Manufacturing method of cylindrical Luneburg lens and Luneburg lens antenna

Abstract

The present invention relates to a manufacturing method of a cylindrical Luneburg lens and a Luneburg lens antenna. The method is used to manufacture a cylindrical Luneburg lens, and the cylindrical Luneburg lens includes a plurality of layers of annular lenses sequentially arranged from inside to outside along the radial direction. The method includes: obtaining the initial radius and initial thickness of each annular lens, and respectively determining the target radius and target thickness of each annular lens; the target radius and target thickness are obtained by normalizing the initial radius and initial thickness; based on each initial radius and each initial thickness, determining the dielectric constant value of each annular lens; according to each dielectric constant value, each target radius and each target thickness, transmitting a printing instruction to a 3D printer; the printing instruction is used to instruct the 3D printer to print the cylindrical Luneburg lens. The present application can manufacture a low-profile cylindrical Luneburg lens by means of 3D printing, provides a simple and feasible manufacturing method for a deformed Luneburg lens, and further reduces the manufacturing difficulty of the Luneburg lens.

Description

Technical Field

[0001] The present invention relates to the field of communication technologies, and particularly to a manufacturing method of a cylindrical Luneburg lens and a Luneburg lens antenna. Background Art

[0002] With the rapid development of radio frequency technologies, electromagnetic field and electromagnetic wave theories, radio devices have played a significant role in human society. Among them, as the transmitting and receiving ends of electromagnetic waves in a radio system, the performance of an antenna will have a decisive impact on the overall performance of the radio system. With the expansion of radio frequency technologies to ultra-high frequencies and extremely high frequencies, and the development and utilization of spectrum resources, millimeter waves have shown great advantages and application scenarios. Among them, the working wavelength of millimeter waves is in the overlapping wavelength range between microwaves and far-infrared waves, and its frequency range is from 30 GHz to 300 GHz, thus having the characteristics of both types of waves at the same time. Currently, the application fields of millimeter waves include wireless communication, satellite communication, radar systems, radio frequency identification, electromagnetic interference, etc., and it has outstanding advantages in 5G communication and civil automotive anti-collision radars, etc.

[0003] The Luneburg lens exhibits excellent broadband characteristics, fast beam switching ability, wide-angle scanning ability, beam focusing ability, and high-speed data transmission ability, showing absolute advantages in the millimeter-wave frequency range, and thus can be widely applied to the above-mentioned multiple fields. However, the inventor has found that traditional Luneburg lenses have the problem of complex preparation processes. Summary of the Invention

[0004] Based on this, it is necessary to provide a simple and feasible manufacturing method of a cylindrical Luneburg lens and a Luneburg lens antenna for the problem of complex manufacturing processes existing in traditional technologies.

[0005] To achieve the above object, on the one hand, an embodiment of the present application provides a manufacturing method of a cylindrical Luneburg lens, which is used to manufacture a cylindrical Luneburg lens. The cylindrical Luneburg lens includes a plurality of layers of annular lenses sequentially arranged from inside to outside in the radial direction. The method includes: obtaining the initial radius and initial thickness of each annular lens, and respectively determining the target radius and target thickness of each annular lens; wherein, the target radius and target thickness are obtained by normalizing the initial radius and initial thickness; determining the dielectric constant value of each annular lens based on each initial radius and each initial thickness; transmitting a printing instruction to a 3D printer according to each dielectric constant value, each target radius, and each target thickness; wherein, the printing instruction is used to instruct the 3D printer to print the cylindrical Luneburg lens.

[0006] In one embodiment, the step of determining the dielectric constant values of the annular lenses based on the respective initial radii and initial thicknesses includes: processing the respective initial radii and initial thicknesses by using the quasi-conformal transformation theory and Maxwell's equations to obtain the relative dielectric constant distribution function of the cylindrical Luneburg lens; determining the dielectric constant values of the annular lenses according to the relative dielectric constant distribution function; wherein, the ratio of the dielectric constant values of two adjacent layers of annular lenses is a fixed value.

[0007] In one embodiment, the step of separately determining the target radii and target thicknesses of the annular lenses includes:

[0008] Determining the radius value range of the present layer of annular lens according to the initial radius corresponding to the present layer of annular lens, and determining the thickness value range of the present layer of annular lens according to the initial thickness corresponding to the present layer of annular lens; processing the radius value range and the thickness value range by using the Green's function and the electromagnetic field superposition algorithm to obtain the normalized outer radius of the present layer of annular lens; determining the target radius and target thickness of the present layer of annular lens according to the normalized outer radius.

[0009] In one embodiment, the step of obtaining the initial radii and initial thicknesses of the annular lenses includes: deforming the antenna parameters of the ideal Luneburg lens by using the transformation optics theory to obtain the initial radii and initial thicknesses.

[0010] In one embodiment, the printing instruction is used to instruct a 3D printer to manufacture a cylindrical Luneburg lens by multiple single-layer printing.

[0011] On the other hand, an embodiment of the present application provides a Luneburg lens antenna, including a cylindrical Luneburg lens. The cylindrical Luneburg lens includes a plurality of layers of annular lenses arranged in sequence from the inside to the outside in the radial direction, and is prepared by using the above manufacturing method.

[0012] In one embodiment, the dielectric constant values of the annular lenses are different from each other and decrease in sequence from the inside to the outside, and the ratio of the dielectric constant values of two adjacent layers of annular lenses is a fixed value.

[0013] In one embodiment, the Luneburg lens antenna further includes a feed source, and the feed source is arranged on the outermost layer of the annular lens.

[0014] In one embodiment, the number of the annular lenses is 5 layers.

[0015] In one embodiment, the thicknesses of the annular lenses are different from each other.

[0016] In the above method for manufacturing a cylindrical Luneburg lens and a Luneburg lens antenna, the cylindrical Luneburg lens includes several layers of annular lenses arranged successively from the inside to the outside in the radial direction. By obtaining the initial radius and initial thickness of each annular lens, and respectively determining the target radius and target thickness of each annular lens, where the target radius and the target thickness are obtained by normalizing the initial radius and the initial thickness; and based on each of the initial radii and each of the initial thicknesses, determining the dielectric constant value of each annular lens; according to each of the dielectric constant values, each of the target radii and each of the target thicknesses, transmitting a printing instruction to a 3D printer; the printing instruction is used to instruct the 3D printer to print the cylindrical Luneburg lens, so that a low-profile cylindrical Luneburg lens can be manufactured by a 3D printing method, providing a simple and feasible method for manufacturing a deformed Luneburg lens, thereby reducing the manufacturing difficulty of the Luneburg lens. Description of the Drawings

[0017] In order to more clearly illustrate the technical solutions in the embodiments of the present application or in the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0018] Figure 1 It is a schematic flowchart of a method for manufacturing a cylindrical Luneburg lens in an embodiment;

[0019] Figure 2 It is a schematic flowchart of determining the target radius and target thickness in an embodiment;

[0020] Figure 3 It is a schematic flowchart of determining the dielectric constant value of each annular lens in an embodiment;

[0021] Figure 4 It is a first schematic structural diagram of a Luneburg lens antenna in an embodiment;

[0022] Figure 5 It is a second schematic structural diagram of a Luneburg lens antenna in an embodiment;

[0023] Description of the Reference Numerals:

[0024] 410 - First annular lens, 412 - Second annular lens, 414 - Third annular lens, 416 - Fourth annular lens, 418 - Fifth annular lens, 420 - Feeder, 422 - Metal sheet. Detailed Embodiments

[0025] To make the above objects, features, and advantages of the present invention more apparent and understandable, the following detailed description of the specific embodiments of the present invention will be given with reference to the accompanying drawings. Many specific details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can be implemented in many other ways different from those described herein, and those skilled in the art can make similar improvements without departing from the spirit of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0026] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. These are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0027] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically and clearly defined.

[0028] In the present invention, unless otherwise clearly specified and limited, the terms "mounted", "connected", "coupled", "fixed", etc. should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0029] In the present invention, unless otherwise clearly specified and limited, the first feature being "on" or "under" the second feature can be that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over", and "on top of" the second feature can be that the first feature is directly above or obliquely above the second feature, or simply means that the first feature has a higher horizontal height than the second feature. The first feature being "below", "beneath", and "underneath" the second feature can be that the first feature is directly below or obliquely below the second feature, or simply means that the first feature has a lower horizontal height than the second feature.

[0030] It should be noted that when an element is referred to as "fixed to" or "disposed on" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time. The terms "vertical", "horizontal", "upper", "lower", "left", "right" and similar expressions used herein are for illustrative purposes only and do not represent the only implementation.

[0031] As used herein, the singular forms "a", "an" and "the" may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms "comprising" or "having" and the like specify the presence of the stated features, wholes, steps, operations, components, parts or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, wholes, steps, operations, components, parts or combinations thereof. At the same time, the term "and / or" used in this specification includes any and all combinations of the related listed items.

[0032] As described in the background, traditional Luneburg lenses have the problem of complex preparation processes. In addition, traditional Luneburg lenses also have disadvantages such as difficult material preparation, complex structures, and large volumes. All of the above-mentioned disadvantages limit the further application of Luneburg lenses in the millimeter-wave band, resulting in their inability to be popularized and promoted on a large scale. Based on this, it is necessary to provide a simple and feasible method for manufacturing a deformed Luneburg lens layer by layer and a manufacturing method to solve problems such as difficult engineering implementation of electromagnetic characteristics and complex preparation processes of Luneburg lenses. In some embodiments, a novel low-profile Luneburg lens antenna is also provided, which has the advantage of a simple structure. Further, the Luneburg lens antenna can also be applied to millimeter-wave communication and can achieve high gain, low sidelobe level, and miniaturization.

[0033] In one embodiment, please refer to Figure 1 , Figure 1 shows a manufacturing method of a cylindrical Luneburg lens for manufacturing a cylindrical Luneburg lens, which includes a plurality of layers of annular lenses arranged in sequence from the inside to the outside in the radial direction. The specific number of annular lenses can be determined according to the specific parameters of the Luneburg lens or antenna parameters, etc., and the present application does not make specific limitations in this regard. For ease of understanding, the following will take 5 layers of annular lenses as an example for illustration. The manufacturing method specifically includes the following steps:

[0034] Step S110, obtain the initial radius and initial thickness of each annular lens, and respectively determine the target radius and target thickness of each annular lens; the target radius and target thickness are obtained by normalizing the initial radius and initial thickness.

[0035] Among them, each layer of annular lens can respectively correspond to the corresponding initial radius, initial thickness, target radius, and target thickness. The initial radii, initial thicknesses, target radii, and target thicknesses can be different from each other. The initial radius can be a value obtained by transforming an ideal Luneburg lens and used to estimate the target radius of the annular lens; the initial thickness can be a value obtained by transforming an ideal Luneburg lens and used to estimate the target thickness of the annular lens. The initial radius and target radius of the same layer of annular lens can be the same or different. Similarly, the initial thickness and target thickness of the same layer of annular lens can be the same or different. The target radius is the radius value of the annular lens when manufacturing a cylindrical Luneburg lens; the target thickness is the thickness value of the annular lens when manufacturing a cylindrical Luneburg lens. Further, the initial thickness can be determined according to the respective initial radii, and the target thickness can be determined according to the respective target radii.

[0036] Specifically, the initial radius and initial thickness corresponding to each layer of annular lens are obtained respectively. In one embodiment, the steps of obtaining the initial radius and initial thickness of each annular lens include: deforming the antenna parameters of the ideal Luneburg lens antenna by using transformation optics theory to obtain the initial radius and initial thickness. By deforming the antenna parameters of the spherical ideal Luneburg lens antenna through transformation optics theory, the initial radius and initial thickness of each layer of lens of the cylindrical Luneburg lens can be obtained.

[0037] After obtaining the respective initial radii and initial thicknesses, for each layer of annular lens, the target radius and target thickness of this layer of annular lens can be determined according to the initial radius and initial thickness corresponding to this layer of annular lens. In one embodiment, as Figure 2 shown, for each layer of annular lens, the steps of determining the target radius and target thickness of this layer of annular lens include:

[0038] Step S210, determining the radius value range of this layer of annular lens according to the initial radius corresponding to this layer of annular lens, and determining the thickness value range of this layer of annular lens according to the initial thickness corresponding to this layer of annular lens;

[0039] Step S220, using the Green's function and the principle of electromagnetic field superposition algorithm to process the radius value range and thickness value range to obtain the normalized outer radius of this layer of annular lens;

[0040] Step S230, respectively determining the target radius and target thickness of this layer of annular lens according to the normalized outer radius.

[0041] Among them, the radius value range is the value range of the target radius, that is, the value range of the target radius; the thickness value range is the value range of the target thickness, that is, the value range of the target thickness. For example, if the initial radius of this layer of annular lens is 5, the radius value range can be determined to be from 3 to 6 accordingly, and the target radius can be determined to be 4.8 after calculation. The normalized outer radius is the value obtained after normalizing the distance between the outer side of the annular lens (i.e., the side away from the center of the circle) and the center of the circle.

[0042] Specifically, determine the radius value range of this layer of annular lens according to the corresponding initial radius of this layer of annular lens, and determine the thickness value range of this layer of annular lens according to the corresponding initial thickness of this layer of annular lens. Use the Green's function and the electromagnetic field superposition algorithm to process the radius value range and the thickness value range to calculate the aperture integral corresponding to this layer of annular lens, so as to obtain the normalized radius of the outer side of this layer of annular lens (i.e., the normalized outer radius). Since the annular lens generally has a certain thickness, the thickness has a certain influence on its radius, and there is a certain gap between the radius of the inner side of the annular lens (i.e., the side close to the center of the circle) and the radius of the outer side (i.e., the side away from the center of the circle). Therefore, to improve the accuracy of the data, this application determines the target radius of this layer of annular lens according to the normalized outer radius of this layer of annular lens, and the difference between the target radius of this layer of annular lens and the target radius of the previous layer of annular lens is the target thickness of this layer of annular lens.

[0043] For each layer of annular lens, steps S210 to S230 can be repeatedly executed to obtain the target radius and target thickness of each annular lens. Further, for the innermost layer of annular lens, that is, the annular lens closest to the center of the circle, it can be a solid structure or have a cavity, and its specific structure can be determined according to factors such as antenna parameters and design requirements. This application does not make specific restrictions on this.

[0044] Step S120, based on the respective initial radii and respective initial thicknesses, determine the dielectric constant values of the respective annular lenses.

[0045] Specifically, according to the respective initial radii and respective initial thicknesses, the dielectric constant values of each layer of annular lens can be obtained. Each layer of annular lens can approximate the continuous node line number distribution of the ideal Luneburg lens through stepwise dielectric constant values, so as to conform to the layering principle of the Luneburg lens antenna. In one embodiment, as Figure 3 shown, the steps of determining the dielectric constant values of the respective annular lenses based on the respective initial radii and respective initial thicknesses include:

[0046] Step S310, use the quasi-conformal transformation theory and Maxwell's equations to process the respective initial radii and respective initial thicknesses to obtain the relative dielectric constant distribution function of the cylindrical Luneburg lens;

[0047] Step S320: Determine the dielectric constant values of each annular lens according to the relative dielectric constant distribution function; wherein, the ratio of the dielectric constant values of two adjacent layers of annular lenses is a fixed value.

[0048] Specifically, the relative dielectric constant distribution function of the cylindrical Luneburg lens can be obtained from the quasi-conformal transformation theory and Maxwell's equations. Taking the Luneburg lens with 5 layers of annular lenses as an example, according to the relative dielectric constant distribution function, 5 step dielectric constant values can be determined, and the continuous dielectric constant distribution of the ideal Luneburg lens can be approximated by the aforementioned 5 step dielectric constant values. At this time, the dielectric constant value of the annular lens at the center is the highest, and the dielectric constant value of the outermost annular lens is the lowest. Moreover, the ratio of the relative dielectric constants of each layer of annular lenses after optimization is a fixed value, that is, the ratio of the dielectric constants of each layer of annular lenses is a fixed value, which conforms to the layering principle of the Luneburg lens antenna. In this way, the spherical wave or cylindrical wave can be converted into a plane wave through the 5-layer cylindrical structure of annular lenses, thereby improving the directional gain of the Luneburg lens antenna.

[0049] Step S130: Transmit a printing instruction to the 3D printer according to each dielectric constant value, each target radius, and each target thickness; the printing instruction is used to instruct the 3D printer to print a cylindrical Luneburg lens.

[0050] Specifically, the cylindrical Luneburg lens can be prepared by 3D printing technology. Based on the dielectric constant values and geometric parameters corresponding to each layer of annular lenses, a printing instruction is generated. Under the control of the printing instruction, the 3D printer can prepare each layer of annular lenses that meet the aforementioned dielectric constant values and geometric parameters through 3D printing, thereby realizing the preparation of the cylindrical Luneburg lens. Among them, the geometric parameters include but are not limited to the target radius, target thickness, and lens curvature, etc.

[0051] In one embodiment, the printing instruction is used to instruct the 3D printer to manufacture the cylindrical Luneburg lens by multiple single-layer prints. Taking the cylindrical Luneburg lens with 5 layers of annular lenses as an example, under the control of the printing instruction, the 3D printer realizes different dielectric constant values and geometric parameters through 5 prints of single-layer cylindrical shells (one layer of cylindrical shell is one layer of annular lens), which can reduce the preparation difficulty and improve the stability of the antenna structure at the same time. Further, each single-layer printing instruction can be transmitted in sequence. The single-layer printing instruction is used to instruct the 3D printer to print according to the dielectric constant value and geometric parameters of one layer of annular lens. Under the instruction of multiple single-layer printing instructions, the 3D printer prints each layer of annular lenses in sequence.

[0052] In the manufacturing method of the above cylindrical Luneburg lens, the cylindrical Luneburg lens includes several layers of annular lenses arranged in sequence from the inside to the outside in the radial direction. By obtaining the initial radius and initial thickness of each annular lens, and respectively determining the target radius and target thickness of each annular lens, where the target radius and the target thickness are obtained by normalizing the initial radius and the initial thickness; and based on each of the initial radii and each of the initial thicknesses, determining the dielectric constant value of each annular lens; according to each of the dielectric constant values, each of the target radii and each of the target thicknesses, transmitting a printing instruction to a 3D printer; the printing instruction is used to instruct the 3D printer to print the cylindrical Luneburg lens, so that a low-profile cylindrical Luneburg lens can be manufactured by a 3D printing method, providing a simple and feasible manufacturing method for a deformed Luneburg lens, and further reducing the manufacturing difficulty of the Luneburg lens.

[0053] It should be understood that although Figures 1-3 the steps in the flowchart are shown in sequence according to the indication of the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless there is a clear indication in this article, the execution of these steps has no strict order limit, and these steps can be executed in other orders. Moreover, Figures 1-3 at least a part of the steps in

[0054] In one embodiment, a Luneburg lens antenna is provided. The Luneburg lens antenna includes a cylindrical Luneburg lens. Among them, the cylindrical Luneburg lens is a Luneburg lens with a cylindrical structure, and the lens parameters of the Luneburg lens can be determined according to actual situations, such as the working frequency band, etc., and the present application does not make specific limitations on this. The cylindrical Luneburg lens includes several layers of annular lenses arranged in sequence from the inside to the outside in the radial direction, and can be manufactured by the above manufacturing method.

[0055] Specifically, the cylindrical Luneburg lens includes several layers of annular lenses arranged in sequence from the inside to the outside in the radial direction. Each layer of annular lens is a cylindrical structure, and the innermost annular lens can be a solid structure or have a cavity, and its specific structure can be determined according to actual situations and design requirements, and the present application does not make specific limitations on this. The multi-layer annular lenses are nested in sequence to obtain the above cylindrical Luneburg lens. Taking the cylindrical Luneburg lens including 5 layers of annular lenses as an example, the 5 layers of annular lenses are the first annular lens 410, the second annular lens 412, the third annular lens 414, the fourth annular lens 416, and the fifth annular lens 418, as Figure 4As shown, the first annular lens 410 is arranged in the innermost layer and nested within the second annular lens 412, that is, the second annular lens 412 is arranged to surround the first annular lens 410. The second annular lens 412, the third annular lens 414, the fourth annular lens 416, and the fifth annular lens 418 are nested in sequence. In the radial direction of the cylindrical Luneburg lens, the first annular lens 410, the second annular lens 412, the third annular lens 414, the fourth annular lens 416, and the fifth annular lens 418 are arranged in sequence. Further, adjacent two layers of annular lenses can be arranged in a fitting manner.

[0056] It should be noted that, in addition to the cylindrical Luneburg lens with the above 5-layer structure, the number of annular lenses can also be determined according to actual situations (such as design parameters of the antenna, etc.). For example, the number of annular lenses can also be 3 layers, 4 layers, 7 layers, etc. The present application does not make specific limitations on this, as long as the Luneburg lens antenna can achieve its above functions.

[0057] It can be understood that the Luneburg lens antenna of the present application can be used to realize the transceiver of signals in any frequency band according to different application scenarios, design positions, etc. In one embodiment, the Luneburg lens antenna of the present application can be a millimeter-wave antenna, that is, the operating frequency band of this antenna is the millimeter-wave band. Thus, the excellent broadband characteristics, fast beam switching ability, wide-angle scanning ability, beam focusing ability, and high-speed data transmission ability of the Luneburg lens antenna can be utilized to realize multi-scenario applications, broaden the application range of the Luneburg lens antenna in the millimeter-wave band, and facilitate large-scale popularization and promotion.

[0058] The Luneburg lens antenna in this embodiment is realized by adopting a cylindrical Luneburg lens, and can achieve the low profile and easy conformal of the Luneburg lens antenna.

[0059] In one embodiment, the dielectric constant values of each annular lens are different from each other, and the dielectric constant values of each annular lens decrease in sequence from the inside to the outside, that is, the dielectric constant value of the innermost annular lens is the highest, and the dielectric constant value of the outermost annular lens is the lowest. The ratio of the dielectric constant values of adjacent two layers of annular lenses is a fixed value.

[0060] Specifically, according to the arrangement order of each annular lens from the inside to the outside in the radial direction, the dielectric constant values of each annular lens decrease in sequence. The dielectric constant value of the innermost annular lens is the highest, and the dielectric constant value of the outermost annular lens is the lowest. At the same time, the ratio of the dielectric constant values of adjacent two layers of annular lenses is a fixed value, that is, for each layer of annular lens, the ratio of its dielectric constant value to the dielectric constant value of the inner (or outer) layer of annular lens is a fixed value, and this ratio is fixed and unchanged.

[0061] Taking the above-mentioned five-layer annular lens as an example, the dielectric constant values of each layer of annular lens from large to small are: the dielectric constant value of the first annular lens 410, the dielectric constant value of the second annular lens 412, the dielectric constant value of the third annular lens 414, the dielectric constant value of the fourth annular lens 416, and the dielectric constant value of the fifth annular lens 418. At the same time, the ratio of the dielectric constant value of the first annular lens 410 to the dielectric constant value of the second annular lens 412, the ratio of the dielectric constant value of the second annular lens 412 to the dielectric constant value of the third annular lens 414, the ratio of the dielectric constant value of the third annular lens 414 to the dielectric constant value of the fourth annular lens 416, and the ratio of the dielectric constant value of the fourth annular lens 416 to the dielectric constant value of the fifth annular lens 418 are all the same.

[0062] In this way, the continuous dielectric constant distribution of the ideal Luneburg lens can be approximated by multiple step dielectric constant values, so that the cylindrical Luneburg lens conforms to the layering principle of the Luneburg lens antenna, and communication can be achieved by using this cylindrical Luneburg lens. At the same time, through the annular lens with a multi-layer cylindrical structure, the low profile and easy conformal of the Luneburg lens antenna can be realized. The annular lens with this multi-layer structure can convert spherical waves or cylindrical waves into plane waves, thereby improving the gain of the Luneburg lens antenna.

[0063] In one embodiment, the thicknesses of each layer of annular lens are different from each other, that is, the thicknesses of any two layers of annular lens are different from each other to realize the characteristics of the Luneburg lens antenna.

[0064] In one embodiment, the Luneburg lens antenna further includes a feed source 420, and the feed source 420 is arranged on the outermost layer of the annular lens. Among them, the outermost layer of the annular lens is the annular lens with the farthest distance from the center of the circle, for example Figure 5 the fifth annular lens 418 in

[0065] Specifically, the specific setting position and specific setting method of the feed source 420 on the outermost layer of the annular lens can be determined according to factors such as the implementation method, quantity, and antenna design parameters of the feed source 420. This application does not make specific restrictions on this. It can be understood that this application can be implemented by using any material, any quantity, and any shape of the feed source 420 in the prior art. When the feed source 420 includes multiple sub-components, the arrangement method between the sub-components can be determined according to factors such as the material, quantity, shape, antenna design parameters, application scenario, and working frequency band of the sub-components. This application does not make specific restrictions on this.

[0066] In one embodiment, such as Figure 5As shown, the feed source 420 may include a plurality of metal sheets 422, each of which is disposed on the outermost annular lens and arranged in sequence along the circumferential direction of the cylindrical Luneburg lens. A certain interval distance may be maintained between the metal sheets 422, and the specific value of the interval distance may be determined according to the actual situation and design requirements, and the present application does not make specific restrictions thereon.

[0067] In this embodiment, by disposing the feed source 420 on the side surface of the cylindrical Luneburg lens, the overall profile height of the Luneburg lens antenna can be reduced, which is beneficial to realizing integration.

[0068] The technical features of the above-described embodiments may be combined arbitrarily. For the sake of brevity of description, not all possible combinations of the technical features in the above-described embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0069] The above-described embodiments merely represent several implementation manners of the present invention, and the description thereof is relatively specific and detailed, but it should not be construed as a limitation on the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the present invention patent shall be subject to the appended claims.

Claims

1. A manufacturing method of a cylindrical Luneburg lens, characterized in that The cylindrical Luneburg lens includes several layers of annular lenses arranged in sequence from the inside to the outside along the radial direction; The method includes: Obtain the initial radius and initial thickness of each of the annular lenses, and respectively determine the target radius and target thickness of each of the annular lenses; The target radius and the target thickness are obtained by normalizing the initial radius and the initial thickness; Among them, the step of obtaining the initial radius and initial thickness of each of the annular lenses includes: Deforming the antenna parameters of an ideal Luneburg lens antenna by using transformation optics theory to obtain the initial radius and the initial thickness; Based on the initial radii and the initial thicknesses of each, determine the dielectric constant values of each of the annular lenses; According to the dielectric constant values of each, the target radii and the target thicknesses of each, transmit a printing instruction to a 3D printer; The printing instruction is used to instruct the 3D printer to print the cylindrical Luneburg lens; Among them, the step of determining the dielectric constant values of each of the annular lenses based on the initial radii and the initial thicknesses of each includes: Processing the initial radii and the initial thicknesses of each by using the quasi-conformal transformation theory and Maxwell's equations to obtain the relative dielectric constant distribution function of the cylindrical Luneburg lens; According to the relative dielectric constant distribution function, determine the dielectric constant values of each of the annular lenses; Among them, the ratio of the dielectric constant values of two adjacent layers of the annular lenses is a fixed value; Among them, the step of respectively determining the target radius and target thickness of each of the annular lenses includes: Determine the radius value range of the current layer of annular lens according to the initial radius corresponding to the current layer of annular lens, and determine the thickness value range of the current layer of annular lens according to the initial thickness corresponding to the current layer of annular lens; Process the radius value range and the thickness value range by using the Green's function and the electromagnetic field superposition algorithm principle to obtain the normalized outer radius of the current layer of annular lens; Determine the target radius and target thickness of the current layer of annular lens according to the normalized outer radius respectively.

2. The manufacturing method of the cylindrical Luneburg lens according to claim 1, characterized in that, The printing instruction is used to instruct the 3D printer to manufacture the cylindrical Luneburg lens by multiple single-layer printing.

3. A Luneburg lens antenna, characterized in that, It includes a cylindrical Luneburg lens and a feed source, the cylindrical Luneburg lens includes several layers of annular lenses arranged in sequence from the inside to the outside along the radial direction; The feed source is arranged on the outermost layer of annular lens, the feed source includes several metal sheets, and a certain interval distance is maintained between each of the metal sheets; The cylindrical Luneburg lens is prepared by using the manufacturing method described in claim 1 or 2.

4. The Luneburg lens antenna according to claim 3, characterized in that, The dielectric constant values of each of the annular lenses are different from each other and decrease in sequence from the inside to the outside, and the ratio of the dielectric constant values of two adjacent layers of the annular lenses is a fixed value.

5. The Luneburg lens antenna according to claim 3 or 4, characterized in that, The number of the annular lenses is 5 layers.

6. The Luneburg lens antenna according to claim 3 or 4, characterized in that, The thicknesses of each of the annular lenses are different from each other.

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