A stereolithography-based ultra-wide bandwidth wave-beam metamaterial antenna

Abstract

The application provides a kind of based on stereolithography ultra-wide bandwidth beam medium resonant antenna, belong to antenna design field, including double-layer PCB structure and medium resonator, wherein, double-layer PCB structure includes first upper surface copper clad (4), second upper surface copper clad (5), lower surface copper clad (3), medium substrate (2);Medium resonator structure includes ceramic medium block (1), first slot (6), second slot (7);First, second upper surface copper clad is located on the upper surface of medium substrate, and first, second upper surface copper clad is microstrip line;Lower surface copper clad is the ground plane corresponding to microstrip line, and ground plane has gap with medium resonator;Ceramic medium block has first and second slot, and two slots are equal in size, wherein, first slot is located above medium resonator, and second slot is located below medium resonator.The application can realize complex structure of medium material conformal coating by stereolithography additive manufacturing technology, and realize the impedance bandwidth of ultra-wide band.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of antenna design, and particularly relates to a three-dimensional photolithography-based ultra-wideband beam dielectric resonator antenna. BACKGROUND

[0002] The dielectric resonator antenna is an antenna formed by dielectric material resonance to cause radiation, and has the advantages of high efficiency, light weight, small influence of environment metal, etc. However, the traditional dielectric resonator antenna is a frequency-variable antenna, has a narrow bandwidth and a small half-power beam angle, and is manufactured by a subtractive process, so the cost is high and it is difficult to realize a complex structure to enhance the antenna performance, which greatly limits the application scenarios of the dielectric resonator antenna. Therefore, it is of great significance to realize an ultra-wideband and wide beam while retaining the advantages of the dielectric resonator antenna to meet the needs of modern radar, communication and other radio frequency technologies. The bandwidth of the traditional rectangular antenna is related to the dielectric constant of the material, and the single resonance point bandwidth is about 5% to 10%. At present, in order to overcome the narrow bandwidth, the methods such as reducing the quality factor, stacking the dielectric, and multi-resonance mode radiation are usually used. However, these methods have limited bandwidth expansion range and are not suitable for ultra-wideband scenarios, and have the disadvantages of increased antenna volume and distorted directional diagram. In terms of the half-power beam angle, the methods such as mode regulation or parasitic loading are usually used, but there are also defects such as low available bandwidth of wide beam and reduced peak gain. At the same time, in terms of the manufacturing method, in recent years, additive manufacturing methods such as fused deposition manufacturing are proposed to carry out printing of complex antenna structures, but the application is greatly challenged by the few available materials, high micro-porosity of the formed structure, and low equivalent dielectric constant. SUMMARY

[0003] To solve the above technical problems, the application provides an ultra-wideband beam dielectric resonator antenna based on a three-dimensional photolithography technology. In order to achieve the above object, the technical scheme adopted by the application is as follows:

[0004] The ultra-wideband beam dielectric resonator antenna based on the three-dimensional photolithography comprises a double-layer PCB structure and a dielectric resonator, wherein the double-layer PCB structure comprises a first upper surface copper cladding, a second upper surface copper cladding, a lower surface copper cladding and a dielectric substrate; the dielectric resonator structure comprises a ceramic dielectric block, a first slot and a second slot; the first and second upper surface copper claddings are located on the upper surface of the dielectric substrate, and the first and second upper surface copper claddings are microstrip lines; the lower surface copper cladding is a ground plane corresponding to the microstrip line, and the ground plane has a gap with the dielectric resonator; the ceramic dielectric block has the first and second slots, and the sizes of the two slots are equal, wherein the first slot is located above the dielectric resonator and has a certain distance from the upper surface of the dielectric resonator, and the second slot is located below the dielectric resonator, and the lower surface of the second slot is flush with the lower surface of the ceramic dielectric block and in contact with the dielectric substrate.

[0005] The application has the following beneficial effects:

[0006] The application realizes an ultra-wide bandwidth beam dielectric resonator antenna by using a double-layer PCB structure and a stereolithography-based ceramic, the antenna can be used in a communication base station or a radar system, and the dielectric resonator with a complex structure, low cost and short manufacturing period is realized by a stereolithography technology; the antenna realizes a multi-mode ultra-wide impedance bandwidth by single pole feeding, the feeding microstrip structure is parallel to the antenna radiation direction, and wide radiation beam is realized; the electromagnetic field distribution in the dielectric is regulated by slotting the dielectric resonator, the working bandwidth is further expanded, and the distortion of the radiation pattern caused by the introduction of high-order working mode is corrected by the strong electric field in the slot; the directivity of the antenna is further improved, and the radiation pattern of the antenna is improved by introducing a gap between the ground edge and the dielectric resonator. On the basis of the advantages of the traditional dielectric resonator antenna, such as high efficiency and less environmental influence, the antenna has the advantages of ultra-wide band, wide radiation beam, small volume, simple structure and the like, and different frequency bands can be covered by changing the length of the feeding structure and the size of the dielectric resonator. The antenna can support the performance improvement of the communication base station or the radar system.

[0007] The stereolithography additive manufacturing technology can realize the complex structure of the dielectric material, and the shortcomings of low material density and low equivalent dielectric constant of the additive manufacturing technology such as fused deposition modeling are overcome. The impedance bandwidth of the ultra-wide band is realized by changing the structure to regulate the resonant mode and frequency. However, due to the characteristics of the dielectric resonator antenna, the introduction of multiple resonant modes will inevitably cause distortion of the radiation pattern. The antenna realizes the correction of the radiation pattern and the wide radiation beam by analyzing the distribution of the electromagnetic field in the dielectric and adjusting the structure of the dielectric resonator and the dielectric substrate. The antenna can be used in wall-penetrating radar, life-detecting radar, mobile communication base station, ultra-wide band communication system and the like, and has the advantages of ultra-wide band, light and small size, wide beam, high gain flatness, low cost, fast manufacturing and the like. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 The manufacturing process diagram of the stereolithography ceramic dielectric resonator in the ultra-wide bandwidth beam dielectric resonator antenna based on stereolithography of the application;

[0009] Figure 2 The overall structure diagram of the ultra-wide bandwidth beam dielectric resonator antenna based on stereolithography of the application;

[0010] Figure 3 The X-Z plane side view of the ultra-wide bandwidth beam dielectric resonator antenna based on stereolithography of the application;

[0011] Figure 4 The Y-Z plane side view of the ultra-wide bandwidth beam dielectric resonator antenna based on stereolithography of the application;

[0012] Figure 5 Top view of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention;

[0013] Figure 6 Bottom view of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention;

[0014] Figure 7 Top view of the antenna processing size chart provided by the embodiment of the present invention;

[0015] Figure 8 Bottom view of the antenna processing size chart provided by the embodiment of the present invention;

[0016] Figure 9 Side view of the antenna processing size chart provided by the embodiment of the present invention;

[0017] Figure 10 S11 comparison of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention and the media resonator antenna without slot in the media center;

[0018] Figure 11 Simulation and actual measurement gain chart of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention;

[0019] Figure 12 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 2.6GHz, respectively;

[0020] Figure 13 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 3.4GHz, respectively;

[0021] Figure 14 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 4.2GHz, respectively;

[0022] Figure 15 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 5.0GHz, respectively;

[0023] Figure 16 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 5.8GHz, respectively;

[0024] Figure 17 E-plane main polarization and cross polarization pattern of the stereolithography based ultra-wide bandwidth beam media resonant antenna of the present invention at 6.6GHz, respectively;

[0025] Figure 18An E-plane half-power beamwidth-frequency plot of the stereolithography-based ultra-wide bandwidth beam-metamaterial resonant antenna of the present application. DETAILED DESCRIPTION

[0026] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0027] As shown in Figure 2 , Figure 3 , Figure 4 , Figure 5 , Figure 6 , a structural schematic diagram and side, planar and elevational views of the stereolithography-based ultra-wide bandwidth beam-metamaterial resonant antenna of the present application are given. The stereolithography-based ultra-wide bandwidth beam-metamaterial resonant antenna of the present application comprises a double-layer PCB structure and a dielectric resonator, wherein the double-layer PCB structure comprises a first upper surface copper cladding 4, a second upper surface copper cladding 5, a lower surface copper cladding 3 and a dielectric substrate 2, and the dielectric resonator structure comprises a ceramic dielectric block 1 and a first slot 6 and a second slot 7 on the ceramic dielectric block 1.

[0028] As shown in Figure 1 , the dielectric resonator is made of stereolithography additive manufacturing method, and the process comprises mixing nano-alumina ceramic powder, photosensitive resin, photoinitiator and dispersant by ball milling, stirring and defoaming.

[0029] The alumina ceramic powder is mixed by 300 nm and 500 nm alumina powder with a mass ratio of 3:1, and the addition of an appropriate amount of large particle size powder can effectively reduce the number of alumina particles in unit volume, reduce the interaction between particles, and reduce the viscosity of the ceramic slurry. The resin, photoinitiator and dispersant are 1,6-hexanediol diacrylate (HDDA), trimethylbenzoyl-diphenyl phosphine oxide (TPO) and propylene glycol methyl ether acetate (PGMEA), respectively. The slurry preparation process is to mix alumina powder (60wt%), resin (37wt%), dispersant (1wt%) and photoinitiator (2wt%), and then put it into a planetary ball mill for 4 hours. After stirring and defoaming, the slurry is cured by 405 nm ultraviolet light, and the single-layer exposure energy is 100 mJ / cm 2, the printing layer thickness is 50μm. After printing, ultrasonic cleaning is performed using 95% concentration alcohol, post-curing is performed using the same wavelength light, and debinding and densification are completed by sintering at 600℃ (heating rate 2℃ / min, holding time 2h) and sintering at 1600℃ (heating rate 2℃ / min, holding time 3h) respectively, and finally the ceramic dielectric block 1 is formed.

[0030] The ground plane edge of the lower surface copper clad 3 of the dielectric substrate 2 has a gap with the dielectric resonator to improve the pattern imbalance caused by the monopole feed.

[0031] As shown in Figure 3 , Figure 4 , Figure 9 The dielectric substrate 2 is a rectangular epoxy glass fiber plate, with a dielectric constant of 4.35, a loss tangent of 0.015, a thickness of 1.6mm, a length of 43.7mm, and a width of 49mm. The first upper surface copper clad 4, the second upper surface copper clad 5, and the lower surface copper clad 3 of the substrate are all 0.035mm electrolytic copper.

[0032] As shown in Figure 5 The first and second upper surface copper clads 4 and 5 are microstrip lines, including a feed port section and an impedance transformation section, with characteristic impedances of 50Ohm and 70.71Ohm respectively. The impedance transformation section is flush with the upper surface of the second slot 7 below the dielectric resonator to achieve broadband matching to the dielectric resonator.

[0033] As shown in Figure 6 The lower surface copper clad 3 is the ground plane corresponding to the microstrip line, and the ground plane has a certain gap with the dielectric resonator, which helps to improve the radiation directivity of the dielectric resonator.

[0034] As shown in Figure 5 The ceramic dielectric block 1 is a slotted rectangular photocured ceramic dielectric block, and the first and second slots are equal in size. The first slot 6 is located above the dielectric resonator and has a certain distance from the upper surface of the dielectric resonator. The second slot 7 is located below the dielectric resonator, and the bottom surface of the second slot 7 is flush with the bottom surface of the ceramic dielectric block and in contact with the dielectric substrate 2. By introducing the first slot 6 and the second slot 7, the electric field distribution of the high-order resonant mode can be effectively controlled, the bandwidth can be further matched, and the electric field distribution in the dielectric resonator can be enhanced, effectively improving the radiation pattern distortion problem caused by the introduction of high-order resonant modes.

[0035] As shown in Figure 7 , Figure 8 , Figure 9 The antenna size diagram is shown in top view, bottom view, and side view, in which the upper and lower surface copper structures of the double-layer PCB structure of the embodiment are respectively made of top and bottom copper foils, and the specific design size is:

[0036] (a), the upper surface is covered with copper using a top layer of copper foil, the top layer of copper foil is a rectangular copper foil with two different widths, the length of the rectangular copper foil is 3.5mm, the width is 3mm, the length of the rectangular copper foil is 17.2mm, and the width is 1.58mm;

[0037] (b), the lower surface is covered with copper using a bottom layer of copper foil, the bottom layer of copper foil is a rectangular copper foil with a length of 10mm and a width of 49mm, and the gap width between the upper edge of the copper foil and the edge of the dielectric substrate 2 is 0.7mm;

[0038] (c), the two layers of copper foil together form a microstrip structure, wherein the first upper surface copper 4 corresponds to a microstrip line with a characteristic impedance of 50Ohm, and the second upper surface copper structure 5 has a microstrip line with a characteristic impedance of 70.71Ohm;

[0039] The ceramic dielectric block 1 of the embodiment is a rectangular alumina photocurable ceramic dielectric block formed by stereolithography, and the specific size is designed as follows:

[0040] The length of the ceramic dielectric block 1 is 33mm, the width is 24mm, the dielectric constant is 8.3, the loss tangent is 0.0031, the two slots are equal in size, both are rectangular with a length of 10mm and a width of 12mm, the lower edge of the lower rectangular second slot 7 is flush with the lower edge of the dielectric resonator, and the upper rectangular first slot 6 is 6mm away from the lower rectangular second slot 7.

[0041] As shown in Figure 10 The antenna S11 graph provided by the embodiment of the application contains simulation and measurement results, and the case without slotting of the dielectric resonator is provided as a comparison, it can be seen that the slotting effectively increases the impedance bandwidth of the antenna, and the -10dB impedance bandwidth of the antenna is 2.58GHz to 6.74GHz, which is an ultra-wideband antenna with a relative bandwidth of 89.27%.

[0042] As shown in Figure 11 The antenna gain-frequency graph provided by the embodiment of the application is shown, it can be seen that the gain of the antenna is greater than 1.5dB in the whole working frequency range.

[0043] As shown in Figures 12-17 The E-plane patterns of the antenna at 2.6GHz, 3.4GHz, 4.2GHz, 5.0GHz, 5.8GHz and 6.6GHz are shown, it can be seen that the antenna has good directivity, wide radiation beam, small pattern distortion, and practical significance.

[0044] As shown in Figure 18 The half-power beamwidth-frequency graph of the antenna is shown, it can be seen that the half-power beamwidth of the antenna is greater than 120 degrees in the whole frequency range, and the maximum angle can reach 300 degrees, which can effectively ensure the coverage range of radar, communication base station and the like.

[0045] Those skilled in the art can easily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application. Any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A stereolithography-based ultra-wide bandwidth wave-beam metamaterial resonant antenna, characterized by, The application relates to a double-layer PCB structure and a dielectric resonator, wherein the double-layer PCB structure comprises a first upper surface copper coating, a second upper surface copper coating, a lower surface copper coating and a dielectric substrate; the dielectric resonator structure comprises a ceramic dielectric block, a first slot and a second slot; the first and second upper surface copper coatings are located on the upper surface of the dielectric substrate and are microstrip lines; the lower surface copper coating is a ground plane corresponding to the microstrip lines, and the ground plane has a gap with the dielectric resonator; the ceramic dielectric block has the first and second slots, and the two slots are equal in size, wherein the first slot is located above the dielectric resonator and has a certain distance from the upper surface of the dielectric resonator, and the second slot is located below the dielectric resonator, and the lower surface of the second slot is flush with the lower surface of the ceramic dielectric block and is in contact with the dielectric substrate.

2. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 1, wherein, The dielectric resonator is manufactured by a stereolithography additive manufacturing method, and the manufacturing method specifically comprises the following steps: mixing nano ceramic powder and a photosensitive dispersing agent, stirring and defoaming, using a photocuring 3D printer for stereolithography, then ultrasonic cleaning, secondary post-curing, high-temperature sintering to remove the resin in the ceramic, and finally forming the ceramic dielectric block.

3. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 1, wherein, The dielectric substrate is a rectangular epoxy glass fiber plate with a dielectric constant of 4.35, a loss tangent of 0.015, a thickness of 1.6 mm, a length of 43.7 mm and a width of 49 mm.

4. The stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna of claim 1, wherein, The upper and lower surface copper coatings are both electrolytic copper with a thickness of 0.035 mm.

5. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 1, wherein, The first and second upper surface copper coatings are respectively a feeding port part and an impedance transformation part, and the impedance transformation part is flush with the upper surface of the second slot below the dielectric resonator.

6. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 5, wherein, The feeding port part and the impedance transformation part have characteristic impedances of 50 Ohm and 70.71 Ohm respectively.

7. A stereolithography-based ultra-wide bandwidth wave-beam metamaterial resonant antenna according to claim 1, wherein, The upper and lower surface copper coatings of the double-layer PCB structure are designed by using top and bottom copper foils respectively.

8. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 7, wherein, The specific dimensions of the top and bottom copper foils are as follows: The first and second upper surface copper coatings are two sections of top copper foils, and the two sections of top copper foils are rectangular copper foils with different widths, wherein one section of the rectangular copper foil has a length of 3.5 mm and a width of 3 mm, and the other section of the rectangular copper foil has a length of 17.2 mm and a width of 1.58 mm; The bottom copper foil is a rectangular copper foil with a length of 10 mm and a width of 49 mm, and the upper edge of the bottom copper foil has a gap with the edge of the dielectric substrate with a width of 0.7 mm; and the two copper foils together form a microstrip structure.

9. The stereolithography-based ultra-wide bandwidth wave-beam metamaterial resonant antenna of claim 1, wherein, The ceramic dielectric block has a length of 33 mm, a width of 24 mm, a dielectric constant of 8.3 and a loss tangent of 0.0031.

10. A stereolithography-based ultra-wide bandwidth wave-beam meta- surface antenna according to claim 1, wherein, The first and second slots are both rectangular with a length of 10 mm and a width of 12 mm, and the first slot is 6 mm away from the second slot.

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