The present disclosure relates to a method for manufacturing an antenna structure, and an antenna structure.
Antennas are known in the art and used to convert radio frequency fields into alternating current or converting alternating current in to radio frequency. Antenna arrays with a set of two or more antenna elements are commonly used in various applications to combine or process signals from the antenna array in order to achieve improved performance over that of a single antenna element. For instance they are able to match a radiation pattern to a desired coverage area, changing radiation pattern, adapting to changing signal conditions and some configurations can cover a large bandwidth. Antenna arrays can be described by their radiation patterns and by the type of antenna elements in the system.
A conventional antenna structure comprises antenna elements on an antenna plate mounted to a circuit board. In such an arrangement, particularly in such an arrangement having active electronically scanned array (AESA), slot, notch or patch antennas operating at a high frequency, the available space for components limits the reachable frequency. A component which usually requires relatively large area on the circuit board is the fasteners (e.g. screws or bolts). The fasteners provide the function of allowing the circuit board and the antenna plate to achieve contact pressure so to have sufficient electrical contact, heat transfer as well as environmental robustness. Further, another component that usually requires a large area on a circuit board is the launch pin.
Further, when assembling an antenna plate with a plurality of antenna elements to a circuit board it is challenging to mount it properly in a rapid manner that doesn't hamper the robustness of the structure.
There is room for antenna structures to explore the domain of providing an antenna structure with an improved space efficiency, assembly, and an improved manufacturing convenience while maintaining a high environmental robustness. Further, such an improved antenna structure need to fulfil requirements relating to contact pressure between the antenna plate and the circuit board. There is specifically a lack in the present art of how to improve an antenna structure to obtain space efficiency on the circuit board of the structure while providing a simplified manufacturing, assembly and maintaining contact pressure requirements. Accordingly, there is room for improvements in the art to provide means for such an antenna structure.
Even though some currently known solutions work well in some situations it would be desirable to provide an antenna structure that fulfils requirements related to improving the manufacturing, assembly and space efficiency of an antenna structure.
It is therefore an object of the present disclosure to provide a method for manufacturing an antenna structure and an antenna structure to mitigate, alleviate or eliminate one or more of the above-identified deficiencies and disadvantages.
This object is achieved by means of a method for manufacturing an antenna structure and an antenna structure as defined in the appended claims.
The present disclosure is at least partly based on the insight that by providing a method for manufacturing an antenna structure and an antenna structure as such, the antenna structure will become more efficient and improved in terms of robustness, cost-efficiency, assembly and manufacturing.
In accordance with the disclosure there is provided a method and an antenna structure in accordance with the appended claims 1 and 14.
The present disclosure discloses a method for manufacturing an antenna structure, the method comprising the steps of: Providing an antenna plate and a sheet of dielectric comprising at least one electrical component on a first surface of said sheet of dielectric. Further, the method comprises the step of, by means of additive manufacturing, forming a metal plate, wherein the metal plate comprises a cavity structure. The formed metal plate further comprises a defined curvature around a central axis traversing a central portion of said metal plate. Moreover, the metal plate comprises an end angle, the end angle being based on an optimal contact-pressure in-between the at least one electrical component and a connecting surface of the antenna plate. Furthermore, the method comprises the steps of arranging the sheet of dielectric in-between the metal plate and the antenna plate and clamping first end portions of the metal plate to second end portions of the antenna plate, so to arrange the metal plate from a first curved state to a second flat state.
A benefit of the method is that it allows for the antenna structure and the metal plate to provide a uniform contact pressure between the sheet of dielectric and the cavity structure and/or the antenna structure without utilizing an excess amount of fastening elements. Thus, increasing the area on the sheet of dielectric, which is a requirement to unlock higher frequencies. Furthermore, by forming the metal plate by means of additive manufacturing a complex structure having cavities may beneficially be formed. Accordingly, the method utilizes additive manufacturing to form a complex metal plate having a curvature.
The metal plate may be a cooling plate having a first cooling surface and a second cooling surface, wherein the cavity structure is positioned intermediate the first and the second cooling surface, wherein the cavity structure is arranged to transfer a flow of cooling medium. Thus, by forming the cooling plate with a curvature allows for an efficient cooling of the sheet of dielectric, while providing sufficient pressure between the sheet of dielectric and the antenna plate. Accordingly, the present method provides for an antenna structure with a uniform contact pressure, over the sheet of dielectric while optimizing cooling of the sheet of dielectric.
The contact pressure may be in the range of 1-100 kPa.
Moreover, the end angle may in the range of 0.5-3.5 degrees. The end angle within said range may provide for a minimized curvature (so to reduce complexity when manufactured by additive manufacturing) of the metal plate but optimizing the contact pressure when the cooling plate is fully mounted.
The at least one electrical component may be a grounding pad. Accordingly, the clamped antenna structure allows for an electrical contact between the grounding pads on the sheet of dielectric and the antenna structure. This facilitates the operating of the antenna structure and further the contact pressure prevents any disharmony of the structure when being under vibrational motion.
The antenna plate may comprise a first elastic stiffness, wherein the metal plate comprises a second elastic stiffness, wherein the first stiffness is greater than the second stiffness.
A benefit of this is that it allows for the antenna plate to not deform, or to deform to a negligible amount, when the metal plate clamped to the antenna plate.
The first end portions of the metal plate and the second end portions of the antenna plate may be clamped by means of a fastening means such as bolts, screws or any other suitable fastening means.
The method may further comprise the step of, preceding forming the metal plate, design a three-dimensional computer aided design, 3D CAD model of the metal plate, import the 3D CAD model into an additive manufacturing, AM apparatus, wherein the 3D CAD model is designed so to provide an optimal end-angle and contact pressure when said metal plate is in said flat state.
The antenna plate may comprise a plurality of antenna elements being slot antenna elements, notch antenna elements, patch antenna elements or any other suitable type of antenna elements.
The method may further comprise the step of, preceding the step of clamping, a thermal interface sheet is arranged in-between the sheet of dielectric and the metal plate. A benefit of this is that it allows for the structure to handle different thicknesses of the sheet of dielectric, while maintaining a sufficient heat transfer.
The method may further comprise the step of press-fit mounting a launch pin in said through-hole via. The launch pin may comprise a conductive element and a dielectric element, wherein the conductive element comprises a first portion comprising a first diameter, the first portion extending towards a second portion comprising a second diameter, the second diameter being greater than the first diameter, wherein the dielectric element sleeves an upper part of the second portion of the conductive element, and wherein a lower part of the conductive element protrudes from an end portion of the dielectric element.
A benefit of this is that it allows for an improved space efficiency on the sheet of dielectric, the launch pin according to the present disclosure comprise a small footprint and is easy to manufacture and assemble. Resulting in an even further improved antenna structure with increased space on the sheet of dielectric for electronic components. This allows for said antenna structure to unlock higher frequencies.
Accordingly, during the step of arranging, the receiving section receives said launch pin. The receiving section may form a conical shape tapering towards the radiating section. Thus, allowing for easier arranging of the launch pin through the receiving section when the metal plate, antenna plate and sheet of dielectric is arranged together. The dielectric element may be circumferentially secured/enclosed to at least a part of the receiving section. Providing the benefit of allowing the dielectric element to be secured within the conical receiving section so to hold the launch pin attached.
There is also provided an antenna structure comprising an antenna plate, and a sheet of dielectric comprising at least one electrical component on a first surface of said sheet of dielectric. The antenna structure further comprises a metal plate formed by additive manufacturing, wherein the metal plate comprises a cavity structure. Moreover, the metal plate further comprises a first curved state and a second flat state. Furthermore, the sheet of dielectric is arranged in-between the metal plate and the antenna plate, wherein the metal plate is in said second flat state, wherein end portions of the metal plate are clamped to second end portions of the antenna plate.
The metal plate may be a cooling plate, thus the present antenna structure provides for sufficient cooling of the sheet of dielectric while also allowing for a space efficient structure.
The antenna plate may comprise a connecting surface facing the sheet of dielectric, the connecting surface may comprise a protruding rim associated with the receiving section wherein said protruding rim is in electrical contact with said grounding pad. The protruding rim may be formed as an extension of the receiving section. The protruding rim allows for a more convenient contact between the grounding pad and the antenna plate. The protruding rim combined with the attachment of the metal plate allows for a simplified mounting and improved contact pressure between the antenna plate and the grounding pad when mounted. Thus, providing an antenna structure being more robust and insensitive against vibrations and other disturbing means.
According to some embodiments, the lower part of the launch pin is attached to the sheet of dielectric by means of soldering from a back surface of the sheet of dielectric, the back surface being on an opposite side of the sheet of dielectric relative to the mounting surface.
Further, the dielectric element of the launch pin may comprise a third diameter, wherein the third diameter is 2-3 times greater than the first diameter, so to obtain a 50 ohm impedance.
The lower part of the conductive element may form an interference relative the through-hole via, so to allow press-fit mounting of the launch pin into the through-hole via.
In the following the disclosure will be described in a non-limiting way and in more detail with reference to exemplary embodiments illustrated in the enclosed drawings, in which:
In the following detailed description, some embodiments of the present disclosure will be described. However, it is to be understood that features of the different embodiments are exchangeable between the embodiments and may be combined in different ways, unless anything else is specifically indicated. Even though in the following description, numerous specific details are set forth to provide a more thorough understanding of the provided method and antenna structure, it will be apparent to one skilled in the art that the antenna structure and the method may be realized without these details. In other instances, well known constructions or functions are not described in detail, so as not to obscure the present disclosure.
The antenna structure 1 further comprises a metal plate 5 formed by additive manufacturing, wherein the metal plate 5 comprises a cavity structure 13 (see
By forming the metal plate 5 in a first curved state by means of additive manufacturing (3D printing), the metal plate 5 may have a complex inner structure while achieving the curved structure.
The antenna structure 1 in accordance with the present disclosure provides the benefit of allowing for a sufficient contact pressure between the electrical component and the sheet of dielectric 3 as well as reducing the need for excess fastening means 8 penetrating the antenna structure 1, metal plate 5 and the sheet of dielectric 3. The contact pressure may be in the range of 1-100 kPa. The contact pressure results in electrical contact between the electrical component 11 and the antenna plate 2 while also making the structure 1 less sensitive to vibrations.
A benefit of having the metal plate 5 in the form of a cooling plate is that, since the metal plate 5 is attached to a surface of the sheet of dielectric 3, it allows for it to be in vicinity to said sheet 3 resulting in less risk of overheating any electrical components 11 (i.e. a more efficient cooling) on the sheet of dielectric 3. Further, the metal plate 3 allows for the functioning as both a support structure for the antenna structure 1 and a cooling structure, fulfilling multiple functions. Consequently, the present disclosure provides a compact antenna structure 1 while maintaining performance.
As further shown in
The method 100 may further comprise the step of, prior to clamping 104, press-fit mounting a launch pin 20 into a through hole via 23 in the sheet of dielectric 3 (see launch pin in
It is illustrated in
A thermal interface sheet (see
The antenna plate 2 of the present disclosure may comprise a first elastic stiffness, wherein the metal plate 5 may comprise a second elastic stiffness, wherein the first stiffness is greater than the second stiffness. This prohibits the antenna plate 2 from deforming during the step of clamping 104 the metal plate 5 and the antenna plate 2.
The sheet of dielectric 3 and antenna plate 2 according to
The protruding rim 25 combined with the assembly provided by the first and second states of the metal plate 5 allows for an optimal electrical contact between the protruding rim 25 and the grounding pads 11 on the sheet of dielectric 3. Thus, the antenna structure 1 is robust and insensitive against vibrations and other disturbing means.
The launch pin 20 design allows it to be press-fitted into the through-hole via 23, this combined with the assembly of the metal plate 5 to the antenna plate 2 allows for an improved (more efficient) assembly of the antenna structure 1. Further, the launch pin 20 according to the present disclosure provides the benefit of having a small footprint. In other words, the launch pin 20 further improves the space efficiency on the sheet of dielectric 3. In accordance with the present disclosure, the sheet of dielectric 3 is improved in terms of space efficiency.
Further, the launch pin 20 comprising a conductive element 20″ formed with two portions 27, 28 with different dimensions allow for a launch pin 20 with less amount of components than a conventionally utilized launch pin 20. Thus, reducing the total amount of components on the antenna arrangement 1. Accordingly, the antenna arrangement 1 according to the present disclosure may significantly reduce the amount of components compared to conventional antenna arrangements, based on that the antenna arrangement 1 firstly, allows for a reduction of fastening means 8 and also reduction in components for the launch pin—this is achieved while simultaneously providing a more convenient structure to manufacture compared to conventional antenna structures.
According to some embodiments, the lower part 27″ of the launch pin 20 is attached to the sheet of dielectric 3 by means of soldering from a back surface 26 of the sheet of dielectric 3, the back surface 26 being on an opposite side of the sheet of dielectric 3 relative to the first surface 4.
Further, the dielectric element 20″ of the launch pin 20 comprises a third diameter, wherein the third diameter is 2-3 times greater than the first diameter, so to obtain a 50 ohm impedance.
The lower part of the conductive element 20′ may form an interference relative the through-hole via 23, so to allow press-fit mounting of the launch pin 20 into the through-hole via 23. Thus, “interference” means the diameter of the lower part of the conductive element 20′ is substantially equal to (or slightly smaller) than the through-hole via 23. Allowing the pin 20 to be fastened to the via 23.
Further, the receiving section 21 may be a conical receiving section (as seen in
Accordingly, the
Accordingly, during the step of arranging 103, the receiving section 21 receives said launch pin 20. The launch pin 20 may be inserted 101a by means of press-fit. Thus, the step 101a may be defined as press-fit mounting a launch pin 20 in said through-hole via 23.
It should be noted that the word “comprising” does not exclude the presence of other elements or steps than those listed and the words “a” or “an” preceding an element do not exclude the presence of a plurality of such elements. It should further be noted that any reference signs do not limit the scope of the claims, that the disclosure may be at least in part implemented by means of both hardware and software, and that several “means” or “units” may be represented by the same item of hardware.
Number | Date | Country | Kind |
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2100050-0 | Apr 2021 | SE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/SE2022/050368 | 4/13/2022 | WO |