A broadband low-profile circularly polarized dielectric resonator antenna

Abstract

The application discloses a broadband low-profile circularly polarized dielectric resonator antenna, which comprises a first dielectric substrate with a microstrip slot coupling feeding unit and a dielectric resonator arranged on the first dielectric substrate; four corner blocks are arranged on the dielectric resonator respectively, and each corner block is symmetrically arranged with the center of the dielectric resonator as a symmetric center; a second dielectric substrate is arranged on each corner block of the dielectric resonator, and a parasitic metal strip is arranged between each second dielectric substrate and the dielectric resonator. The application combines the feeding coupling slot mode with the basic mode and the third high-order mode of the dielectric resonator, effectively widens the impedance and axial ratio bandwidth, and selects the alumina ceramic material without surface loss and the resonator structure, thereby significantly improving the gain, reducing the profile height of the antenna and improving the radiation efficiency of the antenna.

Description

Technical Field

[0001] This invention relates to the field of antenna technology, and more specifically to a wideband, low-profile, circularly polarized dielectric resonator antenna. Background Technology

[0002] Since the beginning of the 21st century, with the rapid development of wireless communication technology and the dramatic increase in data processing demands, communication systems are gradually shifting towards antenna solutions that use higher frequency bands, wider spectrum, are more stable and reliable, and are easier to integrate. This trend aims to meet the growing demand of modern society for high-speed, high-capacity, and low-latency communication.

[0003] To address the multiple challenges in modern communication systems, broadband circularly polarized antennas have been widely used in satellite communications, navigation systems, and mobile communications due to their strong anti-multipath interference capabilities, avoidance of polarization mismatch loss, and support for multi-band communications, which has driven their rapid development.

[0004] However, the performance of traditional metal patch broadband circularly polarized antennas is limited at high frequencies due to increased metal losses. In contrast, dielectric resonator antennas (DRAs), as an emerging antenna technology, exhibit excellent high-frequency performance due to their extremely low conductor losses and surface wave suppression characteristics, thus becoming a focus of current research and gradually gaining widespread acceptance. In 2020, Liu et al. successfully achieved a 52% impedance bandwidth by providing equal-amplitude and orthogonal phase signals through a sequential feed network and feeding a cylindrical DRA using coupling slots, but this introduced a complex feed structure, increasing the difficulty of design and manufacturing. In 2022, Tong et al. proposed a method to introduce a third higher-order mode into the band without increasing the volume of the dielectric resonator by adding high-dielectric-constant BaTiO3 particles at specific locations, thereby achieving a 25.4% overlap between the axial ratio bandwidth and the impedance bandwidth. However, the fabrication process for this method is relatively complex. In 2023, Chen et al. excited patch mode by inserting distributed patches inside the DRA, achieving an impedance bandwidth of 38.9%. However, its 0.14-wavelength profile height limited the antenna's miniaturization advantages.

[0005] In summary, although broadband circularly polarized dielectric resonator antennas have shown broad application prospects in modern wireless communication systems, especially in dealing with high frequency bands, large bandwidth and low loss, there are still many problems that need to be solved. Summary of the Invention

[0006] The present invention aims to at least partially solve one of the technical problems existing in the related art.

[0007] The purpose of this invention is to provide a wideband, low-profile, circularly polarized dielectric resonator antenna that avoids the use of complex feed networks while effectively expanding the bandwidth and improving gain and efficiency.

[0008] To achieve the above objectives, the present invention provides a wideband, low-profile, circularly polarized dielectric resonator antenna, characterized in that it comprises:

[0009] A first dielectric substrate having a microstrip gap coupled feed unit;

[0010] And a dielectric resonator arranged on a first dielectric substrate, wherein each of the four corners of the dielectric resonator has a corner block, and each corner block is arranged symmetrically with the center of the dielectric resonator as the center of symmetry;

[0011] Each corner block of the dielectric resonator is provided with a second dielectric substrate, and a parasitic metal strip is provided between each second dielectric substrate and the dielectric resonator; the parasitic metal strip is printed on the surface of the second dielectric substrate facing the dielectric resonator.

[0012] A further preferred embodiment of the present invention is that the microstrip slot-coupled feed unit comprises:

[0013] A metal ground plane etched on the side surface of the first dielectric substrate facing the dielectric resonator; and a feed microstrip line attached to the side surface of the first dielectric substrate facing away from the dielectric resonator.

[0014] The metal ground plane is etched with vertically intersecting air gaps, and the dielectric resonator is located above these vertically intersecting air gaps.

[0015] Preferably, the vertically intersecting air gap is composed of a gap with a length of 16.8 mm and a width of 1 mm and a gap with a length of 9.576 mm and a width of 1 mm connected vertically. The vertically intersecting air gap is located directly below the dielectric resonator and at the center of the first dielectric substrate.

[0016] Preferably, the power-feeding microstrip line is two connected copper patches with matching function, one 25mm long and 2.3mm wide, and the other 10mm long and 1.6mm wide.

[0017] Preferably, the thickness of the parasitic metal strip, the metal ground plane, and the feed microstrip line is 0.035 mm.

[0018] Preferably, the dielectric resonator has a cuboid structure, with the four corner blocks and the dielectric resonator partially overlapping to form an integrated structure.

[0019] Preferably, the dielectric resonator and its corner blocks are made of 99% pure alumina. The dielectric resonator has a relative permittivity of 9.5, a loss tangent of 0.003, and a density of 3.9 g / cm³. 3 .

[0020] Preferably, the dielectric resonator is a cuboid with a length of 25.4 mm, a width of 25.4 mm, and a height of 6.35 mm, the four corner pieces are cuboids with a length of 10.6 mm, a width of 10 mm, and a height of 6.35 mm, and the overlapping part of the dielectric resonator and the corner pieces is a cuboid with a length of 3.7 mm, a width of 3.7 mm, and a height of 6.35 mm.

[0021] Preferably, the parasitic metal strip is four copper strips arranged at 0.56 mm intervals, each copper strip being 8 mm long and 1.05 mm wide.

[0022] Preferably, both the first dielectric substrate and the second dielectric substrate are made of Taconic tly-5 high-frequency board material, with a relative permittivity of 2.2 and a loss tangent of 0.0009 at 10 GHz, and a thickness of 0.762 mm.

[0023] Beneficial effects: This invention provides a design method for a wideband, low-profile, circularly polarized dielectric resonator antenna. This design significantly improves gain, reduces antenna profile height, and enhances antenna radiation efficiency by using parasitic metal strips and selecting alumina ceramic materials and resonator structures with no surface loss.

[0024] This invention cleverly combines the feed-coupled slot mode with the basic mode and the third higher-order mode of the dielectric resonator, avoiding the application of complex feed networks, achieving a simpler design, and effectively broadening the impedance and axial ratio bandwidth.

[0025] This invention boasts advantages such as novel design, wide bandwidth, low profile, and high gain. While maintaining high performance, it simplifies the manufacturing process, requiring only a stacked structure connection. Ultimately, it achieves an impedance bandwidth increase of 30.4% (4.27–5.80 GHz), an axial ratio bandwidth increase of 31.2% (4.14–5.67 GHz), a gain between 5.5 and 7.9 dBi, and an efficiency of up to 98.1%, providing a more competitive solution for applications in broadband communication systems. Attached Figure Description

[0026] Figure 1 This is a perspective view of the wideband low-profile circularly polarized dielectric resonator antenna of the present invention.

[0027] Figure 2 This is a side view of the wideband low-profile circularly polarized dielectric resonator antenna of the present invention;

[0028] Figure 3 This is a plan view of the first dielectric substrate, the second dielectric substrate, and the parasitic metal strip of the broadband low-profile circularly polarized dielectric resonator antenna of the present invention.

[0029] Figure 4 This is a plan view of the dielectric resonator of the wideband low-profile circularly polarized dielectric resonator antenna of the present invention;

[0030] Figure 5 This is a plan view of the metal ground plane of the broadband low-profile circularly polarized dielectric resonator antenna of the present invention.

[0031] Figure 6 This is a plan view of the feed microstrip line of the wideband low-profile circularly polarized dielectric resonator antenna of the present invention;

[0032] Figure 7 The |S| of the wideband low-profile circularly polarized dielectric resonator antenna in this embodiment of the invention. 11 |Map;

[0033] Figure 8 The axial ratio spectrum of the wideband low-profile circularly polarized dielectric resonator antenna in this embodiment of the invention;

[0034] Figure 9 This is the gain spectrum of a wideband low-profile circularly polarized dielectric resonator antenna in an embodiment of the present invention;

[0035] Figure 10 The efficiency spectrum of the wideband low-profile circularly polarized dielectric resonator antenna in this embodiment of the invention;

[0036] Figure 11 This is the radiation pattern of a wideband, low-profile, circularly polarized dielectric resonator antenna in an embodiment of the present invention.

[0037] In the figure: 1-Second dielectric substrate; 2-Parasitic metal strip; 3-Dielectric resonator; 4-Metal ground plane; 5-First dielectric substrate; 6-Feed microstrip line. Detailed Implementation

[0038] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, embodiments of this invention, and should not be construed as limiting the invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention. In the description of this invention, it should be understood that the terminology used is for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0039] The following is combined Figures 1-11 This invention describes a wideband, low-profile, circularly polarized dielectric resonator antenna.

[0040] Example: This example provides a wideband, low-profile circularly polarized dielectric resonator antenna, including a second dielectric substrate 1, a parasitic metal strip 2, a dielectric resonator 3, a metal ground plane 4, a first dielectric substrate 5, and a feed microstrip line 6. In this invention, the bandwidth is extended by introducing higher-order modes and combining them with feed slot modes; the gain of the extended bandwidth is improved by adding a parasitic metal strip; and the antenna efficiency is improved and the profile is reduced by introducing an alumina resonator with no surface loss.

[0041] Specifically, this wideband, low-profile, circularly polarized dielectric resonator antenna, such as Figure 1 As shown, the parasitic metal strip 2 is placed on the lower surface of the second dielectric substrate and on the dielectric resonator 3. The metal ground plane 4 is placed on the upper surface of the first dielectric substrate 5 and the dielectric resonator 3 is placed on the metal ground plane 4. The feed microstrip line 6 is placed on the lower surface of the first dielectric substrate 5.

[0042] Second dielectric substrate 1, first dielectric substrate 5, such as Figure 2 As shown, all materials are Taconic tly-5 high-frequency board. The board has a relative permittivity of 2.2, a loss tangent of 0.0009, and a thickness of h1 = h3 = 0.762 mm at 10 GHz. The dielectric resonator 3 has a thickness of h2 = 6.35 mm. The parasitic metal strip 2 and the metal ground plane 4 are both copper sheets with a thickness of 0.035 mm.

[0043] The second dielectric substrate 1 has the following plan view: Figure 3 As shown, the length l2 = 10.6 mm and the width w2 = 10 mm, the first dielectric substrate 5 has a length l1 = 60 mm and a width w1 = 60 mm, and the parasitic metal strips 2 are four strips spaced w apart. g The copper sheet has a diameter of 0.56 mm. Each copper sheet has a length of l3 = 8 mm and a width of w3 = 1.05 mm. The outermost copper sheet is 21.6 mm away from the center of the metal ground plate 4.

[0044] Dielectric resonator 3, its planar diagram is as follows Figure 4 As shown, the material is 99% pure alumina, with a relative permittivity of 9.5, a loss tangent of 0.003, and a density of 3.9 g / cm³. 3 The dielectric resonator 3 is a cuboid with a length l4 = 25.4 mm and a width w4 = 25.4 mm, plus four cuboids of the same material with a length l5 = 10.6 mm and a width w5 = 10 mm added in a clockwise order at the four corners, which overlap each other. The dimensions of the overlapping part are 3.7 mm in length and 3.7 mm in width.

[0045] Metal grounding plate 4, its plan view is as follows Figure 5 As shown, on the upper surface of the first dielectric substrate 5, a vertically intersecting air gap, 1 meter long, is etched at the center of the metal ground plane 4. s1 =16.8mm, width w s =1mm and a length l s2 = 9.576mm, width w s The components are vertically connected with gaps of 1 mm, and the intersecting gaps are directly below the dielectric resonator 3.

[0046] The feed microstrip line 6 has the following plan view. Figure 6 As shown, on the lower surface of the first dielectric substrate 5, there are two connected copper patches with matching functions, one of which is l long. f1 =25mm, width w f1 =2.3mm, another length l f2 =10mm, width w f2 =1.6mm.

[0047] Figure 7 The |S| of the wideband low-profile circularly polarized dielectric resonator antenna in this embodiment is 11 The curve shows that the antenna operates within the frequency range of 4.27–5.80 GHz. 11 The value remained below -10dB. Figure 8 The curve shows the axial ratio of the circularly polarized dielectric resonator antenna, indicating that the axial ratio is less than 3dB in the range of 4.14 to 5.67 GHz. Figure 9 This is the gain curve of a circularly polarized dielectric resonator antenna, with a peak gain of 7.9 dBi in the passband. Figure 10 This is the overall antenna efficiency curve of the filtered circularly polarized dielectric resonator antenna. Within the passband, the maximum overall antenna efficiency is 98.1%.

[0048] Figure 11 The radiation patterns of the antenna at different frequencies are given. Figure 11 In (a) corresponding to 4.3 GHz, it can be seen that the main polarization of this circularly polarized antenna is left-hand circular polarization (LHCP), and the cross polarization is right-hand circular polarization (RHCP). On the xoz and yoz planes, the maximum polarization isolation of the left and right rotations on the main lobe can reach 21.44 dB and 22.51 dB, respectively, and the axial ratio beamwidths of 3 dB can reach 107.33° and 134.31°, respectively. Figure 11(b) corresponds to 5 GHz. The maximum polarization isolation on the main lobe of the xoz plane and the yoz plane can reach 32.53 dB and 26.26 dB respectively, while the axial ratio beamwidth of 3 dB reaches 56.07° and 65.41° respectively. Figure 11 (c) corresponds to 5.56 GHz. The maximum polarization isolation on the main lobe of the xoz and yoz planes can reach 33.18 dB and 34.43 dB respectively, while the axial ratio beamwidth of 3 dB reaches 40.77° and 39.37° respectively.

[0049] In summary, this design significantly reduces the antenna profile height and improves radiation efficiency by optimizing the selection of alumina ceramic material with no surface loss and the resonator structure. The ingenious combination of the feed-coupled slot mode and the fundamental and third-order modes of the dielectric resonator avoids the application of complex feed networks, achieving a simpler design and effectively broadening the impedance and axial ratio bandwidth. The parasitic patch modulation of the third-order mode increases the radiation gain, preventing excessively low gain in some bandwidth areas. Ultimately, it achieves a 30.4% increase in impedance bandwidth (4.27–5.80 GHz), a 31.2% increase in axial ratio bandwidth (4.14–5.67 GHz), a gain between 5.5 and 7.9 dBi, and a maximum efficiency of 98.1%. This broadband, low-profile, circularly polarized dielectric resonator antenna possesses advantages such as novel design, wide bandwidth, low profile, and high gain, providing a more competitive solution for applications in broadband communication systems.

[0050] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wideband, low-profile, circularly polarized dielectric resonator antenna, characterized in that, include: A first dielectric substrate having a microstrip gap coupled feed unit; The dielectric resonator is arranged on the first dielectric substrate, and each of the four corners of the dielectric resonator has a corner block, and each corner block is arranged symmetrically with the center of the dielectric resonator as the center of symmetry; the dielectric resonator has a cuboid structure, and the four corner blocks are combined with the dielectric resonator in a partially overlapping manner to form an integral structure; Each corner block of the dielectric resonator is provided with a second dielectric substrate, and a parasitic metal strip is provided between each second dielectric substrate and the dielectric resonator; the parasitic metal strip is printed on the surface of the second dielectric substrate facing the dielectric resonator; A metal ground plane etched on the surface of the first dielectric substrate facing the dielectric resonator; And a feed microstrip line attached to the side surface of the first dielectric substrate facing away from the dielectric resonator; The metal ground plane is etched with vertically intersecting air gaps; the vertically intersecting air gaps are composed of a gap with a length of 16.8 mm and a width of 1 mm and a gap with a length of 9.576 mm and a width of 1 mm connected vertically, and the vertically intersecting air gaps are located directly below the dielectric resonator and at the center of the first dielectric substrate.

2. The wideband low-profile circularly polarized dielectric resonator antenna according to claim 1, characterized in that, The power-feeding microstrip line consists of two connected copper patches with matching function, one 25 mm long and 2.3 mm wide, and the other 10 mm long and 1.6 mm wide.

3. The wideband low-profile circularly polarized dielectric resonator antenna according to claim 2, characterized in that, The thickness of the parasitic metal strip, the metal ground plane, and the feed microstrip line is 0.035 mm.

4. The wideband low-profile circularly polarized dielectric resonator antenna according to claim 1, characterized in that, The dielectric resonator and its four corner blocks are made of 99% pure alumina. The dielectric resonator has a relative permittivity of 9.5, a loss tangent of 0.003, and a density of 3.9 g / cm³. 3 .

5. The wideband low-profile circularly polarized dielectric resonator antenna according to claim 1, characterized in that, The dielectric resonator is a cuboid with a length of 25.4 mm, a width of 25.4 mm, and a height of 6.35 mm. The four corner pieces are cuboids with a length of 10.6 mm, a width of 10 mm, and a height of 6.35 mm. The overlapping part of the dielectric resonator and the corner pieces is a cuboid with a length of 3.7 mm, a width of 3.7 mm, and a height of 6.35 mm.

6. The wideband low-profile circularly polarized dielectric resonator antenna according to claim 1, characterized in that, The parasitic metal strip consists of four copper strips spaced 0.56 mm apart, each copper strip being 8 mm long and 1.05 mm wide.

7. The broadband low-profile circularly polarized dielectric resonator antenna according to any one of claims 1 to 6, characterized in that, Both the first dielectric substrate and the second dielectric substrate are made of Taconic tly-5 high-frequency board material. The board material has a relative permittivity of 2.2 and a loss tangent of 0.0009 at 10 GHz, and the thickness of both is 0.762 mm.

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