Circularly polarized unit antenna and ternary circularly polarized microstrip array antenna

Abstract

The invention discloses a circularly polarized unit antenna and a ternary circularly polarized microstrip array antenna, and relates to the technical field of circularly polarized antennas. Each unit antenna comprises a first dielectric substrate, a first copper patch, a second dielectric substrate, a second copper patch, a covering insulating plate and a feed part, the first dielectric substrate is not grounded, the second dielectric substrate is grounded, the first copper patch is attached to the top surface of the first dielectric substrate, the second dielectric substrate is arranged right below the first dielectric substrate at an interval, and the covering insulating plate is arranged on the top surface of the second dielectric substrate. The second copper patch is attached to the top surface of the second dielectric substrate and is arranged right below the first copper patch at an interval, the covering insulating plate covers the first copper patch, and the feed piece penetrates through the second dielectric substrate from bottom to top and is electrically connected with the second copper patch, so that two resonance points can be provided through the upper copper patch and the lower copper patch; and the two resonance points are adjusted to be close to each other, so that the purpose of widening the bandwidth of the antenna is achieved, the miniaturization of the product is facilitated, and the practical application and popularization are facilitated.

Description

Technical Field

[0001] The invention belongs to the technical field of circularly polarized antennas, and in particular relates to a circularly polarized unit antenna and a three-element circularly polarized microstrip array antenna. Background Art

[0002] When electromagnetic waves propagate in space, the direction of their electric field changes in a certain direction, and this change is the polarization of the electromagnetic wave. According to the polarization mode of electromagnetic waves, electromagnetic waves can be divided into linearly polarized waves, elliptically polarized waves and circularly polarized waves, that is, electromagnetic waves whose electric field direction changes in a plane are called linearly polarized waves, electromagnetic waves whose electric field direction changes in rotation are called elliptically polarized waves, and electromagnetic waves whose electric field direction changes in rotation and whose electric field amplitude remains unchanged are called circularly polarized waves. Looking at the propagation direction of the electromagnetic wave, if the rotation direction of the circularly polarized wave is clockwise, then the circularly polarized wave is called a right-hand circularly polarized wave, and if the rotation direction of the circularly polarized wave is counterclockwise, then the circularly polarized wave is called a left-hand circularly polarized wave.

[0003] A circularly polarized antenna is an antenna used to receive and transmit circularly polarized waves. Right-hand circularly polarized waves need to be transmitted and received by a right-hand circularly polarized antenna, while left-hand circularly polarized waves need to be transmitted and received by a left-hand circularly polarized antenna, otherwise polarization loss will occur, also known as polarization isolation. But an interesting phenomenon is that a circularly polarized antenna can receive any form of linearly polarized waves, and the electromagnetic waves it radiates can also be received by any form of linearly polarized antenna. It is precisely because of this feature that the transmitting antenna and the receiving antenna can be more flexible, that is, in satellite communication systems, circularly polarized antennas are indispensable key components.

[0004] In actual implementation, circularly polarized antennas are usually large in size, high in profile, relatively bulky and difficult to assemble. In particular, for circularly polarized antennas for satellite communications, most are reflective antennas, the antennas are very thick, and the antennas all operate in a single frequency band, so that when used for communications or radar, the operating bandwidth is relatively narrow. Due to the integration of multiple frequency bands in applications such as communications or radar, and the need for wideband circularly polarized phased arrays such as synthetic aperture radar or electronic countermeasures, as well as the thin thickness requirements for RCS (Radar Cross Section) in many scenarios, ultra-wideband thin circularly polarized antennas have a large application space. However, in the C band (i.e., the radio wave band with a frequency of 4 to 8 GHz) and the Ku band (i.e., the radio wave band with a frequency of 12 to 18 GHz), due to the relatively large size of the antenna, it is relatively difficult to achieve ultra-wideband and thin thickness. Summary of the invention

[0005] The object of the present invention is to provide a circularly polarized unit antenna and a three-element circularly polarized microstrip array antenna, so as to solve the problem that it is difficult to expand the bandwidth of the circularly polarized antenna due to the relatively large antenna size.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In a first aspect, a circularly polarized unit antenna is provided, comprising a first dielectric substrate, a first copper patch, a second dielectric substrate, a second copper patch, a covering insulating plate and a feeding element, wherein the first dielectric substrate is not grounded and the second dielectric substrate is grounded;

[0008] The first copper patch is attached to the top surface of the first dielectric substrate, the second dielectric substrate is spaced just below the first dielectric substrate, the second copper patch is attached to the top surface of the second dielectric substrate and spaced just below the first copper patch, and the covering insulating plate covers the first copper patch;

[0009] The feeding element passes through the second dielectric substrate from bottom to top and is electrically connected to the second copper patch.

[0010] Based on the above invention content, a new circularly polarized antenna structure for achieving bandwidth expansion and product miniaturization is provided, namely, comprising a first dielectric substrate, a first copper patch, a second dielectric substrate, a second copper patch, a covering insulating plate and a feeding element, wherein the first dielectric substrate is not grounded, the second dielectric substrate is grounded, the first copper patch is attached to the top surface of the first dielectric substrate, the second dielectric substrate is arranged at intervals directly below the first dielectric substrate, the second copper patch is attached to the top surface of the second dielectric substrate and is arranged at intervals directly below the first copper patch, the covering insulating plate covers the first copper patch, and the feeding element passes through the second dielectric substrate from bottom to top and is electrically connected to the second copper patch, so that two resonance points can be provided by the upper and lower copper patches, and the two resonance points are adjusted to be close to each other, thereby achieving the purpose of widening the antenna bandwidth, and at the same time, it is conducive to product miniaturization and convenient for practical application and promotion.

[0011] In a possible design, it also includes a ring-shaped insulator, a first metal foil and a second metal foil, wherein the first metal foil is attached to the inner wall surface of the ring-shaped insulator, and the second metal foil is attached to the outer wall surface of the ring-shaped insulator;

[0012] The annular insulator is disposed between the first dielectric substrate and the second dielectric substrate, and the top annular opening of the annular insulator is in contact with the bottom surface of the first dielectric substrate, and the bottom annular opening of the annular insulator is in contact with the top surface of the second dielectric substrate;

[0013] The annular opening at the bottom end of the annular insulator surrounds the second metal patch at intervals.

[0014] In a possible design, the space surrounded by the first dielectric substrate, the second dielectric substrate and the annular insulator is filled with air or a high dielectric constant medium.

[0015] In a possible design, a plurality of insulating screws are further included, and a plurality of first threaded through holes corresponding to the plurality of insulating screws are opened on the first dielectric substrate, and a plurality of second threaded through holes corresponding to the plurality of insulating screws and the plurality of first threaded through holes are opened on the second dielectric substrate, and the second threaded through holes are located directly below the corresponding first threaded through holes;

[0016] The first dielectric substrate and the second dielectric substrate are spaced apart from each other by the insulating screws that pass through the corresponding first threaded through holes and the second threaded through holes in sequence.

[0017] In a possible design, the insulating screw is made of rubber.

[0018] In a possible design, the feeding element adopts a coaxial line.

[0019] In one possible design, when the second metal patch adopts a circular patch with a radius of r2, the feeding point is located on the diameter line of the circular patch and the distance from the feeding point to the nearest end point of the diameter line is η×r2, wherein the feeding point refers to the electrical connection point between the coaxial line and the second metal patch, and η represents a positive number less than or equal to 0.1.

[0020] In a second aspect, a three-element circularly polarized microstrip array antenna is provided, comprising a first dielectric substrate, three first copper patches, a second dielectric substrate, three second copper patches and a feeding element, wherein the first dielectric substrate is not grounded, the second dielectric substrate is grounded, and the three second copper patches correspond one to one to the three first copper patches;

[0021] The three first copper patches are attached to the top surface of the first dielectric substrate at equal intervals in the annular direction, the second dielectric substrate is arranged directly below the first dielectric substrate at intervals, and the three second copper patches are attached to the top surface of the second dielectric substrate at equal intervals in the annular direction, and the second copper patches are arranged directly below the corresponding first copper patches at intervals;

[0022] The feeding device adopts a one-to-three equal-division power distributor with a rotating feeding network structure, and the three output ends of the one-to-three equal-division power distributor correspond one-to-one to the three second copper patches, and each of the three output ends passes through the second dielectric substrate from bottom to top and is electrically connected to the corresponding second copper patch.

[0023] In a possible design, three annular insulators corresponding to the three second copper patches are further included, wherein the first metal foil is attached to the inner wall surface of the annular insulator, and the second metal foil is attached to the outer wall surface of the annular insulator;

[0024] The annular insulator is disposed between the first dielectric substrate and the second dielectric substrate, and the top annular opening of the annular insulator is in contact with the bottom surface of the first dielectric substrate, and the bottom annular opening of the annular insulator is in contact with the top surface of the second dielectric substrate;

[0025] The annular opening at the bottom end of the annular insulator surrounds the corresponding second copper patch at intervals.

[0026] In a possible design, the annular insulator is made of rubber.

[0027] In a possible design, the annular insulator adopts a square annular structure, a circular annular structure or a regular polygonal annular structure.

[0028] In a possible design, the space surrounded by the first dielectric substrate, the second dielectric substrate and the annular insulator is filled with air or a high dielectric constant medium.

[0029] In a possible design, the first metal foil or the second metal foil is aluminum foil.

[0030] In a possible design, the first dielectric substrate or the second dielectric substrate is made of FR-4 grade material.

[0031] In a possible design, the second dielectric substrate is grounded via a metal layer attached to the bottom surface of the second dielectric substrate.

[0032] Beneficial effects of the above scheme:

[0033] (1) The present invention provides a novel circularly polarized antenna structure for achieving bandwidth expansion and product miniaturization, namely, comprising a first dielectric substrate, a first copper patch, a second dielectric substrate, a second copper patch, a covering insulating plate and a feeding element, wherein the first dielectric substrate is not grounded, the second dielectric substrate is grounded, the first copper patch is attached to the top surface of the first dielectric substrate, the second dielectric substrate is arranged at intervals directly below the first dielectric substrate, the second copper patch is attached to the top surface of the second dielectric substrate and is arranged at intervals directly below the first copper patch, the covering insulating plate covers the first copper patch, and the feeding element passes through the second dielectric substrate from bottom to top and is electrically connected to the second copper patch, so that two resonance points can be provided by the upper and lower copper patches, and the two resonance points are adjusted to be close to each other, thereby achieving the purpose of widening the antenna bandwidth, and at the same time facilitating product miniaturization, and facilitating practical application and promotion;

[0034] (2) By configuring a ring-shaped insulator between the upper and lower substrates, the gain can be effectively improved without affecting other performance parameters;

[0035] (3) A new three-element circularly polarized microstrip array antenna structure is also provided to achieve bandwidth expansion and product miniaturization, which can achieve the purpose of widening the bandwidth of the three-element circularly polarized microstrip array antenna, while being conducive to product miniaturization, and can also effectively improve the gain without affecting other performance parameters, thereby facilitating practical application and promotion. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0037] Figure 1 This is a schematic diagram of the oblique top view structure of a circularly polarized unit antenna provided in an embodiment of the present invention.

[0038] Figure 2 A left side structural schematic diagram of a circularly polarized unit antenna provided in an embodiment of the present invention.

[0039] Figure 3 A schematic diagram of the oblique upward structure of a circularly polarized unit antenna provided in an embodiment of the present invention.

[0040] Figure 4 A schematic diagram of the positional relationship between the feeding point and the lower metal patch provided in an embodiment of the present invention.

[0041] Figure 5 A schematic diagram of the oblique top view structure of a three-element circularly polarized microstrip array antenna provided in an embodiment of the present invention.

[0042] Figure 6 A schematic diagram of the upward structure of a three-element circularly polarized microstrip array antenna provided in an embodiment of the present invention.

[0043] In the above drawings: 10 - upper dielectric substrate; 11 - upper metal patch; 20 - lower dielectric substrate; 21 - lower metal patch; 60 - covering insulating plate; 40 - feeding element; 41 - output end; 50 - ring insulator; 60 - insulating screw. DETAILED DESCRIPTION

[0044] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the present invention will be briefly introduced below in combination with the drawings and the description of the embodiments or the prior art. Obviously, the following description of the structures of the drawings is only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these embodiments without creative work. It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention.

[0045] It should be understood that although the terms first and second, etc. may be used herein to describe various objects, these objects should not be limited by these terms. These terms are only used to distinguish one object from another object. For example, a first object can be referred to as a second object, and similarly, a second object can be referred to as a first object without departing from the scope of the exemplary embodiments of the present invention.

[0046] It should be understood that the term "and / or" that may appear in this document is merely a description of the association relationship between associated objects, indicating that there may be three relationships. For example, A and / or B can indicate three situations: A exists alone, B exists alone, or A and B exist at the same time. For another example, A, B and / or C can indicate the existence of any one of A, B and C or any combination of them. The term " / and" that may appear in this document describes another type of association object relationship, indicating that there may be two relationships. For example, A / and B can indicate two situations: A exists alone or A and B exist at the same time. In addition, the character " / " that may appear in this document generally indicates that the previous and next associated objects are in an "or" relationship.

[0047] Embodiment 1

[0048] like Figures 1 to 4 As shown, the circularly polarized unit antenna provided in this embodiment includes but is not limited to a first dielectric substrate 10, a first copper patch 11, a second dielectric substrate 20, a second copper patch 21, a covering insulating plate 30 and a feeding element 40, wherein the first dielectric substrate 10 is not grounded, and the second dielectric substrate 20 is grounded; the first copper patch 11 is attached to the top surface of the first dielectric substrate 10, the second dielectric substrate 20 is arranged at intervals directly below the first dielectric substrate 10, the second copper patch 21 is attached to the top surface of the second dielectric substrate 20 and is arranged at intervals directly below the first copper patch 11, and the covering insulating plate 30 covers the first copper patch 11; the feeding element 40 passes through the second dielectric substrate 20 from bottom to top and is electrically connected to the second copper patch 21.

[0049] like Figures 1 to 3As shown, in the specific structure of the circularly polarized unit antenna, the first dielectric substrate 10 is used to carry the first copper patch 11, the covering insulating plate 30 and other components, which can be but not limited to be made of FR-4 grade material (its relative dielectric constant is 4.7, and the tangent loss is 0.03). The first copper patch 11 is used as a parasitic patch relative to the main radiation patch to add a new resonance point, which can be but not limited to being implemented by a circular copper patch. The second dielectric substrate 20 is used to carry the second copper patch 21 and other components, which can also be but not limited to being made of FR-4 grade material, and its size needs to be slightly larger than the first dielectric substrate 10. The second copper patch 21 is used as the main radiation patch to provide an originally required resonance point, which can also be but not limited to being implemented by a circular copper patch, and its size needs to be slightly larger than the first copper patch 11. The covering insulating plate 30 is used to optimize the measurement result of the parameter S(1,1), which can be but not limited to being made of plastic material, and its thickness and size can be specifically obtained through simulation optimization. The feeder 40 is used to feed the main radiation patch, which can be implemented by, but not limited to, a coaxial line. In addition, the first dielectric substrate 10 is not grounded, and the second dielectric substrate 20 is grounded, which can effectively improve the antenna performance, and in order to increase the size of the ground wire, preferably, the second dielectric substrate 20 is grounded through a metal layer attached to the bottom surface of the second dielectric substrate 20, and the aforementioned metal layer can be specifically, but not limited to, a copper layer.

[0050] Since the first copper patch 11 and the second copper patch 21 each provide a resonance point, a resonance point can be found according to the antenna operating frequency, and the newly added resonance point is made a high-frequency resonance point relative to the resonance point, and the originally required resonance point is made a low-frequency resonance point relative to the resonance point, and then the radius r1 of the first copper patch 11 and the radius r2 of the second copper patch 21 are adjusted to make the two resonance points close to each other, so as to achieve the purpose of widening the antenna bandwidth. The specific adjustment process of the above-mentioned radius can firstly calculate the initial radius of the second copper patch 21 according to the antenna operating frequency, substrate thickness and substrate relative dielectric constant, and then adjust the radius of the first copper patch 11 near the initial radius, and finally obtain the final radius of the first copper patch 11 and the second copper patch 21 through simulation optimization. In addition, the first copper patch 11 and the second copper patch 21 are equivalent to forming a capacitor, and the spacing between the first dielectric substrate 10 and the second dielectric substrate 20 can be determined through simulation optimization.

[0051] Preferably, it also includes an annular insulator 50, a first metal foil and a second metal foil, wherein the first metal foil is attached to the inner wall surface of the annular insulator 50, and the second metal foil is attached to the outer wall surface of the annular insulator 50; the annular insulator 50 is arranged between the first dielectric substrate 10 and the second dielectric substrate 20, and the top annular opening of the annular insulator 50 is in contact with the bottom surface of the first dielectric substrate 10, and the bottom annular opening of the annular insulator 50 is in contact with the top surface of the second dielectric substrate 20; the bottom annular opening of the annular insulator 50 surrounds the second copper patch 21 at intervals. Figures 1-2 As shown, the annular insulator 50 is used to form a frame between the first dielectric substrate 10 and the second dielectric substrate 20, which can effectively improve the gain without affecting other performance parameters. Specifically, the annular insulator 50 can be made of, but not limited to, rubber material; the annular insulator 50 can be, but not limited to, a square annular structure, a circular annular structure, or a regular polygonal annular structure, etc. ( Figures 1-2 The first metal foil or the second metal foil may be, but is not limited to, aluminum foil. In addition, the space surrounded by the first dielectric substrate 10, the second dielectric substrate 20 and the annular insulator 50 is filled with air or a high dielectric constant medium (which is defined relative to the gate dielectric material SiO2, and is generally referred to as a high dielectric constant medium as long as the dielectric constant is greater than the dielectric constant of SiO2, which is 3.9), which can further facilitate miniaturization (i.e., the higher the relative dielectric constant, the shorter the wavelength in the medium, the smaller the required size, and thus can facilitate miniaturization).

[0052] Preferably, it further comprises a plurality of insulating screws 60, and a plurality of first threaded through holes corresponding to the plurality of insulating screws 60 are opened on the first dielectric substrate 10, and a plurality of second threaded through holes corresponding to the plurality of insulating screws 60 and the plurality of first threaded through holes are opened on the second dielectric substrate 20, and the second threaded through holes are located directly below the corresponding first threaded through holes; the first dielectric substrate 10 and the second dielectric substrate 20 control the substrate spacing by the insulating screws 60 passing through the corresponding first threaded through holes and the second threaded through holes in sequence. Figures 1-2 As shown, there are four insulating screws 60, which not only play a role in fixing the upper and lower substrates, but also play a role in controlling the distance between the upper and lower substrates. In addition, the insulating screws 60 can be made of rubber material but are not limited to it.

[0053] Preferably, when the second copper patch 21 is a circular patch with a radius of r2, the feeding point is located on the diameter line of the circular patch and the distance from the feeding point to the nearest end point of the diameter line is η×r2, wherein the feeding point refers to the electrical connection point between the coaxial line and the second copper patch 21, and η represents a positive number less than or equal to 0.1. In this way, the feeding point can be adjusted to a position close to the edge of the patch, thereby making the entire path of the current flowing through the patch longer, the electrical size larger, and the physical size smaller, which is further conducive to miniaturization. Figure 4 As shown, the feeding point is represented by P, the nearest end point of the diameter line is represented by A, and the farthest end point of the diameter line is represented by B. By adjusting the position of the feeding point P, the length values ​​of the line segments PA and PB can be changed to achieve 50 ohm impedance matching and antenna miniaturization. For example, if the radius r2 of the circular patch is 10.6 mm, after simulation optimization, the length of the line segment PA is 0.6 mm, and the length of the line segment PB is 20.6 mm, that is, the value of η is 0.0566.

[0054] In summary, the circularly polarized unit antenna provided in this embodiment has the following technical effects:

[0055] (1) This embodiment provides a novel circularly polarized antenna structure for achieving bandwidth expansion and product miniaturization, namely, comprising a first dielectric substrate, a first copper patch, a second dielectric substrate, a second copper patch, a covering insulating plate and a feeding element, wherein the first dielectric substrate is not grounded, the second dielectric substrate is grounded, the first copper patch is attached to the top surface of the first dielectric substrate, the second dielectric substrate is arranged at intervals directly below the first dielectric substrate, the second copper patch is attached to the top surface of the second dielectric substrate and is arranged at intervals directly below the first copper patch, the covering insulating plate covers the first copper patch, and the feeding element passes through the second dielectric substrate from bottom to top and is electrically connected to the second copper patch, so that two resonance points can be provided by the upper and lower copper patches, and the two resonance points are adjusted to be close to each other, thereby achieving the purpose of widening the antenna bandwidth, and at the same time facilitating product miniaturization, and facilitating practical application and promotion;

[0056] (2) By configuring a ring-shaped insulator between the upper and lower substrates, the gain can be effectively improved without affecting other performance parameters.

[0057] Embodiment 2

[0058] Based on the technical solution of the first embodiment, this embodiment further provides a three-element circularly polarized microstrip array antenna, including but not limited to a first dielectric substrate 10, three first copper patches 11, a second dielectric substrate 20, three second copper patches 21 and a feeding element 40, wherein the first dielectric substrate 10 is not grounded, the second dielectric substrate 20 is grounded, the three second copper patches 21 correspond to the three first copper patches 11 one by one; the three first copper patches 11 are attached to the top surface of the first dielectric substrate 10 at equal intervals in the annular direction, and the second dielectric substrate 20 is arranged at intervals on the first dielectric substrate 10. The three second copper patches 21 are circumferentially and evenly attached to the top surface of the second dielectric substrate 20, and the second copper patches 21 are spaced apart and arranged directly below the corresponding first copper patches 11; the feeding element 40 adopts a one-to-three equal-division power divider with a rotating feeding network structure, and the three output ends 41 of the one-to-three equal-division power divider correspond to the three second copper patches 21 one by one, and each of the three output ends 41 passes through the second dielectric substrate 20 from bottom to top and is electrically connected to the corresponding second copper patch 21.

[0059] like Figures 5-6 As shown, in the specific structure of the three-element circularly polarized microstrip array antenna, the circumferential phase difference between any two first copper patches 11 is 120 degrees, and the circumferential phase difference between any two second copper patches 21 is 120 degrees. The specific technical details of the first dielectric substrate 10, the first copper patch 11, the dielectric substrate 20 and the second copper patch 21 can be derived with reference to Example 1, and will not be repeated here. The one-to-three equal power divider is used to feed the three second copper patches 21 with equal power and provide a certain phase difference (for example, 120 degrees). In this way, through the aforementioned specific structure, the purpose of widening the bandwidth of the three-element circularly polarized microstrip array antenna can also be achieved, while being conducive to product miniaturization, and convenient for practical application and promotion.

[0060] Preferably, three annular insulators 50 corresponding to the three second copper patches 21 are further included, wherein the first metal foil is attached to the inner wall surface of the annular insulator 50, and the second metal foil is attached to the outer wall surface of the annular insulator 50; the annular insulator 50 is arranged between the first dielectric substrate 10 and the second dielectric substrate 20, and the top annular opening of the annular insulator 50 is in contact with the bottom surface of the first dielectric substrate 10, and the bottom annular opening of the annular insulator 50 is in contact with the top surface of the second dielectric substrate 20; the bottom annular opening of the annular insulator 50 surrounds the corresponding second copper patches 21 at intervals. Figure 5As shown, the three annular insulators 50 are arranged at equal intervals in the annular direction, and three frames are formed between the first dielectric substrate 10 and the second dielectric substrate 20, which can effectively improve the gain without affecting other performance parameters. Specifically, the annular insulator 50 can be made of, but not limited to, rubber material; the annular insulator 50 can be made of, but not limited to, a square annular structure, a circular annular structure, or a regular polygonal annular structure, etc. ( Figure 5 The first metal foil or the second metal foil may be, but is not limited to, aluminum foil. In addition, the space surrounded by the first dielectric substrate 10, the second dielectric substrate 20, and the annular insulator 50 is filled with air or a high dielectric constant medium, which can further facilitate miniaturization (i.e., the higher the relative dielectric constant, the shorter the wavelength in the medium, the smaller the required size, and thus can facilitate miniaturization).

[0061] Preferably, the first dielectric substrate 10 or the second dielectric substrate 20 is made of FR-4 grade material.

[0062] Preferably, the second dielectric substrate 20 is grounded via a metal layer attached to the bottom surface of the second dielectric substrate 20 .

[0063] In summary, the three-element circularly polarized microstrip array antenna provided in this embodiment has the following technical effects:

[0064] (1) This embodiment provides a novel three-element circularly polarized microstrip array antenna structure that achieves bandwidth expansion and product miniaturization, which can achieve the purpose of widening the bandwidth of the three-element circularly polarized microstrip array antenna, while being conducive to product miniaturization, and can also effectively improve the gain without affecting other performance parameters, thereby facilitating practical application and promotion.

[0065] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the protection scope of the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A circularly polarized unit antenna, characterized in that: The invention comprises a first dielectric substrate (10), a first copper patch (11), a second dielectric substrate (20), a second copper patch (21), a covering insulating plate (30) and a feeding element (40), wherein the first dielectric substrate (10) is not grounded and the second dielectric substrate (20) is grounded; The first copper patch (11) is attached to the top surface of the first dielectric substrate (10), the second dielectric substrate (20) is arranged at a distance directly below the first dielectric substrate (10), the second copper patch (21) is attached to the top surface of the second dielectric substrate (20) and is arranged at a distance directly below the first copper patch (11), and the covering insulating plate (30) covers the first copper patch (11); The feeding element (40) passes through the second dielectric substrate (20) from bottom to top and is electrically connected to the second copper patch (21).

2. The circularly polarized unit antenna according to claim 1, characterized in that: It also includes a plurality of insulating screws (60), and a plurality of first threaded through holes corresponding one-to-one to the plurality of insulating screws (60) are opened on the first dielectric substrate (10), and a plurality of second threaded through holes corresponding one-to-one to the plurality of insulating screws (60) and the plurality of first threaded through holes are opened on the second dielectric substrate (20), and the second threaded through holes are located directly below the corresponding first threaded through holes; The first dielectric substrate (10) and the second dielectric substrate (20) are spaced apart by the insulating screws (60) that pass through the corresponding first threaded through holes and the second threaded through holes in sequence.

3. A three-element circularly polarized microstrip array antenna, characterized in that: The invention comprises a first dielectric substrate (10), three first copper patches (11), a second dielectric substrate (20), three second copper patches (21) and a feeding element (40), wherein the first dielectric substrate (10) is not grounded, the second dielectric substrate (20) is grounded, and the three second copper patches (21) correspond one to one to the three first copper patches (11); The three first copper patches (11) are attached to the top surface of the first dielectric substrate (10) at equal intervals in the annular direction, the second dielectric substrate (20) is arranged at intervals directly below the first dielectric substrate (10), and the three second copper patches (21) are attached to the top surface of the second dielectric substrate (20) at equal intervals in the annular direction, and the second copper patches (21) are arranged at intervals directly below the corresponding first copper patches (11); The feeding element (40) adopts a one-to-three equal-division power distributor in a rotating feeding network structure, and the three output ends (41) of the one-to-three equal-division power distributor correspond to the three second copper patches (21) one by one, and each of the three output ends (41) passes through the second dielectric substrate (20) from bottom to top and is electrically connected to the corresponding second copper patch (21).

4. The three-element circularly polarized microstrip array antenna according to claim 3, characterized in that: It also includes three annular insulators (50) corresponding one to the three second copper patches (21), wherein a first metal foil is attached to the inner wall surface of the annular insulator (50), and a second metal foil is attached to the outer wall surface of the annular insulator (50); The annular insulator (50) is arranged between the first dielectric substrate (10) and the second dielectric substrate (20), and the top annular opening of the annular insulator (50) is in contact with the bottom surface of the first dielectric substrate (10), and the bottom annular opening of the annular insulator (50) is in contact with the top surface of the second dielectric substrate (20); The annular opening at the bottom end of the annular insulator (50) surrounds the corresponding second copper patch (21) at intervals.

5. The three-element circularly polarized microstrip array antenna according to claim 4, characterized in that: The annular insulator (50) is made of rubber material.

6. The three-element circularly polarized microstrip array antenna according to claim 4, characterized in that: The annular insulator (50) adopts a square annular structure, a circular annular structure or a regular polygonal annular structure.

7. The three-element circularly polarized microstrip array antenna according to claim 4, characterized in that: The space surrounded by the first dielectric substrate (10), the second dielectric substrate (20) and the annular insulator (50) is filled with air or a high dielectric constant medium.

8. The three-element circularly polarized microstrip array antenna according to claim 4, characterized in that: The first metal foil or the second metal foil is aluminum foil.

9. The three-element circularly polarized microstrip array antenna according to claim 3, characterized in that: The first dielectric substrate (10) or the second dielectric substrate (20) is made of FR-4 grade material.

10. The three-element circularly polarized microstrip array antenna according to claim 3, characterized in that: The second dielectric substrate (20) is grounded via a metal layer attached to the bottom surface of the second dielectric substrate (20).

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