spatial filtering function”. Technical Field

[0002] The invention belongs to the field of mobile communication antennas, and in particular relates to a high-isolation dual-polarization radiation device with a spatial filtering function. Background Art

[0003] With the continuous evolution of mobile communication technology, operators need to operate multiple standards and multiple frequency bands at the same time, which has led to increasingly tight base station antenna resources. Multi-frequency and highly integrated antennas can significantly improve the utilization of the antenna radiation aperture, thereby reducing the size of the antenna and reducing the construction cost of the base station. However, with the increase in antenna integration, the strong mutual coupling between high- and low-frequency antennas will deteriorate the radiation characteristics of the antenna itself, thereby deteriorating the performance of the communication system. Therefore, the development of high-performance radiating antenna units with weak mutual coupling has become an important focus for antenna designers. Summary of the invention

[0004] The purpose of the present invention is to provide a high-isolation dual-polarization radiation device with a spatial filtering function, which has a spatial filtering effect and can reduce the mutual coupling effect with a high-frequency antenna unit in a multi-frequency high-integration antenna.

[0005] To achieve the above object, the technical solution adopted by the present invention is: a high-isolation dual-polarization radiation device with spatial filtering function, which comprises:

[0006] A radiation structure, comprising a dielectric plate, a radiation arm arranged on the dielectric plate, an upper strip-shaped jack being arranged in the middle of the dielectric plate, four radiation arms being arranged in a cross shape, two collinear radiation arms forming a polarized radiation unit, the radiation arm comprising a first branch located on the upper side of the dielectric plate and in a U shape, a second branch located on the lower side of the dielectric plate, and an isolation tuning plate located in the U-shaped opening of the first branch, wherein the first branch and the second branch are coupled through a dielectric;

[0007] A supporting base, comprising a base dielectric plate, a base feeding microstrip line formed by copper cladding and arranged on the front side of the base dielectric plate, and a signal ground formed by copper cladding and arranged on the back side of the base dielectric plate;

[0008] The feeding balun structure has upper and lower ends connected to the radiation structure and the supporting base respectively, and the upper end is connected to the dielectric plate through the upper strip-shaped jack and is electrically connected to the radiation structure.

[0009] Optimally, the first branch node includes a triangular inner end portion, two outer extension portions extending outward from the inner end portion, and the outer extension portion includes a narrow width section and a wide width section having a width greater than the narrow width section.

[0010] Optimally, the second branch comprises an outer end portion located on the outside and a middle extension portion extending inward in a bent shape.

[0011] Optimally, the isolation tuning piece is T-shaped.

[0012] Optimized, the feeding balun structure includes a first balun plate and a second balun plate which are cross-connected, the upper and lower ends of the first balun plate and the second balun plate are respectively provided with protrusions which are plugged into the supporting base and the dielectric plate, the lower half of the first balun plate is provided with a first plug-in groove, and the upper half of the second balun plate is provided with a second plug-in groove, and the first balun plate and the second balun plate are plugged together through the first plug-in groove and the second plug-in groove to form a cross structure.

[0013] Furthermore, the first balun includes a first PCB dielectric board, a first feeding microstrip line arranged on the front side of the first PCB dielectric board and extending upward from the lower end, a copper clad layer arranged on the back side of the first PCB dielectric board and parallel to each other, and a first soldering pad arranged on the front side of the first PCB dielectric board and located at the lower end of the first feeding microstrip line, and the first feeding microstrip line has a first middle section horizontally arranged above the first clamping groove.

[0014] Furthermore, the second balun includes a second PCB dielectric board, a second feeding microstrip line arranged on the front side of the second PCB dielectric board and extending upward from the lower end, a copper clad layer arranged on the back side of the second PCB dielectric board and parallel to each other, and a second solder pad arranged on the front side of the second PCB dielectric board and located at the lower end of the second feeding microstrip line, and the second feeding microstrip line has a second middle section horizontally arranged below the second clamping groove.

[0015] Furthermore, the base dielectric plate is provided with lower strip jacks corresponding to the upper strip jacks one by one, wherein two perpendicular lower strip jacks are respectively adjacent to two base feeding microstrip lines provided on the base dielectric plate.

[0016] Due to the application of the above technical scheme, the present invention has the following advantages compared with the prior art: the specific width and narrow structure of the radiating arm enables the antenna unit to have the function of spatial filtering, and is applied to multi-frequency high-integration antennas to reduce its coupling with the high-frequency antenna unit; the second branch is loaded at the end of the first branch of the radiating arm, and the two branches are coupled through the medium, which expands the width of the antenna working frequency band; by loading the tuning plate in the U-shaped first branch, the isolation between the two polarizations of the antenna unit is improved; the radiation structure of the antenna unit is realized by plastic clips and sheet metal technology, which has the characteristics of low cost compared with traditional implementation methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Attached Figure 1 is a three-dimensional diagram of the device;

[0018] Attached Figure 2 is a schematic diagram of the radiation structure;

[0019] Attached Figure 3 This is the rear view of the first balun;

[0020] Attached Figure 4 This is the main view of the first balun;

[0021] Attached Figure 5 This is the rear view of the second balun;

[0022] Attached Figure 6 This is the main view of the second balun;

[0023] Attached Figure 7 A top view of the support base;

[0024] Attached Figure 8 A bottom view of the support base;

[0025] Attached Fig. 9 is a top view of the radiation arm;

[0026] Attached Fig.10 A three-dimensional diagram of the radiating arm. DETAILED DESCRIPTION

[0027] The present invention will be further described below in conjunction with the embodiments shown in the accompanying drawings.

[0028] like Figure 1 As shown, the radiation device in the present invention includes a radiation structure 1, a feeding balun structure 2, and a supporting base 3. It is worth noting that Figure 1 The radiation device in the figure is only a specific implementation form of the present invention. Based on the content of the present invention, it also has other possible implementation structures, especially the specific implementation method of the radiation structure 1.

[0029] like Figure 2As shown, the radiation structure is mainly composed of four rotationally symmetrical radiation arms and a dielectric plate supporting the radiation arms. The four radiation arms are radiation arm 101, radiation arm 102, radiation arm 103 and radiation arm 104 in the dotted box in the figure. Among them, the radiation arm 101 and the radiation arm 103 are on the same straight line, forming a polarized radiation unit; the radiation arm 102 and the radiation arm 104 are on the same straight line, forming another polarized radiation unit, and the placement direction is perpendicular to the center line of the radiation arm 101 and the radiation arm 103. If one of the radiation units is defined as +45° polarization, the other is -45° polarization.

[0030] Specifically, the radiation structure includes:

[0031] The dielectric plate 105 is mainly used to support four radiation arms, namely radiation arms 101 , 102 , 103 and 104 , and its shape can be a square or a cross structure.

[0032] Taking the radiation arm 101 as an example, it includes:

[0033] The first branch 111 is located on the upper side of the dielectric plate 105 and has a U-shaped structure; the second branch 112 is located on the lower side of the dielectric plate 105; and the isolation tuning plate is located in the middle of the opening of the U-shaped first branch.

[0034] Four strip-shaped jacks 114 are located in the middle of the entire dielectric board and are used to fix the radiation structure and the feeding balun structure and provide a path for electrical connection.

[0035] The filtering function of the present invention is realized by using a U-shaped metal structure to realize the first branch, which and the second branch both have a wide and narrow structure, forming a specific spatial filtering characteristic, allowing high-frequency electromagnetic waves to pass through the radiation structure well. This filtering function can reduce the mutual coupling between it and the high-frequency radiation unit in the multi-frequency antenna.

[0036] The bandwidth broadening of the present invention is achieved by dividing each radiating arm in each radiating unit into two sections (i.e., a first branch and a second branch), and the two branches are respectively located on both sides of the dielectric plate 105. The two branches are coupled through the dielectric, which can improve the filtering effect and broaden the working frequency bandwidth of the antenna radiation.

[0037] The high isolation characteristic of the present invention is achieved by using a U-shaped metal structure to realize the first branch, placing a metal tuning piece in the U-shaped opening, and arranging a T-shaped isolation tuning piece in the middle of the opening of the U-shaped first branch to obtain a high isolation characteristic. Specifically, Figure 9-10As shown, the first branch 111 includes a triangular inner end 1113, two extensions extending outward from the inner end, the extension includes a narrow section 1112 and a wide section 1111 whose width is greater than the narrow section; the second branch 112 includes an outer end 1122 located on the outside, a middle section extension 1120 that is bent and symmetrically arranged on the outer end 1122 and extends inward, and an inner end 1123 connected to the inner end of the middle section extension 1120, each of the middle section extensions 1120 includes an elongated inner extension middle section 1121 that is arranged along the direction from the first branch to the second branch, and a wide section 1111. 23 is coupled with the wide section 1111 through the dielectric plate 105; the length of the wide section 1123 of the second branch is slightly smaller than the length of the wide section 1111 of the first branch; the T-shaped isolation tuning plate includes a front side section and a rear side section wider than the front side section, the edge of the front side section close to the outer end 1122 is the front edge B, the edge of the wide section 1111 close to the narrow section 1112 is the rear edge A, and the front edge B is flush with the rear edge A; the spacing of the inner extended middle section 1121 is c, the spacing of the wide section 1111 is d, the length of the front edge B is e, c<e<d, which can greatly improve the isolation characteristics.

[0038] The antenna unit of the present invention is realized at low cost: the radiation arm is realized by using a sheet metal process, thereby reducing the cost.

[0039] like Figure 1 As shown in the figure, the feeding balun structure consists of two cross-shaped balun plates. It has two functions: one is to fix and support the entire radiation structure, and the other is to feed the two radiation units in a balanced manner. The height of the feeding balun structure is approximately one-quarter of the wavelength corresponding to the central operating frequency of the antenna unit.

[0040] Specifically

[0041] The structures of the first balun plate 20 and the second balun plate 21 are respectively as follows: Figure 3-Figure 6 Each balun sheet has protrusions at both ends, the upper end is used to insert into the upper strip-shaped plug hole 114 of the radiation structure, and the lower end is used to insert into the lower strip-shaped plug hole 304 on the supporting base. The balun sheet is implemented by a double-sided copper-clad PCB board.

[0042] Taking the first balun as an example, its specific structure includes:

[0043] 1. A first PCB dielectric plate 205;

[0044] 2. Two copper-clad layers on the back of the first PCB dielectric board 205, such as Figure 3 The copper clad layer 201 and the copper clad layer 202 are parallel to each other and are not in direct physical contact.

[0045] 3. The feeding microstrip line on the front side of the first PCB dielectric plate 205, such as Figure 4 One end of the first feeding microstrip line 203 has a first soldering pad 204, which is the soldering position for soldering with the base feeding microstrip line 301 on the supporting base, and the other end is open. The microstrip line at the soldering pad end and the microstrip line at the open end are respectively located above the copper clad layer 201 and the copper clad layer 202 on the back of the PCB board. In other words, the total microstrip line on a single balun sheet spans over the top of two physically separated copper clad layers, coupling electromagnetic energy to the two copper clad layers. The two copper clad layers are electrically connected to the two radiating arms of the radiating unit, and the electromagnetic energy radiates electromagnetic waves into space through the radiating structure.

[0046] like Figure 5-6 As shown, the second balun plate also has a similar structure. The difference is that the second feeding microstrip line 213 bypasses below the second clamping groove 216, and the first balun plate 20 and the second balun plate 21 have a first clamping groove 206 and a second clamping groove 216 in the middle, respectively. Through the first clamping groove 206 and the second clamping groove 216, the two balun plates are plugged together to finally form Figure 1 The cross-fed balun structure is shown.

[0047] The feed balun is fixed on the support base by insertion and welding. The support base is also made of a double-sided copper-clad PCB. Figure 7-8 As shown, its specific structure includes: a base dielectric plate 302, and a signal ground 303 of a base feeding microstrip line 301 arranged on the back of the base dielectric plate 302. Two polarized base feeding microstrip lines 301 are located on the front of the base dielectric plate 302, one end of which is connected to the coaxial cable, and the other end is located near the jack. When the feeding balun sheet is inserted into the square jack on the supporting base, the first pad 204 and the second pad 214 on the feeding balun are electrically connected to the base feeding microstrip line 301 by welding.

[0048] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A radiation structure for a dual-polarization radiation device, Features: It includes a dielectric plate, a radiation arm arranged on the dielectric plate, the radiation arm includes a first branch located on the upper side of the dielectric plate and in a U shape, a second branch located on the lower side of the dielectric plate, and an isolation tuning plate located in the U-shaped opening of the first branch, the first branch and the second branch are coupled through a dielectric; The first branch node includes a triangular inner end portion, two outer extension portions extending outward from the inner end portion, and the outer extension portion includes a narrow width section and a wide width section having a width greater than the narrow width section; The second branch node includes an outer end portion located at the outer side, and a middle section extension portion extending inward in a bent shape, and each of the middle section extension portions includes an elongated inner middle section arranged along the direction from the first branch node to the second branch node; The isolation tuning piece is T-shaped and is arranged in the middle position of the opening of the first branch of the U-shape. The T-shaped isolation tuning piece includes a front side section and a rear side section wider than the front side section. The edge of the front side section close to the outer end is the front edge, and the edge of the wide section close to the narrow section is the rear edge. The front edge and the rear edge are flush; the spacing of the inner extended middle section is c, the spacing of the wide section is d, the length of the front edge is e, and c<e<d.

2. The radiation structure for a dual-polarization radiation device according to claim 1, Features: An upper strip-shaped plug hole is arranged in the middle of the medium plate.

3. The radiation structure for a dual-polarization radiation device according to claim 1, Features: There are four radiation arms distributed in a cross shape.

4. The radiation structure for a dual-polarization radiation device according to claim 3, Features: The two collinear radiation arms constitute a polarized radiation unit.

5. A dual-polarization radiation device, comprising a radiation structure, a support base and a feeding balun structure, Features: The radiation structure is the radiation structure described in any one of claims 1-4.

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