Circular polarization antenna unit and circular polarization antenna

Abstract

The present invention discloses a circular polarization antenna unit and a circular polarization antenna. The circular polarization antenna unit includes: a first metal layer; a dielectric layer, which is arranged below the first metal layer; a second metal layer, which is arranged below the dielectric layer; a feeding structure, which includes a feeding port, a radiator, a plurality of feeding transition pieces and a plurality of coaxial lines, wherein the second metal layer is formed with the feeding port, the feeding port and the feeding transition piece are connected through the coaxial line, and the feeding transition piece and the radiator are connected through the coaxial line. A circular polarization antenna unit of this structure is provided with a feeding transition piece, so that it is easier to achieve circular polarization when the excitation current from the feeding port reaches the radiator, and the effective radiation area is significantly increased, so that the circular polarization antenna unit can achieve high gain and low axial ratio.

Description

Technical Field

[0001] The invention relates to the technical field of satellite communications, and in particular to a circular polarization antenna unit and a circular polarization antenna. Background Art

[0002] With the rapid development of satellite communications and mobile communications, antennas are an important part of the communication system, and their performance is directly related to the quality of the entire system, so higher requirements are placed on the radiation characteristics of antennas. Since the circularly polarized antenna unit isolates the left and right polarized waves from each other and does not receive each other, that is, the rotation direction is orthogonal, and the rotation direction will be reversed when incident on a symmetrical target, it has weaker multipath effects and stronger suppression of rain and fog interference. Therefore, circularly polarized waves are generally used as satellite navigation signals in satellite navigation and positioning systems. In order to receive as many satellite signals as possible and obtain a better signal-to-noise ratio, the satellite navigation and positioning system requires that the antenna not only has wide-angle circular polarization coverage, but also must have higher low-elevation angle gain and wider beam width.

[0003] The prior art discloses a circularly polarized antenna, which discloses that a single-arm planar printed spiral radiator is arranged on the uppermost dielectric substrate, the lower side of the second dielectric substrate is a floor, the third dielectric substrate is arranged with an electromagnetic coupling feeding mechanism, and the fourth dielectric substrate is arranged with a microstrip line to stripline electromagnetic coupling feeding mechanism, wherein the single-arm planar printed spiral radiator is directly excited by a cylindrical probe, the cylindrical probe is interconnected with the microstrip line, and the electromagnetic coupling feeding mechanism arranged on the third dielectric substrate adopts an electromagnetic coupling method of a rectangular gap, and electromagnetic energy is coupled to the microstrip line above the floor.

[0004] However, the above circularly polarized antenna is limited by the arrangement of the radiation patch and is not conducive to achieving high gain of the circularly polarized antenna. Summary of the invention

[0005] Therefore, the technical problem to be solved by the present invention is to overcome the defect in the prior art that the circularly polarized antenna is limited by the setting of the radiation patch and is not conducive to the circularly polarized antenna to achieve high gain, thereby providing a circularly polarized antenna unit.

[0006] A circular polarization antenna unit, comprising:

[0007] A first metal layer;

[0008] a dielectric layer, disposed below the first metal layer;

[0009] A second metal layer, which is disposed below the dielectric layer;

[0010] A feeding structure comprises a feeding port, a radiator, a plurality of feeding transition pieces and a plurality of coaxial lines, wherein the feeding port is formed on the second metal layer, the feeding port and the feeding transition piece are connected through the coaxial line, and the feeding transition piece and the radiator are connected through the coaxial line.

[0011] Furthermore, a plurality of the feed transition pieces are provided, and adjacent feed transition pieces are connected via the coaxial line.

[0012] Furthermore, one feed transition piece is provided, two coaxial lines are provided, the feed port and one end of the feed transition piece are connected through the coaxial line, and the other end of the feed transition piece and the radiator are connected through the coaxial line.

[0013] Furthermore, the feed transition piece includes a transition lead-out portion and a transition connection portion, wherein one of the transition lead-out portions is connected to the feed port, and one of the transition connection portions is connected to the radiator.

[0014] Furthermore, the transition connection portion is an arc-shaped structure, and the arc-shaped structure is arranged to protrude outward; the transition lead-out portion is a linear structure.

[0015] Furthermore, the feed transition piece and the radiator are planar metal patches.

[0016] Furthermore, it also includes an isolation structure, which includes an isolation cavity and an isolation layer, wherein the first metal layer, the dielectric layer and the second metal layer are provided with an isolation cavity, and the isolation layer is provided on the cavity wall of the isolation cavity, wherein the isolation cavity is filled with an isolation medium, and the radiator is exposed from the isolation medium.

[0017] Furthermore, the isolation layer is also arranged on the upper wall surface of the first metal layer.

[0018] A circular polarization antenna comprises a plurality of the circular polarization antenna units mentioned above.

[0019] Furthermore, the circularly polarized antenna units are arranged in an N×N array, where N is a natural number.

[0020] The technical solution of the present invention has the following advantages:

[0021] 1. A circularly polarized antenna unit provided by the present invention comprises: a first metal layer; a dielectric layer, which is arranged below the first metal layer; a second metal layer, which is arranged below the dielectric layer; a feeding structure, which comprises a feeding port, a radiator, a plurality of feeding transition pieces and a plurality of coaxial lines, wherein the second metal layer is formed with the feeding port, the feeding port and the feeding transition piece are connected through the coaxial line, and the feeding transition piece and the radiator are connected through the coaxial line. A circularly polarized antenna unit of this structure is provided with a feeding transition piece, so that when the excitation current from the feeding port reaches the radiator, circular polarization is more easily achieved, and the effective radiation area is significantly increased, so that the circularly polarized antenna unit can achieve high gain and low axial ratio.

[0022] 2. A circularly polarized antenna unit provided by the present invention further includes an isolation structure, which includes an isolation cavity and an isolation layer, wherein the first metal layer, the dielectric layer and the second metal layer are provided with an isolation cavity, and the isolation layer is provided on the cavity wall of the isolation cavity, wherein the isolation cavity is filled with an isolation medium, and the radiator is provided to be exposed from the isolation medium. A circularly polarized antenna unit of this structure effectively improves the isolation between circularly polarized antenna units by providing an isolation structure, so as to realize the expansion of the circularly polarized antenna unit.

[0023] 3. The circular polarization antenna provided by the present invention comprises a plurality of the circular polarization antenna units mentioned above. Since the circular polarization antenna of this structure comprises the circular polarization antenna units mentioned above, it naturally has the advantages brought by the circular polarization antenna units mentioned above.

[0024] 4. The present invention provides a circularly polarized antenna, wherein the circularly polarized antenna units are arranged in an N×N array, where N is a natural number. When a circularly polarized antenna of this structure is arranged in a regular shape such as a rectangular parallelepiped, it is convenient to arrange the circularly polarized antenna units, thereby realizing an antenna array with more units. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the specific implementation methods of the present invention or the technical solutions in the prior art, the drawings required for use in the specific implementation methods or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0026] Figure 1 This is a schematic structural diagram of the circularly polarized antenna unit provided in Embodiment 1 and Embodiment 2 of the present invention when N=1;

[0027] Figure 2 for Figure 1A top view of the circularly polarized antenna unit shown when N=1;

[0028] Figure 3 for Figure 1 The simulation result diagram of |S11| for the circularly polarized antenna unit shown and when N=1;

[0029] Figure 4 for Figure 1 The gain simulation result diagram of the circularly polarized antenna unit when N=1 is shown;

[0030] Figure 5 for Figure 1 The axial ratio simulation result diagram of the circularly polarized antenna unit shown when N=1;

[0031] Figure 6 for Figure 1 The circularly polarized antenna unit shown and the directional pattern simulation result diagram when N=1;

[0032] Figure 7 This is a schematic structural diagram of the circularly polarized antenna unit provided in Embodiment 1 and Embodiment 2 of the present invention when N=2;

[0033] Figure 8 for Figure 7 A top view of the circularly polarized antenna unit shown when N=2;

[0034] Fig. 9 for Figure 7 The simulation result diagram of |S11| for the circularly polarized antenna unit shown and when N=2;

[0035] Fig.10 for Figure 7 The gain simulation result diagram of the circularly polarized antenna unit shown when N=2;

[0036] Fig.11 for Figure 7 The axial ratio simulation result diagram of the circularly polarized antenna unit shown when N=2;

[0037] Fig.12 for Figure 7 The circularly polarized antenna unit shown and the directional pattern simulation result diagram when N=2;

[0038] Fig.13 This is a schematic structural diagram of the circularly polarized antenna unit provided in Embodiment 1 and Embodiment 2 of the present invention when N=4;

[0039] Fig.14 for Fig.13 A top view of the circularly polarized antenna unit shown when N=4;

[0040] Fig.15 for Fig.13 The simulation result diagram of |S11| for the circularly polarized antenna unit shown and when N=4;

[0041] Fig.16 for Fig.13 The gain simulation result diagram of the circularly polarized antenna unit shown when N=4;

[0042] Fig.17 for Fig.13 The axial ratio simulation result diagram of the circularly polarized antenna unit shown when N=4;

[0043] Fig.18 for Fig.13 The circularly polarized antenna unit shown and the directional pattern simulation result diagram when N=4;

[0044] Description of reference numerals:

[0045] 1- dielectric layer, 2- feeding port, 3- radiator, 4- feeding transition piece, 41- transition lead-out portion, 42- transition connection portion, 5- coaxial line, 6- isolation cavity, 7- isolation layer. DETAILED DESCRIPTION

[0046] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc., indicating the orientation or positional relationship, are 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 limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0048] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0049] In addition, the technical features involved in the different embodiments of the present invention described below can be combined with each other as long as they do not conflict with each other.

[0050] Example 1

[0051] like Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig.13 and Fig.14 A circularly polarized antenna unit shown includes a first metal layer, a dielectric layer 1, a second metal layer, a feeding structure and an isolation structure, wherein the first metal layer and the second metal layer can be made of copper or other metal materials; the dielectric layer 1 is arranged below the first metal layer, specifically, the dielectric layer 1 can be ceramic or other materials with a relative dielectric constant of 5.9 or other materials; the second metal layer is arranged below the dielectric layer 1; the feeding structure includes a feeding port 2, a radiator 3, a plurality of feeding transition pieces 4 and a plurality of coaxial lines 5, the second metal layer is formed with a feeding port 2, the feeding port 2 and the feeding transition piece 4 are connected by the coaxial line 5, and the feeding transition piece 4 and the radiator 3 are connected by the coaxial line 5. It should be noted that since the thickness of the first metal layer and the second metal layer is relatively thin, it can be ignored relative to the dielectric layer 1, for this reason Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig.13 and Fig.14 The first metal layer and the second metal layer are not shown.

[0052] By providing a feeding transition piece 4, circular polarization is more easily achieved when the excitation current from the feeding port 2 reaches the radiator 3, and the effective radiation area is significantly increased, so that the circularly polarized antenna unit can achieve high gain and low axial ratio; and by providing an isolation structure, the isolation between the circularly polarized antenna units is effectively improved to achieve the expansion of the circularly polarized antenna units.

[0053] like Figure 1 and Figure 2 As shown, in this embodiment, one feed transition piece 4 is provided, two coaxial lines 5 are provided, the feed port 2 is connected to one end of the feed transition piece 4 through the coaxial line 5, and the other end of the feed transition piece 4 is connected to the radiator 3 through the coaxial line 5. As an alternative implementation, multiple feed transition pieces 4 may also be provided, and adjacent feed transition pieces 4 are connected through the coaxial line 5.

[0054] See Figure 1 and Figure 2The feed transition piece 4 includes a transition lead-out portion 41 and a transition connection portion 42, wherein one of the transition lead-out portions is connected to the feed port 2, and one of the transition connection portions is connected to the radiator 3. The transition connection portion 42 is an arc-shaped structure, which is protruding outward; the transition lead-out portion 41 is a linear structure. Of course, the transition lead-out portion 41 can also be a structure of other shapes, such as an arc-shaped structure. And as Figure 1 and Figure 2 As shown, the radiator 3 is a spiral structure, and the feed transition piece 4 and the radiator 3 are planar metal patches. The specific structural parameters of the radiator 3 can be set according to actual needs. For example, the spiral structure can appropriately adjust the radius change and the number of spiral turns according to the Archimedean spiral formula.

[0055] like Figure 1 and Figure 2 As shown, the isolation structure includes an isolation cavity 6 and an isolation layer 7, wherein the isolation cavity 6 is provided in the first metal layer, the dielectric layer 1, and the second metal layer, and the isolation layer 7 is provided on the cavity wall of the isolation cavity 6, and the isolation layer 7 is also provided on the upper wall surface of the first metal layer, wherein the isolation layer 7 can be formed by a metal patch or other means; and the isolation cavity 6 is filled with an isolation dielectric, and the radiator 3 is exposed to the isolation dielectric. It should be noted that since the thickness of the first metal layer and the second metal layer of the isolation layer 7 is relatively thin, it can be ignored relative to the dielectric layer 1, for this reason Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig.13 and Fig.14 The thickness of the isolation layer 7 is not shown and only a portion of the isolation layer 7 is shown; and the isolation medium is not shown in Figure 1 , Figure 2 , Figure 7 , Figure 8 , Fig.13 and Fig.14 As shown in FIG. 1 , specifically, the isolation medium may be ceramic or other materials with a relative dielectric constant of 5.9 or other materials.

[0056] Example 2

[0057] This embodiment provides a circularly polarized antenna, including several circularly polarized antenna units in Embodiment 1. The circularly polarized antenna units are arranged in an N×N array, where N is a natural number. Figure 1 and Figure 2 As shown, Figure 1 and Figure 2 N is 1 as shown in Figure 7 and Figure 8 As shown, Figure 7 and Figure 8N is 2, and the radiator 3 of each circularly polarized antenna unit is rotated counterclockwise by 90 degrees in sequence to change the interval between the radiators 3 and increase the isolation of each circularly polarized antenna unit; and Fig.13 and Fig.14 As shown, Fig.13 and Fig.14 The N shown in FIG. is 4. When the overall structure is in a regular shape such as a rectangular parallelepiped, it is convenient to arrange the circularly polarized antenna units, thereby realizing an antenna array with more units.

[0058] The following is a further explanation of the technical effect of the circularly polarized antenna in combination with simulation experiments:

[0059] 1. Simulation experiment conditions:

[0060] The software platform for the simulation experiment of the present invention is: HFSS19.09 (high frequency structure simulation).

[0061] 2. Simulation content and results analysis:

[0062] Simulation 1, the parameters such as |S11|, gain, axial ratio and radiation pattern of the circularly polarized antenna unit with N=1 in the frequency band from 19GHz to 22GHz are simulated. The results are as follows Figures 3 to 6 The antenna impedance bandwidth is from 19GHz to 21.3GHz, the antenna gain can reach 8.9dB, and the fluctuation of the gain amplitude is less than 1dB, indicating that the feed port is well matched in this frequency band; within the working frequency band of the antenna, the axial ratio of the antenna is less than 3dB slot. Thus, the high gain and low axial ratio performance requirements are achieved.

[0063] Simulation 2 simulates the parameters of |S11|, gain, axial ratio and radiation pattern of N=2 circularly polarized antenna units in the frequency band from 19GHz to 22GHz. The results are as follows Figures 9 to 12 The antenna impedance bandwidth is from 19GHz to 21.8GHz, the antenna gain can reach 12.6dB, and the gain amplitude fluctuation is less than 1dB, indicating that the feed port is well matched within this frequency band; within the antenna's operating frequency band, the antenna's axial ratio is less than 0.4dB. This achieves the high gain and low axial ratio performance requirements, and the performance parameters are significantly optimized.

[0064] Simulation 3 simulates the parameters of |S11|, gain, axial ratio and radiation pattern of N=4 circularly polarized antenna units in the frequency band from 19GHz to 22GHz. The results are as follows Figures 15 to 18The antenna impedance bandwidth is 19GHz to 22GHz, the antenna gain can reach 12.6dB, and the gain amplitude fluctuation is less than 1dB, indicating that the feed port is well matched within this frequency band; within the antenna's operating frequency band, the antenna's axial ratio is less than 0.9dB. This achieves the high gain and low axial ratio performance requirements, and at the same time shows that the invention can achieve high-performance planar spiral circularly polarized array antennas. It should be noted that in Figures 3 to 6 , Figures 9 to 12 , Figures 15 to 18 In the figure, Phi is Φ, Theta is θ, LHCP is left-hand circular polarization, RHCP is right-hand circular polarization, |S11| is return loss, Freq is frequency, Gain is gain, AR is axial ratio, deg is angle, and gain total is total gain.

[0065] Obviously, the above embodiments are merely examples for the purpose of clear explanation, and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived therefrom are still within the scope of protection of the invention.

Claims

1. A circularly polarized antenna unit, characterized in that: include: A first metal layer; a dielectric layer, disposed below the first metal layer; A second metal layer, which is disposed below the dielectric layer; A feeding structure, comprising a feeding port, a radiator, a plurality of feeding transition pieces and a plurality of coaxial lines, wherein the second metal layer is formed with the feeding port, the feeding port and the feeding transition piece are connected through the coaxial line, the feeding transition piece and the radiator are connected through the coaxial line, and adjacent feeding transition pieces are connected through the coaxial line; The feed transition piece is provided with one, the coaxial line is provided with two, the feed port and one end of the feed transition piece are connected through the coaxial line, and the other end of the feed transition piece and the radiator are connected through the coaxial line; The feed transition piece includes a transition lead-out portion and a transition connection portion, wherein one of the transition lead-out portions is connected to the feed port, and one of the transition connection portions is connected to the radiator, the transition connection portion is an arc-shaped structure, and the arc-shaped structure is protruding outward; the transition lead-out portion is a linear structure.

2. A circularly polarized antenna unit according to claim 1, characterized in that: The feed transition piece and the radiator are planar metal patches.

3. A circularly polarized antenna unit according to claim 1 or 2, characterized in that: It also includes an isolation structure, which includes an isolation cavity and an isolation layer, wherein the first metal layer, the dielectric layer and the second metal layer are provided with an isolation cavity, and the isolation layer is provided on the cavity wall of the isolation cavity, wherein the isolation cavity is filled with an isolation medium, and the radiator is exposed from the isolation medium.

4. A circularly polarized antenna unit according to claim 3, characterized in that: The isolation layer is also arranged on the upper wall surface of the first metal layer.

5. A circularly polarized antenna, characterized in that: The invention comprises the circularly polarized antenna units as claimed in any one of claims 1 to 4.

6. A circularly polarized antenna according to claim 5, characterized in that: The circularly polarized antenna units are arranged in an N×N array, where N is a natural number.

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