Curved surface antenna structure and preparation method thereof

Abstract

The invention relates to the technical field of curved antenna processing, and discloses a curved antenna structure and a preparation method thereof. The preparation method of the curved surface antenna structure comprises the following steps: dividing a plurality of to-be-processed areas on the surface of a curved surface substrate; acquiring surface height information of the to-be-processed area; dividing the to-be-processed area into a plurality of fitting areas; according to the obtained surface height information, conductive metal slurry is printed in a fitting area of the curved-surface substrate to form antenna units, and the multiple antenna units are fitted to form a single antenna pattern; a resistance structure is formed between adjacent antenna patterns. According to the method, firstly, the curved surface substrate is divided into the multiple to-be-processed areas, the surface height information of each to-be-processed area is obtained, then the to-be-processed areas are divided into the multiple fitting areas, and then according to the obtained surface height information, conductive metal slurry filling is carried out with the small fitting areas as basic units, so that the application of intermediary materials is saved, and the machining efficiency is improved. Damage to the base material is avoided, and high conformal and reliable connection with the curved surface substrate is achieved.

Description

Technical Field

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

[0002] In order to blend in with the aircraft structure, the antenna can be designed to be a curved surface conforming to the aircraft's outer surface, that is, a conformal curved antenna, to meet the antenna's requirements for scanning area, radiation performance, and installation location, and to achieve the development of airborne antennas towards multi-functional integration, lightness, and high performance. In addition, the antenna also needs a radiating surface to radiate or receive electromagnetic waves, that is, matching resistance is required to ensure the impedance matching performance of the antenna. Therefore, a complete curved antenna structure requires an antenna pattern and a corresponding resistance unit.

[0003] At present, the main methods for making conformal antennas on curved surface structures are: Laser Direct Structuring (LDS) and laser micro-cladding; the main methods for making resistors on curved surface structures are: laser resistance adjustment and manual mounting of resistor devices. However, the above-mentioned LDS process requires that the raw materials be modified plastics containing organic metal compounds, which greatly restricts the selection of product materials, and the mechanical strength of the modified materials is also reduced compared to before modification. Laser micro-cladding and laser resistance trimming are both high-energy laser processing technologies. They require the substrate to be pre-coated with some relatively thin intermediate materials, and then the intermediate materials are struck with high-energy lasers to make the intermediate materials conductive and adhere to the substrate. In this process, the energy of the high-energy laser will penetrate the intermediate materials and affect the substrate itself, causing the substrate to become yellowed, carbonized, brittle, etc., and even due to the local high-energy input of the laser, the substrate material will experience a sharp rise in temperature, violent volatilization, and gasification, resulting in defects such as bubbling, wrinkles, and even falling off on the surface of the antenna structure. Manual placement of resistors is limited to small-batch operations in the laboratory. Once the product format is large and the number of resistors required is large, it will require a lot of manpower. Summary of the invention

[0004] In view of this, the present invention provides a curved antenna structure and a preparation method thereof to solve the problems of limited material selection and poor reliability of antenna and resistor structures in existing conformal antenna and resistor processing.

[0005] In a first aspect, the present invention provides a method for preparing a curved antenna structure, comprising:

[0006] Divide a plurality of areas to be processed on the surface of the curved substrate;

[0007] Obtaining surface height information of the area to be processed;

[0008] Divide the area to be processed into multiple fitting areas;

[0009] According to the acquired surface height information, a conductive metal paste is printed in a fitting area on the curved substrate to form an antenna unit; a plurality of antenna units are fitted to form an antenna pattern;

[0010] A resistance structure is formed between adjacent antenna patterns.

[0011] Beneficial effect: In the preparation method of the curved antenna structure of the present invention, the curved substrate to be printed is first divided into a plurality of areas to be processed before printing, and then the surface height information of each area to be processed is obtained, and then each area to be processed is again divided into a plurality of fitting areas, and then the conductive metal slurry is filled with a smaller fitting area as a basic unit according to the obtained surface height information to form an antenna unit, and a plurality of antenna units are fitted to form a single antenna pattern, and the plurality of antenna patterns are then connected by a resistance structure to form the final antenna radiation surface. Compared with large-area laser printing, which uses pre-coating of special intermediary materials to avoid damaging the substrate or enhancing adhesion, the present invention is aimed at fine printing of each fitting area, which can save intermediary materials and avoid damage to the substrate, and can achieve high conformality and reliable connection with the curved substrate, and is suitable for curved substrates of various high-performance materials, without the need to introduce laser processing means, thereby reducing the difficulty of preparation.

[0012] In an optional implementation, after dividing the surface of the curved substrate into a plurality of to-be-processed areas and before acquiring the surface height information of the to-be-processed areas, the method further includes:

[0013] Acquire height information of reference points of a plurality of to-be-processed areas arranged along a first preset direction on a curved substrate;

[0014] According to the obtained height information of the plurality of reference points, the Gaussian curvature of the curved surface base in the first preset direction is obtained.

[0015] Beneficial effect: By obtaining the heights of the reference points of multiple areas to be processed divided on the curved substrate in the first preset direction, the Gaussian curvature of the curved substrate in the first preset direction is obtained, and the curvature change of the curved substrate is further clarified, providing a basis for efficient fitting area division, and ultimately improving the preparation efficiency and quality of the curved antenna structure.

[0016] In an optional embodiment, when the Gaussian curvature of the curved base in a first preset direction is zero, obtaining the surface height information of the area to be processed includes: scanning the area to be processed along a second preset direction to obtain the surface height information of the area to be processed, and the second preset direction is perpendicular to the first preset direction.

[0017] Beneficial effect: Pre-acquiring that the Gaussian curvature of the curved surface base in the first preset direction is zero helps to simplify the acquisition of surface height information of the area to be processed, that is, the surface height information of the area to be processed can be scanned and acquired along the outer peripheral surface of the cylinder and in the second preset direction perpendicular to the axial direction of the columnar structure.

[0018] In an optional embodiment, the area to be processed is divided into multiple fitting areas, including: acquiring multiple first points along a second preset direction, dividing the area to be processed into multiple first fitting areas with the first point as the center, and the multiple first fitting areas are arranged in parallel along the second preset direction.

[0019] Beneficial effect: Within the scope of the area to be processed, first, multiple first points are acquired at intervals along the cylindrical surface of the curved base and in a direction perpendicular to the axial direction. Then, by diffusing with the first point as the center point, the area to be processed is divided into multiple strip-shaped first fitting areas arranged in sequence along the second preset direction. The division of the first fitting areas is simple and representative.

[0020] In an optional implementation, when the Gaussian curvature of the curved surface base in the first preset direction is not zero, obtaining the surface height information of the area to be processed includes:

[0021] Scan the area to be processed along a first preset direction to obtain first height information of the area to be processed; scan the area to be processed along a second preset direction to obtain second height information of the area to be processed, the second preset direction is perpendicular to the first preset direction, and the first height information and the second height information constitute surface height information of the area to be processed.

[0022] Beneficial effect: Height information is acquired from two perpendicular and orthogonal directions respectively, and height data of each point on the surface of the area to be processed is obtained, including the change trend from one point to the next point, which helps to realize accurate and efficient antenna unit processing in the area to be processed.

[0023] In an optional implementation, the area to be processed is divided into a plurality of fitting areas, including:

[0024] By means of cross-line scanning, a plurality of second points are selected from the origin along the first preset direction at intervals, and a plurality of third points are selected from the origin along the second preset direction at intervals;

[0025] Taking the obtained plurality of second sites and third sites as reference, a rectangular site array is formed;

[0026] The area to be processed is divided into a plurality of second fitting areas with the data points in the rectangular point array as the center.

[0027] Beneficial effect: The area to be processed is divided into a plurality of rectangular second fitting areas by diffusion with each data point in the rectangular point array as the center point. The plurality of rectangular second fitting areas are close to each other, which is more conducive to forming accurate filling and printing for the second fitting areas.

[0028] In an optional embodiment, a resistor structure is formed between adjacent antenna patterns, including: adjacent antenna patterns form a printing area at edges of a side close to each other; and a resistor structure is formed between the printing areas of adjacent antenna patterns by direct writing.

[0029] Beneficial effect: When a resistor structure is provided between adjacent antenna patterns, the edge portions of the antenna patterns are overlapped to achieve connection with the resistor structure, and the electrical interconnection is stable and reliable.

[0030] In an optional embodiment, the antenna pattern is made of conductive metal paste, and the resistance structure is made of graphite paste; after multiple antenna units are fitted to form the antenna pattern and before the resistance structure is formed between adjacent antenna patterns, it also includes: baking and curing the antenna pattern; after the resistance structure is formed between adjacent antenna patterns, it also includes: baking and curing the resistance structure.

[0031] Beneficial effect: The resistor structure uses graphite slurry, which has relatively weak conductivity and a curing temperature that is within the tolerable range of organic materials. After the slurry is printed on the curved substrate, the conductive metal slurry and graphite slurry are baked and cured to form an antenna pattern and the resistor structure has increased strength and reliability.

[0032] In an optional implementation, after forming the resistor structure between adjacent antenna patterns, the method further includes: spraying the surface of the curved substrate to encapsulate the antenna pattern and the resistor structure.

[0033] Beneficial effects: The spraying treatment forms an encapsulation protection for the antenna pattern and the resistor structure, preventing the antenna pattern and the resistor structure from being affected by oxidation, water vapor, etc. during long-term use, reducing the risk of resistance value changes of the resistor structure, and improving the long-term reliability of the product.

[0034] In a second aspect, the present invention also provides a curved antenna structure, which is manufactured using the above-mentioned method for preparing a curved antenna structure and is suitable for being set on a curved substrate, comprising: at least two antenna patterns and a resistor structure set between two adjacent antenna patterns, the curvature of the antenna pattern is equal to the curvature of the curved substrate, and the resistor structure is conductively connected to the antenna pattern.

[0035] Beneficial effects: The curved antenna structure includes an antenna pattern and a corresponding matching resistor structure that are integrally processed on a curved substrate. It does not need to be processed in sections through a variety of process equipment, has good consistency and good connection reliability with the curved substrate. It is suitable for being set on a curved substrate of a variety of high-performance materials, does not need to introduce laser processing methods, is simple to prepare, and can avoid damage to the curved substrate. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 is a flowchart of a method for preparing a curved antenna structure according to an embodiment of the present invention;

[0037] Figure 2 is a structural schematic diagram of a curved antenna structure according to an embodiment of the present invention;

[0038] Figure 3 is a schematic structural diagram of a curved substrate having zero curvature in a first preset direction according to an embodiment of the present invention;

[0039] Figure 4 is a schematic structural diagram of selecting a first point on a to-be-processed area according to an embodiment of the present invention;

[0040] Figure 5 is a schematic structural diagram of a region to be processed according to an embodiment of the present invention being divided into a plurality of first fitting regions;

[0041] Figure 6 is a schematic structural diagram of a curved substrate of an embodiment of the present invention having a non-zero curvature in a first preset direction;

[0042] Figure 7 is a schematic structural diagram of an embodiment of the present invention when a second point and a third point are selected on a region to be processed;

[0043] Figure 8 It is a structural schematic diagram of an embodiment of the present invention in which an area to be processed is divided into a plurality of second fitting areas.

[0044] 1. curved substrate; 2. area to be processed; 21. first point; 22. first fitting area; 23. second point; 24. third point; 25. second fitting area; 3. antenna pattern; 31. printing area; 4. resistor structure;

[0045] 100. Printing needle. DETAILED DESCRIPTION

[0046] The present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It is understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts of the present invention are shown in the accompanying drawings, not all structures. Various structural schematic diagrams according to embodiments of the present invention are shown in the accompanying drawings. These figures are not drawn to scale, and some details are magnified for the purpose of clear expression, and some details may be omitted. The shapes of various regions and layers shown in the figures and the relative sizes and positional relationships between them are only exemplary, and may deviate in practice due to manufacturing tolerances or technical limitations, and those skilled in the art may additionally design regions / layers with different shapes, sizes, and relative positions according to actual needs. In the context of the present invention, when a layer / element is referred to as being "on" another layer / element, the layer / element may be directly on the other layer / element, or there may be an intermediate layer / element between them. In addition, if a layer / element is "on" another layer / element in one orientation, then when the orientation is reversed, the layer / element may be "under" the other layer / element.

[0047] In the related technology, there are two main ways to make conformal antennas on the surface of curved structures: Laser Direct Structuring (LDS) and laser micro-cladding. The LDS process uses laser to directly transfer the circuit pattern to the surface of the plastic original. The modified plastic containing the organic metal complex is activated by laser to release metal particles and grow a metal seed layer, thereby forming a three-dimensional circuit structure, i.e., a conformal antenna, on the plastic surface. The laser micro-cladding process uses a high-power density laser beam to heat and melt the surface of the product pre-coated with a conductive material. The molten coating material cools rapidly and forms a microstructure with different properties to form a conformal antenna. There are two main ways to make resistors on the surface of curved structures: laser resistance trimming and manually mounted resistor devices. The laser resistance trimming process uses a short-pulse laser to process the surface of a product pre-coated with ruthenium or tungsten metal slurry, so that the resistor slurry layer is heated and vaporized by the laser to form a notch of a certain depth, thereby changing the conductive cross-sectional area and conductive length of the resistor body, and adjusting the resistor body with a resistance value lower than the target value to within the allowable deviation range of the resistance value; manually mounted resistors use manual soldering to mount resistor devices on the surfaces of some curved and special-shaped products.

[0048] The above-mentioned LDS process rigidly requires that the raw materials be modified plastics containing organic metal complexes. The selection of product materials is very limited, and it is impossible to make conformal antenna patterns on high-performance engineering insulating substrates such as polyimide (PI) and polyetheretherketone resin (PEEK); and after the raw materials are modified, the cost increases by 2 to 3 times, and the mechanical strength also decreases compared to before modification. Laser micro-cladding and laser resistance trimming are both high-energy laser processing technologies. The local heat input of laser processing is high, and the process control is very sensitive. It is not only easy to damage the plastic substrate, but also cause yellowing, carbonization, and brittleness of substrate materials such as PI and PEEK. At the same time, due to the characteristics of local high-energy input of lasers, the substrate material will also experience a sharp increase in temperature when irradiated by lasers, and violent volatilization and gasification, which will cause defects such as bubbling and wrinkles on the surface of the antenna structure. Manual placement of resistors is limited to small batch operations in the laboratory. Once the product format is large and the number of resistors required is large, it will require a lot of manpower, which is not conducive to mass production.

[0049] Based on the problems existing in the processing of conformal curved antenna structures, the present invention provides a method for preparing a curved antenna structure, abandoning the commonly used technical path of using laser processing means (such as the above-mentioned LDS, laser micro-cladding, laser resistance adjustment, etc.), by dividing the curved substrate into multiple tiny fitting areas, and then accurately printing antenna units in each fitting area according to the acquired surface height information, and finally forming an antenna pattern with high conformality to the curved substrate. Compared with conventional large-area direct laser forming with restrictions on substrate material selection and damage to substrate materials, the solution of the present invention avoids the restrictions on material selection and can form a high-precision conformal curved antenna structure without loss.

[0050] like Figures 1 to 8 As shown, this embodiment provides a method for preparing a curved antenna structure. Figure 1 The following is a flowchart of a method for preparing a curved antenna structure. The method comprises the following steps:

[0051] Step S101 : dividing a surface of a curved substrate 1 into a plurality of areas 2 to be processed.

[0052] For example, the curved substrate 1 is a 200 mm long curved product, the size of the area to be processed 2 is 1.6 mm*1.6 mm, and the spacing between the areas to be processed 2 is 1 mm.

[0053] Step S102, obtaining surface height information of the area to be processed 2.

[0054] In this embodiment, a displacement sensor is used to measure the height of the area to be processed 2, and the obtained surface height information of all the areas to be processed 2 is associated with the computer-aided manufacturing (Computer Aided Manufacturing, CAM for short) software.

[0055] Step S103, dividing the area to be processed 2 into a plurality of fitting areas.

[0056] Each area 2 to be processed is divided into a plurality of plane or inclined fitting areas, so as to perform accurate printing in each area 2 to be processed.

[0057] Step S104 , printing a conductive metal paste on a fitting area on the curved substrate 1 according to the acquired surface height information to form an antenna unit; a plurality of antenna units are fitted to form an antenna pattern 3 .

[0058] In this embodiment, according to the surface height information of the area to be processed 2, a direct writing printing method driven by precise air pressure is adopted to accurately extrude the conductive metal paste in each fitting area for filling and printing, so as to form an antenna unit with high conformality and reliable connection with the curved substrate 1, and multiple antenna units in multiple fitting areas finally constitute a single antenna pattern 3 in the area to be processed 2. Specifically, micro-nano ink direct writing printing equipment is used for printing, and a stainless steel printing needle 100 with an outer diameter of 310μm and an inner diameter of 150μm is selected, and the printing air inlet pressure is pre-set to 45psi and the printing speed is 10mm / s.

[0059] During printing, first install the print needle 100 and the barrel containing the conductive metal slurry into the micro-nano ink direct writing printing device, then move the print needle 100 to a fitting area of ​​the area to be processed 2 as the starting position, lower the print needle 100 so that the discharge end is 20 μm above the starting position, then turn on the printing air pressure, and the metal conductive slurry begins to be continuously extruded, filling and printing in turn according to the fitting area of ​​the plane or slope, completing the processing of all antenna units, and finally forming a complete antenna pattern 3.

[0060] Step S105 , forming a resistor structure 4 between adjacent antenna patterns 3 .

[0061] Exemplarily, a barrel containing the material of the resistor structure 4 is installed on the printing device, and the corresponding printing needle 100 is moved to the position where the resistor structure 4 needs to be formed; similarly, a stainless steel printing needle 100 with an outer diameter of 310μm and an inner diameter of 150μm is selected, and the printing air pressure is pre-set to 45psi and the printing speed is 10mm / s. During printing, the printing needle 100 drops to a position away from the edge of the antenna pattern 3, and the feed pressure is turned on 20μm above the surface of the antenna pattern 3. The antenna patterns 3 are linearly interconnected through the resistor structure 4, and multiple antenna patterns 3 are connected through the resistor structure 4 to form the final antenna radiation surface. Repeat the above printing action until all antenna patterns 3 are interconnected through the resistor structure 4.

[0062] Since the printing needle 100 needs to be brought close to the substrate surface during direct writing printing so that the printing paste contacts the printing substrate, in the scenario of conformal printing of curved surfaces, the fluctuation of the curvature of the curved substrate 1 will affect the printing line and even the printing quality. In view of this situation, in the preparation method of the curved antenna structure of this embodiment, before printing, the curved substrate 1 to be printed is first divided into a plurality of areas to be processed 2, and then the surface height information of each area to be processed 2 is obtained, and then each area to be processed 2 is again divided into a plurality of fitting areas, and then, according to the obtained surface height information, the conductive metal paste is filled with a smaller fitting area as a basic unit to form an antenna unit, and a plurality of antenna units are fitted to form a single antenna pattern 3, and the plurality of antenna patterns 3 are then connected through a resistor structure 4 to form the final antenna radiation surface. Compared with large-area laser printing, which uses special intermediary materials to avoid damaging the substrate or enhance adhesion, this solution uses fine printing for each fitting area. While saving intermediary materials to avoid damage to the substrate, it can also achieve high conformality and reliable connection with the curved substrate 1. It is suitable for curved substrates 1 made of various high-performance materials such as PI and PEEK. It does not require the introduction of laser processing methods, is simple to prepare, and can avoid damage to the curved substrate 1.

[0063] In this embodiment, after the surface of the curved substrate 1 is divided into a plurality of to-be-processed regions 2 in the above step S101 and before the surface height information of the to-be-processed regions 2 is acquired in the above step S102, the following steps are further included:

[0064] The height information of the reference points of a plurality of to-be-processed areas 2 arranged along a first preset direction on the curved substrate 1 is obtained.

[0065] Based on the influence of the curvature change of the curved substrate 1 on the printing line and printing quality in the curved surface conformal printing, the curvature change of the surface of the curved substrate 1 is measured in advance in this embodiment. For example, Figure 3 As shown, the first preset direction can be a horizontal direction along a partial surface of the curved base 1 or approximately equivalent to the axial direction, that is, the direction shown by the X-axis; a displacement sensor is used to measure the heights of multiple reference points of the to-be-processed area 2 along the first preset direction as the height information of the to-be-processed area 2. The reference point can be the center point of the to-be-processed area 2 or other representative points.

[0066] According to the obtained height information of the multiple reference points, the Gaussian curvature of the curved base 1 in the first preset direction is obtained.

[0067] Based on the data of multiple reference points, the Gaussian curvature of the curved surface base 1 in the first preset direction is calculated. Gaussian curvature is a quantity that describes the curvature of a surface, which represents the degree to which the surface is spherical, saddle-shaped, cylindrical or flat at a certain point; if a local coordinate system is taken on the surface, the Gaussian curvature of the point is determined by the ratio of the product of the radii of curvature in two mutually perpendicular directions. The above-mentioned first preset direction can be considered to be the same as one of the coordinate axes of the local coordinate system.

[0068] In this embodiment, by obtaining the reference point heights of multiple areas to be processed 2 divided on the curved base 1 in the first preset direction, the Gaussian curvature of the curved base 1 in the first preset direction is obtained, and the curvature change of the curved base 1 is further clarified, providing a basis for efficient fitting area division, and ultimately improving the preparation efficiency and quality of the curved antenna structure.

[0069] In one embodiment, when the Gaussian curvature of the curved substrate 1 in the first preset direction is zero, step S102, obtaining the surface height information of the area to be processed 2 includes: scanning the area to be processed 2 along a second preset direction to obtain the surface height information of the area to be processed 2, and the second preset direction is perpendicular to the first preset direction.

[0070] It should be known that a zero Gaussian curvature means that at least one of the principal curvatures of the surface is zero, that is, it is flat in at least one direction. For this embodiment, that is, the curved surface base 1 is flat in the first preset direction, as shown in FIG. Figure 3 On this basis, the acquisition of the surface height information of the area to be processed 2 can be simplified as follows: along the outer peripheral surface of the cylinder and in a second preset direction perpendicular to the axial direction of the columnar structure, the surface height information of the area to be processed 2 can be scanned and acquired.

[0071] Based on the above-mentioned scheme of zero Gaussian curvature, step S103 divides the area to be processed 2 into multiple fitting areas, including: obtaining multiple first points 21 along the second preset direction, dividing the area to be processed 2 into multiple first fitting areas 22 with the first point 21 as the center, and the multiple first fitting areas 22 are arranged in parallel along the second preset direction.

[0072] like Figure 4 and Figure 5 As shown, within a region 2 to be processed, along the cylindrical surface of the curved base 1 and in a direction perpendicular to the axial direction, multiple first points 21 are obtained at intervals. In this embodiment, five first points 21 are selected; then, the region 2 to be processed is divided into multiple strip-shaped first fitting regions 22 arranged in sequence along the second preset direction with the first point 21 as the center point. The multiple strip-shaped first fitting regions 22 are close to each other and any first fitting region 22 extends along the first preset direction. Figure 5 As shown, the first preset direction is the direction indicated by the X-axis, and the second preset direction is the direction indicated by the Y-axis.

[0073] In another embodiment, when the Gaussian curvature of the curved base 1 in the first preset direction is not zero, step S102, obtaining the surface height information of the area to be processed 2 includes: scanning the area to be processed 2 along the first preset direction to obtain the first height information of the area to be processed 2; scanning the area to be processed 2 along the second preset direction to obtain the second height information of the area to be processed 2, the second preset direction is perpendicular to the first preset direction, and the first height information and the second height information constitute the surface height information of the area to be processed 2.

[0074] Specifically, the Gaussian curvature of the curved substrate 1 in the first preset direction is not zero, which means that the curved substrate 1 is not flat in this direction. Corresponding to this embodiment, the surface of the curved substrate 1 is not flat only in the second preset direction perpendicular to the first preset direction, but also in the first preset direction. The first preset direction is Figure 6 The direction indicated by the X-axis is shown in the figure, and the second preset direction is Figure 6 The Y-axis direction is shown in . Therefore, the acquisition of the surface height information of the area to be processed 2 includes: scanning along the first preset direction on the periphery of the curved substrate 1 to obtain the first height information of the area to be processed 2, scanning along the second preset direction on the periphery of the curved substrate 1 to obtain the second height information of the area to be processed 2, and correspondingly integrating the first height information and the second height information to form the complete surface height information of the area to be processed 2. The height information is acquired from two perpendicular orthogonal directions respectively to obtain the height data of each point on the surface of the area to be processed 2, including the change trend from a certain point to the next point, so as to help realize accurate and efficient antenna unit processing in the area to be processed 2.

[0075] Based on the above solution in which the Gaussian curvature is not zero, step S103 divides the area to be processed 2 into a plurality of fitting areas, including:

[0076] By means of cross-line scanning, a plurality of second points 23 are selected at intervals along the first preset direction starting from the origin, and a plurality of third points 24 are selected at intervals along the second preset direction starting from the origin.

[0077] like Figure 7 and Figure 8As shown, the origin can be a point selected near the corner of the area to be processed 2, and multiple second sites 23 can be selected at equal intervals along the first preset direction, and multiple third sites 24 can be selected at equal intervals along the second preset direction. Of course, they can also be selected at unequal intervals according to the size and flatness of the area to be processed 2; in this embodiment, 5 second sites 23 and 5 third sites 24 are selected, and the second sites 23 and the third sites 24 close to the origin are set to coincide with the origin.

[0078] A rectangular site array is formed based on the obtained plurality of second sites 23 and third sites 24 .

[0079] It can be understood that Figure 8 In the coordinate system shown, 5 sites (including the origin) are selected along the X-axis and the Y-axis respectively, and then a corresponding rectangular site array is formed in the area of ​​the first quadrant based on the sites on the coordinate axis.

[0080] The area to be processed 2 is divided into a plurality of second fitting areas 25 with the data points in the rectangular point array as the center. That is, the area to be processed 2 is divided into a plurality of rectangular second fitting areas 25 with each data point in the rectangular point array as the center point diffusion, and the plurality of rectangular second fitting areas 25 are close to each other, such as Figure 8 shown.

[0081] The above-mentioned division of the to-be-processed area 2 into a plurality of rectangular second fitting areas 25 adjacent to each other is more conducive to forming accurate filling and printing for the second fitting areas 25 .

[0082] In one embodiment, in step S101, before dividing the surface of the curved substrate 1 into a plurality of areas 2 to be processed, it also includes: grabbing the optical positioning point of the curved substrate 1 and rotating the curved substrate 1. That is, firstly, the optical positioning point (also known as the Mark point) of the curved substrate 1 is visually grasped, and then the deflection angle of the curved substrate 1 is calculated according to the acquired Mark information, and the curved substrate 1 is rotated through a driving structure such as a direct drive motor. The basic principle of Mark point positioning is to select some specific points with high brightness, contrast and distinct morphological features on the curved substrate 1 to be measured, and after extracting the pixel information of these points through machine vision technology, calculate the position, angle, size and other information of these points to achieve accurate positioning of the position of the curved substrate 1 to be measured. The process of grabbing the optical positioning point and rotating and adjusting in this embodiment provides a common reference and measurable point for all subsequent measurement and processing steps, so that printing equipment and the like can accurately position the structure for processing.

[0083] In one embodiment, the step S105 of forming a resistor structure 4 between adjacent antenna patterns 3 includes: forming a printing area 31 at edges of adjacent antenna patterns 3 close to each other; and forming a resistor structure 4 between the printing areas 31 of adjacent antenna patterns 3 by direct writing.

[0084] In this embodiment, 200 μm is reserved at the edge of the antenna pattern 3 as an overlapping printing area 31, and then the printing device moves to this area to form a linear resistor structure 4 between two adjacent antenna patterns 3. Similarly, the printing needle 100 is about 20 μm away from the printing surface to extrude the material. When the resistor structure 4 is set between adjacent antenna patterns 3, the edge of the antenna pattern 3 is partially overlapped to achieve connection with the resistor structure 4, and the electrical interconnection is stable and reliable.

[0085] In one embodiment, the above-mentioned antenna pattern 3 is made of conductive metal paste, and the resistance structure 4 is made of graphite paste. After multiple antenna units are fitted to form the antenna pattern 3, and before the resistance structure 4 is formed between adjacent antenna patterns 3, it also includes: baking and curing the antenna pattern 3; and after the resistance structure 4 is formed between adjacent antenna patterns 3, it also includes: baking and curing the resistance structure 4.

[0086] The conductive metal paste in this embodiment is specifically selected as conductive silver paste, which has excellent conductive properties. Since conductive silver paste, conductive copper paste and other materials have excellent conductive properties, if they are directly used for the resistor interconnection of adjacent antennas, the resistance value of the resistor formed is very small and difficult to adjust later. Therefore, the resistor structure 4 of this embodiment uses graphite paste, which has relatively weak conductivity and a curing temperature within the range that organic materials can withstand. The viscosity of the conductive silver paste ranges from 100,000 cps to 600,000 cps, preferably 300,000 cps; the viscosity of the graphite paste used as the material of the resistor structure 4 ranges from 100,000 cps to 600,000 cps, preferably 100,000 cps. After the printing device prints the above-mentioned slurry onto the curved substrate 1, the above-mentioned conductive silver paste and graphite paste need to be baked and cured. The baking and curing temperature of the conductive silver paste is generally between 100°C and 250°C, and the baking time is 0.5 to 1h. The baking and curing of the conductive silver paste in this embodiment is preferably baked at 200°C for one hour; the baking and curing of the graphite paste is baked at 250°C for one hour. After the above-mentioned baking and curing, the strength and reliability of the antenna pattern 3 and the resistor structure 4 are increased.

[0087] In addition, this solution performs multiple measurements of resistance values ​​under different conditions for multiple resistor structures 4 of the same size, and the measurement results are shown in the following table:

[0088] Resistor Structure A Resistor Structure B Resistor Structure C Resistor Structure D Resistor Structure E width 300μm 300μm 300μm 300μm 300μm length 1000μm 1000μm 1000μm 1000μm 1000μm thickness 50μm 50μm 50μm 50μm 50μm Curing conditions 250℃20min 250℃25min 250℃30min 250℃40min 250℃60min Average resistance 213 181 155 153 153

[0089] It can be seen from the above table that the resistor structure 4 has a smaller resistance value when baked at 250° C. for 30 min to 60 min, and has excellent resistance performance.

[0090] In one embodiment, after forming the resistor structure 4 between adjacent antenna patterns 3 in the above step S105 , the process further includes: spraying the surface of the curved substrate 1 to encapsulate the antenna pattern 3 and the resistor structure 4 .

[0091] Specifically, after all the above-mentioned antenna patterns 3 and resistor structures 4 are processed, epoxy resin, three-proof paint and other materials are sprayed on the entire surface of the curved substrate 1 using a spray valve and other structures, and the sprayed materials are baked at 150°C for 30 minutes to form a package protection for the antenna pattern 3 and the resistor structure 4, to prevent the antenna pattern 3 and the resistor structure 4 from being affected by oxidation, water vapor and the like during long-term use, to reduce the risk of changes in the resistance value of the resistor structure 4, and to improve the long-term reliability of the product.

[0092] like Figure 2 As shown, this embodiment also provides a curved antenna structure, which is manufactured using the above-mentioned method for preparing the curved antenna structure. The curved antenna structure is suitable for being arranged on a curved substrate 1, and includes: at least two antenna patterns 3 and a resistor structure 4 arranged between two adjacent antenna patterns 3, the curvature of the antenna pattern 3 is equal to the curvature of the curved substrate 1, and the resistor structure 4 is conductively connected to the antenna pattern 3.

[0093] The above-mentioned curved antenna structure includes an antenna pattern 3 and a corresponding matching resistor structure 4 integrally processed on a curved substrate 1. It does not need to be processed in sections through a variety of process equipment, has good consistency and good connection reliability with the curved substrate 1, and is suitable for curved substrates 1 made of a variety of high-performance materials such as PI and PEEK. It does not need to introduce laser processing methods, is simple to prepare, and can avoid damage to the curved substrate 1.

[0094] In one embodiment, the curved antenna structure further includes a packaging layer covering the surface of the curved substrate 1 to cover and package the antenna pattern 3 and the resistor structure 4, so as to prevent the antenna pattern 3 and the resistor structure 4 from being affected by oxidation, water vapor, etc. during long-term use, reduce the risk of resistance value change of the resistor structure 4, and improve the long-term use reliability of the product. The further functional description of each of the above modules and units is the same as that of the above corresponding embodiments, and will not be repeated here.

[0095] Those skilled in the art will appreciate that, in order to form the same structure, those skilled in the art may also design methods that are not completely identical to the methods described above. In addition, although the various embodiments are described above, this does not mean that the measures in the various embodiments cannot be advantageously used in combination.

[0096] Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the present invention, and such modifications and variations are all within the scope defined by the appended claims.

Claims

1. A method for preparing a curved antenna structure, characterized in that: include: Divide a plurality of areas to be processed on the surface of the curved substrate; Acquiring surface height information of the area to be processed; Dividing the area to be processed into a plurality of fitting areas; Printing a conductive metal paste on the fitting area on the curved substrate according to the acquired surface height information to form an antenna unit; A plurality of the antenna units are fitted to form an antenna pattern; A resistor structure is formed between adjacent antenna patterns.

2. The method for preparing a curved antenna structure according to claim 1, characterized in that: After dividing the surface of the curved substrate into a plurality of to-be-processed areas and before acquiring the surface height information of the to-be-processed areas, the method further includes: Acquire height information of a plurality of reference points of the to-be-processed area arranged along a first preset direction on the curved substrate; The Gaussian curvature of the curved surface base in the first preset direction is obtained according to the obtained height information of the plurality of reference points.

3. The method for preparing a curved antenna structure according to claim 2, characterized in that: When the Gaussian curvature of the curved surface base in the first preset direction is zero, acquiring the surface height information of the area to be processed includes: The area to be processed is scanned along a second preset direction to obtain surface height information of the area to be processed, wherein the second preset direction is perpendicular to the first preset direction.

4. The method for preparing a curved antenna structure according to claim 3, characterized in that: The step of dividing the area to be processed into a plurality of fitting areas comprises: A plurality of first positions are acquired along the second preset direction, and the area to be processed is divided into a plurality of first fitting areas with the first positions as the center, and the plurality of first fitting areas are arranged in parallel along the second preset direction.

5. The method for preparing a curved antenna structure according to claim 2, characterized in that: When the Gaussian curvature of the curved surface base in the first preset direction is not zero, acquiring the surface height information of the area to be processed includes: Scan the area to be processed along the first preset direction to obtain first height information of the area to be processed; scan the area to be processed along the second preset direction to obtain second height information of the area to be processed, the second preset direction is perpendicular to the first preset direction, and the first height information and the second height information constitute surface height information of the area to be processed.

6. The method for preparing a curved antenna structure according to claim 5, characterized in that: The step of dividing the area to be processed into a plurality of fitting areas comprises: By means of cross-line scanning, a plurality of second positions are selected from the origin along the first preset direction at intervals, and a plurality of third positions are selected from the origin along the second preset direction at intervals; Taking the obtained plurality of second sites and the third sites as reference, forming a rectangular site array; The area to be processed is divided into a plurality of second fitting areas with the data sites in the rectangular site array as the center.

7. The method for preparing a curved antenna structure according to claim 1, characterized in that: The forming of a resistance structure between adjacent antenna patterns comprises: Adjacent antenna patterns form a printing area at edges of a side close to each other; and a resistance structure is formed between the printing areas of adjacent antenna patterns by direct writing printing.

8. The method for preparing a curved antenna structure according to claim 7, characterized in that: The antenna pattern is made of conductive metal slurry, and the resistor structure is made of graphite slurry; After the plurality of antenna units are fitted to form an antenna pattern and before a resistor structure is formed between adjacent antenna patterns, the method further includes: baking and curing the antenna pattern; After forming the resistance structure between the adjacent antenna patterns, the method further includes: baking and curing the resistance structure.

9. The method for preparing a curved antenna structure according to claim 1, characterized in that: After forming the resistor structure between the adjacent antenna patterns, the method further includes: spraying the surface of the curved substrate to encapsulate the antenna pattern and the resistor structure.

10. A curved antenna structure, characterized in that: The curved antenna structure is manufactured by the method for manufacturing the curved antenna structure according to any one of claims 1 to 9, and is suitable for being arranged on a curved substrate, comprising: at least two antenna patterns, wherein the curvature of the antenna patterns is equal to the curvature of the curved substrate; The resistor structure is arranged between two adjacent antenna patterns, and the resistor structure is conductively connected to the antenna patterns.

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