Reconfigurable Antenna and Its Preparation Method

Abstract

The present invention provides a reconfigurable antenna and a manufacturing method thereof, relating to the technical field of antennas. The reconfigurable antenna includes: a first substrate and a second substrate which are oppositely arranged; a liquid crystal layer disposed between the first substrate and the second substrate; a first metal layer disposed between the first substrate and the liquid crystal layer; a second metal layer disposed between the second substrate and the liquid crystal layer. The first metal layer serves as a radiation patch layer of the reconfigurable antenna, and the second metal layer serves as a ground layer of the reconfigurable antenna. The first metal layer and the second metal layer are configured to provide an electric field to the liquid crystal layer so as to deflect the director of liquid crystal molecules in the liquid crystal layer.

Description

Technical Field

[0001] The present invention relates to the technical field of antennas, and particularly relates to a reconfigurable antenna and a preparation method thereof. Background Art

[0002] A reconfigurable antenna refers to an antenna that can exhibit the characteristics of multiple antennas through a certain adjustment method. The reconfigurable parameters mainly include the resonant frequency, radiation pattern, polarization of the antenna, and combinations thereof. The advantage of a reconfigurable antenna is that it can simplify a complex system, reduce costs and the number of antennas, and is conducive to realizing integration. Summary of the Invention

[0003] The present invention provides a reconfigurable antenna, which includes:

[0004] A first substrate and a second substrate disposed opposite to each other;

[0005] A liquid crystal layer disposed between the first substrate and the second substrate;

[0006] A first metal layer disposed between the first substrate and the liquid crystal layer, and the first metal layer serves as a radiation patch layer of the reconfigurable antenna;

[0007] A second metal layer disposed between the second substrate and the liquid crystal layer, and the second metal layer serves as a ground layer of the reconfigurable antenna;

[0008] The first metal layer and the second metal layer are configured to provide an electric field to the liquid crystal layer, so that the director of the liquid crystal molecules in the liquid crystal layer deflects.

[0009] Optionally, the reconfigurable antenna further includes a support structure disposed between the first substrate and the second substrate, and the orthographic projection of the liquid crystal layer on the first substrate and the orthographic projection of the first metal layer on the first substrate are both located within the region defined by the orthographic projection of the support structure on the first substrate.

[0010] Optionally, the orthographic projection of the support structure on the first substrate defines a plurality of regions that are not connected to each other.

[0011] Optionally, the orthographic projection of the support structure on the first substrate defines a plurality of regions, and at least two adjacent regions among the plurality of regions are connected to each other.

[0012] Optionally, the reconfigurable antenna further includes a microstrip line transmission line, and one end of the microstrip line transmission line is connected to the first metal layer.

[0013] Optionally, the reconfigurable antenna further includes a first barrier layer and a second barrier layer. The first barrier layer is disposed between the first substrate and the first metal layer, and the second barrier layer is disposed between the second substrate and the second metal layer.

[0014] Optionally, both the first substrate and the second substrate are flexible substrates.

[0015] Optionally, the thickness of the first substrate is 90 μm to 110 μm, 45 μm to 55 μm, or 18 μm to 22 μm, the dielectric constant of the first substrate is 4.25 to 5.19, the tangent of the dielectric loss angle of the first substrate is 0.0042 to 0.0052, and the thickness of the first metal layer and the second metal layer is 1.26 μm to 1.54 μm, 0.9 μm to 1.1 μm, 1.08 μm to 1.32 μm, or 7.2 μm to 8.8 μm.

[0016] Optionally, the thickness of the liquid crystal layer is 90 μm to 110 μm or 180 μm to 220 μm, the dielectric constant of the vertical state of the liquid crystal layer is 2.3 to 2.5, the tangent of the dielectric loss angle of the vertical state is 0.01 to 0.1, the dielectric constant of the horizontal state of the liquid crystal layer is 2.9 to 3.1, and the tangent of the dielectric loss angle of the horizontal state is 0.001 to 0.1.

[0017] Optionally, the length of the radiation patch layer is 23 mm to 28.2 mm, the length of the radiation patch layer is 23 mm to 28.2 mm, the width of the radiation patch layer is 14 mm to 18 mm, and the line width of the microstrip line is 0.39 mm to 0.46 mm or 0.43 mm to 0.53 mm.

[0018] The present invention also provides a method for manufacturing a reconfigurable antenna, which includes:

[0019] Forming a first metal layer on a first substrate;

[0020] Forming a second metal layer on a second substrate;

[0021] Aligning the first substrate with the first metal layer formed thereon and the second substrate with the second metal layer formed thereon, and forming a liquid crystal layer between the first substrate and the second substrate;

[0022] Wherein, the first metal layer is located between the first substrate and the liquid crystal layer, the second metal layer is located between the second substrate and the liquid crystal layer, the first metal layer serves as the radiation patch layer of the reconfigurable antenna, and the second metal layer serves as the ground layer of the reconfigurable antenna.

[0023] Optionally, before aligning the first substrate formed with the first metal layer and the second substrate formed with the second metal layer, the method further includes: forming a support structure on the second substrate;

[0024] Wherein, after aligning the first substrate formed with the first metal layer and the second substrate formed with the second metal layer, the orthographic projection of the liquid crystal layer on the first substrate and the orthographic projection of the first metal layer on the first substrate are both located within the region defined by the orthographic projection of the support structure on the first substrate.

[0025] Optionally, the preparation method further includes:

[0026] forming a first barrier layer on the first substrate and a second barrier layer on the second substrate;

[0027] Wherein, the first metal layer is located on a side of the first barrier layer away from the first substrate, and the second metal layer is located on a side of the second barrier layer away from the second substrate. Description of the Drawings

[0028] The drawings are used to provide a further understanding of the present invention and constitute a part of the specification. They are used together with the following specific embodiments to explain the present invention, but do not limit the present invention. In the drawings:

[0029] Figure 1 is one of the schematic diagrams of the reconfigurable antenna provided by the embodiment of the present invention;

[0030] Figure 2 is the second structural schematic diagram of the reconfigurable antenna provided by the embodiment of the present invention;

[0031] Figures 3a to 3f is the plan view of the support structure, the first metal layer and the first substrate in multiple embodiments;

[0032] Figure 4 is the flowchart of the preparation method of the reconfigurable antenna provided by the embodiment of the present invention;

[0033] Figure 5 is the schematic diagram of the preparation process of the reconfigurable antenna provided by the embodiment of the present invention;

[0034] Figure 6 is the schematic diagram of the support structure formed with a liquid crystal injection port provided by the embodiment of the present invention. Detailed Description of the Invention

[0035] The following detailed description of the specific embodiments of the present invention is provided in conjunction with the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0036] Unless otherwise defined, the technical terms or scientific terms used in the embodiments of the present invention shall have the ordinary meanings as understood by those of ordinary skill in the art to which the present invention pertains. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "comprising" or "including" mean that the elements or items appearing before this word cover the elements or items listed after this word and their equivalents, without excluding other elements or items. The terms "connected" or "coupled" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms "upper", "lower", "left", "right" and the like are only used to indicate relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0037] An embodiment of the present invention provides a reconfigurable antenna. Figure 1 One of the schematic diagrams of the reconfigurable antenna provided by the embodiment of the present invention is shown in Figure 1 As shown, the reconfigurable antenna includes: a first substrate 1, a second substrate 2, a liquid crystal layer 3, a first metal layer 4 and a second metal layer 5. The first substrate 1 and the second substrate 2 are disposed opposite to each other. The liquid crystal layer 3 is disposed between the first substrate 1 and the second substrate 2. The first metal layer 4 is disposed between the first substrate 1 and the liquid crystal layer 3. The second metal layer 5 is disposed between the second substrate 2 and the liquid crystal layer 3. The first metal layer 4 serves as a radiation patch layer of the reconfigurable antenna, and the second metal layer 5 serves as a ground layer of the reconfigurable antenna. The radiation patch layer can emit or receive radio frequency signals in response to the fed signal. The first metal layer 4 and the second metal layer 5 are configured to provide an electric field to the liquid crystal layer 3 to cause the director of the liquid crystal molecules in the liquid crystal layer 3 to deflect.

[0038] In an embodiment of the present invention, the reconfigurable antenna may be a frequency-reconfigurable antenna. The orthographic projection of the first metal layer 4 on the first substrate 1 and the orthographic projection of the second metal layer 5 on the first substrate 1 at least partially overlap, and the overlapping area covers the orthographic projection of the liquid crystal layer 3 on the first substrate 1. In this way, when corresponding voltages are applied to the first metal layer 4 and the second metal layer 5, the first metal layer 4 and the second metal layer 5 can provide an electric field to the liquid crystal layer 3. The director of the liquid crystal molecules in the liquid crystal layer 3 deflects according to this electric field, and as the electric field changes, the director of the liquid crystal molecules in the liquid crystal layer 3 can continuously deflect within a certain angular range. Since the dielectric constant of the liquid crystal layer 3 is related to the deflection angle of the director of the liquid crystal molecules in the liquid crystal layer 3, and the dielectric constant of the liquid crystal layer 3 is also related to the resonant frequency of the reconfigurable antenna, therefore, by controlling the deflection angle of the director of the liquid crystal molecules in the liquid crystal layer 3, the resonant frequency of the reconfigurable antenna can be adjusted, and the resonant frequency can be continuously adjusted within a certain range, thereby achieving the purpose of frequency reconfiguration.

[0039] The following Figures 1 to 3f will describe in detail the structure of the reconfigurable antenna according to the embodiments of the present invention. In some embodiments, both the first substrate 1 and the second substrate 2 are made of flexible substrates, so that the reconfigurable antenna has a certain flexibility and is convenient for integration with other components. For example, both the first substrate 1 and the second substrate 2 are made of flexible organic materials, such as resin materials like polyimide, polycarbonate, polyacrylate, polyetherimide, polyethersulfone, polyethylene terephthalate, and polyethylene naphthalate.

[0040] Figure 2 FIG. Figures 3a to 3f is a plan view of the support structure, the first metal layer, and the first substrate in multiple embodiments. For clarity of display, Figures 3a to 3f the liquid crystal layer 3 is hidden in Figures 2 to 3f As shown in

[0041] In an embodiment of the present invention, as Figure 2 shown, the first metal layer 4 may be located directly below the first substrate 1. The support structure 6 may be formed after the sealing glue is cured. An injection area for liquid crystal materials may be formed among the support structure 6, the first metal layer 4, and the second metal layer 5. This injection area is used for injecting liquid crystal materials to form the liquid crystal layer 3 therein. Moreover, the support structure 6 can play a supporting role to prevent the deformation of the first substrate 1 and the second substrate 2 made of flexible materials from affecting the liquid crystal layer 3.

[0042] In some embodiments, the orthographic projection of the support structure 6 on the first substrate 1 defines a plurality of regions that are not connected to each other.

[0043] In one example, the orthographic projection of the support structure 6 on the first substrate 1 defines a plurality of rectangular regions having the same shape, and the plurality of rectangular regions can be arranged in a certain preset direction. For example, as Figure 3a shown, the orthographic projection of the support structure 6 on the first substrate 1 defines two rectangular regions. The length of each rectangular region can be from 14.85 mm to 18.15 mm, for example, 16.5 mm, and the width of the rectangular region can be from 9.9 mm to 12.1 mm, for example, 11 mm. The two rectangular regions can be arranged along Figure 3a the first direction in Figure 3b ; shown again, for example, as Figure 3b shown, the orthographic projection of the support structure 6 on the first substrate 1 defines three rectangular regions. The length of each rectangular region can be from 29.7 mm to 36.3 mm, for example, 33 mm, and the width of the rectangular region can be from 6.3 mm to 7.7 mm, for example, 7 mm. The three rectangular regions can be arranged along

[0044] the second direction in Figure 3c In another example, the orthographic projection of the support structure 6 on the first substrate 1 defines a plurality of rectangular regions having the same shape, and the plurality of rectangular regions are arranged in an array. For example, as Figure 3d shown, the orthographic projection of the support structure 6 on the first substrate 1 defines four rectangular regions, and the four rectangular regions are arranged in an array, thereby forming a "field" shape. Shown again, for example, as

[0045] In some other embodiments, the orthographic projection of the support structure 6 on the first substrate 1 defines a plurality of regions, and at least two adjacent regions among the plurality of regions are connected to each other.

[0046] In one example, the orthographic projection of the support structure 6 on the first substrate 1 defines a plurality of rectangular regions having the same shape, and the plurality of rectangular regions can be arranged in a certain preset direction, and among the plurality of rectangular regions, any two adjacent rectangular regions are connected to each other. For example, as Figure 3e shown, the orthographic projection of the support structure 6 on the first substrate 1 defines two rectangular regions, and the two rectangular regions can be arranged along Figure 3e the first direction in Figure 3f ; shown, the orthographic projection of the support structure 6 on the first substrate 1 defines three rectangular regions, and the three rectangular regions can be arranged alongFigure 3f In the second direction arrangement, the middle rectangular area is connected to the rectangular areas on both sides thereof respectively.

[0047] It should be noted that in the above examples, the shape and arrangement direction of the area defined by the support structure 6 on the first substrate 1 are only illustrative and do not constitute a limitation thereto. The area defined by the orthographic projection of the support structure 6 on the first substrate 1 can also be other figures, for example, a circle, a hexagon or a triangle, etc.; the arrangement direction of the multiple areas defined by the support structure 6 on the first substrate 1 can also be along a direction intersecting with the first direction / second direction, etc.

[0048] In some embodiments, the reconfigurable antenna further includes a microstrip line transmission line L. One end of the microstrip line transmission line L is connected to the first metal layer 4, and the other end can be connected to a radio frequency connector, and the radio frequency connector can provide a radio frequency signal and a bias voltage for causing the liquid crystal molecules in the liquid crystal layer 3 to deflect in their director.

[0049] Considering that the first substrate 1 and the second substrate 2 are made of flexible materials, the first substrate 1 and the second substrate 2 may warp due to uneven stress distribution. To prevent this problem, in some embodiments, the reconfigurable antenna further includes a first barrier layer 71 and a second barrier layer 72. The first barrier layer 71 is disposed between the first substrate 1 and the first metal layer 4, and the second barrier layer 72 is disposed between the second substrate 2 and the second metal layer 5.

[0050] In the embodiments of the present invention, the first barrier layer 71 and the second barrier layer 72 can be prepared from inorganic materials. For example, SiO 2 or SiO 2 / a-Si. When the materials of the first barrier layer 71 and the second barrier layer 72 are SiO 2 , the thicknesses of the first barrier layer 71 and the second barrier layer 72 can be to For example, When the materials of the first barrier layer 71 and the second barrier layer 72 are SiO 2 / a-Si, the thicknesses of the first barrier layer 71 and the second barrier layer 72 can be to For example, the thicknesses of the first barrier layer 71 and the second barrier layer 72 can be Among them, the thickness of SiO 2 is and the thickness of a-Si is Or, the thicknesses of the first barrier layer 71 and the second barrier layer 72 can be Among them, the thickness of SiO 2 is and the thickness of a-Si is By providing a first barrier layer 71 on the first substrate 1 and a second barrier layer 72 on the second substrate 2, the stress distribution on the first substrate 1 and the second substrate 2 can be made more uniform, thereby reducing the warpage degree of the first substrate 1 and the second substrate 2. At the same time, through the first barrier layer 71 and the second barrier layer 72, the first substrate 1 and the second substrate 2 can also be protected from water and oxygen erosion, prolonging the service life of the product.

[0051] In some embodiments, since the first substrate 1 / second substrate 2 is made of a flexible material, when preparing the first substrate 1 / second substrate 2, the thickness of the flexible material formed each time is generally not more than 30 μm. If a first substrate 1 / second substrate 2 with a thickness exceeding 30 μm is to be prepared, multiple layers of flexible material need to be repeatedly formed and finally accumulated to reach the target thickness. In the embodiments of the present invention, after each formation of the flexible material layer, a third barrier layer (not shown in the figure) can be formed on the flexible material layer. The third barrier layer can be made of an inorganic material, for example, SiO 2 or SiO 2 / a-Si. By providing the third barrier layer, the warpage problem of the first substrate 1 / second substrate 2 can be further improved, and at the same time, the water and oxygen barrier performance can be enhanced.

[0052] In some embodiments, the materials of the first metal layer 4 and the second metal layer 5 can include aluminum or copper, so that the first metal layer 4 and the second metal layer 5 have relatively small conductor dielectric losses and good antenna radiation performance.

[0053] In some specific embodiments, the thickness of the first substrate 1 is 90 μm to 110 μm, 45 μm to 55 μm, or 18 μm to 22 μm, the dielectric constant of the first substrate 1 is 4.25 to 5.19, the tangent of the dielectric loss angle of the first substrate 1 is 0.0042 to 0.0052, and the thickness of the first metal layer 4 and the second metal layer 5 is 1.26 μm to 1.54 μm, 0.9 μm to 1.1 μm, 1.08 μm to 1.32 μm, or 7.2 μm to 8.8 μm.

[0054] In some specific embodiments, the thickness of the liquid crystal layer 3 is 90 μm to 110 μm or 180 μm to 220 μm, the vertical dielectric constant of the liquid crystal layer 3 is 2.3 to 2.5, the tangent of the vertical dielectric loss angle is 0.01 to 0.1, the horizontal dielectric constant of the liquid crystal layer 3 is 2.9 to 3.1, and the tangent of the horizontal dielectric loss angle is 0.001 to 0.1.

[0055] In some specific embodiments, the length of the radiation patch layer is 23 mm to 28.2 mm, the width of the radiation patch layer is 14 mm to 18 mm, and the line width of the microstrip line transmission line L is 0.39 mm to 0.46 mm or 0.43 mm to 0.53 mm.

[0056] The reconfigurable antenna according to the embodiments of the present invention will be described in detail below with some examples.

[0057] In one example, the thickness of the first substrate 1 is 90 μm to 110 μm, such as 100 μm, the dielectric constant of the first substrate 1 is 4.25 to 5.19, such as 4.72 or 4.7, and the tangent of the dielectric loss angle of the first substrate 1 is 0.0042 to 0.0052, such as 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 may be the same as those of the first substrate 1. The thickness of the first metal layer 4 and the second metal layer 5 is 1.26 μm to 1.54 μm, such as 1.4 μm. The thickness of the liquid crystal layer 3 is 90 μm to 110 μm, such as 100 μm, the vertical dielectric constant of the liquid crystal layer 3 is 2.3 to 2.5, such as 2.3616 or 2.4, the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is 0.01 to 0.1, such as 0.0128 or 0.01, the horizontal dielectric constant of the liquid crystal layer 3 is 2.9 to 3.1, such as 3.0169 or 3.01, and the tangent of the horizontal loss angle of the liquid crystal layer 3 is 0.001 to 0.1, such as 0.0035 or 0.004. The length of the radiation patch layer is 23 mm to 28.16, such as 25.6 mm, and the width of the radiation patch layer is 14.4 mm to 17.6 mm, such as 16 mm. The width of the microstrip line transmission line L is 0.378 mm to 0.462 mm, such as 0.42 mm.

[0058] In this example, the vertical dielectric constant of the liquid crystal layer 3 refers to the dielectric constant of the liquid crystal layer 3 when the long axis direction of the liquid crystal molecules in the liquid crystal layer 3 is parallel to the direction of the applied electric field; the horizontal dielectric constant of the liquid crystal layer 3 refers to the dielectric constant of the liquid crystal layer 3 when the long axis direction of the liquid crystal molecules in the liquid crystal layer 3 is perpendicular to the direction of the applied electric field; the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 refers to the tangent of the dielectric loss angle of the liquid crystal layer 3 when the long axis direction of the liquid crystal molecules in the liquid crystal layer 3 is parallel to the direction of the applied electric field; the tangent of the horizontal dielectric loss angle of the liquid crystal layer 3 refers to the tangent of the dielectric loss angle of the liquid crystal layer 3 when the long axis direction of the liquid crystal molecules in the liquid crystal layer 3 is perpendicular to the direction of the applied electric field. In other examples below, the meanings of the vertical dielectric constant, horizontal dielectric constant, tangent of the vertical dielectric loss angle, and tangent of the horizontal dielectric loss angle of the liquid crystal layer 3 are the same as those in this example, so they will not be repeated below.

[0059] In this example, with the change of the dielectric constant of the liquid crystal layer 3, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range is from 3.38 GHz to 3.76 GHz. The adjustable range of the resonant frequency f0 can reach 380 MHz. The S11 curves at the resonant frequency f0 are all less than -10 dB. The impedance bandwidth range of -10 dB is from 50 MHz to 90 MHz. The gain range at the center frequency of 3.5 GHz is from -9.79 dBi to -15.9 dBi.

[0060] In another example, the thickness of the first substrate 1 is from 45 μm to 55 μm, for example, 50 μm. The dielectric constant of the first substrate 1 is from 4.25 to 5.19, for example, 4.72 or 4.7. The tangent of the dielectric loss angle of the first substrate 1 is from 0.0042 to 0.0052, for example, 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 can be the same as those of the first substrate 1. The thickness of the first metal layer 4 and the second metal layer 5 is from 1.26 μm to 1.54 μm, for example, 1.4 μm. The thickness of the liquid crystal layer 3 is from 90 μm to 110 μm, for example, 100 μm. The vertical dielectric constant of the liquid crystal layer 3 is from 2.3 to 2.5, for example, 2.3616 or 2.4. The tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is from 0.01 to 0.1, for example, 0.0128 or 0.01. The horizontal dielectric constant of the liquid crystal layer 3 is from 2.9 to 3.1, for example, 3.0169 or 3.01. The tangent of the horizontal loss angle of the liquid crystal layer 3 is from 0.001 to 0.1, for example, 0.0035 or 0.004. The length of the radiation patch layer is from 23 mm to 28.2, for example, 25.6 mm. The width of the radiation patch layer is from 14 mm to 18 mm, for example, 16 mm. The width of the microstrip line transmission line L is from 0.39 mm to 0.46 mm, for example, 0.42 mm.

[0061] In this example, with the change of the dielectric constant of the liquid crystal layer 3, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range is from 3.42 GHz to 3.74 GHz. The adjustable range of the resonant frequency f0 can reach 320 MHz. The S11 curves at the resonant frequency f0 are all less than -10 dB. The impedance bandwidth range of -10 dB is between 90 MHz and 110 MHz. The gain range at the center frequency of 3.5 GHz is from -10.87 dBi to -15.88 dBi.

[0062] In another example, the thickness of the first substrate 1 is from 90 μm to 110 μm, for example, 100 μm, the dielectric constant of the first substrate 1 is from 4.248 to 5.192, for example, 4.72 or 4.7, and the tangent of the dielectric loss angle of the first substrate 1 is from 0.0042 to 0.0052, for example, 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 can be the same as those of the first substrate 1. The thicknesses of the first metal layer 4 and the second metal layer 5 are from 0.9 μm to 1.1 μm, for example, 1 μm. The thickness of the liquid crystal layer 3 is from 90 μm to 110 μm, for example, 100 μm, the vertical dielectric constant of the liquid crystal layer 3 is from 2.3 to 2.5, for example, 2.3616 or 2.4, the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is from 0.01 to 0.1, for example, 0.0128 or 0.01, the horizontal dielectric constant of the liquid crystal layer 3 is from 2.9 to 3.1, for example, 3.0169 or 3.01, and the tangent of the horizontal loss angle of the liquid crystal layer 3 is from 0.001 to 0.1, for example, 0.0035 or 0.004. The length of the radiating patch layer is from 23 mm to 28.2, for example, 25.6 mm, and the width of the radiating patch layer is from 14 mm to 18 mm, for example, 16 mm. The line width of the microstrip line transmission line L is from 0.39 mm to 0.46 mm, for example, 0.42 mm.

[0063] In this example, as the dielectric constant of the liquid crystal layer 3 changes, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range is from 3.36 GHz to 3.72 GHz. The adjustable range of the resonant frequency f0 can reach 320 MHz. The S11 curves at the resonant frequency f0 are all less than -10 dB. The impedance bandwidth range of -10 dB is from 60 MHz to 100 MHz, and the gain range at the center frequency of 3.5 GHz is from -11.53 dBi to -15.41 dBi.

[0064] In another example, the thickness of the first substrate 1 is from 18 μm to 22 μm, for example, 20 μm, the dielectric constant of the first substrate 1 is from 4.25 to 5.19, for example, 4.72 or 4.7, and the tangent of the dielectric loss angle of the first substrate 1 is from 0.0042 to 0.0052, for example, 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 can be the same as those of the first substrate 1. The thicknesses of the first metal layer 4 and the second metal layer 5 are from 1.08 μm to 1.32 μm, for example, 1.2 μm. The thickness of the liquid crystal layer 3 is from 90 μm to 110 μm, for example, 100 μm, the vertical dielectric constant of the liquid crystal layer 3 is from 2.3 to 2.5, for example, 2.3616 or 2.4, the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is from 0.01 to 0.1, for example, 0.0128 or 0.01, the horizontal dielectric constant of the liquid crystal layer 3 is from 2.9 to 3.1, for example, 3.0169 or 3.01, and the tangent of the horizontal loss angle of the liquid crystal layer 3 is from 0.001 to 0.1, for example, 0.0035 or 0.004. The length of the radiation patch layer is from 23 mm to 28.2 mm, for example, 25.6 mm, and the width of the radiation patch layer is from 14 mm to 18 mm, for example, 16 mm. The line width of the microstrip line transmission line L is from 0.43 mm to 0.53 mm, for example, 0.48 mm.

[0065] In this example, as the dielectric constant of the liquid crystal layer 3 changes, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range is from 3.34 GHz to 3.76 GHz. The adjustable range of the resonant frequency f0 can reach 420 MHz. At the resonant frequency f0, the S11 curve is less than -10 dB, the impedance bandwidth range of -10 dB is from 0 MHz to 60 MHz, and the gain range at the center frequency of 3.5 GHz is from -9 dBi to -15.6 dBi.

[0066] In another example, the thickness of the first substrate 1 is from 18 μm to 22 μm, for example, 20 μm, the dielectric constant of the first substrate 1 is from 4.25 to 5.19, for example, 4.72 or 4.7, and the tangent of the dielectric loss angle of the first substrate 1 is from 0.0042 to 0.0052, for example, 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 can be the same as those of the first substrate 1. The thicknesses of the first metal layer 4 and the second metal layer 5 are from 7.2 μm to 8.8 μm, for example, 8 μm. The thickness of the liquid crystal layer 3 is from 90 μm to 110 μm, for example, 100 μm, the vertical dielectric constant of the liquid crystal layer 3 is from 2.3 to 2.5, for example, 2.3616 or 2.4, the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is from 0.01 to 0.1, for example, 0.0128 or 0.01, the horizontal dielectric constant of the liquid crystal layer 3 is from 2.9 to 3.1, for example, 3.0169 or 3.01, and the tangent of the horizontal loss angle of the liquid crystal layer 3 is from 0.001 to 0.1, for example, 0.0035 or 0.004. The length of the radiation patch layer is from 23 mm to 28.2 mm, for example, 25.6 mm, and the width of the radiation patch layer is from 14 mm to 18 mm, for example, 16 mm. The line width of the microstrip line transmission line L is from 0.43 mm to 0.53 mm, for example, 0.48 mm.

[0067] In this example, as the dielectric constant of the liquid crystal layer 3 changes, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range continuously varies from 3.34 GHz to 3.74 GHz. The adjustable range of the resonant frequency f0 can reach 400 MHz. At the resonant frequency f0, the S11 curves are all less than -10 dB. The impedance bandwidth range of -10 dB is from 50 MHz to 70 MHz, and the gain range at the center frequency of 3.5 GHz is from -5.8 dBi to -14.6 dBi.

[0068] In another example, the thickness of the first substrate 1 is 18 μm to 22 μm, for example, 20 μm, the dielectric constant of the first substrate 1 is 4.25 to 5.19, for example, 4.72 or 4.7, and the tangent of the dielectric loss angle of the first substrate 1 is 0.0042 to 0.0052, for example, 0.0047 or 0.005. The thickness, dielectric constant, and tangent of the dielectric loss angle of the second substrate 2 can be the same as those of the first substrate 1. The thickness of the first metal layer 4 and the second metal layer 5 is 1.08 μm to 1.32 μm, for example, 1.2 μm. The thickness of the liquid crystal layer 3 is 180 μm to 220 μm, for example, 200 μm, the vertical dielectric constant of the liquid crystal layer 3 is 2.3 to 2.5, for example, 2.3616 or 2.4, the tangent of the vertical dielectric loss angle of the liquid crystal layer 3 is 0.01 to 0.1, for example, 0.0128 or 0.01, the horizontal dielectric constant of the liquid crystal layer 3 is 2.9 to 3.1, for example, 3.0169 or 3.01, and the tangent of the horizontal loss angle of the liquid crystal layer 3 is 0.001 to 0.1, for example, 0.0035 or 0.004. The length of the radiation patch layer is 23 mm to 28.2 mm, for example, 25.6 mm, and the width of the radiation patch layer is 14 mm to 18 mm, for example, 16 mm. The line width of the microstrip line transmission line L is 0.43 mm to 0.53 mm, for example, 0.48 mm.

[0069] In this example, as the dielectric constant of the liquid crystal layer 3 changes, the resonant frequency f0 of the reconfigurable antenna is continuously adjustable, and the adjustment range continuously varies from 3.30 GHz to 3.74 GHz. The adjustable range of the resonant frequency f0 can reach 340 MHz. The S11 curves at the resonant frequency f0 are all less than -10 dB. The impedance bandwidth range of -10 dB is 50 MHz to 70 MHz, and the gain range at the center frequency of 3.5 GHz is -3 dBi to -10.9 dBi.

[0070] By using the reconfigurable antenna of the embodiment of the present invention, the continuous adjustment of the resonant frequency can be realized by using the liquid crystal layer 3, so that the tuning function of the reconfigurable antenna can be integrated with the reconfigurable antenna itself, optimizing the impedance matching, thus eliminating the radio frequency switch and the antenna tuner, reducing the number of the above components used in mobile terminals such as mobile phones, and at the same time improving the radiation efficiency of the reconfigurable antenna.

[0071] The embodiment of the present invention also provides a preparation method of a reconfigurable antenna. Figure 4 As shown in the flowchart of the preparation method of the reconfigurable antenna provided by the embodiment of the present invention, Figure 4 The preparation method includes:

[0072] S11. Form a first metal layer on the first substrate.

[0073] S12. Form a second metal layer on the second substrate.

[0074] In steps S11 and S12, metal aluminum or copper can be deposited in a low-temperature environment by methods such as magnetron sputtering. After the patterning process, a first metal layer and a second metal layer are formed. The stress of the first metal layer and the second metal layer deposited in the low-temperature environment is small, which can reduce the warpage degree of the first substrate and the second substrate.

[0075] It should be noted that the sequence of steps S11 and S12 is not limited. Step S11 can be before step S12, after step S12, or carried out simultaneously.

[0076] S13. Align the first substrate with the first metal layer formed thereon and the second substrate with the second metal layer formed thereon, and form a liquid crystal layer between the first substrate and the second substrate. In this step, a support structure can be first formed on the second substrate, so that after the first substrate and the second substrate are aligned, a liquid crystal filling region is formed among the first substrate, the second substrate, and the support structure. Then, liquid crystal filling is performed by the dropping method to form a liquid crystal layer between the first substrate and the second substrate, which will be specifically introduced in detail below and will not be elaborated here.

[0077] Among them, the first metal layer is located between the first substrate and the liquid crystal layer, and the second metal layer is located between the second substrate and the liquid crystal layer. The first metal layer serves as the radiation patch layer of the reconfigurable antenna, and the second metal layer serves as the ground layer of the reconfigurable antenna (such as the grounding layer and the reflection layer of the reconfigurable antenna).

[0078] In the embodiment of the present invention, the reconfigurable antenna can be a frequency reconfigurable antenna. The orthographic projection of the first metal layer on the first substrate and the orthographic projection of the second metal layer on the first substrate at least partially overlap, and the overlapping region covers the orthographic projection of the liquid crystal layer on the first substrate. In this way, when corresponding voltages are applied to the first metal layer and the second metal layer, the first metal layer and the second metal layer can provide an electric field to the liquid crystal layer. The director of the liquid crystal molecules in the liquid crystal layer deflects according to this electric field, and as the electric field changes, the director of the liquid crystal molecules in the liquid crystal layer can continuously deflect within a certain angular range. Since the dielectric constant of the liquid crystal layer is related to the deflection angle of the director of the liquid crystal molecules in the liquid crystal layer, and the dielectric constant of the liquid crystal layer is also related to the resonant frequency of the reconfigurable antenna, the resonant frequency of the reconfigurable antenna can be adjusted by controlling the deflection angle of the director of the liquid crystal molecules in the liquid crystal layer, and the resonant frequency can be continuously adjusted within a certain range, thereby achieving the purpose of frequency reconfiguration.

[0079] Figure 5 is a schematic diagram of the preparation process of the reconfigurable antenna provided by the embodiment of the present invention. The following will be combined with Figure 4 and Figure 5A detailed description of the preparation method of the embodiments of the present invention is given. In some specific embodiments, both the first substrate 1 and the second substrate 2 are flexible substrates. The manufacturing method includes:

[0080] S21. Provide two high-temperature glass substrates 8, respectively coat a flexible material on the two high-temperature glass substrates 8 through a coating process, cure the coated flexible material at a high temperature, and obtain the first substrate 1 and the second substrate 2 after post-cleaning. Of course, when providing the glass substrate 8, the glass substrate 8 can also be subjected to pre-cleaning, drying and other processes.

[0081] In the above process, the flexible material formed each time is generally not more than 30 μm. If it is necessary to prepare the first substrate 1 with a thickness exceeding 30 μm, it is necessary to repeatedly form multiple flexible material layers and finally accumulate to reach the target thickness. In the embodiments of the present invention, after each flexible material layer is formed, a third barrier layer can be formed on the flexible material layer. The third barrier layer can include inorganic materials and can be prepared by chemical vapor deposition. By providing the third barrier layer, the warping problem of the first substrate 1 / second substrate 2 can be further improved, and at the same time, the water and oxygen barrier can be strengthened.

[0082] S22. Form a first metal layer 4 on the first substrate 1.

[0083] S23. Form a second metal layer 5 on the second substrate 2.

[0084] S24. Form a support structure 6 on the second substrate 2 formed with the second metal layer 5. Among them, after the first substrate 1 formed with the first metal layer 4 and the second substrate 2 formed with the second metal layer 5 are aligned, the orthographic projection of the liquid crystal layer 3 on the first substrate 1 and the orthographic projection of the first metal layer 4 on the first substrate 1 are both located within the area defined by the orthographic projection of the support structure 6 on the first substrate 1.

[0085] In step S24, the support structure 6 can be formed on the surface of the second substrate 2 or on the surface of the second metal layer 5. Preferably, in the embodiments of the present invention, the solution of forming the support structure 6 on the surface of the second metal layer 5 is adopted, which is beneficial to simplifying the preparation process. After the first substrate 1 formed with the first metal layer 4 and the second substrate 2 formed with the support structure 6 and the second metal layer 5 are aligned, an injection area can be formed between the first metal layer 4, the second metal layer 5 and the support structure 6, and this injection area is used for injecting liquid crystal material to form a liquid crystal layer 3 therein.

[0086] Figure 6 Schematic diagram of the support structure with an injection port provided by the embodiments of the present invention, as Figure 6As shown, in step S24, a sealant can be coated on the second metal layer 5 in a vacuum environment, and after curing, a support structure 6 is obtained. Among them, spherical spacers with a diameter of 100 μm are mixed in the sealant (the mixing ratio of the glue is 1:100).

[0087] S25. Align the first substrate 1 formed with the first metal layer 4 and the second substrate 2 formed with the second metal layer 5, and form a liquid crystal injection region between the first substrate 1 and the second substrate 2.

[0088] In step S25, the first substrate 1 and the second substrate 2 can inject liquid crystal into the liquid crystal injection region formed between the first metal layer 4, the second metal layer 5, and the support structure 6 by the dropping method. Therefore, in step S24, while forming the support structure 6, a liquid crystal injection port H is also formed on the support structure 6, and the liquid crystal injection port H is internally connected to the support structure 6. In this way, in step S25, liquid crystal can be injected into the interior of the support structure 6 (i.e., the aforementioned liquid crystal injection region) through the liquid crystal injection port H to form a liquid crystal layer 3 inside the support structure 6. After that, through processes such as leveling and sealing, and laser cutting, step S25 is completed. Among them, the liquid crystal injection process can be carried out in a vacuum environment to ensure that the liquid crystal is completely degassed.

[0089] In the embodiment of the present invention, the length of the liquid crystal injection port H can be 5.4 mm to 6.6 mm, such as 6 mm, and the width of the liquid crystal injection port H can be 5.4 mm to 6.6 mm, such as 6 mm. For example, as Figure 6 shown in the left figure in [reference], the support structure 6 includes two rectangular support structures and two liquid crystal injection ports H. Each liquid crystal injection port H is internally connected to a rectangular support structure, and the two liquid crystal injection ports H are respectively arranged on opposite sides of the support structure 6. By arranging the support structure 6 in this way, liquid crystal can be injected into the interior of the support structure 6 through the two liquid crystal injection ports H respectively, which is beneficial to improving the uniformity of the cell gap of the liquid crystal layer 3.

[0090] As Figure 6 shown in the right figure in [reference], the support structure 6 includes three rectangular support parts and three liquid crystal injection ports H. Each liquid crystal injection port H is internally connected to a rectangular support part, and the three liquid crystal injection ports H can be arranged on the same side of the support structure 6. By arranging the support structure 6 in this way, liquid crystal can be injected into the interior of the support structure 6 through the three liquid crystal injection ports H respectively, which can further improve the uniformity of the cell gap of the liquid crystal layer 3.

[0091] After step S25, the glass substrate 8 can be removed by laser lift-off to obtain a reconfigurable antenna.

[0092] In some specific embodiments, before step S22 and step S23, the following can also be carried out:

[0093] S3. Form a first barrier layer 71 on the first substrate 1 and a second barrier layer 72 on the second substrate 2.

[0094] Among them, the first metal layer 4 is located on the side of the first barrier layer 71 away from the first substrate 1, and the second metal layer 5 is located on the side of the second barrier layer 72 away from the second substrate 2.

[0095] In step S3, at a temperature of 390 °C, the SiO2 material (with a thickness of ) or SiO2 / a-Si (with a thickness of ) can be deposited on the first substrate 1 and the second substrate 2 by plasma-enhanced chemical vapor deposition to obtain the first barrier layer 71 and the second barrier layer 72.

[0096] In some other specific embodiments, when preparing the first metal layer 4 and the second metal layer 5, the flexible printed circuit (FPC) manufacturing process can also be used to laminate patterned metal materials on the first substrate 1 and the second substrate 2 to form the first metal layer 4 and the second metal layer 5.

[0097] In some other specific embodiments, the first substrate 1 and the second substrate 2 can also be made of polyethylene terephthalate (PET). When preparing the first metal layer 4 and the second metal layer 5, a groove for setting the liquid crystal layer 3 can be etched on the first substrate 1 or the second substrate 2 through an etching process first, and then a metal material can be electroplated on the inner wall of the groove to obtain the first metal layer 4 and the second metal layer 5. The manufacturing processes of the above two methods are simpler and are beneficial to cost reduction.

[0098] It can be understood that the above embodiments are merely exemplary embodiments adopted to illustrate the principle of the present invention. However, the present invention is not limited thereto. For those of ordinary skill in the art, various modifications and improvements can be made without departing from the spirit and essence of the present invention, and these modifications and improvements are also regarded as the protection scope of the present invention.

Claims

1. A reconfigurable antenna, characterized in that, comprising: A first substrate and a second substrate arranged opposite to each other; both the first substrate and the second substrate include multiple flexible material layers, and a third barrier layer is further provided between two adjacent flexible material layers; A liquid crystal layer disposed between the first substrate and the second substrate; A first metal layer disposed between the first substrate and the liquid crystal layer, and the first metal layer serves as a radiation patch layer of the reconfigurable antenna; A second metal layer disposed between the second substrate and the liquid crystal layer, and the second metal layer serves as a ground layer of the reconfigurable antenna; The first metal layer and the second metal layer are configured to provide an electric field to the liquid crystal layer so that the director of the liquid crystal molecules in the liquid crystal layer deflects; The reconfigurable antenna further includes a support structure, the support structure is disposed between the first substrate and the second substrate, and the orthographic projection of the liquid crystal layer on the first substrate and the orthographic projection of the first metal layer on the first substrate are both located within the area defined by the orthographic projection of the support structure on the first substrate; a liquid crystal filling port is provided on the support structure, and the liquid crystal filling port is communicated with the inside of the support structure; both the length and the width of the liquid crystal filling port are 5.4 mm - 6.6 mm; The reconfigurable antenna further includes a first barrier layer and a second barrier layer, the first barrier layer is disposed between the first substrate and the first metal layer, and the second barrier layer is disposed between the second substrate and the second metal layer; the first barrier layer, the second barrier layer and the third barrier layer all include inorganic materials; When the materials of the first barrier layer and the second barrier layer are SiO 2 , the thicknesses of the first barrier layer and the second barrier layer are 2000 Å - 6000 Å; when the materials of the first barrier layer and the second barrier layer are SiO 2 / a-Si, the thicknesses of the first barrier layer and the second barrier layer are 2015 Å - 6015 Å.

2. The reconfigurable antenna according to claim 1, characterized in that, The orthographic projection of the support structure on the first substrate defines multiple regions, and the multiple regions are not communicated with each other.

3. The reconfigurable antenna according to claim 1, characterized in that, The orthographic projection of the support structure on the first substrate defines multiple regions, and at least two adjacent regions among the multiple regions are communicated with each other.

4. The reconfigurable antenna according to any one of claims 1 to 3, characterized in that, The reconfigurable antenna further includes a microstrip transmission line, and one end of the microstrip transmission line is connected to the first metal layer.

5. The reconfigurable antenna according to any one of claims 1 to 3, characterized in that, Both the first substrate and the second substrate are made of flexible substrates.

6. The reconfigurable antenna according to claim 4, characterized in that, The thickness of the first substrate is 90 μm to 110 μm, 45 μm to 55 μm or 18 μm to 22 μm, the dielectric constant of the first substrate is 4.25 to 5.19, the tangent of the dielectric loss angle of the first substrate is 0.0042 to 0.0052, and the thickness of the first metal layer and the second metal layer is 1.26 μm to 1.54 μm, 0.9 μm to 1.1 μm, 1.08 μm to 1.32 μm or 7.2 μm to 8.8 μm.

7. The reconfigurable antenna according to claim 6, characterized in that, The thickness of the liquid crystal layer is 90 μm to 110 μm or 180 μm to 220 μm. The vertical dielectric constant of the liquid crystal layer is 2.3 to 2.5, and the vertical dielectric loss tangent is 0.01 to 0.

1. The horizontal dielectric constant of the liquid crystal layer is 2.9 to 3.1, and the horizontal dielectric loss tangent is 0.001 to 0.

1.

8. The reconfigurable antenna according to claim 7, wherein, the length of the radiation patch layer is 23 mm to 28.2 mm, the width of the radiation patch layer is 14 mm to 18 mm, and the line width of the microstrip line is 0.39 mm to 0.46 mm or 0.43 mm to 0.53 mm.

9. A method for manufacturing a reconfigurable antenna according to any one of claims 1-8, wherein, the manufacturing method includes: forming a first metal layer on a first substrate; forming a second metal layer on a second substrate; pairing the first substrate with the first metal layer formed thereon and the second substrate with the second metal layer formed thereon, and forming a liquid crystal layer between the first substrate and the second substrate; wherein, the first metal layer is located between the first substrate and the liquid crystal layer, the second metal layer is located between the second substrate and the liquid crystal layer, the first metal layer serves as the radiation patch layer of the reconfigurable antenna, and the second metal layer serves as the ground layer of the reconfigurable antenna.

10. The manufacturing method according to claim 9, wherein, before pairing the first substrate with the first metal layer formed thereon and the second substrate with the second metal layer formed thereon, it further includes: forming a support structure on the second substrate; wherein, after pairing the first substrate with the first metal layer formed thereon and the second substrate with the second metal layer formed thereon, the orthographic projection of the liquid crystal layer on the first substrate and the orthographic projection of the first metal layer on the first substrate are both located within the region defined by the orthographic projection of the support structure on the first substrate.

11. The manufacturing method according to claim 9, wherein, the manufacturing method further includes: forming a first barrier layer on the first substrate and a second barrier layer on the second substrate; wherein, the first metal layer is located on the side of the first barrier layer away from the first substrate, and the second metal layer is located on the side of the second barrier layer away from the second substrate.

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