Low-cost dielectric for power transmission and antenna using the same

Abstract

A transmission conduit for RF signals comprises: a dielectric board; a conductive circuit positioned on one surface of the dielectric board; a conductive ground positioned on the opposite surface of the dielectric board; wherein the dielectric board comprises a sandwich composed of at least one high dielectric constant layer and a foam board. The dielectric board can be made of a sandwich composed of glass and foam boards (for example). The glass boards and foam boards have thicknesses calculated to provide the sandwich with a desired total dielectric constant.

Description

Technical Field

[0001] The present disclosure relates generally to the field of dielectric materials for insulating electrical conductors. The disclosed dielectrics are particularly suitable for use in radio frequency transmission lines, such as lines for conducting radio frequency signals used by antennas. Background Art

[0002] Common methods of conducting electromagnetic energy between multiple locations are to use circuit boards with printed microstrip technology or metal waveguides. The advantage of circuit boards over waveguides is that they can be mass-produced and are flat. The disadvantage is that the loss is proportional to the distance the high-frequency electronic signal is transmitted. The advantage of metal waveguides is that they can operate with lower losses, but the disadvantage is that they are neither as thin as circuit boards nor as cost-effective.

[0003] Some circuit board substrates are designed to have low propagation losses. A typical low-loss substrate is a mixture of PTFE and glass. However, these boards are more expensive because of the extreme pressure required to press the PTFE and glass flat sheets.

[0004] Many low-loss materials (such as (commonly known as One problem with polytetrafluoroethylene (PTFE) is that the thermal expansion and contraction rates of these materials are very different from those of the conductive metal to which they would otherwise bond. For example, if a copper wire is formed on PTFE, the PTFE will expand at a different rate than the copper as the temperature changes and thus delaminate the copper. Current technology for addressing this expansion problem is to load the PTFE material with glass to reduce its coefficient of thermal expansion as well as a number of other processes.

[0005] Another problem with many low-loss materials such as polytetrafluoroethylene is that they have low surface energy, making them difficult to bond to conductive circuits. In many cases, glue or other adhesives are used, and these materials have negative RF propagation factors.

[0006] Another disadvantage of polytetrafluoroethylene is its high cost. In many modern applications, the entire transmission circuit needs to have a very low cost, which makes polytetrafluoroethylene prohibitively expensive.

[0007] It is a subsidiary of Evonik Degussa AG in Darmstadt, Germany. Structural foam based on polymethacrylimide (PMI) sold by Rohacell GmbH. The dielectric constant ε ris relatively low, ranging from about 1.046 to 1.093 depending on the specific formulation. Foams such as Rohacell have been used as dielectrics in RF systems, as exemplified in U.S. Publication No. 2015 / 0276459 entitled "Foam Filled Dielectric Rod Antenna."

[0008] Therefore, there is a need in the art for an improved transmission vehicle for electromagnetic energy, which may be used, for example, in an antenna for wireless communications. Summary of the invention

[0009] The following summary of the disclosure is included to provide a basic understanding of some aspects and features of the present invention. This summary is not an extensive overview of the present invention and, therefore, is not intended to specifically identify key or important elements of the present invention or to describe the scope of the present invention. Its sole purpose is to present some concepts of the present invention in a simplified form as a preface to the more detailed description presented below.

[0010] The disclosed embodiments provide a flat and low-cost dielectric material. In the disclosed examples, the embodiments are applied to antennas, but it can be applied to other devices requiring high-frequency electronic transmission, such as microwaves, radars, LIDARs, etc.

[0011] In the disclosed embodiments, the electrical conductors are separated by a dielectric material. The disclosed dielectric material can be used to replace any application that currently uses polytetrafluoroethylene as a replacement for polytetrafluoroethylene. Although polytetrafluoroethylene has high performance characteristics, it is relatively expensive. The disclosed embodiments can provide performance comparable to polytetrafluoroethylene, but at a much lower cost.

[0012] In general, dielectric panels are made from a sandwich of at least two sheets, one of which has a high dielectric constant, such as glass, and the other has a dielectric constant that is as close to that of air as possible. A good example of glass is glass, while good examples of materials with dielectric constants close to that of air are foams, such as structural foams, (e.g. ). The foam should have a dielectric constant of 1.0 to 1.1.

[0013] The disclosed embodiments include an antenna array having multiple radiating elements on a variable dielectric constant (VDC) material. The ability to vary the VDC provides control over the parameters of the antenna, including steering, using software. The dielectric layer separating the multiple elements of the antenna is implemented using a sandwich consisting of a glass sheet and a foam sheet. The ratio of the thickness of the glass to the thickness of the foam is calculated so that the dielectric constant experienced by the electric field is equal to the desired total dielectric constant. Specifically, the total dielectric constant can be increased by increasing the relative thickness of the glass compared to the foam, or can be reduced by reducing the relative thickness of the glass relative to the thickness of the foam.

[0014] Other embodiments provide non-radiating electrical devices having conductors separated by a dielectric sandwich composed of glass sheets and foam sheets.

[0015] The disclosed embodiments provide a transmission conduit for RF signals, comprising: a dielectric board; a conductive circuit positioned on one surface of the dielectric board; a conductive ground positioned on the opposite surface of the dielectric board; wherein the dielectric board comprises a sandwich consisting of at least one high dielectric constant layer and a foam board. The high dielectric constant layer is formed to have a dielectric constant of 3.8-4.4. The high dielectric constant layer may be formed of glass, PET, etc. The foam is formed to have a dielectric constant of 1.0 to 1.1. The dielectric board may be a foam board sandwiched between a top polyethylene terephthalate (PET) layer and a bottom PET layer. The conductive circuit may include at least one radiating patch or an electrical circuit defining a hybrid coupler.

[0016] In other embodiments, an antenna is provided, comprising: an insulating spacer; at least one radiating patch disposed on top of the insulating spacer; at least one delay line disposed below the insulating spacer; a variable dielectric constant (VDC) layer disposed below the delay line; a dielectric plate; a ground plane disposed below the dielectric plate; a bottom insulating plate disposed below the ground plane; and a feed line disposed below the bottom insulating plate; wherein at least one of the insulating spacer, the dielectric plate, and the bottom insulating plate comprises at least one high dielectric constant layer and a foam plate. The high dielectric constant layer may comprise one of: polytetrafluoroethylene, polyethylene terephthalate (PET), glass fiber impregnated polypropylene, or a glass plate. The high dielectric constant layer is formed to have a dielectric constant of 3.8-4.4. The foam is formed to have a dielectric constant of 1.0 to 1.1. The antenna may further comprise a conductive electrode adjacent to the VDC layer. At least one of the insulating spacer, the dielectric plate, and the bottom insulating plate may include a foam plate sandwiched between two glass plates or a foam plate sandwiched between two PET plates. The antenna may further include at least one conductive via connecting each of the delay lines to a corresponding radiating patch. The ground plane may include at least one window, each window being aligned below a corresponding one of the radiating patches.

[0017] According to other embodiments, a method for manufacturing an RF transmission conduit is provided, the method comprising: forming a conductive circuit on a top surface of an insulating plate, the insulating plate comprising one of a glass plate or polyethylene terephthalate (PET); attaching a ground plane to a bottom surface of a foam plate; adhering the insulating plate to the foam plate. Attaching the ground plane may comprise one of the following steps: forming the ground plane directly on the bottom surface of the foam plate; or forming the ground plane on a second insulating plate and adhering the second insulating plate to the bottom surface of the foam plate. The second insulating plate may be formed of one of a glass plate or polyethylene terephthalate (PET). BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Other aspects and features of the present invention will become apparent from the detailed description made with reference to the following drawings.It should be understood that the detailed description and drawings provide various non-limiting examples of various embodiments of the present invention, which are defined by the appended claims.

[0019] The accompanying drawings, which are incorporated in and constitute a part of this patent specification, illustrate embodiments of the present invention and, together with the description, are used to explain and illustrate the principles of the present invention. The accompanying drawings are intended to illustrate the main features of the exemplary embodiments in a diagrammatic manner. The accompanying drawings are not intended to depict every feature of the actual embodiments, nor are they intended to depict the relative sizes of the depicted elements, and the accompanying drawings are not drawn to scale.

[0020] FIG. 1 is a cross-section of a prior art structure utilizing a dielectric such as polytetrafluoroethylene.

[0021] Figure 2 An embodiment of a dielectric for a transmission device is shown.

[0022] Figure 3 A further embodiment of a transmission device is shown.

[0023] Figure 4A and Figure 4B An embodiment for a software controlled antenna utilizing the disclosed dielectric sandwich is shown.

[0024] Figure 5 Embodiments of non-radiative electronic devices utilizing the disclosed dielectric interlayer are shown.

[0025] Figure 6 A modified embodiment for an RF transmission catheter is shown. DETAILED DESCRIPTION

[0026] Embodiments of the dielectric sandwich of the present invention will now be described with reference to the accompanying drawings. Different embodiments or combinations thereof may be used for different applications or to obtain different benefits. Depending on the results sought to be obtained, the different features disclosed herein may be utilized partially or to the greatest extent, either alone or in combination with other features, thereby balancing the advantages with the requirements and constraints. Therefore, certain benefits will be emphasized with reference to different embodiments, but these benefits are not limited to the disclosed embodiments. That is, the features disclosed herein are not limited to the embodiments in which they are described, but may be "mixed and matched" with other features and combined in other embodiments.

[0027] FIG1 shows a cross section of a prior art device using polytetrafluoroethylene as a dielectric material 100. In this example, the dielectric constant of polytetrafluoroethylene is ε r =2.2, and its loss factor (loss tangent - ohmic loss) is tgδ = 0.0009. A ground conductor 105 is provided on the bottom of the dielectric 100, and a conducting and / or radiating electrode 110 (e.g. a microstrip line) is provided on the top of the dielectric 100. The thickness of the dielectric is denoted as h.

[0028] The open arrows in FIG. 1 show the resulting field. As shown in FIG. 1 , a portion of the field is transmitted only through the dielectric material, but some portion of the field is transmitted through both air and the dielectric material. Therefore, the effective dielectric constant is the average of the dielectric constant of air and the dielectric constant of polytetrafluoroethylene (or other dielectric material used). The effective dielectric constant is related to the square root of the product of the two dielectric constants weighted by the effective volume. Since in the view of FIG. 1 , the dielectric constant of air is 1, the effective dielectric constant of the structure of FIG. 1 is equal to the effective dielectric constant of polytetrafluoroethylene.

[0029] Figure 2 A general embodiment utilizing an innovative dielectric arrangement is shown. Figure 2 In the embodiment of the present invention, the dielectric sandwich 200 is made of two materials: a plate 202 with a high dielectric constant, such as polytetrafluoroethylene, polyethylene terephthalate (PET), glass fiber impregnated polypropylene or glass plate; and a plate made of a material with a dielectric constant close to that of air, such as a mostly air structural foam such as Rohacell 204. The ratio of the thickness of the two plates, h1 / h2, is calculated to obtain the desired effective dielectric constant. For example, in Figure 2 In the embodiment, you can use Glass. Vycor glass is a high silica glass sold by Corning and has a very low coefficient of thermal expansion. Depending on the recipe used for manufacturing, the dielectric constant of Vycor glass can be 3.8-4.4 and the loss factor is 0.0003. Plate 204 made of Rohacell has a dielectric constant of about 1.06 and a loss factor of 0.0003. Therefore, in this example, when the thickness of the two plates is made the same, that is, h1 / h2=1, the effective dielectric constant is ε r =2.159, and the effective loss factor (serial addition) is tgδ=0.0009.

[0030] from Figure 2 As can be seen in the examples of , the disclosed embodiments provide a dielectric that is composed of multiple layers of insulating materials adjacent to each other, resulting in a low-loss dielectric that can be tailored to have an effective dielectric similar to polytetrafluoroethylene. In one example, the top layer is made of a glass sheet. Figure 2 , an array of three radiating elements 210 is shown, although for clarity, the field lines of only one radiating element 210 are shown.

[0031] Figure 3 A cross section of another embodiment utilizing a multi-layer dielectric approach is shown. Figure 3The dielectric sandwich member 300 of the embodiment of the present invention is composed of three layers: a first glass plate 302, a second glass plate 303, and a space 306 filled with air. The plates 302 and 303 are kept spaced apart by a precise spacing h2 using spacers 308. A ground plate is formed on the bottom surface of the glass 303, while a transmission line or a radiating electrode is formed on the top surface of the glass 302. The thickness h1 of the glass plate 302 and the thickness h3 of the glass plate 303 are calculated separately so as to provide the required effective dielectric constant once the calculation is performed with the air layer 306 between them. In this case, if h1+h3=h2, that is, the thickness of the top glass plate plus the thickness of the bottom glass plate is equal to the air spacing, the effective dielectric constant is 2.09.

[0032] therefore, Figure 3 Embodiments provide a dielectric board made of two plates separated by a spacer to form an air gap between the two plates. Each plate can be made of glass (e.g., Vycor glass). In addition, the spacer can also be made of Vycor glass. The ground plate can be formed on one glass plate, and the wires of the radiating patch can be formed on the other glass plate.

[0033] Therefore, as can be understood, according to one aspect, a radiation device is provided, which includes: a dielectric board; a conductive ground plane formed on the bottom surface of the dielectric board; and a radiation element formed on the top surface of the dielectric board; wherein the dielectric board includes a glass board and a foam board.

[0034] Figure 4A-4B An example of a radiating device made using an innovative dielectric sandwich is shown. In U.S. Patent Application No. 15 / 654,643, the applicant discloses a multi-layer software defined antenna that utilizes a similar Figure 4A-4B The radiation device of the radiation device is an array of radiation devices, so this article will only repeat the relevant parts related to one radiation element. Figure 4B is Figure 4A A cross-section of the device is shown in top view of , which is an example showing a multi-layer software-defined antenna constructed using the dielectric interlayer disclosed in this article.

[0035] The radiation patch is represented as patch 410, and the delay line is represented as conductive line 415. The radiation patch formed on the top dielectric spacer 400 is usually in the form of a dielectric (insulating) board or dielectric sheet, but in this embodiment, is made of a dielectric sandwich member, which is composed of a glass board 402 and a foam board 404 (such as Rohacell). The radiation patch 410 is formed on the top surface of the glass by, for example, adhering a conductive film, sputtering, printing, etc. At the patch location, a via 425 is formed in the glass 402 and the foam 404, and a conductor is passed through the via and connected to the back side of the patch 410. The delay line 415 is formed on the bottom surface of the foam board 404 (or the top surface of the upper adhesive 442) and is physically and electrically connected to the conductor in the via 425. That is, there is a continuous DC connection from the delay line 415 through the conductor in the via 425 to the radiation patch 410. As Figure 4A As shown in FIG. 4 , the delay line 415 is a meandering wire and may have any shape to have sufficient length to produce the desired delay to induce the desired phase shift in the RF signal.

[0036] The delay in delay line 415 is controlled by a variable dielectric constant (VDC) plate 440 having a variable dielectric constant material 444. Although any manner of constructing VDC plate 440 may be suitable for use with embodiments of the antenna, in a specific embodiment, as a matter of simplicity, a VDC plate 440 is shown that is composed of an upper adhesive 442 (e.g., glass, PET, etc.), a variable dielectric constant material 444 (e.g., a twisted nematic liquid crystal layer), and a bottom adhesive 446. In other embodiments, one or both of adhesive layers 442 and 444 may be omitted. Alternatively, an adhesive such as epoxy or glass beads may be used in place of adhesive layers 442 and / or 444. Likewise, as shown in FIG. Figure 4B As shown in , according to the embodiments disclosed herein, one or both of the adhesives can be constructed as a sandwich. As an example, the bottom adhesive 446 is shown as a two-layer sandwich with a foam board 448 and a glass board 449.

[0037] In some embodiments, for example, when a twisted nematic liquid crystal layer is used, the VDC plate 440 further includes an alignment layer that may be deposited and / or glued to the bottom of the upper adhesive 442. The alignment layer may be a thin layer of material (e.g., polyimide-based PVA) that is rubbed or cured using ultraviolet (UV) radiation in order to align the LC molecules at the edge of the confining substrate.

[0038] The effective dielectric constant of the VDC plate 440 can be controlled by applying a DC potential across the VDC plate 440. To this end, electrodes are formed and connected to a controllable voltage potential. There are a variety of arrangements for forming the electrodes, and several examples will be shown in the disclosed embodiments. Figure 4B In the arrangement shown in , two electrodes 443 and 447 are provided - one is provided on the bottom surface of the upper adhesive 442 and one is provided on the upper surface of the bottom adhesive 446. As an example, electrode 447 is shown, which is connected to the variable voltage potential 441, while electrode 443 is grounded. As an alternative, as shown in dashed lines, electrode 443 can also be connected to variable potential 439.

[0039] Thus, by changing the output voltage of the variable potential 441 and / or the variable potential 439, the dielectric constant of the VDC material near the electrodes 443 and 447 can be changed, and thereby the RF signal transmitted on the delay line 415 can be changed. Changing the output voltage of the variable potential 441 and / or the variable potential 439 can be achieved using a controller, Ctl, running software, which causes the controller to output appropriate control signals to set the appropriate output voltage of the variable potential 441 and / or the variable potential 439. Likewise, a conventional controller can be used to provide control signals and common signals to control the characteristics of the antenna. Thus, the performance and characteristics of the antenna can be controlled using software - thereby obtaining a software-controlled antenna.

[0040] At this point, it should be clarified that in this description, the use of the term "ground" refers to both a generally acceptable ground potential (i.e., ground potential) and a common or reference potential, which can be a set potential or a floating potential. For example, a conventional LCD display controller outputs two signals per pixel, one of which is referred to as a ground or common signal. Similarly, although a symbol for grounding is used in the accompanying drawings, it is used as a simplification to represent grounding or common potentials interchangeably. Therefore, whenever the term "grounding" is used in this document, the term common or reference potential (which can be a set or floating potential) is included therein.

[0041] In the transmit mode, the RF signal is applied to the feed patch 460 via the connector 465 (e.g., a coaxial cable connector). Figure 4B As shown in FIG. 4 , there is no electrical DC connection between the feed patch 460 and the delay line 415. However, in the disclosed embodiment, the layers are designed so as to provide an RF short circuit between the feed patch 460 and the delay line 415. Figure 4BAs shown in , a backplane conductive ground (or common end) 455 is formed on the top surface of the backplane insulator (or dielectric) 450 or the bottom surface of the bottom adhesive 446. The backplane conductive ground 455 is typically a conductor layer that covers the entire area of ​​the antenna array. At each RF feed position, a window (DC breaker) 453 is set in the backplane conductive ground 455. The RF signal is transmitted from the feed patch 460 via the window 453 and is coupled to the delay line 415. Reverse occurs during reception. Therefore, a DC disconnection and an RF short circuit are formed between the delay line 415 and the feed patch 460. The backplane insulator 450 can also be constructed according to the embodiments disclosed herein. In this example, the backplane insulator 450 includes a glass plate 452, a foam plate 454 and a glass plate 456.

[0042] Therefore, as can be understood, according to one aspect, a radiation device is provided, which includes: a dielectric board; a radiation element formed on the top surface of the dielectric board; a dielectric backplane; a conductive ground plane formed on the bottom surface of the dielectric backplane; a variable dielectric constant material sandwiched between the dielectric board and the dielectric backplane; wherein at least one of the dielectric board and the dielectric backplane includes a glass plate and a foam plate.

[0043] As shown thus far, the embodiments disclosed herein may be used for radiating elements, such as antennas and antenna arrays. However, according to aspects of the present invention, electronic devices or components may also be provided that have variable electrical characteristics or operation based on a potential applied to a variable dielectric constant sector associated with the device, and that incorporate low-cost dielectric interlayer components. According to aspects of the present invention, electronic devices or components may include elbows, power dividers, filters, ports, phase shifters, frequency shifters, attenuators, couplers, capacitors, inductors, antenna duplexers, bridged forks (hybrids) of beamforming networks, and in addition to electronic devices, may also include radiating elements. It is worth noting that, just as in the use of As is done in the prior art of PCP, several devices can be formed on the same dielectric interlayer.

[0044] According to the disclosed aspects, the electronic device disclosed in applicant's US Patent Application No. 5,434,866 may be modified using an interlayer dielectric board, thereby providing the same performance at a much lower cost. Figure 5 An embodiment of a four-port hybrid coupler 500 is shown. In the absence of any VDC, the signal input at port 1 is split into an output to port 2 with no phase change and an output to port 3 with a 90 degree phase change. Similarly, the signal input to port 4 is split into an output to port 3 with no phase change and an output to port 2 with a 90 degree phase change. This is explained by Figure 5However, in Figure 5 In the embodiment of FIG. 5 , several optional placements for the VDC are shown, all or part of which may be implemented depending on the desired control over the operation of the hybrid coupler 500 .

[0045] For example, VDC 503 is provided below the line of input port 1. By applying a voltage potential to the electrodes of VDC 503, the phase of the input signal can be controlled. Therefore, the phases at output ports 2 and 3 will be changed together based on the phase change caused by the voltage potential at VDC 503. This means that the phase at output 2 may be different from the phase of the input signal at input port 1. On the other hand, the phase at output 2 can be changed alone by the voltage potential at VDC 507. Therefore, the phase at output port 3 will remain 90° relative to the input at input port 1, but the phase at output port 2 will be different from zero according to the voltage potential applied to VDC 507. In addition, a voltage potential can be applied to the electrodes of VDC 527 to change the phase at output port 3 in a manner independent of the output at port 2. Therefore, the output at port 2 can remain in the same phase as the input at port 1, but the output at port 3 can be changed by 90° relative to the input at port 1. The same effect can be applied to the input of input port 4 by applying voltage potentials to VDC 523, 507 and 527. Again, normally an input signal at port 1 will be split with equal energy between output ports 2 and 3. However, by controlling the voltage potentials at VDC 508, 528, 515A and 515B, the amount of energy delivered to each output port can be altered, and therefore the amplitude of the output at each port can be controlled.

[0046] exist Figure 5 You can see the illustration number Figure 5 . Element 527 is a variable dielectric constant material that receives a potential from a power source V. Wire 520 is formed on top of a dielectric plate 550, which can be made according to any of the embodiments disclosed herein. For example, it can be made by a sandwich consisting of a glass plate and a foam plate. The same is true for back plate 555, which can also be made according to any of the embodiments disclosed herein. For example, it can be made by a sandwich consisting of a glass plate and a foam plate.

[0047] Therefore, as can be understood, according to one aspect, an electronic device is provided, comprising: a backplate; a dielectric plate; a variable dielectric constant material sandwiched between the backplate and the dielectric plate; an electrode configured to apply an electric potential to the variable dielectric constant material; and a wire formed on top of the dielectric plate; wherein at least one of the dielectric plate and the backplate comprises a glass plate and a foam plate.

[0048] Figure 6 A variant embodiment for an RF transmission conduit is shown, which may be radiating, non-radiating, or both, such as a non-radiating transmission line leading to a radiating patch. Figure 6 In the embodiment of FIG. 6 , the dielectric sandwich 600 is made of two materials: a top layer of PET (polyethylene terephthalate) 607 having a high dielectric constant; a board of material having a dielectric constant close to that of air, such as structural foam 604 (e.g., Rohacell) which is mostly air; and a bottom layer of PET 608. The ratio of the thickness of the two PET layers and the thickness of the foam board (h1+h3) / h2 is calculated to obtain the desired effective dielectric constant. For example, in Figure 6 In the example of , a PET layer is used that has a dielectric constant of about 4.0 at 3 GHz. Depending on the recipe used to make the PET, it may have a slightly different dielectric constant, but it is in the range of 3.8-4.4.

[0049] exist Figure 6 In the example of , a wire or patch 610 is made on the top surface of PET 607. A conductive ground plane 605 is made on the bottom surface of PET 608. The PET layer is then adhered to the foam core 604. This makes it very easy to manufacture because it is very easy to manufacture the wire 610 and the conductive ground plane 605 on PET using a variety of techniques such as printing, sputtering, plating, etc. In addition, the conductive circuits 610 and 605 can be easily manufactured using a reel-to-reel method, which is fast and economical.

[0050] As with all RF antennas, reception and transmission are symmetrical, so that a description of one applies equally to the other. In this description, it may be easier to explain transmission, but reception will be the same, just in the opposite direction.

[0051] It should be understood that the processes and techniques described herein are not inherently related to any specific equipment and can be implemented by any applicable combination of parts. In addition, according to the teachings described herein, various types of general devices can be used. The present invention has been described with respect to specific examples, which are intended to be illustrative rather than restrictive in all respects. It will be appreciated by those skilled in the art that many different combinations will be applicable to practice the present invention.

[0052] In addition, by considering the patent specification and practice of the invention disclosed herein, other embodiments of the present invention will be apparent to those skilled in the art. Aspects and / or components of the embodiments described may be used alone or in any combination. It is intended that the patent specification and examples be considered exemplary only, and the true scope and spirit of the present invention are represented by the appended claims.

Claims

1. An antenna, comprising: Dielectric board; at least one radiating patch disposed on top of the dielectric board; at least one delay line, the at least one delay line being disposed below the dielectric plate; Wherein, the dielectric plate comprises at least one high dielectric constant layer and a foam plate adjacent to each other with a dielectric constant of 3.8-4.4; a variable dielectric constant layer, the variable dielectric constant layer being disposed below the delay line; a ground plane disposed below the variable dielectric constant layer; a bottom insulating plate disposed below the ground plane; and a feeder line disposed below the bottom insulating plate; Wherein, the bottom insulating plate includes at least one high dielectric constant layer with a dielectric constant of 3.8-4.4 and a foam plate.

2. The antenna according to claim 1, wherein: The high dielectric constant layer is formed of glass.

3. The antenna according to claim 1, wherein: The high dielectric constant layer is formed of polyethylene terephthalate.

4. The antenna according to claim 1, wherein: The foam sheet is formed to have a dielectric constant of 1.0 to 1.

1.

5. The antenna according to claim 1, wherein: The dielectric sheet includes a foam sheet sandwiched between top and bottom polyethylene terephthalate layers.

6. The antenna according to claim 1, wherein: The variable dielectric constant layer of the antenna further includes at least one of an upper adhesive and a bottom adhesive.

7. The antenna according to claim 6, wherein: The at least one of the upper adhesive and the bottom adhesive includes at least one high dielectric constant layer and a foam sheet.

8. The antenna according to claim 1, wherein: The antenna also includes a conductive electrode adjacent to the variable dielectric constant layer.

9. The antenna according to claim 1, wherein: The bottom insulating panel includes a foam panel sandwiched between two glass panels.

10. The antenna according to claim 1, wherein: The bottom insulating board includes a foam board sandwiched between two polyethylene terephthalate boards.

11. The antenna according to claim 1, wherein: The antenna also includes at least one conductive via connecting each of the delay lines to a corresponding radiating patch.

12. The antenna according to claim 1, wherein: The ground plane includes at least one window, each window being aligned beneath a respective one of the radiating patches.

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