Flexible antenna and method of manufacturing the same

Abstract

The present application relates to a kind of flexible antennas, including polymer matrix, radiation patch, ground layer, electrode layer and bias power supply, polymer matrix includes first sub-matrix and second sub-matrix adjacent along the direction of extension, first sub-matrix also includes filler, filler includes ferroelectric material particle and heat-conducting filler particle, radiation patch, ground layer and electrode layer are all arranged on the surface of first sub-matrix and mutually spaced apart between each other, bias power supply and radiation patch, electrode layer form current loop, for adjusting the dielectric constant of first sub-matrix.The present application also relates to a kind of preparation method of flexible antenna.The present application can regulate the working frequency of flexible antenna, guarantee that flexible antenna can still work normally under curved surface state;At the same time, the heat generated by flexible antenna when working will not be accumulated in first sub-matrix, even more will not cause the interface separation of first sub-matrix and radiation patch, ground layer, electrode layer, guarantee the reliability and service life of flexible antenna.

Description

Technical Field

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

[0002] Traditional flexible antennas are based on polymer films such as polyimide, liquid crystal polymer, and polydimethylsiloxane, with a radiating patch and ground layer bonded to the surface. When these flexible antennas are bent and deformed, their size and shape change, leading to corresponding changes in electrical parameters such as their operating frequency, radiation pattern, and gain. This, in turn, causes the operating frequency of the flexible antenna to change when curved, deviating from the designed operating frequency and causing it to malfunction.

[0003] Furthermore, the radiating patch and grounding layer are both made of metal materials such as copper and silver, resulting in significant differences in the thermal expansion coefficients between the substrate and radiating patch, and between the substrate and grounding layer. As a power device, flexible antennas generate significant heat during operation. Furthermore, since the radiating patch and grounding layer are both made of metal with high thermal conductivity, while the substrate is made of polymer with lower thermal conductivity, the generated heat tends to concentrate within the substrate. When this heat accumulates within the substrate and reaches a certain level, it can cause separation between the substrate and radiating patch, and between the substrate and grounding layer, rendering the flexible antenna inoperable and affecting its reliability and service life. Summary of the Invention

[0004] Based on this, it is necessary to provide a flexible antenna with adjustable frequency, good reliability and long service life and a preparation method thereof to address the above problems.

[0005] A flexible antenna comprising:

[0006] A polymer matrix, the polymer matrix comprising a first sub-matrix and a second sub-matrix adjacent to each other along an extension direction, the first sub-matrix further comprising a filler, the filler comprising ferroelectric material particles and thermally conductive filler particles;

[0007] a radiation patch, a ground layer, and an electrode layer, wherein the radiation patch, the ground layer, and the electrode layer are all disposed on the surface of the first sub-substrate, and the radiation patch, the ground layer, and the electrode layer are spaced apart from each other;

[0008] A bias power supply, wherein the bias power supply, the radiation patch, and the electrode layer form a current loop for adjusting the dielectric constant of the first sub-substrate.

[0009] In the flexible antenna of the present invention, the polymer matrix comprises a first sub-matrix and a second sub-matrix. Ferroelectric material particles and thermally conductive filler particles are distributed within the first sub-matrix, giving it excellent thermal conductivity and an adjustable dielectric constant. The second sub-matrix is ​​a pure polymer matrix, exhibiting excellent flexibility. Consequently, even after the radiating patch, ground layer, and electrode layer are disposed on the surface of the first sub-matrix, the flexible antenna maintains excellent flexibility. Furthermore, when the operating frequency of the flexible antenna changes due to bending deformation, the bias power supply on the flexible antenna can adjust the dielectric constant of the first sub-matrix to maintain the same operating frequency as in the flat state, ensuring that the flexible antenna can continue to operate normally despite bending deformation.

[0010] Furthermore, the filler distributed within the first sub-substrate reduces its coefficient of thermal expansion, minimizing the differences in thermal expansion coefficients between the first sub-substrate and the radiating patch, the first sub-substrate and the ground layer, and the first sub-substrate and the electrode layer. Furthermore, because the first sub-substrate also has excellent thermal conductivity, heat generated during operation by the flexible antenna does not accumulate within the first sub-substrate, nor does it cause separation at the interfaces between the first sub-substrate and the radiating patch, the first sub-substrate and the ground layer, or the first sub-substrate and the electrode layer, thereby ensuring the reliability and service life of the flexible antenna.

[0011] In one embodiment, there are multiple first sub-substrates, and at least one of the radiation patch, the ground layer, and the electrode layer is disposed on the surface of each first sub-substrate.

[0012] In one embodiment, the radiation patch and the ground layer are arranged on different surfaces of the first sub-substrate, the radiation patch and the electrode layer are arranged on the same surface of the first sub-substrate, and the electrode layer is arranged on the surface of the first sub-substrate facing away from the radiation patch.

[0013] In one embodiment, the mass fraction of the filler in the first sub-matrix is ​​1%-30%;

[0014] And / or, the mass ratio of the ferroelectric material particles to the thermally conductive filler particles in the filler is 1:1-4:1.

[0015] In one embodiment, the particle size of the filler is less than or equal to 100 nm.

[0016] In one embodiment, the thermal conductivity of the thermally conductive filler particles is greater than or equal to 45 W / (m·K), and the thermally conductive filler particles include at least one of aluminum nitride particles, silicon nitride particles, boron nitride particles, and silicon carbide particles;

[0017] And / or, the ferroelectric material particles include at least one of lead zirconate titanate particles, barium strontium titanate particles, barium titanate particles, and sodium potassium niobate particles.

[0018] In one embodiment, the matrix material of the first sub-matrix is ​​a first polymer, the matrix material of the second sub-matrix is ​​a second polymer, and the first polymer and the second polymer are the same polymer.

[0019] In one embodiment, the thickness of the polymer matrix is ​​100 μm-500 μm;

[0020] And / or, the thickness of the radiation patch is 9 μm-36 μm;

[0021] And / or, the thickness of the ground layer is 9 μm-36 μm;

[0022] And / or, the thickness of the electrode layer is 9 μm-36 μm.

[0023] A method for preparing a flexible antenna, comprising:

[0024] The first polymer, ferroelectric material particles and thermal conductive filler particles are prepared into a first mixed liquid, and the second polymer is prepared into a second mixed liquid;

[0025] forming the first mixed liquid and the second mixed liquid on a substrate to obtain a polymer prefabricated matrix, wherein the polymer prefabricated matrix includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along an extension direction;

[0026] Drying the polymer prefabricated matrix to obtain a polymer matrix, wherein the polymer matrix includes a first sub-matrix and a second sub-matrix adjacently arranged along an extension direction;

[0027] A radiation patch, a ground layer, and an electrode layer spaced apart from each other are formed on the surface of the first sub-substrate, and the electrode layer, the radiation patch, and a bias power supply form a current loop to obtain a flexible antenna.

[0028] In one embodiment, the step of forming the first mixed liquid and the second mixed liquid on a substrate to obtain a polymer prefabricated matrix is ​​specifically as follows:

[0029] The first mixed liquid and the second mixed liquid are printed onto the substrate by a 3D printing method to obtain the polymer prefabricated matrix.

[0030] In one embodiment, the method of forming mutually spaced radiation patches, grounding layers, and electrode layers on the surface of the first sub-substrate includes at least one of a mask screen printing method, a mask PVD sputtering method, and a 3D printing method.

[0031] The method of the present invention for preparing a polymer matrix including a first sub-matrix and a second sub-matrix is ​​simple and easy to operate. A radiation patch, a ground layer and an electrode layer spaced apart from each other are formed on the first sub-matrix of the polymer matrix to obtain a flexible antenna with adjustable frequency, good reliability and long service life, which is suitable for industrial production. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of the structure of the flexible antenna of the present invention;

[0033] Figure 2 for Figure 1 A top view of the main structure of the flexible antenna shown;

[0034] Figure 3 for Figure 1 A bottom view of the main structure of the flexible antenna is shown.

[0035] In the figure: 10, polymer matrix; 20, radiation patch; 30, ground layer; 40, electrode layer; 50, bias power supply; 101, first sub-matrix; 102, second sub-matrix. DETAILED DESCRIPTION

[0036] The flexible antenna and its manufacturing method provided by the present invention will be further described below with reference to the accompanying drawings.

[0037] The dielectric constant of the polymer matrix is ​​constant, while ferroelectric materials have high dielectric tunability. Therefore, adding ferroelectric particles to the polymer matrix can impart dielectric tunability. Simultaneously, adding thermally conductive filler particles to the polymer matrix can also impart high thermal conductivity. However, both ferroelectric and thermally conductive filler particles are hard materials with high bending stiffness. Adding both ferroelectric and thermally conductive filler particles to the polymer matrix inevitably reduces the flexibility of the polymer matrix, affecting the bending radius of the flexible antenna and, consequently, the conformal fit of the flexible antenna to the platform's curved surface.

[0038] like Figures 1 to 3 As shown, the flexible antenna provided by the present invention includes a main structure and a bias power supply 50. The main structure comprises a polymer matrix 10, a radiating patch 20, a ground layer 30, and an electrode layer 40. The polymer matrix 10 comprises a first sub-matrix 101 and a second sub-matrix 102 adjacently arranged along the extension direction. The first sub-matrix 101 also contains fillers, including ferroelectric material particles and thermally conductive filler particles. This ensures that the first sub-matrix 101 has excellent thermal conductivity and an adjustable dielectric constant, while the second sub-matrix 102 is a pure polymer matrix and exhibits excellent flexibility.

[0039] Specifically, the radiation patch 20, the ground layer 30 and the electrode layer 40 are arranged at intervals on the surface of the first sub-substrate 101 of the polymer matrix 10, and the bias power supply 50, the radiation patch 20 and the electrode layer 40 form a current loop for adjusting the dielectric constant of the first sub-substrate 101.

[0040] Specifically, the radiation patch 20 and the electrode layer 40 are respectively connected to the bias power supply 50 through metal wires, and the radiation patch 20 and the electrode layer 40 are welded through metal wires to form a capacitor with the first sub-base 101 .

[0041] Specifically, the radiation patch 20 and the ground layer 30 are welded together through an SMA connector or the like, so that the current is grounded through the ground layer 30 .

[0042] Furthermore, because the polymer matrix 10 includes the first sub-matrix 101 and the second sub-matrix 102 along a plane, the first sub-matrix 101 and the second sub-matrix 102 form a complete polymer matrix 10 for carrying functional components. The second sub-matrix 102 is a pure polymer matrix without any functional components on its surface. Therefore, the flexible antenna retains good flexibility due to the flexibility of the second sub-matrix 102, and can achieve "conformal" placement with the curved surface of the platform.

[0043] When the operating main frequency of the flexible antenna changes due to "conformity" with the curved surface of the platform, the dielectric constant of the first sub-substrate 101 can be adjusted by the bias power supply 50 on the flexible antenna to restore its operating main frequency to the designed operating main frequency in the planar state, so as to ensure that the flexible antenna can still work normally in the bent and deformed state.

[0044] Furthermore, the filler distributed within the first sub-substrate 101 reduces the thermal expansion coefficient of the first sub-substrate 101, minimizing the differences in thermal expansion coefficients between the first sub-substrate 101 and the radiating patch 20, the first sub-substrate 101 and the grounding layer 30, and the first sub-substrate 101 and the electrode layer 40. Furthermore, because the first sub-substrate 101 also has excellent thermal conductivity, heat generated during operation of the flexible antenna does not accumulate within the first sub-substrate 101, nor does it cause separation at the interfaces between the first sub-substrate 101 and the radiating patch 20, the first sub-substrate 101 and the grounding layer 30, or the first sub-substrate 101 and the electrode layer 40, thereby ensuring the reliability and service life of the flexible antenna.

[0045] Furthermore, the number of the first sub-matrices 101 in the polymer matrix 10 may be one or more, preferably multiple.

[0046] When the number of the first sub-matrix 101 in the polymer matrix 10 is one, the radiation patch 20, the ground layer 30 and the electrode layer 40 are all arranged on the surface of the same first sub-matrix 101.

[0047] When the number of the first sub-matrix 101 in the polymer matrix 10 is more than one, as shown in Figure 2 and Figure 3 , at least one of the radiation patch 20, the ground layer 30 and the electrode layer 40 is arranged on the surface of each of the first sub-matrix 101. It can be understood that at this time, the first sub-matrix 101 is also arranged spaced apart from each other, so that the part between the first sub-matrix 101 arranged spaced apart from each other is the second sub-matrix 102, further increasing the area of the second sub-matrix 102 in the polymer matrix 10, and further assisting in improving the flexibility of the flexible antenna.

[0048] Of course, the radiation patch 20, the ground layer 30 and the electrode layer 40 arranged on the surface of the first sub-matrix 101 can be located on the same side of the surface of the polymer matrix 10, or on the two opposite surfaces of the polymer matrix 10. When located on the same side of the surface of the polymer matrix 10, the radiation patch 20, the ground layer 30 and the electrode layer 40 can also be located on the surface of the same first sub-matrix 101, but are preferably arranged on the surface of different first sub-matrix 101.

[0049] In order to further increase the area of the second sub-matrix 102 in the polymer matrix 10, as shown in Figure 1 , the radiation patch 20 and the ground layer 30 are arranged on the surface of different first sub-matrix 101, the radiation patch 20 and the electrode layer 40 are arranged on the surface of the same first sub-matrix 101, and the electrode layer 40 is arranged on the surface of the first sub-matrix 101 away from the radiation patch 20.

[0050] In order to further increase the area of the second sub-matrix 102, the area of each first sub-matrix 101 is the same as the shape of the functional elements of the radiation patch 20, the ground layer 30 and the electrode layer 40 arranged on the surface thereof.

[0051] It should be noted that the number of the radiation patch 20, the ground layer 30 and the electrode layer 40 can be one or more, and when there are more than one, each functional element is preferably arranged on the surface of a first sub-matrix 101, as shown in Figure 1 , the number of the ground layer 30 is two, and the two ground layers 30 are arranged on the surface of a first sub-matrix 101.

[0052] It can be understood that there can be multiple radiation patches 20, and the number of ground layers 30 and electrode layers 40 is configured accordingly based on the number of radiation patches 20 to form a corresponding array.

[0053] It should be noted that the shapes of the radiation patch 20, the ground layer 30 and the electrode layer 40 are not limited, and are preferably as follows: Figure 2 and Figure 3 In the shape shown, the ground layer 30 is a quadrilateral, and the radiation patch 20 and the electrode layer 40 are both quadrilaterals with a hemispherical end surface at one end of the quadrilateral.

[0054] Furthermore, in order to ensure the dielectric adjustability and thermal conductivity of the first sub-substrate 101 while taking into account flexibility, the mass of the filler is preferably 1%-30% of the mass of the first sub-substrate 101, and the particle size of the filler is preferably less than or equal to 100nm, wherein the mass ratio of ferroelectric material particles to thermal conductive filler particles in the filler is preferably 1:1-4:1.

[0055] Furthermore, the mass of the filler is preferably 10%-20% of the mass of the first sub-matrix 101, more preferably 15%, the particle size of the filler is preferably less than or equal to 80nm, more preferably 50nm-80nm, and the mass ratio of the ferroelectric material particles to the thermally conductive filler particles in the filler is more preferably 2:1, so as to improve the dielectric adjustability and thermal conductivity of the first sub-matrix 101 while better balancing the flexibility of the polymer matrix 10.

[0056] In one or more embodiments, the ferroelectric material particles include at least one of lead zirconate titanate particles, barium strontium titanate particles, barium titanate particles, and sodium potassium niobate particles.

[0057] In order to better improve the thermal conductivity of the first sub-substrate 101, in one or more embodiments, the thermal conductivity coefficient of the thermally conductive filler particles is preferably greater than or equal to 45W / (m·K), including at least one of aluminum oxide particles, aluminum nitride particles, silicon nitride particles, boron nitride particles, and silicon carbide particles.

[0058] Furthermore, the matrix material of the first sub-matrix 101 is a first polymer, and the matrix material of the second sub-matrix 102 is a second polymer. The first polymer and the second polymer both include at least one of liquid crystal polymer, polyimide, polyetheretherketone, polyphenylene sulfide, polytetrafluoroethylene, polyester, and polydimethylsiloxane.

[0059] Since the first sub-substrate 101 and the second sub-substrate 102 constitute a complete polymer matrix 10, in order to ensure the strength of the polymer matrix 10 and prevent faults, breakages, etc. from occurring between the first sub-substrate 101 and the second sub-substrate 102 when the flexible antenna is bent and "conforms" to the curved surface of the platform, the first polymer and the second polymer are preferably the same polymer.

[0060] In addition, the materials of the radiation patch 20, the ground layer 30 and the electrode layer 40 are all metal materials such as copper, silver, and platinum. In order to further ensure the flexibility of the flexible antenna and the working performance of the components, the thickness of the polymer matrix 10 is preferably 100μm-500μm, the thickness of the radiation patch 20 is 9μm-36μm, the thickness of the ground layer 30 is 9μm-36μm, and the thickness of the electrode layer 40 is 9μm-36μm.

[0061] Therefore, the frequency tuning rate of the flexible antenna of the present invention can reach more than 10%, and further can reach 50%, the thermal conductivity can reach more than 10W / (m·K), and further can reach 80W / (m·K), and the bending radius can be as small as 10mm, further can be as small as 5mm, and further can be as small as 1mm.

[0062] The present invention also provides a method for preparing the flexible antenna, comprising:

[0063] S1, preparing a first polymer, ferroelectric material particles and thermal conductive filler particles into a first mixed liquid, and preparing a second polymer into a second mixed liquid;

[0064] S2, forming the first mixed liquid and the second mixed liquid on a substrate to obtain a polymer prefabricated matrix, wherein the polymer prefabricated matrix includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along an extension direction;

[0065] S3, drying the polymer prefabricated matrix to obtain a polymer matrix 10, wherein the polymer matrix 10 includes a first sub-matrix 101 and a second sub-matrix 102 adjacently arranged along an extension direction;

[0066] S4, forming a radiation patch 20, a ground layer 30, and an electrode layer 40 spaced apart from each other on the surface of the first sub-substrate 101, and making the electrode layer 40, the radiation patch 20 and a bias power supply 50 form a current loop to obtain a flexible antenna.

[0067] In step S1 , the first mixed liquid and the second mixed liquid may further include a curing agent.

[0068] The method of 3D printing can precisely control the shape and distribution of the first sub-matrix 101 and the second sub-matrix 102 in the polymer matrix 10, and meanwhile, can ensure the uniformity of the dielectric constant, thermal conductivity and thermal expansion coefficient of the first sub-matrix 101. In step S2, the step of forming the first mixed solution and the second mixed solution on a substrate to obtain a polymer pre-matrix is specifically: preferably, the first mixed solution and the second mixed solution are printed on the substrate by the method of 3D printing to obtain the polymer pre-matrix.

[0069] In step S2, the substrate includes at least one of a glass substrate and a PMMA substrate, has a small surface roughness and a low peeling strength, and can be peeled off to obtain the antenna under the assistance of an external force after the flexible antenna is obtained.

[0070] In step S3, the polymer pre-matrix is preferably baked at 60-120℃ for 2-4 hours to obtain the polymer matrix 10.

[0071] In step S4, the materials of the radiation patch 20, the ground layer 30 and the electrode layer 40 are metal materials, and the method for forming the radiation patch 20, the ground layer 30 and the electrode layer 40 on the surface of the first sub-matrix 101 includes at least one of a mask screen printing method, a mask PVD sputtering method and a 3D printing method.

[0072] Therefore, the method for preparing the flexible antenna is simple and easy to operate, and meanwhile, the dielectric constant uniformity tolerance of the first sub-matrix 101 in the polymer matrix 10 of the flexible antenna is ±0.1-±0.3, the thermal conductivity uniformity tolerance is ±3W / (m·K)-±5W / (m·K), and the thermal expansion coefficient uniformity tolerance is ±3ppm / ℃-±10ppm / ℃.

[0073] In the following, the flexible antenna and the preparation method thereof will be further described through the following specific examples.

[0074] Example 1

[0075] 20g of polyurethane particles are dissolved in 200g of dimethylformamide (DMF) solvent, and then mixed with 1g of barium strontium titanate particles with a particle size of 100nm and 1g of aluminum nitride particles with a particle size of 100nm, and the magnetic stirring is performed at a rotating speed of 150r / min for 24 hours to form a first mixed solution. 20g of polyurethane particles are dissolved in 200g of DMF solvent, and then mixed uniformly to form a second mixed solution.

[0076] The first mixed solution and the second mixed solution are printed on the substrate by the method of 3D printing according to the following formula: Figure 2 and Figure 3The first and second pre-sub-bases are arranged adjacent to each other along the extension direction. After baking at 80°C for 4h, the polymer pre-sub-bases are dried to form a polymer substrate with a thickness of 100μm, which includes the first and second sub-bases arranged adjacent to each other along the extension direction.

[0077] The surface of the polymer substrate is plated with copper by PVD sputtering method. The copper layer is thickened to 12μm by electroplating. The copper layer on the surface of the second sub-base is removed by photolithography process to form the radiating patch, the ground layer and the electrode layer on the surface of the first sub-base. Finally, the electrode layer, the radiating patch and the bias power source form a current loop to obtain the flexible antenna.

[0078] Example 2

[0079] 30g of polyurethane particles are dissolved in 600g of DMF solvent, and then mixed with 6g of potassium sodium niobate particles with a particle size of 50nm and 3g of boron nitride particles with a particle size of 50nm. The first mixed solution is formed by magnetic stirring at a speed of 100r / min for 12 hours. 30g of polyurethane particles are dissolved in 600g of DMF solvent, and then mixed uniformly to form the second mixed solution.

[0080] The first and second mixed solutions are selectively printed on the substrate according to the design pattern shown in Figure 2 and Figure 3 The first and second pre-sub-bases are arranged adjacent to each other along the extension direction. After baking at 80°C for 4h, the polymer pre-sub-bases are dried to form a polymer substrate with a thickness of 100μm, which includes the first and second sub-bases arranged adjacent to each other along the extension direction.

[0081] The first and second mixed solutions are selectively printed on the substrate according to the design pattern shown in

[0082] Example 3

[0083] 20g of polydimethylsiloxane is mixed with 2g of curing agent, 1g of barium strontium titanate particles with a particle size of 100nm and 1g of silicon nitride particles with a particle size of 100nm. The first mixed solution is formed by magnetic stirring at a speed of 150r / min for 24 hours. 20g of polydimethylsiloxane is mixed with 2g of curing agent to form the second mixed solution.

[0084] The first and second mixed solutions are selectively printed on the substrate according to the design pattern shown in Figure 2 and Figure 3 The designed pattern shown is selectively printed on a substrate to obtain a polymer prefabricated matrix, which includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along the extension direction. The prefabricated polymer matrix is ​​then baked at 80°C for 4 hours and dried to form a polymer matrix with a thickness of 100 μm. The polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along the extension direction.

[0085] Copper is plated on the surface of a polymer substrate using the PVD sputtering method. The copper layer is thickened to 12 μm through electroplating. The copper layer on the surface of the second sub-substrate is then removed through a photolithography process. A radiation patch, a ground layer, and an electrode layer are formed on the surface of the first sub-substrate. Finally, the electrode layer, the radiation patch, and the bias power supply form a current loop to obtain a flexible antenna.

[0086] Example 4

[0087] 30g of polyurethane particles were dissolved in 600g of DMF solvent, mixed with 3g of 50nm sodium potassium niobate particles and 3g of 80nm boron nitride particles, and stirred with a magnetic stirrer at 100 rpm for 12 hours to form a first mixed solution. 30g of polyurethane particles were dissolved in 600g of DMF solvent and mixed thoroughly to form a second mixed solution.

[0088] The first mixed solution and the second mixed solution are prepared by 3D printing as follows: Figure 2 and Figure 3 The designed pattern shown is selectively printed on a substrate to obtain a polymer prefabricated matrix, which includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along the extension direction. The prefabricated polymer matrix is ​​then baked at 120°C for 2 hours and dried to form a polymer matrix with a thickness of 150 μm. The polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along the extension direction.

[0089] The 3D printing method is used to print metal silver paste on the surface of the first sub-substrate of the polymer matrix to obtain a radiation patch, a ground layer and an electrode layer with a thickness of 15 μm. Finally, the electrode layer, the radiation patch and the bias power supply form a current loop to obtain a flexible antenna.

[0090] Example 5

[0091] 30g of liquid crystal polymer particles were dissolved in 600g of DMF solvent, mixed with 3.6g of 50nm sodium potassium niobate particles and 0.9g of 60nm boron nitride particles, and stirred with a magnetic stirrer at 100 rpm for 12 hours to form a first mixed solution. 30g of polyurethane particles were dissolved in 600g of DMF solvent and mixed thoroughly to form a second mixed solution.

[0092] The first mixed solution and the second mixed solution are prepared by 3D printing as follows: Figure 2 and Figure 3 The designed pattern shown is selectively printed on a substrate to obtain a polymer prefabricated matrix, which includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along the extension direction. The prefabricated polymer matrix is ​​then baked at 120°C for 2 hours and dried to form a polymer matrix with a thickness of 200 μm. The polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along the extension direction.

[0093] The 3D printing method is used to print metal silver paste on the surface of the first sub-substrate of the polymer matrix to obtain a radiation patch, a ground layer and an electrode layer with a thickness of 15 μm. Finally, the electrode layer, the radiation patch and the bias power supply form a current loop to obtain a flexible antenna.

[0094] Example 6

[0095] 30g of polyetheretherketone particles were dissolved in 600g of DMF solvent, mixed with 5g of 60nm barium titanate particles and 2.5g of 50nm aluminum nitride particles, and stirred with a magnetic stirrer at 100 rpm for 12 hours to form a first mixed solution. 30g of polyurethane particles were dissolved in 600g of DMF solvent and mixed thoroughly to form a second mixed solution.

[0096] The first mixed solution and the second mixed solution are prepared by 3D printing as follows: Figure 2 and Figure 3 The designed pattern shown is selectively printed on a substrate to obtain a polymer prefabricated matrix, which includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along the extension direction. The prefabricated polymer matrix is ​​then baked at 120°C for 2 hours and dried to form a polymer matrix with a thickness of 100 μm. The polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along the extension direction.

[0097] The 3D printing method is used to print metal silver paste on the surface of the first sub-substrate of the polymer matrix to obtain a radiation patch, a ground layer and an electrode layer with a thickness of 15 μm. Finally, the electrode layer, the radiation patch and the bias power supply form a current loop to obtain a flexible antenna.

[0098] Example 7

[0099] 30g of polyimide particles were dissolved in 600g of DMF solvent, mixed with 4.5g of 80nm lead zirconate titanate particles and 1.5g of 50nm silicon carbide particles, and stirred with a magnetic stirrer at 100 rpm for 12 hours to form a first mixed solution. 30g of polyurethane particles were dissolved in 600g of DMF solvent and mixed thoroughly to form a second mixed solution.

[0100] The first mixed solution and the second mixed solution are prepared by 3D printing as follows: Figure 2 and Figure 3 The designed pattern shown is selectively printed on a substrate to obtain a polymer prefabricated matrix, which includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along the extension direction. The prefabricated polymer matrix is ​​then baked at 120°C for 2 hours and dried to form a polymer matrix with a thickness of 100 μm. The polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along the extension direction.

[0101] The 3D printing method is used to print metal silver paste on the surface of the first sub-substrate of the polymer matrix to obtain a radiation patch, a ground layer and an electrode layer with a thickness of 15 μm. Finally, the electrode layer, the radiation patch and the bias power supply form a current loop to obtain a flexible antenna.

[0102] Example 8

[0103] The difference between Example 8 and Example 1 is that the mass of the barium strontium titanate particles and the aluminum nitride particles in Example 8 are both 5 g.

[0104] Example 9

[0105] The difference between Example 9 and Example 1 is that in Example 9, the mass of the barium strontium titanate particles is 0.5 g, and the mass of the aluminum nitride particles is 1.5 g.

[0106] Example 10

[0107] The difference between Example 10 and Example 1 is that the particle sizes of the barium strontium titanate particles and the aluminum nitride particles in Example 10 are both 150 μm.

[0108] Comparative Example 1

[0109] The difference between Comparative Example 1 and Example 1 is that the polymer matrix of Comparative Example 1 is entirely 3D printed by the first mixed liquid.

[0110] The flexible antennas of Examples 1-10 and Comparative Example 1 were subjected to performance tests, and the results are shown in Table 1, wherein the functional elements in Table 1 refer to the radiation patch, the ground layer, and the electrode layer, ie, the copper layer.

[0111] Table 1

[0112]

[0113]

[0114] The technical features of the above-mentioned embodiments can be combined arbitrarily. In order to make the description concise, not all possible combinations of the technical features in the above-mentioned embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0115] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A flexible antenna, characterized in that: include: A polymer matrix, the polymer matrix comprising a first sub-matrix and a second sub-matrix adjacent to each other along an extension direction, the first sub-matrix further comprising a filler, the filler comprising ferroelectric material particles and thermally conductive filler particles; a radiation patch, a ground layer, and an electrode layer, wherein the radiation patch, the ground layer, and the electrode layer are all disposed on the surface of the first sub-substrate, and the radiation patch, the ground layer, and the electrode layer are spaced apart from each other, and the radiation patch, the electrode layer, and the first sub-substrate form a capacitor; A bias power supply, wherein the bias power supply, the radiation patch, and the electrode layer form a current loop for adjusting the dielectric constant of the first sub-substrate.

2. The flexible antenna according to claim 1, wherein There are multiple first sub-sub-bases, and at least one of the radiation patch, the ground layer, and the electrode layer is disposed on the surface of each first sub-base.

3. The flexible antenna according to claim 2, wherein: The radiation patch and the ground layer are arranged on different surfaces of the first sub-substrate, the radiation patch and the electrode layer are arranged on the same surface of the first sub-substrate, and the electrode layer is arranged on the surface of the first sub-substrate away from the radiation patch.

4. The flexible antenna according to any one of claims 1 to 3, characterized in that: The mass fraction of the filler in the first sub-matrix is ​​1%-30%; And / or, the mass ratio of the ferroelectric material particles to the thermally conductive filler particles in the filler is 1:1-4:

1.

5. The flexible antenna according to any one of claims 1 to 3, characterized in that: The particle size of the filler is less than or equal to 100 nm.

6. The flexible antenna according to any one of claims 1 to 3, characterized in that: The thermal conductivity of the thermally conductive filler particles is greater than or equal to 45 W / (m·K), and the thermally conductive filler particles include at least one of aluminum nitride particles, silicon nitride particles, boron nitride particles, and silicon carbide particles; And / or, the ferroelectric material particles include at least one of lead zirconate titanate particles, barium strontium titanate particles, barium titanate particles, and sodium potassium niobate particles.

7. The flexible antenna according to any one of claims 1 to 3, characterized in that: The matrix material of the first sub-matrix is ​​a first polymer, the matrix material of the second sub-matrix is ​​a second polymer, the first polymer and the second polymer are the same polymer, and the first polymer and the second polymer both include at least one of liquid crystal polymer, polyimide, polyetheretherketone, polyphenylene sulfide, polytetrafluoroethylene, polyester, and polydimethylsiloxane.

8. The flexible antenna according to any one of claims 1 to 3, characterized in that: The thickness of the polymer matrix is ​​100 μm-500 μm; And / or, the thickness of the radiation patch is 9 μm-36 μm; And / or, the thickness of the ground layer is 9 μm-36 μm; And / or, the thickness of the electrode layer is 9 μm-36 μm.

9. A method for preparing a flexible antenna according to any one of claims 1 to 8, characterized in that: include: The first polymer, ferroelectric material particles and thermal conductive filler particles are prepared into a first mixed liquid, and the second polymer is prepared into a second mixed liquid; forming the first mixed liquid and the second mixed liquid on a substrate to obtain a polymer prefabricated matrix, wherein the polymer prefabricated matrix includes a first prefabricated sub-matrix and a second prefabricated sub-matrix adjacent to each other along an extension direction; Drying the polymer prefabricated matrix to obtain a polymer matrix, wherein the polymer matrix includes a first sub-matrix and a second sub-matrix adjacent to each other along an extension direction; A radiation patch, a ground layer, and an electrode layer spaced apart from each other are formed on the surface of the first sub-substrate, and the electrode layer, the radiation patch, and a bias power supply form a current loop to obtain a flexible antenna.

10. The method for preparing a flexible antenna according to claim 9, wherein: The step of forming the first mixed liquid and the second mixed liquid on a substrate to obtain a polymer prefabricated matrix is ​​specifically: using a 3D printing method to print the first mixed liquid and the second mixed liquid onto the substrate to obtain the polymer prefabricated matrix.

11. The method for preparing a flexible antenna according to claim 9, wherein: The method for forming mutually spaced radiation patches, grounding layers, and electrode layers on the surface of the first sub-substrate includes at least one of a mask screen printing method, a mask PVD sputtering method, and a 3D printing method.

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