An antenna with low profile dual polarized slot antenna elements

Abstract

The application belongs to the field of antenna design, and particularly discloses a kind of antennas with low profile dual-polarized slot antenna oscillator, comprising: a plurality of reflection plate is made of reflection box, and the PCB board is arranged in reflection box;PCB board is fixed in reflection box, the side of PCB board away from box bottom is provided with first feed circuit and second feed circuit;First feed circuit and second feed circuit are mutually orthogonal, and first feed circuit and second feed circuit all include at least two microstrip lines;The side of PCB board close to box bottom is provided with copper layer, and the copper layer is provided with two groups of mutually orthogonal coupling slots for radiating electromagnetic waves, and the width of coupling slot is greater than the width of any microstrip line.In the application, only one layer of PCB board is provided, the structure is more simple, the volume is more optimized, and the material is more saved;The antenna in the application has wider working bandwidth while realizing high gain and low profile, higher polarization purity of single polarized antenna, higher polarization isolation degree between different polarizations of the antenna, and is suitable for various direct feed.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of antenna elements and relates to an antenna with a low-profile dual-polarized slot antenna element. BACKGROUND

[0002] Antenna elements are generally arranged on an antenna to guide and amplify electromagnetic waves on a wire, and the electromagnetic signals received by the antenna are stronger.

[0003] Generally, the antenna array in the prior art is designed to be dual-frequency and dual-polarized. Referring to a compact high-isolation dual-frequency dual-polarized filtering antenna disclosed in Chinese Patent CN211126050U, the filtering patch antenna unit operating at a low frequency and the filtering dipole antenna unit operating at a high frequency are arranged together in the vertical direction, and the two share a reflector plate. In order to increase the isolation between antenna elements of different frequencies, the radiation apertures of antenna elements of different frequencies are generally arranged at different plane heights. According to the frequency characteristics of the physical size of the antenna element, the high-frequency element is generally located at a lower profile. Therefore, in the dual-frequency dual-polarized antenna, the low-profile characteristic of the high-frequency element is generally better than that of the low-frequency element. Therefore, in the prior art, a low-profile slot antenna is generally designed on the high-frequency element.

[0004] However, the slot antenna needs to meet multiple design requirements, such as:

[0005] 1. High gain. In order to improve the gain characteristics of the element, a long enough radiation aperture is required.

[0006] 2. High frequency bandwidth. In order to obtain a wide frequency bandwidth, an input feed circuit is required for auxiliary impedance matching.

[0007] 3. Low profile. A low-profile slot antenna is designed on the high-frequency element.

[0008] 4. High polarization isolation. Physically isolate different polarized elements to improve the polarization purity of a single polarized element; the elements of different polarizations are orthogonal in the physical direction, and the feed of the elements of different polarizations is orthogonal or isolated.

[0009] The antenna in the prior art meets the above design requirements while increasing the production cost. The main reason is that a large radiation aperture is required, but the slot size cannot be too long, otherwise the PCB size will increase, resulting in an increase in cost. Low profile needs to be achieved, but generally a balun structure is used to fix multiple components at different heights, which increases the height of the device and makes assembly difficult, resulting in an increase in production cost. SUMMARY

[0010] The application provides an antenna with a low-profile dual-polarized slot antenna element to solve the current problems.

[0011] To solve the above technical problems, the technical scheme of the present application is: the antenna with low-profile dual-polarized slot antenna element, characterized in that it comprises a reflection box composed of multiple reflection plates and a PCB board arranged in the reflection box.

[0012] The reflection box is a coverless box, comprising a box bottom and four side walls.

[0013] The PCB board is fixed in the reflection box, and the distance between the PCB board and the box bottom is at least 1 mm.

[0014] The side of the PCB board away from the box bottom is provided with a first feeding circuit and a second feeding circuit; the first feeding circuit and the second feeding circuit are orthogonal to each other, the first feeding circuit comprises at least two microstrip lines, and the second feeding circuit comprises at least two microstrip lines.

[0015] The side of the PCB board close to the box bottom is provided with a copper layer, and two groups of coupling slots for radiating electromagnetic waves are arranged on the copper layer, the coupling slots are orthogonal to each other, and the width of the coupling slots is greater than the width of any microstrip line.

[0016] In a preferred embodiment of the present application, the coupling slots include first slots, second slots, third slots and fourth slots, the first slots and the second slots are arranged on the same straight line, the third slots and the fourth slots are arranged on the same straight line, the straight line on which the first slots and the second slots are arranged is perpendicular to the straight line on which the third slots and the fourth slots are arranged; the first slots, the second slots, the third slots and the fourth slots are orthogonal to each other in sequence to generate mutually orthogonal electric fields and form a dual-polarized antenna with ±45°.

[0017] In a preferred embodiment of the present application, the first slots, the second slots, the third slots and the fourth slots have the same structure, the first slots are axisymmetric along one diagonal line of the PCB board, the first slots include a slot body, a slot head arranged at one end of the slot body close to the center of the PCB board, and a slot tail arranged at one end of the slot body away from the center of the PCB board, the slot head is arrow-shaped, and the slot tail coincides with one corner of the PCB board.

[0018] In a preferred embodiment of the present application, the first feeding circuit comprises a first thick microstrip line and a first thin microstrip line, the first thin microstrip line is arranged on the PCB board, one end of the first thick microstrip line is connected with the first thin microstrip line, and the other end of the first thick microstrip line is led out as a first cable connector.

[0019] In a preferred embodiment of the present invention, the first fine strip includes a fine head segment, a fine middle segment, and a fine tail segment connected end to end in sequence. The fine head segment is perpendicular to the location of the first gap, the fine tail segment is perpendicular to the location of the second gap, the fine middle segment has a multi-bend structure to avoid any coupling gap, one end of the fine middle segment is connected to the end of the fine head segment near the third gap, and the other end of the fine middle segment is connected to the end of the fine tail segment near the third gap.

[0020] In a preferred embodiment of the present invention, the first thick microstrip line includes a thick start section, a thick middle section and a thick end section connected end to end in sequence. One end of the thick start section is connected to the thin middle section and the other end is connected to the thick middle section. One end of the thick end section is connected to the thick middle section and the other end is led out as a first cable connector.

[0021] In a preferred embodiment of the present invention, the second power supply circuit includes a second fine microstrip line and a second coarse microstrip line. With the central axis between the first gap and the third gap as the axis of symmetry, the second fine microstrip line is axially symmetrical with the first fine microstrip line, and the intersection of the first fine microstrip line and the second fine microstrip line is orthogonal.

[0022] In a preferred embodiment of the present invention, the first and / or second fine strips are bridged at the intersection node.

[0023] In a preferred embodiment of the present invention, with the central axis between the first gap and the third gap as the axis of symmetry, the thick beginning segment and the thick middle segment of the second thick microstrip line are axially symmetrical with the thick beginning segment and the thick middle segment of the first thick microstrip line, the thick end segment of the second thick microstrip line is parallel to the thick end segment of the first thick microstrip line, one end of the thick end segment of the second thick microstrip line is connected to the thick middle segment of the second thick microstrip line, and the other end is led out as a second cable connector.

[0024] In a preferred embodiment of the present invention, a metal ring guide is further provided on one side of the PCB board near the first power supply circuit and the second power supply circuit, and the distance between the ring guide and the PCB board is at least 1 mm.

[0025] The technical solution provided by this invention has the following advantages compared with the prior art:

[0026] This invention uses only one PCB board, resulting in a simpler structure, more optimized volume, and more material savings. The antenna in this invention achieves high gain and low profile while having a wider operating bandwidth, higher polarization purity of a single polarized antenna, and higher polarization isolation between different polarizations of the antenna. It is suitable for direct feed of various 50-ohm cables (such as 141, 120, 086, etc.). Attached Figure Description

[0027] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the accompanying drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced. Obviously, the accompanying drawings in the following description only only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained from these drawings without creative labor.

[0028] Figure 1 is a schematic diagram of an antenna with a low-profile dual-polarized slot antenna element according to an embodiment of the present application;

[0029] Figure 2 is a schematic diagram of a PCB board with a copper layer on one side in an antenna with a low-profile dual-polarized slot antenna element according to an embodiment of the present application;

[0030] Figure 3 is a schematic diagram of a PCB board with a feeding circuit on one side in an antenna with a low-profile dual-polarized slot antenna element according to an embodiment of the present application;

[0031] Figure 4 is a schematic diagram of the position relationship between a feeding circuit and a coupling slot in an antenna with a low-profile dual-polarized slot antenna element according to an embodiment of the present application.

[0032] The drawings shown in the figures are:

[0033] 10 - reflector box; 101 - box bottom; 20 - PCB board; 201 - first slot; 2011 - head; 2012 - tail; 202 - second slot; 203 - third slot; 204 - fourth slot; 205 - first fine microstrip line; 2051 - fine head section; 2052 - fine middle section; 2053 - fine tail section; 206 - first thick microstrip line; 2061 - thick head section; 2062 - thick middle section; 2063 - thick tail section; 207 - first cable connector; 208 - second fine microstrip line; 209 - second thick microstrip line; 210 - second cable connector; 30 - director. DETAILED DESCRIPTION

[0034] In order to facilitate understanding, the following describes an antenna with a low-profile dual-polarized slot antenna element according to the embodiments, and it should be understood that these embodiments are only used to illustrate the present application and not to limit the scope of the present application.

[0035] In the description of the present application, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation and positional relationship shown in the drawings, and are only for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application. In addition, the terms "first", "second", "third" are only for descriptive purposes and cannot be understood as indicating or implying relative importance.

[0036] In the description of the present application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0037] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the related drawings. The preferred embodiments of the present application are shown in the drawings. However, the present application can be implemented in many different forms, and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thorough and comprehensive.

[0038] As shown in Figure 1 The present application discloses an antenna with a low-profile dual-polarized slot antenna element, which mainly comprises a reflection box 10, a PCB board 20 arranged in the reflection box 10, and a director 30 arranged on the upper part of the PCB board 20.

[0039] In the present application, only one layer of PCB board 20, that is, a double-sided substrate, is arranged, and the substrate material is selected diversely, and the material can be selected from PTFE, ceramic hydrogen, FR4, polyimide, etc., which is sufficient to meet the different cost control requirements of the market, and the structure is more simple, the volume is more optimized, and the material is more saved.

[0040] The reflection box 10 comprises a plurality of reflection plates, the cross section of which is U-shaped, comprising a box bottom 101 and a plurality of side walls.

[0041] In order to further improve the gain of the antenna element, the reflection plate technology is applied in the present application to further concentrate the antenna element radiation energy in space. The present application does not use a balun structure, which can reduce the height of the antenna element, can reduce the size of the reflection plate, and can reduce the production cost.

[0042] On the side of the PCB board 20 away from the bottom of the box 101, a metal circular-ring director 30 is also provided, and there is a certain distance between the circular-ring director 30 and the PCB board 20. The center of the metal circular-ring director 30 and the center of the PCB board 20 are located on the same vertical line. The circular-ring director 30 can further focus the energy emitted by the antenna to enhance the overall gain of the antenna. And while the circular director 30 enhances the antenna power, it also brings additional resonant frequencies to increase the operating bandwidth of the antenna.

[0043] As shown in combination with Figure 2 the figure, the PCB board 20 is fixed inside the reflection box 10. A copper layer is laid on one side of the PCB board 20 close to the reflector, and a first feeding circuit and a second feeding circuit are provided on the other side.

[0044] As shown in Figure 2 the figure, among them, there are four coupling slots in the copper layer, including the first slot 201, the second slot 202, the third slot 203, and the fourth slot 204. The first slot 201 and the second slot 202 are arranged on the same straight line, the third slot 203 and the fourth slot 204 are arranged on the same straight line, and the straight line where the first slot 201 and the second slot 202 are located is perpendicular to the straight line where the third slot 203 and the fourth slot 204 are located. The first slot 201, the second slot 202, the third slot 203, and the fourth slot 204 are orthogonal to each other in turn to generate orthogonal electric fields and form a ±45° dual-polarized antenna.

[0045] In an embodiment of the present invention, the shapes and structures of the four coupling slots are the same, and each slot is axisymmetric along a diagonal line of the PCB board 20. Taking the first slot 201 as an example, the first slot 201 includes a slot body, a slot head 2011 provided at one end of the slot body close to the center of the PCB board 20, and a slot tail 2012 provided at one end of the slot body away from the center of the PCB board 20. The slot head 2011 is arrow-shaped, and the slot tail 2012 coincides with a corner of the PCB board 20, which can achieve impedance matching and reduce the size of the antenna.

[0046] In the present invention, more co-frequency resonant structures are introduced. Any two coupling slots are not connected to each other and are independent of each other. The two slot lines on the same straight line represent the same polarization direction. The slots representing different polarizations are arranged orthogonally to each other, and the energy excited by them propagates into space. The fine microstrip line at the bottom is also arranged orthogonally to the slots to facilitate the transfer of electromagnetic energy to the slots.

[0047] In addition, the width of the slot is greater than the width of any microstrip line in the feeding circuit, and the distance between the 4 coupling slots is larger, which can further improve the isolation degree.

[0048] As shown in Figure 3As shown, specifically, the first feeding circuit includes a first thick microstrip line 206 and a first thin microstrip line 205, wherein the first thin microstrip line 205 includes a thin head section 2051, a thin middle section 2052 and a thin tail section 2053 connected in sequence. Wherein, in combination with Figures 3-4 As shown, the thin head section 2051 is perpendicular to the position of the first gap 201, the thin tail section 2053 is perpendicular to the position of the second gap 202, and the thin middle section 2052 is a multi-bending structure, one end of which is connected to the thin head section 2051 close to one end of the third gap 203, and the other end is connected to the thin tail section 2053 close to one end of the third gap 203. It should be noted that the thin middle section 2052 does not overlap or intersect with any one of the coupling gaps. The first thick microstrip line 206 includes a thick head section 2061, a thick middle section 2062 and a thick tail section 2063 connected in sequence, wherein one end of the thick head section 2061 is connected to the thin middle section 2052, and the other end is connected to the thick middle section 2062, one end of the thick tail section 2063 is connected to the thick middle section 2062, and the other end is located at the first cable joint 207.

[0049] Continuing to refer to Figures 3-4 As shown, the second feeding circuit includes a second thin microstrip line 208 and a second thick microstrip line 209, and the second thin microstrip line 208 is axially symmetrical to the first thin microstrip line 205 with the center axis between the first gap 201 and the third gap 203 as the axis of symmetry, and the intersection position of the first thin microstrip line 205 and the second thin microstrip line 208 is orthogonal. However, in order to avoid the intersection of the first feeding circuit and the second feeding circuit, and to ensure the consistency of the first feeding circuit and the second feeding circuit, a bridge is used at the intersection node of the first thin microstrip line 205 and the second thin microstrip line 208. The specific bridging method is: cutting the second thin microstrip line 208 at the node, connecting the cut-off part by a copper-clad PCB metalized via, and realizing conduction. Of course, the first thin microstrip line 205 can also be cut off at the node, which does not affect the implementation of the present application.

[0050] Similarly, with the center axis between the first gap 201 and the third gap 203 as the axis of symmetry, the thick head section and the thick middle section of the second thick microstrip line 209 are symmetrical to the thick head section 2061 and the thick middle section 2062 of the first thick microstrip line 206, and the thick tail section of the second thick microstrip line 209 is parallel to the thick tail section of the first microstrip line, and the second cable joint 210 is led out at the end of the thick tail section.

[0051] The ends of the first feeding circuit and the second feeding circuit are not provided with a bending, but are in a short-circuit form, which increases the amount of gap electromagnetic coupling compared with the open-circuit coupling form. And the first cable joint 207 and the second cable joint 210 feeding points of the dual-polarized two-port are close, which is very suitable for multi-vibrator array layout and is not easy to physically interfere with other interfaces.

[0052] According to relevant simulation tests, the simulation and actual measurement frequency bands in the application are 1.69-2.69 GHz, and the relative bandwidth reaches 40%.

[0053] In the application, only one layer of PCB is arranged, and the substrate material is diversified, which is sufficient to meet different cost control requirements in the market, and the structure is more simple, the volume is more optimized, and the material is more saved; the antenna in the application has a wider working bandwidth while realizing high gain and low profile, the polarization purity of a single polarized antenna is higher, the polarization isolation degree between different polarizations of the antenna is higher, and the antenna is suitable for direct feeding of various 50-ohm cables (such as 141, 120, 086, etc.).

[0054] Finally, it should be noted that: the above examples are only used to illustrate the technical solutions of the application, but not to limit it. Although the application has been described in detail with reference to the foregoing examples, those skilled in the art should understand that: it can still modify the technical solutions recorded in the foregoing examples, or make equivalent replacement for part or all of the technical features, and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the application.

Claims

1. An antenna with low profile dual polarized slot antenna elements, characterized by, The application relates to a reflection box and a PCB board fixed in the reflection box. The reflection box is a box without a cover, comprising a bottom and four side walls. The PCB board is fixed in the reflection box, and the distance between the PCB board and the bottom is at least 1 mm. The side of the PCB board away from the bottom is provided with a first feeding circuit and a second feeding circuit, and the first feeding circuit and the second feeding circuit are perpendicular to each other. The side of the PCB board close to the bottom is provided with a copper layer, and the copper layer is provided with two groups of coupling slots for radiating electromagnetic waves and perpendicular to each other. The coupling slots comprise a first slot, a second slot, a third slot and a fourth slot, the first slot and the second slot are arranged on the same straight line, the third slot and the fourth slot are arranged on the same straight line, and the straight line where the first slot and the second slot are arranged is perpendicular to the straight line where the third slot and the fourth slot are arranged. The first slot, the second slot, the third slot and the fourth slot are perpendicular to each other in sequence to generate perpendicular electric fields and form a dual-polarized antenna with an angle of +45 degrees. The first slot, the second slot, the third slot and the fourth slot are the same in structure, the first slot is axisymmetric along a diagonal line of the PCB board, the first slot comprises a slot body, a slot head arranged at one end of the slot body close to the center of the PCB board and a slot tail arranged at one end of the slot body away from the center of the PCB board, the slot head is arrow-shaped, and the slot tail coincides with a corner of the PCB board. The first feeding circuit comprises a first thick microstrip line and a first thin microstrip line, the first thin microstrip line is arranged on the PCB board, one end of the first thick microstrip line is connected with the first thin microstrip line, and the other end of the first thick microstrip line is led out as a first cable joint.

2. The antenna with low-profile dual-polarized slot antenna elements according to claim 1, characterized in that: The first thin microstrip line comprises a thin head section, a thin middle section and a thin tail section connected in sequence, the thin head section is perpendicular to the position of the first slot, the thin tail section is perpendicular to the position of the second slot, the thin middle section is a multi-bending structure to avoid any coupling slot, one end of the thin middle section is connected with one end of the thin head section close to the third slot, and the other end of the thin middle section is connected with one end of the thin tail section close to the third slot.

3. The antenna with low-profile dual-polarized slot antenna elements of claim 2, wherein: The first thick microstrip line comprises a thick head section, a thick middle section and a thick tail section connected in sequence, one end of the thick head section is connected with the thin middle section, the other end of the thick head section is connected with the thick middle section, one end of the thick tail section is connected with the thick middle section, and the other end of the thick tail section is led out as the first cable joint.

4. The antenna with low-profile dual-polarized slot antenna elements of claim 3, wherein: The second feeding circuit comprises a second thin microstrip line and a second thick microstrip line, the second thin microstrip line is axisymmetric with the first thin microstrip line with the central axis between the first slot and the third slot as the axis of symmetry, and the intersection of the first thin microstrip line and the second thin microstrip line is perpendicular.

5. The antenna with low-profile dual-polarized slot antenna elements of claim 2, wherein: The first thin microstrip line or / and the second thin microstrip line is bridged at the intersection node.

6. The antenna with low-profile dual-polarized slot antenna elements of claim 5, wherein: ​ 7. The antenna with low-profile dual-polarized slot antenna elements of claim 5, wherein: With the central axis between the first gap and the third gap as the axis of symmetry, the thick head section and the thick middle section of the second thick microstrip line are axially symmetrical to the thick head section and the thick middle section of the first thick microstrip line, the thick tail section of the second thick microstrip line is parallel to the thick tail section of the first thick microstrip line, one end of the thick tail section of the second thick microstrip line is connected to the thick middle section of the second thick microstrip line, and the other end is led out as a second cable connector.

8. The antenna with low-profile dual-polarized slot antenna elements of claim 1, wherein: Further comprising a metal circular loop director arranged on one side close to the first feeding circuit and the second feeding circuit on the PCB board, and the distance between the circular loop director and the PCB board is at least 1mm.

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