Circularly polarized antenna

Abstract

The present invention discloses a circularly polarized antenna, which includes a dielectric plate, a metal floor, a first radiation arm, a second radiation arm, a feed, a first conductive post and a second conductive post. The metal floor is arranged at an interval from the dielectric plate. The first radiation arm and the second radiation arm are symmetrically distributed about the center on the dielectric plate. The feed is arranged at the symmetric center position of the first radiation arm and the second radiation arm. The first conductive post and the second conductive post are symmetrically distributed about the symmetric center position. The first conductive post is used for electrically connecting the first radiation arm and the metal floor, and the second conductive post is used for electrically connecting the second radiation arm and the metal floor. The circularly polarized antenna of the present invention can improve the phase stability of the antenna and can also realize the miniaturization of the antenna.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and in particular, to a circularly polarized antenna. Background Art

[0002] In the related art, the axial ratio and phase stability index of a circularly polarized antenna determine the overall accuracy of antenna positioning, and the positioning accuracy of the current circularly polarized antenna still needs to be improved; with the development of technology, higher requirements are also put forward for the miniaturization of antennas. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems in the related art to some extent.

[0004] An embodiment of the present invention provides a circularly polarized antenna, which can improve the phase stability of the antenna, improve the positioning accuracy of the antenna; and realize the miniaturization of the antenna.

[0005] The circularly polarized antenna according to an embodiment of the present invention includes a dielectric plate; a metal floor, the metal floor is arranged at an interval from the dielectric plate; a first radiation arm and a second radiation arm, both the first radiation arm and the second radiation arm are arranged on the outer side surface of the dielectric plate facing away from the metal floor, and the first radiation arm and the second radiation arm are symmetrically distributed about the center; a feed, the feed is arranged at the symmetric center position of the first radiation arm and the second radiation arm, the feed has a positive electrode and a negative electrode, one of the first radiation arm and the second radiation arm is connected to the positive electrode of the feed, and the other is connected to the negative electrode of the feed; a first conductive column and a second conductive column, the first conductive column and the second conductive column are symmetrically distributed about the symmetric center position, the first conductive column and the second conductive column are arranged between the dielectric plate and the metal floor, the first end of the first conductive column is electrically connected to the first radiation arm, the second end of the first conductive column is electrically connected to the metal floor, the first end of the second conductive column is electrically connected to the second radiation arm, and the second end of the second conductive column is electrically connected to the metal floor.

[0006] The circularly polarized antenna according to an embodiment of the present invention can improve the phase stability of the antenna, improve the positioning accuracy of the antenna; and realize the miniaturization of the antenna.

[0007] In some embodiments, the circularly polarized antenna further includes a parasitic metal sheet, the parasitic metal sheet is arranged on the dielectric plate, and the parasitic metal sheet is arranged at an interval from the first radiation arm, the second radiation arm, the first conductive column, and the second conductive column.

[0008] In some embodiments, the parasitic metal sheet is arranged at the position of the weak electric potential of the electric field formed by the first radiation arm and the second radiation arm.

[0009] In some embodiments, there are a plurality of parasitic metal sheets, and the plurality of parasitic metal sheets are arranged on the outer peripheral sides of the first radiation arm and the second radiation arm. The plurality of parasitic metal sheets are arranged at intervals along the circumferential direction of the dielectric plate and are symmetrically distributed about the central symmetry position.

[0010] In some embodiments, the metal floor is of a back cavity structure, and one side of the metal floor has an opening, and the dielectric plate is arranged at the opening position of the metal floor.

[0011] In some embodiments, at least part of the parasitic metal sheets are connected to the metal floor.

[0012] In some embodiments, the circularly polarized antenna further includes a first circuit element and a second circuit element. The first circuit element is connected between the first radiation arm and the first conductive post, and the second circuit element is connected between the second radiation arm and the second conductive post.

[0013] In some embodiments, the first circuit element and the second circuit element are inductors or capacitors or resistors.

[0014] In some embodiments, the first radiation arm includes a first section and a second section. The width dimension L1 of the first section is greater than the width dimension L2 of the second section. The first section is located between the second section and the first conductive post. The second radiation arm includes a third section and a fourth section. The width dimension L3 of the third section is greater than the width dimension L4 of the fourth section. The third section is located between the fourth section and the second conductive post.

[0015] In some embodiments, there are a plurality of dielectric plates, and the plurality of dielectric plates are stacked and arranged. Description of the Drawings

[0016] Figure 1 is a schematic diagram of a circularly polarized antenna according to an embodiment of the present invention.

[0017] Figure 2 is a top view of a left-handed circularly polarized antenna according to an embodiment of the present invention.

[0018] Figure 3 is a top view of a right-handed circularly polarized antenna according to an embodiment of the present invention.

[0019] Figure 4 is a schematic diagram of a circularly polarized antenna according to another embodiment of the present invention.

[0020] Figure 5 is a top view of a circularly polarized antenna according to an embodiment of the present invention.

[0021] Figure 6It is the axial ratio simulation diagram of the circularly polarized antenna according to an embodiment of the present invention.

[0022] Figure 7 It is the electric field distribution diagram of the circularly polarized antenna according to an embodiment of the present invention.

[0023] Reference numerals:

[0024] Dielectric plate 1; metal floor 2; first radiation arm 3; first section 31; second section 32; second radiation arm 4; third section 41; fourth section 42; feed 5; first conductive post 6; second conductive post 7; parasitic metal sheet 8; first circuit element 9; second circuit element 10. Detailed implementation manners

[0025] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the drawings. The embodiments described below by referring to the drawings are exemplary and are intended to explain the present invention and should not be construed as limiting the present invention.

[0026] As Figure 1 shown, the circularly polarized antenna according to an embodiment of the present invention includes a dielectric plate 1, a metal floor 2, a first radiation arm 3, a second radiation arm 4, a feed 5, a first conductive post 6, and a second conductive post 7.

[0027] As Figure 1 shown, the dielectric plate 1 may be a square circuit board. In other embodiments, the dielectric plate 1 may also be a circular plate.

[0028] The metal floor 2 is arranged at an interval from the dielectric plate 1. As Figure 1 shown, the metal floor 2 may be a copper plate. The metal floor and the dielectric plate are arranged at an interval in the up and down direction, and the metal floor 2 is provided below the dielectric plate 1. It can be understood that in other embodiments, the metal floor 2 may also be made of a material with a relatively low resistance such as copper alloy or aluminum alloy.

[0029] Both the first radiation arm 3 and the second radiation arm 4 are provided on the outer side surface of the dielectric plate 1 facing away from the metal floor 2, and the first radiation arm 3 and the second radiation arm 4 are symmetrically distributed about the center. As Figure 1 shown, the outer side surface of the dielectric plate is the upper surface of the dielectric plate. Both the first radiation arm and the second radiation arm are provided on the upper surface of the dielectric plate. The first radiation arm 3 and the second radiation arm 4 have the same shape, and the first radiation arm 3 and the second radiation arm 4 are symmetrically distributed about the center, and the center of symmetry of the two is the center of the dielectric plate 1.

[0030] The feed 5 is provided at the center of symmetry of the first radiation arm 3 and the second radiation arm 4. The feed 5 has a positive electrode and a negative electrode. One of the first radiation arm 3 and the second radiation arm 4 is connected to the positive electrode of the feed 5, and the other is connected to the negative electrode of the feed 5.

[0031] AsFigure 1 As shown, the feed 5 can be arranged at the center of the dielectric plate 1, and the positive electrode of the feed 5 is electrically connected to the first radiation arm 3, and the negative electrode of the feed 5 is electrically connected to the second radiation arm 4. It can be understood that in other embodiments, the positive electrode of the feed 5 can be electrically connected to the second radiation arm 4, and the negative electrode of the feed 5 can be electrically connected to the first radiation arm 3.

[0032] The first conductive post 6 and the second conductive post 7 are symmetrically distributed about the center position. The first conductive post 6 and the second conductive post 7 are arranged between the dielectric plate 1 and the metal floor 2. The first end of the first conductive post 6 is electrically connected to the first radiation arm 3, the second end of the first conductive post 6 is electrically connected to the metal floor 2, the first end of the second conductive post 7 is electrically connected to the second radiation arm 4, and the second end of the second conductive post 7 is electrically connected to the metal floor 2.

[0033] As Figure 1 shown, the first conductive post 6 and the second conductive post 7 have the same shape. The first conductive post 6 and the second conductive post 7 are arranged between the dielectric plate 1 and the metal floor 2. Both the first conductive post and the second conductive post extend along the up and down direction. The upper end of the first conductive post 6 is electrically connected to the first radiation arm 3, and the lower end of the first conductive post 6 is electrically connected to the metal floor 2. The upper end of the second conductive post is electrically connected to the second radiation arm 4, and the lower end of the second conductive post 7 is electrically connected to the metal floor 2. The first conductive post 6 and the second conductive post 7 are centrosymmetric, and the center of symmetry between them is at the center of the dielectric plate 1.

[0034] For the circularly polarized antenna according to the embodiment of the present invention, since the first radiation arm 3 and the second radiation arm 4 are centrosymmetric, the phases of two mutually perpendicular current components of the electric field generated by the antenna differ by 90 degrees, and circular polarization of the antenna can be realized. By adjusting the arrangement orientations of the first radiation arm and the second radiation arm, left-handed circular polarization and right-handed circular polarization can be respectively realized. For example, Figure 2 shown is the left-handed circularly polarized antenna according to the embodiment of the present invention, Figure 3 shown is the right-handed circularly polarized antenna according to the embodiment of the present invention.

[0035] Since the antenna is electrically connected to the metal floor 2 through the first conductive post 6 and the second conductive post 7, the resonant size of the antenna can be increased, thereby realizing miniaturization of the antenna. It can also mitigate the deterioration of the antenna pattern caused by the imbalance of the feed 5, have better port matching, and have a better axial ratio. Due to the symmetry of the antenna structure, the phase stability of the antenna can also be improved, thereby improving the positioning accuracy of the antenna. As Figure 6 shown, Figure 6 in which the abscissa represents the bandwidth and the ordinate represents the axial ratio. The antenna achieves an axial ratio of less than 3 dB within the bandwidth; at the same time, the phase stability of the antenna achieves an accuracy of plus or minus 0.5 mm. Compared with the accuracy of plus or minus 2 mm in the prior art, the improvement effect of the accuracy is obvious.

[0036] In some embodiments, the circularly polarized antenna further includes a parasitic metal sheet 8, which is disposed on the dielectric substrate 1, and the parasitic metal sheet 8 is spaced apart from the first radiation arm 3, the second radiation arm 4, the first conductive post 6, and the second conductive post 7.

[0037] As Figure 1 shown, the parasitic metal sheet 8 can be disposed on the upper surface of the dielectric substrate 1, and the parasitic metal sheet 8 is spaced apart from the first radiation arm 3, the second radiation arm 4, the first conductive post 6, and the second conductive post 7. The parasitic metal sheet 8 can reduce the current attenuation of the antenna, achieve uniform radiation of the antenna aperture, reduce the fluctuation range of the antenna phase center, improve the axial ratio characteristic of the wide elevation angle, and improve the phase stability.

[0038] Preferably, the parasitic metal sheet 8 is disposed at the position of the weak electric potential of the electric field formed by the first radiation arm 3 and the second radiation arm 4.

[0039] Specifically, as Figure 7 shown, when the circularly polarized antenna operates, the electric field intensity on the first radiation arm and the second radiation arm is relatively strong, and the electric field in the space around the first radiation arm and the second radiation arm is relatively weak and constitutes the position of the weak electric potential of the electric field. The parasitic metal sheet 8 is disposed at the weak electric potential of the electric field of the circularly polarized antenna, and the effect of reducing the antenna current attenuation is obvious, and the radiation of the antenna aperture is more uniform.

[0040] In some embodiments, there are multiple parasitic metal sheets 8, and the multiple parasitic metal sheets 8 are disposed on the outer peripheral sides of the first radiation arm 3 and the second radiation arm 4, and the multiple parasitic metal sheets 8 are spaced apart along the circumferential direction of the dielectric substrate 1 and are centrosymmetrically distributed about the center of symmetry.

[0041] Specifically, as Figure 1 shown, there are 4 parasitic metal sheets, and the 4 parasitic metal sheets 8 are distributed on the outer peripheral sides of the first radiation arm 3 and the second radiation arm 4. The 4 parasitic metal sheets 8 are spaced apart along the circumferential direction of the dielectric substrate 1 and are respectively disposed at the diagonal positions of the dielectric substrate, and any two diagonally distributed parasitic metal sheets are centrosymmetrically distributed about the center of the dielectric substrate. In some embodiments, the parasitic metal sheet 8 can have 2, 6, etc.

[0042] In some embodiments, the metal floor 2 is a back cavity type, and one side of the metal floor 2 has an opening, and the dielectric substrate 1 is disposed at the opening position of the metal floor 2.

[0043] Specifically, as Figure 4As shown, the metal floor is in the shape of a square box. The metal bottom plate includes a square bottom plate and four side plates. The four side plates are all at the four edge positions of the square bottom plate, and any two adjacent side plates are connected. The metal floor 2 has an opening on one side, and the dielectric plate 1 is fixed at the opening of the metal floor 2 through a snap fit with a card slot. The first conductive post 6 and the second conductive post 7 are both electrically connected to the square bottom plate of the metal floor. The metal floor 2 is of the back cavity type, which can improve the structural strength of the antenna.

[0044] In some embodiments, at least a part of the parasitic metal sheet 8 is connected to the metal floor 2.

[0045] As Figure 4 shown, there are multiple parasitic metal sheets 8, and they are arranged around the outer peripheral sides of the first radiation arm and the second radiation arm. One side of the parasitic metal sheet 8 is flush with the edge of the dielectric plate 1 and is connected to the corresponding side plate of the metal floor. The parasitic metal sheet 8 can improve the axial ratio of the antenna in the wide elevation angle.

[0046] In some embodiments, the circularly polarized antenna further includes a first circuit element 9 and a second circuit element 10. The first circuit element 9 is connected between the first radiation arm 3 and the first conductive post 6, and the second circuit element 10 is connected between the second radiation arm 4 and the second conductive post 7.

[0047] Specifically, as Figure 1 shown, the first circuit element 9 is connected between the first radiation arm 3 and the first conductive post 6, and the second circuit element 10 is connected between the second radiation arm 4 and the second conductive post 7. The first circuit element 9 and the second circuit element 10 can be resistors. The first circuit element 9 and the second circuit element 10 can achieve miniaturization of the antenna by dissipating the reflected wave. In other embodiments, the first circuit element 9 and the second circuit element 10 can also be capacitors or inductors, and the miniaturization of the antenna can be achieved by enabling the circularly polarized antenna to operate in a lower frequency band.

[0048] In some embodiments, the first radiation arm 3 includes a first section 31 and a second section 32. The width dimension L1 of the first section 31 is greater than the width dimension L2 of the second section 32. The first section 31 is located between the second section 32 and the first conductive post 6. The second radiation arm 4 includes a third section 41 and a fourth section 42. The width dimension L3 of the third section 41 is greater than the width dimension L4 of the fourth section 42. The third section 41 is located between the fourth section 42 and the second conductive post 7.

[0049] Specifically, as Figure 5As shown, the width dimension L1 of the first section 31 is greater than the width dimension L2 of the second section 32. The second section 32 is located at one end of the first radiation arm 3 away from the first conductive post 6. One end of the first section 31 is connected to the second section 32, and the other end is electrically connected to the first conductive post 6. The fourth section 42 is located at one end of the second radiation arm 4 away from the second conductive post 7. One end of the third section 41 is connected to the fourth section 42, and the other end is electrically connected to the fourth conductive post. Arranging the first section 31 and the second section 32, and the third section 41 and the fourth section 42 can make the central symmetry characteristics of the first radiation arm 3 and the second radiation arm 4 obvious.

[0050] In some embodiments, there are multiple dielectric plates 1, and the multiple dielectric plates 1 are stacked and arranged.

[0051] The multiple dielectric plates 1 are stacked and arranged. The multiple dielectric plates 1 can be simply divided into an upper layer, a middle layer, and a lower layer. The parasitic metal sheet 8 is provided on the upper layer of the dielectric plate 1. It can be understood that the parasitic metal sheet 8 can also be provided on the middle layer or the lower layer of the dielectric plate 1.

[0052] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention.

[0053] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, "a plurality" means at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0054] In the present invention, unless otherwise clearly specified and limited, the terms "mounted", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection, an electrical connection, or communicable with each other; it can be directly connected, or indirectly connected through an intermediate medium, and can be the communication inside two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0055] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the horizontal height of the first feature is less than that of the second feature.

[0056] In the description of this specification, the description of reference terms such as "an embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, 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, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0057] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A circularly polarized antenna, characterized in that, comprising: a dielectric plate; a metal floor, the metal floor being arranged at an interval from the dielectric plate; a first radiation arm and a second radiation arm, both the first radiation arm and the second radiation arm being provided on the outer side surface of the dielectric plate facing away from the metal floor, and the first radiation arm and the second radiation arm being symmetrically distributed about the center; a feed, the feed being provided at the symmetric center position of the first radiation arm and the second radiation arm, the feed having a positive electrode and a negative electrode, one of the first radiation arm and the second radiation arm being connected to the positive electrode of the feed and the other being connected to the negative electrode of the feed; a first conductive post and a second conductive post, the first conductive post and the second conductive post being symmetrically distributed about the symmetric center position, the first conductive post and the second conductive post being provided between the dielectric plate and the metal floor, a first end of the first conductive post being electrically connected to the first radiation arm, a second end of the first conductive post being electrically connected to the metal floor, a first end of the second conductive post being electrically connected to the second radiation arm, and a second end of the second conductive post being electrically connected to the metal floor; further comprising a first circuit element and a second circuit element, the first circuit element being connected between the first radiation arm and the first conductive post, and the second circuit element being connected between the second radiation arm and the second conductive post.

2. The circularly polarized antenna according to claim 1, characterized in that, further comprising a parasitic metal sheet, the parasitic metal sheet being provided on the dielectric plate, and the parasitic metal sheet being arranged at an interval from the first radiation arm, the second radiation arm, the first conductive post, and the second conductive post.

3. The circularly polarized antenna according to claim 2, characterized in that, the parasitic metal sheet is provided at a position of weak electric potential of the electric field formed by the first radiation arm and the second radiation arm.

4. The circularly polarized antenna according to claim 3, characterized in that, there are a plurality of the parasitic metal sheets, the plurality of parasitic metal sheets being provided on the outer peripheral side of the first radiation arm and the second radiation arm, the plurality of parasitic metal sheets being arranged at intervals along the circumferential direction of the dielectric plate and being symmetrically distributed about the symmetric center position.

5. The circularly polarized antenna according to claim 2, characterized in that, the metal floor is a back cavity type, one side of the metal floor has an opening, and the dielectric plate is provided at the opening position of the metal floor.

6. The circularly polarized antenna according to claim 5, characterized in that, at least part of the parasitic metal sheets are connected to the metal floor.

7. The circularly polarized antenna according to claim 1, characterized in that, the first circuit element and the second circuit element are an inductor or a capacitor or a resistor.

8. The circularly polarized antenna according to claim 1, characterized in that, The first radiation arm includes a first section and a second section. A width dimension L1 of the first section is greater than a width dimension L2 of the second section. The first section is located between the second section and the first conductive column. The second radiation arm includes a third section and a fourth section. A width dimension L3 of the third section is greater than a width dimension L4 of the fourth section. The third section is located between the fourth section and the second conductive column.

9. The circularly polarized antenna according to any one of claims 1-8, characterized in that there are a plurality of dielectric plates, and the plurality of dielectric plates are stacked and arranged.

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