Differential feeding network and antenna

Abstract

The present disclosure provides a differential feeding network and an antenna for a dual-polarized antenna. The differential feeding network includes a first feeder and a second feeder that intersect each other, and the first feeder and the second feeder intersect at a center point. The first feeder includes a first feed output port and a second feed output port respectively disposed at two ends of the first feeder, and the second feeder includes a third feed output port and a fourth feed output port respectively disposed at two ends of the second feeder. The differential feeding network further includes a first input feeder and a second input feeder. One end of the first input feeder is provided with a first feed input port, and the other end of the first input feeder is electrically connected to the first feeder. One end of the second input feeder is provided with a second feed input port, and the other end of the second input feeder is electrically connected to the second feeder. The first feeder and the second feeder are electrically connected to each other at the center point.

Description

Technical Field

[0001] The present disclosure relates to the field of communication technologies, and particularly to a differential feeding network and an antenna. Background Art

[0002] With the rapid development of mobile communication technologies, the operating frequency of base station antennas has been continuously increasing, and the degree of integration has been gradually rising. Therefore, it is required that the antenna simultaneously has the requirements of high radiation efficiency, low cross polarization, and symmetric radiation pattern. In addition, due to the gradual depletion of the spatial resources for setting up antennas, compact small-spacing antenna arrays and multi-frequency common-aperture antenna arrays can obtain stronger signal transmission capabilities within a limited antenna aperture, and thus have received wide attention. However, these application environments pose higher requirements on the miniaturization degree of antenna elements and feeding networks.

[0003] Therefore, providing a compact differential feeding network is the key to realizing high-performance base station antennas. Summary of the Invention

[0004] The present disclosure provides a differential feeding network and an antenna.

[0005] In a first aspect, an embodiment of the present disclosure provides a differential feeding network for a dual-polarized antenna, including: a first feeder and a second feeder that intersect with each other, wherein the first feeder and the second feeder intersect at a center point, the first feeder includes a first feeding output port and a second feeding output port respectively disposed at two end points of the first feeder, the second feeder includes a third feeding output port and a fourth feeding output port respectively disposed at two end points of the second feeder, the differential feeding network further includes a first input feeder and a second input feeder, one end of the first input feeder is provided with a first feeding input port, the other end of the first input feeder is electrically connected to the first feeder, one end of the second input feeder is provided with a second feeding input port, the other end of the second input feeder is electrically connected to the second feeder, wherein the first feeder and the second feeder are electrically connected to each other at the center point.

[0006] In a second aspect, an embodiment of the present disclosure provides a matrix-type differential feeding network, including a plurality of unit differential feeding networks arranged in a matrix, the unit differential feeding network including a differential feeding network according to an embodiment of the present disclosure, wherein the first input feeders of at least two unit differential feeding networks located in the same column are electrically connected to each other and the second input feeders are electrically connected to each other, and the at least two unit differential feeding networks are fed via the same first feeding input port and the same second feeding input port.

[0007] In a third aspect, embodiments of the present disclosure provide an antenna, which includes a metal radiation patch, a differential feeding network, and a metal reflector. The differential feeding network includes a differential feeding network according to embodiments of the present disclosure. The metal radiation patch is disposed above the differential feeding network, and the differential feeding network is disposed above the metal reflector. The antenna further includes a connection structure disposed between the metal radiation patch and the differential feeding network.

[0008] The differential feeding network according to embodiments of the present disclosure is a miniaturized differential feeding network. By setting the first feeder and the second feeder to be electrically connected to each other at the center point, the wiring area of the differential feeding network can be reduced, and the differential feeding network can have a symmetric structure to avoid the problem of asymmetry in the antenna radiation pattern. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] In the drawings of embodiments of the present disclosure:

[0010] Figure 1 Examples of dual-polarized antennas and differential feeding networks in the related art are shown;

[0011] Figure 2 A top view of a differential feeding network for a dual-polarized antenna according to embodiments of the present disclosure is shown;

[0012] Figure 3 A current schematic diagram when the differential feeding network according to embodiments of the present disclosure excites the antenna is shown;

[0013] Figure 4 An equivalent circuit diagram of an antenna using the differential feeding network according to embodiments of the present disclosure is shown;

[0014] Figure 5 Circuit simulation results of an antenna using the differential feeding network according to embodiments of the present disclosure are shown;

[0015] Figure 6 Another top view of the differential feeding network according to embodiments of the present disclosure is shown;

[0016] Figure 7 Another top view of the differential feeding network according to embodiments of the present disclosure is shown;

[0017] Figure 8 Another top view of the differential feeding network according to embodiments of the present disclosure is shown;

[0018] Figure 9 A schematic structural diagram of the antenna according to embodiments of the present disclosure is shown;

[0019] Figure 10 Shows Figure 9 The connection structure in the shown antenna;

[0020] Figure 11 shows Figure 9 the surface electric field distribution of the differential feeding network of the antenna shown;

[0021] Figure 12 shows Figure 9 the S-parameter diagram of the antenna shown;

[0022] Figure 13 shows Figure 9 the radiation pattern of the antenna shown;

[0023] Figure 14 shows another example of a differential feeding network according to an embodiment of the present disclosure;

[0024] Figure 15 shows a schematic structural diagram of an antenna according to an embodiment of the present disclosure;

[0025] Figure 16 shows Figure 15 the surface electric field distribution of the metal radiation patch and the differential feeding network of the antenna shown;

[0026] Figure 17 shows Figure 15 the S-parameter diagram of the antenna shown;

[0027] Figure 18 shows Figure 15 the radiation pattern of the antenna shown;

[0028] Figure 19 shows various deformation examples of an antenna according to an embodiment of the present disclosure;

[0029] Figure 20 shows a deformation example of an antenna according to an embodiment of the present disclosure;

[0030] Figure 21 shows an example of a matrix-type differential feeding network according to an embodiment of the present disclosure. Detailed implementation manners

[0031] To enable those skilled in the art to better understand the technical solutions of the present disclosure, the embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings.

[0032] In the following, the present disclosure will be described more fully with reference to the accompanying drawings, but the disclosed embodiments may be embodied in different forms and the present disclosure should not be construed as limited to the embodiments set forth below. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the present disclosure to those skilled in the art.

[0033] The accompanying drawings of the embodiments of the present disclosure are used to provide a further understanding of the embodiments of the present disclosure, and constitute a part of the specification. Together with the detailed embodiments, they are used to explain the present disclosure and do not constitute a limitation to the present disclosure. By describing the detailed embodiments with reference to the accompanying drawings, the above and other features and advantages will become more apparent to those skilled in the art.

[0034] The present disclosure can be described with reference to plan views and / or cross-sectional views by means of ideal schematic diagrams of the present disclosure. Therefore, the example illustrations can be modified according to manufacturing techniques and / or tolerances.

[0035] In the case of no conflict, the embodiments of the present disclosure and the features in the embodiments can be combined with each other.

[0036] The terms used in the present disclosure are only for describing specific embodiments and are not intended to limit the present disclosure. As used in the present disclosure, the term "and / or" includes any and all combinations of one or more of the related listed items. As used in the present disclosure, the singular forms "a" and "the" are also intended to include the plural forms unless the context clearly indicates otherwise. As used in the present disclosure, the terms "comprising", "made of...", specify the presence of the described features, wholes, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, wholes, steps, operations, elements, components and / or their groups.

[0037] Unless otherwise defined, the meanings of all terms (including technical and scientific terms) used in the present disclosure are the same as those commonly understood by those of ordinary skill in the art. It will also be understood that terms such as those defined in common dictionaries should be interpreted as having a meaning consistent with their meaning in the relevant art and the context of the present disclosure, and will not be interpreted as having an idealized or overly formal meaning unless the present disclosure clearly so defines.

[0038] The present disclosure is not limited to the embodiments shown in the accompanying drawings, but includes modifications to the configurations formed based on manufacturing processes. Therefore, the regions illustrated in the accompanying drawings have schematic attributes, and the shapes of the regions shown in the figures illustrate the specific shapes of the regions, but are not intended to be restrictive.

[0039] Common forms of base station antenna units include microstrip antennas and dipole antennas. In order to ensure the working bandwidth, the antenna usually needs to have a certain profile height, but this will cause the antenna pattern to shift and the cross-polarization to deteriorate. In some designs, slits are opened or parasitic mechanisms are loaded at specific positions of the antenna to suppress cross-polarization, but this will make the structure of the antenna become complex.

[0040] To solve these problems, differential feeding has become the mainstream design solution in current base station antenna design. In related technologies, to avoid the overlapping short circuit of the two polarization lines of the differential feeding network, a large wiring area is required, which cannot adapt to the miniaturization trend of array antennas. In addition, for microstrip antennas with a relatively low profile height, the asymmetric wiring form of the differential feeding network in related technologies is prone to generate asymmetric coupling with the radiation structure, resulting in an asymmetric antenna pattern and deteriorating performance such as standing wave and gain.

[0041] Figure 1 An example of a dual-polarized antenna and a differential feeding network in related technologies is shown. Figure 1 The left side of shows a perspective view of a dual-polarized antenna including a metal radiation patch and a differential feeding network, Figure 1 and the right side of shows a top view of the differential feeding network.

[0042] As Figure 1 shown, to achieve a symmetric pattern and low cross-polarization, a dual-polarized antenna usually uses a differential feeding structure. The antenna has four feed output ports, and each polarization is excited by two feed output ports with equal amplitudes and a phase difference of 180 degrees respectively. To interconnect with the feeding network of the antenna array, a differential feeding network composed of two 1-to-2 power dividers is required to reduce the number of feed input ports for each polarization to one.

[0043] As Figure 1 shown, ports P1 and P2 of the differential feeding network are the feed input ports for the two polarizations of the dual-polarized antenna respectively, and the differential feeding network feeds the metal radiation patch via four feed output ports P3, P4, P5, and P6. Feed output ports P3 and P6 form a differential pair, and feed output ports P4 and P5 form a differential pair. When port P1 is fed, currents flow along paths a and b (shown as dashed lines in the figure) to feed output ports P3 and P6 respectively. The phase difference between feed output ports P3 and P6 is determined by the length difference between paths a and b. To ensure a symmetric pattern, the phase difference is usually set to 180 degrees. Similarly, when port P2 is fed, feed output ports P4 and P5 are excited, with equal amplitudes and a phase difference of 180 degrees. By using a differential feeding network, a high isolation state can be maintained between port P1 and port P2.

[0044] By Figure 1As can be seen from the example, in the differential feeding network of the related art, in order to ensure the isolation between the feeding input ports P1 and P2 for the two polarizations, a separate 1-to-2 power splitter is used for each polarization. At the same time, in order to reduce the coupling between the transmission lines, a certain distance needs to be maintained between the two power splitters. The above settings will cause the entire differential feeding network to occupy a large wiring area, which not only restricts the miniaturization of the antenna array, but also causes additional insertion loss, thereby reducing the antenna efficiency. On the other hand, Figure 1 The differential feed network shown in the figure also causes an asymmetric problem in the antenna radiation pattern due to its own asymmetric structure.

[0045] The embodiments of the present disclosure provide a compact differential feeding network.

[0046] Figure 2 A top view of a differential feeding network for a dual-polarized antenna according to an embodiment of the present disclosure is shown.

[0047] like Figure 2 As shown, the differential feeding network for a dual-polarized antenna according to an embodiment of the present disclosure includes a first feed line FL1 and a second feed line FL2 intersecting each other, and the first feed line FL1 and the second feed line FL2 intersect at a center point O. The first feed line FL1 includes a first feed output port P3 and a second feed output port P6 respectively provided at two end points of the first feed line FL1, and the second feed line FL2 includes a third feed output port P4 and a fourth feed output port P5 respectively provided at two end points of the second feed line FL2. Figure 1 As shown, the differential feed network for a dual-polarized antenna according to an embodiment of the present disclosure further includes a first input feeder IFL1 and a second input feeder IFL2. A first feed input port P1 is provided at one end of the first input feeder IFL1, and the other end of the first input feeder IFL1 is electrically connected to the first feeder FL1. A second feed input port P2 is provided at one end of the second input feeder IFL2, and the other end of the second input feeder IFL2 is electrically connected to the second feeder FL2. The first feeder FL1 and the second feeder FL2 are electrically connected to each other at a center point O.

[0048] The differential feeding network according to the embodiment of the present disclosure may be integrally formed of a metal material.

[0049] Figure 3 A schematic diagram of current flow when a differential feeding network excites an antenna according to an embodiment of the present disclosure is shown.

[0050] like Figure 3As shown, when the first feed input port P1 is fed, current (shown as a dashed line in the figure) flows through the first feed output port P3 and the second feed output port P6. The phase difference between the first feed output port P3 and the second feed output port P6 is determined by the line length L from the center point O to each feed output port f and the line width W f can control the power ratio of the two feed output ports. When using the differential feed network according to the embodiments of the present disclosure to excite the antenna element, each feed output port P3, P4, P5, and P6 is connected to four corresponding feed positions of the antenna, and the impedance from each feed output port to the antenna is the same and matches the impedance of the antenna.

[0051] The technical principle of the present disclosure will be described below.

[0052] First, an explanation will be given for why a high isolation can be maintained between the feed input ports P1 and P2 when the first feeder FL1 intersects and is electrically connected to the second feeder FL2.

[0053] When the feed input port P1 is excited, the antenna mode corresponding to its polarization is excited (for example, the +45-degree polarization mode), and the direction of the current is as Figure 3 shown. The dashed line represents the current path when the feed input port P1 is excited, and the arrow represents the direction of the current. By selecting an appropriate line length L f such that the phase difference θ lf between the center point O and each feed output port is 90°, the phase difference between the first feed output port P3 and the second feed output port P6 is 180°. In this case, the +45-degree polarization mode of the antenna is excited, and the -45-degree polarization mode of the antenna, as an orthogonal mode, is related to the excitation of the feed input port P2.

[0054] The impedance Z 4a from the third feed output port P4 and the fourth feed output port P5 to the antenna 5a and Z

[0055] are infinite, that is: 4a Z 5a = Z 34 = ∞

[0056] The impedance Z 35 from the first feed output port P3 to the third feed output port P4 and the fourth feed output port P5 can be calculated by the following formula:

[0057]

[0058] where Z0 is the characteristic impedance of the feeder.

[0059] Therefore, the current at the feeding input port P1 flows along the path shown in the figure (i.e., the line of the first feeder FL1), exciting the +45-degree polarization mode of the antenna, and does not flow along the center point O to the orthogonal line (i.e., the line of the second feeder FL2). Therefore, it does not affect the isolation between the antenna feeding input ports P1 and P2, nor does it affect the cross-polarization performance of the radiation pattern.

[0060] Secondly, an explanation is given for why a short-circuit point to the ground can be set at the center point O.

[0061] The impedance Z from the center point O to the third feeding output port P4 and the fourth feeding output port P5 O4 and Z O5 can be calculated by the following formula:

[0062]

[0063] Therefore, relative to the +45-degree polarization, the orthogonal -45-degree polarization can be equivalent to a short-circuit structure at the center point O. Therefore, a short-circuit point to the ground can be set at the center point O without affecting the performance of the antenna.

[0064] Compared with the differential feeding network of the related technology, the differential feeding network according to the embodiments of the present disclosure can effectively reduce the line length of the feeding network, and thus can reduce the loss of the feeding network. When the differential feeding network according to the embodiments of the present disclosure is applied in an antenna array with a small pitch, it can have the advantages of symmetry and miniaturization. The symmetric feeding structure can generate symmetric near-field coupling with the antenna radiation structure, and thus does not affect the symmetry of the antenna radiation pattern. In addition, the miniaturized differential feeding network can reserve a larger area for the feeding network of the sub-array, avoiding line crosstalk caused by too small line spacing, and further avoiding affecting the transmission performance. The differential feeding network according to the embodiments of the present disclosure can be used as the differential feeding network of a dual-polarized antenna, and can solve the problems of performance deterioration of the differential feeding antenna and the large wiring area of the differential feeding network.

[0065] Figure 4 Shows an equivalent circuit diagram of an antenna using the differential feeding network according to the embodiments of the present disclosure.

[0066] As Figure 4 shown, each feeding output port is connected to the metal radiation patch of the antenna, which can be equivalent to a parallel RLC (PRLC) load. The coupling between each feeding output port can be equivalent to a parallel LC circuit. TL1 to TL4 are differential feeding networks connected in the center. The feeding input ports P1 and P2 feed the antenna elements through the transmission lines TL5 and TL6 respectively, and respectively correspond to two different polarization modes. The reflection coefficient and isolation of the antenna can be adjusted according to actual requirements.Figure 5 The circuit simulation results of an antenna using a differential feeding network according to an embodiment of the present disclosure are shown. Among them, the S(1, 1) curve shows the variation of the reflection coefficient with frequency, and the S(1, 2) curve shows the variation of the isolation with frequency. As Figure 5 shown, the antenna resonates at 4.9 GHz, and the isolation of the ports is greater than 33 dB.

[0067] Figures 6 to 8 Various deformation examples of the differential feeding network according to an embodiment of the present disclosure are shown.

[0068] As Figure 6 shown, in a deformation example of the differential feeding network according to an embodiment of the present disclosure, the first feeder FL1 may include a first bent portion and a second bent portion, and the second feeder FL2 may include a third bent portion and a fourth bent portion. The first bent portion is disposed between the first feed output port P3 and the center point O, the second bent portion is disposed between the second feed output port P6 and the center point O, the third bent portion is disposed between the third feed output port P4 and the center point O, and the fourth bent portion is disposed between the fourth feed output port P5 and the center point O. The first bent portion to the fourth bent portion have the same wiring pattern and are arranged to be rotationally symmetric about the center point O. By providing bent portions on the first feeder FL1 and the second feeder FL2, further miniaturization can be achieved.

[0069] As Figure 7 shown, in a deformation example of the differential feeding network according to an embodiment of the present disclosure, the first feeder FL1 may include a first portion between the first feed output port P3 and the center point O and a second portion between the second feed output port P6 and the center point O, and the first portion includes a fifth bent portion. The second feeder FL2 may include a third portion between the third feed output port P4 and the center point O and a fourth portion between the fourth feed output port P5 and the center point O, and the third portion includes a sixth bent portion. The first portion of the first feeder FL1 and the fourth portion of the second feeder FL2 form a first pattern, the third portion of the second feeder FL2 and the second portion of the first feeder FL1 form a second pattern, and the first pattern and the second pattern are symmetric with each other.

[0070] As Figure 8As shown, in a variant example of the differential feeding network according to an embodiment of the present disclosure, the first feeder FL1 may include a first portion between the first feed output port P3 and the center point O, and a second portion between the second feed output port P6 and the center point O, and the first portion and the second portion are not on the same straight line. The second feeder FL2 may include a third portion between the third feed output port P4 and the center point O, and a fourth portion between the fourth feed output port P5 and the center point O, and the third portion and the fourth portion are not on the same straight line. The first portion of the first feeder FL1 and the fourth portion of the second feeder FL2 form a third pattern, the third portion of the second feeder FL2 and the second portion of the first feeder FL1 form a fourth pattern, and the third pattern and the fourth pattern are symmetric to each other.

[0071] According to an embodiment of the present disclosure, as Figure 2 and Figure 6 shown, the first input feeder IFL1 is electrically connected to the first feed output port P3 of the first feeder FL1, and the second input feeder IFL2 is electrically connected to the third feed output port P4 of the second feeder FL2.

[0072] According to an embodiment of the present disclosure, as Figure 7 and Figure 8 shown, the connection point of the first input feeder IFL1 and the first feeder FL1 is between the first feed output port P3 and the center point O, and the connection point of the second input feeder IFL2 and the second feeder FL2 is between the third feed output port P4 and the center point O.

[0073] It should be recognized that, as needed, the differential feeding network can be formed into various other forms. For example, vias can be formed on the feeder, the line width and thickness of the trace can be changed, etc. As long as there is a connection between the feeding lines for the two polarizations of the antenna, it is within the protection scope of the present application. The present application aims to protect all possible variant embodiments.

[0074] In addition, although in the previous embodiments, the phase difference between the feeding input port of the same polarization to the two feed output ports is expressed as 180°, for example, the phase difference between the first feed output port P3 and the second feed output port P6 is expressed as 180°, those skilled in the art should understand that the phase difference between the feeding input port of the same polarization to the two feed output ports can be an integral multiple of 180 degrees. For example,

[0075] θ 16 -θ 13 =n×180°, n = 1, 2, 3…

[0076] θ 25 -θ 24 =n×180°, n = 1, 2, 3…

[0077] Among them, θ 16 represents the phase difference between the first feed input port P1 and the second feed output port P6, and θ 13 represents the phase difference between the first feed input port P1 and the first feed output port P3, and θ 25 represents the phase difference between the second feed input port P2 and the fourth feed output port P5, and θ 24 represents the phase difference between the second feed input port P2 and the third feed output port P4.

[0078] Next, taking the example of the differential feed network shown in Figure 6 as an example, the antenna according to the embodiments of the present disclosure will be described.

[0079] Figure 9 shows a schematic structural diagram of the antenna according to the embodiments of the present disclosure. Figure 9 The left side of shows a top view of the antenna, Figure 9 and the right side of shows a perspective view of the antenna.

[0080] As shown in Figure 9 , the antenna according to the embodiments of the present disclosure includes a metal radiation patch 901, a differential feed network 902, a metal reflector 903, and a connection structure 904 disposed between the metal radiation patch and the differential feed network. In the example of Figure 9 , the differential feed network 902 is the example of the differential feed network shown in Figure 6 . The metal radiation patch 901 is placed above the differential feed network 902, and the differential feed network 902 is placed above the metal reflector 903. Figure 9 The antenna shown in can be an integrated pure metal structure and can work properly without an additional fixing structure.

[0081] According to the embodiments of the present disclosure, as shown in Figure 9 and Figure 10 , the connection structure 904 may include four metal posts respectively electrically connected to the first feed output port P3 to the fourth feed output port P5. One end of each metal post is electrically connected to one of the first feed output port P3 to the fourth feed output port P5, and the other end of each metal post is electrically connected to the corresponding feed position in the metal radiation patch 901.

[0082] For Figure 9When designing the antenna shown, the radiation structure and the feeding structure can be designed separately. The size of the metal radiation patch 901 can be selected according to the appropriate frequency band, and the metal radiation patch 901 is fed through four rotationally symmetric vertical metal posts (i.e., the connection structure 904), and four feeding ports are provided below the metal posts. The antenna can be adjusted to a matching state by optimizing the positions of the metal posts. When designing the differential feeding network 902, the equivalent circuit diagram can be referred to, and the impedances and positions of the feeding output ports (i.e., the first feeding output port P3 to the fourth feeding output port P5) of the differential feeding network 902 are the same as those of the four feeding ports below the metal posts. By adjusting the line length L f and the line width W f of the cross structure located at the center, the power ratio of the feeding output ports of the same polarization is adjusted to 1:1, and the phase is 180 degrees. By combining the designed radiation structure (i.e., the metal radiation patch 901) and the feeding structure (i.e., the differential feeding network 902) according to the positions of the feeding output ports, the designed antenna can be obtained.

[0083] Figure 11 shows Figure 9 the surface electric field distribution of the differential feeding network of the antenna shown.

[0084] As Figure 11 shown, when a single feeding input port is fed, the power is transmitted to the two feeding output ports corresponding to the polarization, and the electric field on the path of the other polarization is very small, which is equivalent to an open state. Among them, the lighter the color, the larger the electric field value, and the darker the color, the smaller the electric field value. It can be seen that Figure 11 the surface electric field distribution of the differential feeding network shown is consistent with the technical principle description provided before.

[0085] Figure 12 shows Figure 9 the S-parameter diagram of the antenna shown, Figure 13 shows Figure 9 the radiation pattern of the antenna shown. Figure 13 The left side of Figure 13 shows the radiation pattern when phi = 0 degrees, and the right side of

[0086] shows the radiation pattern when phi = 90 degrees. Figure 12 As Figure 9 shown, the return loss of the antenna shown at 4.876 GHz is less than -37 dB (see curves S(1, 1) and S(2, 2)), and the isolation is greater than 24 dB (see curve S(2, 1)). As Figure 13 shown, Figure 9The radiation patterns of the two main radiation planes of the antenna shown at phi = 0 degrees and phi = 90 degrees are symmetric (see the curves in the middle of the figure). The antenna gain is 9.5 dB, and the cross-polarization level is low (see the curves in the lower part of the figure), with good radiation characteristics.

[0087] Figure 14 Another example of a differential feeding network according to an embodiment of the present disclosure is shown.

[0088] As Figure 14 shown, the differential feeding network according to an embodiment of the present disclosure may further include four L-shaped feeding coupling components respectively electrically connected to the first feeding output port to the fourth feeding output port. Each L-shaped feeding coupling component includes a vertical portion and a horizontal portion. One end of the vertical portion is connected to one end of the horizontal portion, and the other end of the vertical portion is connected to one of the first feeding output port to the fourth feeding output port. The horizontal portion extends in the direction towards the center point, and the extension length of the horizontal portion is less than the distance between one of the first feeding output port to the fourth feeding output port and the center point.

[0089] It should be recognized that Figure 14 the cylindrical object shown at the center point is a connection structure for connecting the differential feeding network to the metal radiation patch above it, and should not be understood as a part of the differential feeding network.

[0090] According to an embodiment of the present disclosure, the vertical portion may have a cylindrical shape, and the horizontal portion may have one of the shapes of a rectangle, a circle, an ellipse, or a sector. It should be recognized that, according to needs, the vertical portion and the horizontal portion may have various shapes, as long as the horizontal portion has a certain projected area relative to the radiation patch, that is, it can provide appropriate coupling, so as to feed the radiation patch, and all are within the protection scope of the present application. The present application aims to protect all possible deformed implementation manners.

[0091] Next, taking Figure 14 the example of the differential feeding network shown as an example, the antenna according to an embodiment of the present disclosure will be described.

[0092] Figure 15 A schematic structural diagram of an antenna according to an embodiment of the present disclosure is shown. Figure 15 The top view of the antenna is shown on the left side of Figure 15 and the exploded perspective view of the antenna is shown on the right side of

[0093] As Figure 15 shown, the antenna according to an embodiment of the present disclosure includes a metal radiation patch 1501, a differential feeding network 1502, a metal reflector 1503, and a connection structure 1504 provided between the metal radiation patch and the differential feeding network. In Figure 15 the example ofFigure 14 An example of the differential feeding network shown. The metal radiation patch 1501 is placed above the differential feeding network 1502, and the differential feeding network 1502 is placed above the metal reflector 1503. The four feeding output ports of the differential feeding network 1502 are respectively connected to four L-shaped feeding coupling components to excite the upper metal radiation patch 1501 in a coupled manner. Each L-shaped feeding coupling component includes a vertical portion and a horizontal portion. One end of the vertical portion is connected to one end of the horizontal portion, and the other end of the vertical portion is connected to one of the first to fourth feeding output ports. The horizontal portion extends in the direction towards the center point, and the extending length of the horizontal portion is less than the distance between one of the first to fourth feeding output ports and the center point. The cross structure in the middle of the differential feeding network 1502 is connected to the center point of the metal radiation patch 1501 through a metal column (i.e., the connection structure 1504). Figure 15 The antenna shown can be an integrated pure metal structure.

[0094] According to an embodiment of the present disclosure, as Figure 15 shown, the connection structure 1504 may include a central connection column connecting the center point of the differential feeding network 1502 and the center point of the metal radiation patch 1501. The height of the central connection column is greater than the height of the vertical portion of the L-shaped feeding coupling component.

[0095] Figure 16 shows Figure 15 the surface electric field distribution of the metal radiation patch and the differential feeding network of the antenna shown. Figure 16 The left side of Figure 16 shows the surface electric field distribution of the metal radiation patch, and

[0096] as Figure 16 shown, when a single feeding input port feeds power, the power is transmitted to the two feeding output ports corresponding to the polarization and, while the electric field on the path of the other polarization is very small, equivalent to an open state, where the lighter the color, the greater the electric field value, and the darker the color, the smaller the electric field value. It can be seen that Figure 16 the surface electric field distribution of the differential feeding network shown is consistent with the technical principle description provided before. On the other hand, the electric field intensity at the center position of the metal radiation patch is the smallest, equivalent to an open state. Since the electric field intensities at the center positions of the metal radiation patch and the differential feeding network are both very small, a metal central connection column for support is provided between the two to connect the metal radiation patch and the differential feeding network, and no new current distribution will be introduced, and the antenna can maintain the original working mode.

[0097] Figure 17 shows Figure 15 the S-parameter diagram of the antenna shownFigure 18 shows Figure 15 the radiation pattern of the antenna shown Figure 18 The left side of Figure 18 shows the radiation pattern at phi = 0 degrees, and the right side of

[0098] As Figure 17 shown Figure 15 For the antenna shown, the return loss at 4.89 GHz is less than -21 dB (see curves S(1, 1) and S(2, 2)), and the isolation is greater than 32 dB (see curve S(2, 1)). As Figure 18 shown Figure 15 For the antenna shown, the patterns of the two main radiation planes at phi = 0 degrees and phi = 90 degrees are symmetric (see the curves in the middle of the figure), the antenna gain is 8.8 dB, and the cross-polarization level is low (see the curves in the lower part of the figure), having good radiation characteristics and can be used as a base station antenna unit.

[0099] According to an embodiment of the present disclosure, a grounded short-circuit point can be set at the center point of the differential feeding network.

[0100] It can be known through the equivalent circuit analysis of the antenna that a grounded short-circuit point can be set at the center point O of the differential feeding network. In an actual antenna array, the asymmetric coupling between the radiation structure and the feeding structure of the antenna cannot be completely avoided. Although this asymmetry has little influence on the antenna pattern, it will still cause the currents on the differential feeding network not to be absolutely symmetric. Setting a grounded short-circuit point at the center point O can ensure that the amplitude and phase difference of each polarization differential port are closer to the ideal state, ensuring that the pattern is more symmetric.

[0101] Figure 19 shows various deformation examples of the antenna according to an embodiment of the present disclosure.

[0102] As Figure 19 shown, according to an embodiment of the present disclosure, the vertical part of the L-shaped feeding coupling component of the differential feeding network is formed to be connected to the feeding line and the horizontal part of the L-shaped feeding coupling component by means of a rounded corner.

[0103] According to an embodiment of the present disclosure, the metal radiation patch can have one of a square, a rectangle, or a circle, or any other suitable shape. The metal radiation patch can also have at least one of the following structures: a groove, a bend, or a droop. The metal radiation patch can have a stacked structure of multiple patches.

[0104] According to an embodiment of the present disclosure, the central connection post is formed of a metallic material or a non-metallic material. That is, a pure metal antenna structure can use a support member of a non-metallic material or be attached to a structure of a non-metallic material. For example, around a structure with a relatively small surface electric field distribution of the antenna, a structure of a non-metallic material can be used to replace the structure of a metallic material for support. When applied to a dual-band antenna array, it can avoid common-mode interference to the lower-frequency antenna elements, and at the same time can adapt to a variety of processing technologies and still maintain a high radiation efficiency. Figure 19 It shows that a non-metallic central connection post or other non-metallic structural members that can play a supporting and / or positioning role are provided below the central position of the metal radiation patch.

[0105] The antenna according to an embodiment of the present disclosure can be formed into an integrated pure metal antenna, having low cross-polarization and a symmetric radiation pattern, and having higher efficiency. Without the need for an additional non-metallic support structure, the antenna according to an embodiment of the present disclosure is easy to assemble and has better environmental friendliness.

[0106] In the antenna according to an embodiment of the present disclosure, a structure of a non-metallic material can be used to replace the structure of a metallic material for support, and the non-metallic part is arranged at the position where the electric field distribution is the smallest. Therefore, it can also have the advantages of low loss and high efficiency, and there is no common-mode interference, and it can be applied to a compact dual-band array antenna.

[0107] Figure 20 It shows a deformation example of the antenna according to an embodiment of the present disclosure.

[0108] As Figure 20 shown, a traditional printed circuit board (PCB) process or a plastic module and other solutions can be used to fabricate the antenna, wherein the metallic material is attached to the non-metallic dielectric material. In this way, a symmetric pattern and low cross-polarization can still be achieved. However, due to the use of a non-metallic dielectric material in the electric field intensive area, the radiation efficiency of the antenna will be lost to some extent.

[0109] Figure 21 It shows an example of a matrix differential feeding network according to an embodiment of the present disclosure.

[0110] As Figure 21 shown, the present disclosure also provides a matrix differential feeding network, including a plurality of unit differential feeding networks arranged in a matrix, and the unit differential feeding network includes a differential feeding network according to various embodiments of the present disclosure. Among them, the first input feed lines of at least two unit differential feeding networks in the same column are electrically connected to each other and the second input feed lines are electrically connected to each other, and the at least two unit differential feeding networks are fed through the same first feeding input port and the same second feeding input port.

[0111] In Figure 21 In the example of the matrix differential feeding network shown, a small-spacing array of 4×8 scale with a horizontal spacing of 0.35 times the wavelength is shown. It can be seen that the differential feeding network has a very small wiring size, and thus can effectively relieve the pressure on the line layout of the differential feeding network of the compact array antenna.

[0112] It should be recognized that although in Figure 21 it is shown that the first input feed lines of the differential feeding networks of the respective units in the same column are electrically connected to each other and the second input feed lines are electrically connected to each other, the present disclosure is not limited thereto. According to the specific implementation process, the differential feeding networks of the respective units in the same column can be divided into multiple sub-arrays, and the differential feeding networks of the units are connected to each other within the same sub-array, and there is not necessarily a connection between the respective sub-arrays.

[0113] The present disclosure has disclosed example embodiments, and although specific terms are used, they are used only and should be construed only as having a general illustrative meaning and not for a limiting purpose. In some instances, it will be apparent to those skilled in the art that, unless otherwise expressly stated, the features, characteristics, and / or elements described in connection with a particular embodiment may be used alone or in combination with the features, characteristics, and / or elements described in connection with other embodiments. Accordingly, those skilled in the art will understand that various forms and details changes can be made without departing from the scope of the present disclosure as set forth by the appended claims.

Claims

1. A differential feeding network for a dual-polarized antenna, comprising: A first feeder and a second feeder that intersect each other, wherein the first feeder and the second feeder intersect at a center point. The first feeder includes a first feeding output port and a second feeding output port respectively provided at two ends of the first feeder. The second feeder includes a third feeding output port and a fourth feeding output port respectively provided at two ends of the second feeder. The differential feeding network further includes a first input feeder and a second input feeder. One end of the first input feeder is provided with a first feeding input port, and the other end of the first input feeder is electrically connected to the first feeder. One end of the second input feeder is provided with a second feeding input port, and the other end of the second input feeder is electrically connected to the second feeder. Wherein, the first feeder and the second feeder are electrically connected to each other at the center point. Wherein, the first input feeder is electrically connected to the first feeding output port of the first feeder, the second input feeder is electrically connected to the third feeding output port of the second feeder, or Wherein, the connection point of the first input feeder and the first feeder is located between the first feeding output port and the center point, and the connection point of the second input feeder and the second feeder is located between the third feeding output port and the center point.

2. The differential feeding network according to claim 1, wherein The first feeder and the second feeder are integrally formed.

3. The differential feeding network according to claim 1, wherein The first feeder includes a first bending portion and a second bending portion, and the second feeder includes a third bending portion and a fourth bending portion. The first bending portion is provided between the first feeding output port and the center point. The second bending portion is provided between the second feeding output port and the center point. The third bending portion is provided between the third feeding output port and the center point. The fourth bending portion is provided between the fourth feeding output port and the center point. The first bending portion to the fourth bending portion have the same wiring pattern and are arranged to be rotationally symmetric about the center point.

4. The differential feeding network according to claim 1, wherein The first feeder includes a first part between the first feeding output port and the center point, and a second part between the second feeding output port and the center point, and the first part includes a fifth bending portion. The second feeder includes a third part between the third feeding output port and the center point, and a fourth part between the fourth feeding output port and the center point, and the third part includes a sixth bending portion. The first part of the first feeder and the fourth part of the second feeder form a first pattern, the third part of the second feeder and the second part of the first feeder form a second pattern, and the first pattern and the second pattern are symmetric to each other.

5. The differential feeding network according to claim 1, wherein The first feeder includes a first portion located between the first feed output port and the center point, and a second portion located between the second feed output port and the center point, and the first portion and the second portion are not on the same straight line. The second feeder includes a third portion located between the third feed output port and the center point, and a fourth portion located between the fourth feed output port and the center point, and the third portion and the fourth portion are not on the same straight line. The first portion of the first feeder and the fourth portion of the second feeder form a third pattern, the third portion of the second feeder and the second portion of the first feeder form a fourth pattern, and the third pattern and the fourth pattern are symmetric to each other.

6. The differential feeding network according to claim 1, further comprising four L-shaped feed coupling components respectively electrically connected to the first feed output port to the fourth feed output port, wherein each L-shaped feed coupling component includes a vertical portion and a horizontal portion. One end of the vertical portion is connected to one end of the horizontal portion, and the other end of the vertical portion is connected to one of the first feed output port to the fourth feed output port. The horizontal portion extends in a direction towards the center point, and the extension length of the horizontal portion is less than the distance between one of the first feed output port to the fourth feed output port and the center point.

7. The differential feeding network according to claim 6, wherein, The vertical portion has a cylindrical shape.

8. The differential feeding network according to any one of claims 1 to 7, wherein The differential feeding network is formed of a metallic material.

9. A matrix-type differential feeding network, comprising a plurality of unit differential feeding networks arranged in a matrix, the unit differential feeding network including the differential feeding network according to any one of claims 1 to 8, wherein the first input feeders of at least two unit differential feeding networks located in the same column are electrically connected to each other and the second input feeders are electrically connected to each other, and the at least two unit differential feeding networks are fed through the same first feed input port and the same second feed input port.

10. An antenna, comprising a metallic radiation patch, a differential feeding network, and a metallic reflector, the differential feeding network including the differential feeding network according to any one of claims 1 to 5. The metallic radiation patch is disposed above the differential feeding network, and the differential feeding network is disposed above the metallic reflector. The antenna further includes a connection structure disposed between the metallic radiation patch and the differential feeding network.

11. The antenna according to claim 10, wherein, The connection structure includes four metal posts respectively electrically connected to the first feed output port to the fourth feed output port. One end of each metal post is electrically connected to one of the first feed output port to the fourth feed output port, and the other end of each metal post is electrically connected to a corresponding feeding position on the metallic radiation patch.

12. The antenna according to claim 10, wherein, The differential feeding network further includes four L-shaped feed coupling components respectively electrically connected to the first feed output port to the fourth feed output port. Each L-shaped feed coupling component includes a vertical portion and a horizontal portion. One end of the vertical part is connected to one end of the horizontal part, and the other end of the vertical part is connected to one of the first feed output port to the fourth feed output port. The horizontal part extends in the direction towards the center point, and the extension length of the horizontal part is less than the distance between one of the first feed output port to the fourth feed output port and the center point. The connection structure includes a central connecting post. One end of the central connecting post is connected to the center point, the other end of the central connecting post is connected to the center of the metal radiation patch, and the height of the central connecting post is greater than the height of the vertical part.

13. The antenna according to claim 12, wherein, The central connecting post is formed of a metal material, or the central connecting post is formed of a non-metal material.

14. The antenna according to any one of claims 10 to 13, wherein, A grounded short circuit point is provided at the center point of the differential feed network.

15. The antenna according to claim 10, wherein, The metal radiation patch has at least one of the following structures: a groove, a bend or a droop.

16. The antenna according to claim 10, wherein, The metal radiation patch has a stacked structure of multiple patches.

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