An antenna

Abstract

The present disclosure provides an antenna, comprising: a radiator, comprising a pair of radiating units, the radiating units being hollow structures; a feeding structure, the feeding structure being located inside the hollow structure of the radiating unit, the feeding structure comprising a first transmission branch, a second transmission branch and a short-circuit branch arranged in parallel, wherein the first transmission branch is connected to one of the paired radiating units for feeding, the second transmission branch is connected to the other of the paired radiating units for feeding, the short-circuit branch is connected to the first transmission branch at a first short-circuit portion, and the short-circuit branch is connected to the second transmission branch at a second short-circuit portion. The antenna of the present disclosure can avoid the generation of common mode current and realize balanced feeding.

Description

Technical Field

[0001] The present invention relates to the field of communication technology, and in particular to an antenna. Background Art

[0002] The balance of the antenna is determined by its radiation structure, feeding structure and electromagnetic environment. For the feeding structure, some commonly used feeding cables for antennas, such as coaxial cables, usually generate common-mode currents, which can be radiated and coupled to external noise sources, resulting in an increase in the cross-polarization of the antenna and a change in the shape of the radiation pattern, and the gain and efficiency of the antenna will also change. Summary of the invention

[0003] The present disclosure describes an antenna capable of achieving balanced feeding.

[0004] According to various aspects of the present disclosure, an antenna includes: a radiator, which includes a pair of radiating units, and the radiating units are hollow structures; a feeding structure, which is located inside the hollow structure of the radiating unit, and includes a first transmission branch node, a second transmission branch node and a short-circuit branch node arranged in parallel, wherein the first transmission branch node is connected to one of the paired radiating units for feeding, the second transmission branch node is connected to the other of the paired radiating units for feeding, the short-circuit branch node is connected to the first transmission branch node at a first short-circuit portion, and the short-circuit branch node is connected to the second transmission branch node at a second short-circuit portion.

[0005] According to one embodiment of the antenna, the second transmission stub and the short-circuit stub are arranged symmetrically with respect to the first transmission stub.

[0006] According to one embodiment of the antenna, the antenna is a dipole antenna, and the feeding structure is arranged along the axial direction of the radiation element of the dipole antenna.

[0007] According to one embodiment of the antenna, the radiation element is a conical hollow structure.

[0008] According to an embodiment of the antenna, the first transmission branch and the second transmission branch are respectively connected to the corresponding radiation element via a strip line.

[0009] According to one embodiment of the antenna, the feeding structure is connected to the coaxial cable, wherein the first transmission branch is connected to the inner conductor of the coaxial cable, the second transmission branch is connected to the outer conductor of the coaxial cable, and the short-circuit branch is connected to the outer conductor of the coaxial cable.

[0010] According to one embodiment of the antenna, the second transmission branch and the short-circuit branch have an impedance gradient section at one end connected to the outer conductor of the coaxial cable.

[0011] According to an embodiment of the antenna, the impedance gradient section is realized by gradient line width.

[0012] According to an embodiment of the antenna, the feeding structure is disposed on a multi-layer PCB board, wherein the first transmission branch node, the second transmission branch node and the short-circuit branch node are respectively located on different metal layers of the PCB board.

[0013] According to one embodiment of the antenna, the short-circuit stub is connected to the second transmission stub at the second short-circuit portion through a plurality of metal vias, and the second short-circuit portion extends to the connection between the short-circuit stub and the second transmission stub and the outer conductor of the coaxial cable.

[0014] The antenna disclosed in the present invention can avoid the generation of common mode current and achieve balanced feeding. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 Schematic diagram of an axonometric view of an antenna according to an embodiment of the present disclosure.

[0016] Figure 2 is a perspective schematic diagram of an antenna according to an embodiment of the present disclosure.

[0017] Figure 3 It is a front view schematic diagram of a feeding structure of an antenna involved in one embodiment of the present disclosure.

[0018] Figure 4 It is an isometric schematic diagram of a feeding structure of an antenna involved in one embodiment of the present disclosure.

[0019] Figure 5 It is a side view schematic diagram of a feeding structure of an antenna involved in one embodiment of the present disclosure.

[0020] Figure 6 It is a partial isometric schematic diagram of a feeding structure of an antenna involved in one embodiment of the present disclosure. DETAILED DESCRIPTION

[0021] The following describes the embodiments with reference to the accompanying drawings. It should be understood that the drawings are not necessarily to scale. The described embodiments are exemplary and the features of the embodiments may be combined or substituted in the same or similar manner.

[0022] The balance of the antenna is determined by its radiation structure, feeding structure and electromagnetic environment. In the related art, some commonly used feeding cables for antennas, such as coaxial cables, usually generate common-mode currents. For example, for coaxial cables, the current from the inner conductor of the coaxial cable is equal to the current from the outer conductor, but in opposite directions. However, due to the different resistances to ground between the inner conductor and the outer conductor, when the coaxial cable is directly connected to the antenna, the current from the outer conductor will diffuse to the outside of the coaxial cable, which generates common-mode currents. Common-mode currents can radiate and couple to external noise sources, which leads to an increase in the cross-polarization of the antenna and a change in the shape of the radiation pattern, and the gain and efficiency of the antenna will also change.

[0023] According to an antenna involved in one embodiment of the present disclosure, Figures 1 to 6 As shown, the antenna includes:

[0024] A radiator, the radiator comprising a pair of radiating units 100, the radiating units 100 being hollow structures;

[0025] A feeding structure, the feeding structure is located inside the hollow structure of the radiation unit 100, and the feeding structure includes a first transmission branch node 201, a second transmission branch node 202 and a short-circuit branch node 203 arranged in parallel, wherein the first transmission branch node 201 is connected to one of the paired radiation units 100 to feed it, the second transmission branch node 202 is connected to the other of the paired radiation units 100 to feed it, the short-circuit branch node 203 is connected to the first transmission branch node 201 at a first short-circuit portion 203A, and the short-circuit branch node 203 is connected to the second transmission branch node 202 at a second short-circuit portion 203B.

[0026] In this embodiment, the feeding structure is located inside the hollow structure of the radiating unit, which is equivalent to the feeding part being shielded by the radiating unit and not radiating outward, thereby avoiding the feeding structure from affecting the radiation pattern of the antenna. The three parts in the feeding structure are arranged in parallel, that is, they are arranged as a multi-layer stacked structure, which takes into account the symmetry and compactness of the structure, and the compact feeding structure can reduce the energy coupling that may exist between the feeding structure and the radiating unit. In addition, the first transmission branch and the second transmission branch used for feeding are electrically connected to the short-circuit branch respectively, that is, the two are connected through the short-circuit branch, so that the voltage at the second short-circuit part is zero, which is the same potential. Therefore, the feeding structure will not generate common mode current, realize balanced feeding, avoid or reduce the adverse effects of unbalanced feeding on the radiation pattern, gain and efficiency of the antenna, and can meet some application scenarios that have strict requirements on the performance of the antenna, such as calibration, which requires the antenna to meet a certain bandwidth and gain, and have good symmetry.

[0027] In this embodiment, the radiator of the antenna has a pair of radiating units. It is understood that the number of radiating units may not be limited thereto. In some other embodiments, the antenna may have two or more pairs of radiating units, and for the two or more pairs of radiating units, for example, power feeding may be achieved through a power divider.

[0028] Optionally, refer to Figures 4 to 6 The second transmission branch 202 and the short-circuit branch 203 are symmetrically arranged relative to the first transmission branch 201, further enhancing the symmetry of the feeding structure.

[0029] Optionally, refer to Figures 1-2 , the antenna is a dipole antenna, and the feeding structure is arranged along the axial direction of the radiation unit 100 of the dipole antenna, that is, the feeding mode is side feeding. Figures 1-2 The radiation unit 100 is a conical hollow structure, which is narrow in the center and wide at the end. The conical structure can be used to increase the bandwidth of the antenna, and on the other hand, the wider end is farther away from the feeding structure, so the energy coupling between the radiation unit 100 and the feeding structure is correspondingly smaller.

[0030] Optionally, refer to Figures 3-4 The first transmission branch 201 and the second transmission branch 202 are respectively connected to the corresponding radiation unit (not shown in the figure) through a strip line 300. The two strip lines form a parallel strip line, so that the first and second transmission branches feed the radiation unit after the parallel strip line transition. Since the current near the feeding point is strong, the transition of the strip line can reduce the influence between the feeding structure and the feeding point.

[0031] Reference Figure 2 In some embodiments, the feed structure is connected to the coaxial cable 400. Specifically, the first transmission branch is connected to the inner conductor of the coaxial cable, the second transmission branch is connected to the outer conductor of the coaxial cable, and the short-circuit branch is connected to the outer conductor of the coaxial cable. Figure 4 The second transmission branch 202 and the short-circuit branch 203 have an impedance gradient section at one end connected to the outer conductor of the coaxial cable. The impedance gradient section is realized by, for example, a line width gradient, which smoothly transitions from a wide line width at the end connected to the outer conductor to a narrow line width. When the line width is wider, the electric field is mainly distributed inside the feeding structure, and the surface current is very small, so the common mode current on the surface of the outer conductor of the coaxial cable can be further reduced.

[0032] like Figure 3 As shown, in some embodiments, the feeding structure is disposed on a multi-layer PCB board 500. Figures 4 to 6For a clearer display, the dielectric board is omitted in the figure. The first transmission branch 201, the second transmission branch 202 and the short-circuit branch 203 are respectively located on different metal layers of the PCB. The multi-layer PCB makes the feeding structure compact through the stacked structure. On the other hand, it has a certain shielding effect, which can prevent the low-level radiation that may be generated by the feeding structure from causing adverse effects on the radiation unit that accommodates the feeding structure, causing an unbalanced electromagnetic environment. Figures 4 to 6 Optionally, the short-circuit branch 203 is connected to the second transmission branch 202 at the second short-circuit portion 203B through multiple metal vias, and the second short-circuit portion 203B extends to the connection point between the short-circuit branch 203 and the second transmission branch 202 and the outer conductor of the coaxial cable (not shown in the figure), and this part forms a cylindrical structure / quasi-coaxial structure with a certain length to form a transmission transition.

[0033] In the above description, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present disclosure. In the present disclosure, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0034] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present disclosure, "plurality" means at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0035] Although the embodiments of the present disclosure have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present disclosure. A person skilled in the art may change, modify, substitute and vary the above embodiments within the scope of the present disclosure.

Claims

1. An antenna, characterized in that: include: A radiator, the radiator comprising a pair of radiating units, the radiating units being hollow structures; A feeding structure, the feeding structure is located inside the hollow structure of the radiating unit, the feeding structure comprises a first transmission branch node, a second transmission branch node and a short-circuit branch node which are arranged in parallel, wherein the first transmission branch node is connected to one of the paired radiating units for feeding, the second transmission branch node is connected to the other of the paired radiating units for feeding, the short-circuit branch node is connected to the first transmission branch node at a first short-circuit portion, and the short-circuit branch node is connected to the second transmission branch node at a second short-circuit portion; The feeding structure is connected to the coaxial cable, wherein the first transmission branch is connected to the inner conductor of the coaxial cable, the second transmission branch is connected to the outer conductor of the coaxial cable, and the short-circuit branch is connected to the outer conductor of the coaxial cable; The feeding structure is arranged on a multi-layer PCB board, wherein the first transmission branch node, the second transmission branch node and the short-circuit branch node are respectively located on different metal layers of the PCB board.

2. The antenna according to claim 1, characterized in that The second transmission branch node and the short-circuit branch node are symmetrically arranged relative to the first transmission branch node.

3. The antenna according to claim 1, characterized in that The antenna is a dipole antenna, and the feeding structure is arranged along the axial direction of the radiation unit of the dipole antenna.

4. The antenna according to claim 3, characterized in that: The radiation unit is a conical hollow structure.

5. The antenna according to claim 1, characterized in that: The first transmission branch section and the second transmission branch section are respectively connected to the corresponding radiation unit through a strip line.

6. The antenna according to claim 1, characterized in that The ends of the second transmission branch and the short-circuit branch connected to the outer conductor of the coaxial cable have impedance gradient sections.

7. The antenna according to claim 6, characterized in that The impedance gradient section is realized by gradient line width.

8. The antenna according to claim 1, characterized in that: The short-circuit branch is connected to the second transmission branch at the second short-circuit portion through a plurality of metal vias, and the second short-circuit portion extends to the connection point between the short-circuit branch and the second transmission branch and the outer conductor of the coaxial cable.

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