Elliptical cylindrical Luneburg lens antenna and manufacturing method thereof

Abstract

The present invention relates to the field of wireless communication technology, and discloses an elliptical cylindrical Luneburg lens antenna, comprising: a radiation source, and reflective plates and Luneburg lenses respectively arranged on both sides of the radiation source; the Luneburg lens is an elliptical cylinder formed by rolling a dielectric substrate with a plurality of through holes, the long axis of which is perpendicular to the main radiation direction of the radiation source; the elliptical cylinder is provided with n groups of dielectric substrates with decreasing equivalent dielectric constants from the inside to the outside, and each group of dielectric substrates is rolled into m n Layer, m and n are natural numbers greater than zero. When manufacturing this elliptical cylindrical Luneburg lens antenna, holes can be first punched in a dielectric substrate according to a preset pattern. The substrate is then rolled into a cylinder, and then pressed into an elliptical cylinder to form a Luneburg lens. Combined with a radiation source and a reflector, the elliptical cylindrical Luneburg lens antenna is formed. Because the Luneburg lens utilizes a punching and rolling process, it offers low cost, high efficiency, and reduced processing difficulty compared to traditional Luneburg lens manufacturing processes.

Description

Technical Field

[0001] The present invention relates to the field of wireless communication technology, and in particular to an elliptical cylindrical Luneburg lens antenna and a manufacturing method thereof. Background Art

[0002] The Luneburg lens is an important antenna design in the field of electromagnetic antennas. It utilizes a continuous radial dielectric constant distribution to convert spherical waves into plane waves, effectively improving antenna performance. It offers advantages such as a wide operating bandwidth, high gain, a high front-to-back ratio, and good beam consistency. However, the requirement for a continuous radial dielectric constant distribution makes Luneburg lenses difficult to implement and impractical. Existing techniques include directly synthesizing a structure with a continuous dielectric constant distribution from materials to create Luneburg lenses. Others employ 3D printing to create lens dielectric constants in discrete layers. While these methods can produce Luneburg lens prototypes, they generally suffer from difficulties in processing, high cost, and low production efficiency. Therefore, it is imperative to design a low-cost, high-efficiency Luneburg lens that is easy to process. Summary of the Invention

[0003] The present invention is made to solve the above technical problems, and its purpose is to provide an elliptical cylindrical Luneburg lens antenna with low cost, high efficiency and low processing difficulty.

[0004] In order to achieve the above-mentioned object, on the one hand, the present invention provides an elliptical cylindrical Luneburg lens antenna, comprising: a radiation source and a reflector and a Luneburg lens respectively arranged on both sides thereof; the Luneburg lens is an elliptical cylinder formed by rolling a dielectric substrate with a plurality of through holes, the long axis of which is perpendicular to the main radiation direction of the radiation source, and the elliptical cylinder is provided with n groups of dielectric substrates with decreasing equivalent dielectric constants from the inside to the outside, and each group of dielectric substrates is rolled into m n Layer, m and n are natural numbers greater than zero.

[0005] Preferably, the n groups of dielectric substrates are an integrated structure.

[0006] Preferably, when manufacturing the Luneburg lens, the dielectric substrate is first rolled into a cylinder with a radius of R, and then pressed into an elliptical cylinder with a major-minor axis ratio of 1.25-2.

[0007] Preferably, the number of layers m of each set of dielectric substrates is rolled n The calculation formula is:

[0008]

[0009] Where r n is the maximum radius of the cylinder where the nth set of dielectric substrates are located, r0=0, d is the thickness of the dielectric substrate, ε n is the equivalent dielectric constant of the nth group of dielectric substrates.

[0010] Preferably, the ratio of the sum of the areas of the through holes on each group of dielectric substrates to the plane area of ​​the dielectric substrates of the group is f n , and its calculation formula is:

[0011]

[0012] Wherein, ε is the dielectric constant of the dielectric substrate without through holes, u=1, and a is a correction factor.

[0013] Preferably, the length of each set of dielectric substrates is L n , and its calculation formula is:

[0014]

[0015] Where m i is the number of layers of the i-th group of dielectric substrates.

[0016] Preferably, the dielectric substrate is a non-magnetic material with a dielectric constant of 2-3.

[0017] Preferably, the dielectric substrate has a thickness of 8-20 mm.

[0018] Preferably, the through holes in each group of the dielectric substrates are arranged at equal intervals.

[0019] In order to achieve the above object, on the other hand, the present invention provides a method for manufacturing an elliptical cylindrical Luneburg lens antenna, comprising the following steps:

[0020] S1. Determine the radius R of the Luneburg lens before pressing, the number n and thickness d of the dielectric substrates, and the equivalent dielectric constant ε of each dielectric substrate. n ;

[0021] S2. Calculate the number of layers m of each set of dielectric substrates n , the calculation formula is:

[0022]

[0023] Where r n is the maximum radius of the cylinder where the nth set of dielectric substrates are located, r0=0, and d is the thickness of the dielectric substrate;

[0024] S3. Calculate the length L of each set of dielectric substrates n , the calculation formula is:

[0025]

[0026] Where m i is the number of layers of the i-th group of dielectric substrates;

[0027] S4. Calculate the ratio f of the sum of the areas of the through holes on each set of dielectric substrates to the plane area of ​​the dielectric substrates of the set. n , and its calculation formula is:

[0028]

[0029] Wherein, ε is the dielectric constant of the dielectric substrate without through-holes, u=1, and a is the correction factor;

[0030] S5, according to f n A number of through holes arranged at equal intervals are made on each set of dielectric substrates;

[0031] S6. Rolling each set of dielectric substrates together in sequence from inside to outside to form a cylinder, and then pressing it into an elliptical cylinder;

[0032] S7. Make a radiation source and a reflector, and place the reflector and the Luneburg lens on both sides of the radiation source, wherein the long axis of the Luneburg lens is perpendicular to the main radiation direction of the radiation source.

[0033] According to the above description and practice, the elliptical cylindrical Luneburg lens antenna described in the present invention can be manufactured by first punching holes in the dielectric substrate according to a preset rule, then rolling it into a cylinder, and then pressing it into an elliptical cylinder to form a Luneburg lens. The elliptical cylindrical Luneburg lens antenna can be formed by combining a radiation source and a reflector. This antenna has the advantages of a wide operating frequency band, high gain, a high front-to-back ratio, and good beam consistency. At the same time, because the Luneburg lens adopts a punching and rolling process during its production, it has the characteristics of low cost, high efficiency, and low processing difficulty compared to the traditional Luneburg lens production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 Schematic diagram of the side structure of an elliptical cylindrical Luneburg lens antenna involved in one embodiment of the present invention.

[0035] Figure 2 Schematic diagram of the structure of the Luneburg lens involved in one embodiment of the present invention.

[0036] Figure 3 Schematic diagram of the local structure of the Luneburg lens after unfolding in one embodiment of the present invention.

[0037] Figure 4 This is a comparison diagram of the reflection coefficients of an elliptical cylindrical Luneburg lens antenna involved in one embodiment of the present invention, a common feed antenna, and an ideal Luneburg lens antenna.

[0038] Figure 5This is a gain comparison diagram of an elliptical cylindrical Luneburg lens antenna involved in one embodiment of the present invention, a common feed antenna, and an ideal Luneburg lens antenna.

[0039] Figure 6a 、 6b 6c are radiation patterns of the elliptical cylindrical Luneburg lens antenna involved in one embodiment of the present invention at frequencies of 1.8 GHz, 2 GHz and 2.6 GHz.

[0040] Figure 7a 、 7b 7c are the directional patterns of the elliptical cylindrical Luneburg lens antenna at frequencies of 1.8 GHz, 2 GHz and 2.6 GHz involved in one embodiment of the present invention.

[0041] Figure 8a 、 8b 8c are electric field distribution diagrams of the elliptical cylindrical Luneburg lens antenna, the ordinary feed antenna and the ideal Luneburg lens antenna involved in one embodiment of the present invention.

[0042] The reference numerals in the figures are:

[0043] 1. Radiation source, 2. Reflector, 3. Luneburg lens, 4. Dielectric substrate, 5. Through hole. DETAILED DESCRIPTION

[0044] The exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments can be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete and will fully convey the concepts of the exemplary embodiments to those skilled in the art. The described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments.

[0045] In addition, the accompanying drawings are only schematic illustrations of the present disclosure and are not necessarily drawn to scale. The same reference numerals in the figures represent the same or similar parts, and their repeated description will be omitted. It should be noted that in the present disclosure, the terms "including", "configured with", and "set on" are used to express open-ended inclusion and mean that in addition to the listed elements / components / etc., there may be additional elements / components / etc.; the terms "first", "second", etc. are used only as labels and are not intended to limit the number or order of their objects; the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, and 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 direction, be constructed and operate in a specific direction, and therefore should not be understood as limiting the present invention.

[0046] Unless otherwise specified or limited, the terms "mounted," "connected," and "connected" should be interpreted broadly. For example, they can refer to fixed, removable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediary; and internal communication between two components. Those skilled in the art will understand the specific meanings of these terms in the present invention based on the specific circumstances.

[0047] This embodiment discloses an elliptical cylindrical Luneburg lens antenna. Figure 1 The side structure of the elliptical cylindrical Luneburg lens antenna is shown; Figure 2 The structure of Luneburg lens 3 is shown; Figure 3 The planar structure of the Luneburg lens 3 after unfolding is shown. Since the Luneburg lens 3 is long after unfolding, only a partial planar structure is shown in the figure.

[0048] Please refer to Figures 1 to 3 The elliptical cylindrical Luneburg lens antenna comprises a radiation source 1, a reflector 2, and a Luneburg lens 3. The radiation source 1 is a dual-polarized feed antenna operating in the 1.7-2.7 GHz frequency band. The Luneburg lens 3 is positioned at the top of the radiation source 1, and the reflector 2 and Luneburg lens 3 are positioned in the direction of maximum radiation from the radiation source 1. The reflector 2 reflects electromagnetic waves toward the Luneburg lens 3, which then redirects the electromagnetic waves. This further concentrates the electromagnetic wave beam, improving wireless signal strength in a single direction and forming a high-gain, broadband elliptical cylindrical Luneburg lens antenna.

[0049] The Luneburg lens 3 is an elliptical cylinder formed by rolling a dielectric substrate 4 with a plurality of through holes 5, whose long axis is perpendicular to the main radiation direction of the radiation source 1. The elliptical cylinder is provided with n groups of dielectric substrates 4 with decreasing equivalent dielectric constants from the inside to the outside, and each group of dielectric substrates 4 is rolled into m n Layer, m and n are natural numbers greater than zero. The dielectric constant of the dielectric substrate 4 before the through holes 5 are set is a constant value ε. By setting a number of through holes 5 on its surface, its equivalent dielectric constant ε can be changed. n , ε n The ratio of the size of the through holes 5 on each set of dielectric substrates 4 to the plane area of ​​the dielectric substrate 4 is f n Therefore, by changing the total area of ​​the through holes 5 on each set of dielectric substrates 4, the equivalent dielectric constant ε of each set of dielectric substrates 4 can be changed. n , to form n groups of dielectric substrates 4 with decreasing equivalent dielectric constants from the inside to the outside. More specifically, the equivalent dielectric constant ε of each group of dielectric substrates 4 can be set according to actual needs. n , in order to achieve the preset electromagnetic wave refraction effect.

[0050] When manufacturing the elliptical cylindrical Luneburg lens 3 antenna, holes can be first punched in a predetermined pattern on the dielectric substrate 4, then rolled into a cylinder, and then pressed into an elliptical cylinder to form the Luneburg lens 3. When combined with the radiation source 1 and the reflector 2, the elliptical cylindrical Luneburg lens antenna is formed. This antenna has the advantages of a wide operating band, high gain, a high front-to-back ratio, and good beam consistency. Furthermore, because the Luneburg lens 3 is manufactured using a punching and rolling process, it is low-cost, highly efficient, and has a low processing difficulty compared to traditional Luneburg lens manufacturing processes.

[0051] The dielectric substrate 4 is a non-magnetic material with a dielectric constant of 2-3, such as pearl cotton coil with a dielectric constant of 2.32. This material exhibits a certain degree of flexibility, making it easy to roll. Furthermore, when the dielectric substrate 4 is thinner, the required total length increases. When the dielectric substrate 4 is thicker, the total length decreases, but the rolling becomes more difficult. Therefore, the thickness of the dielectric substrate 4 should be between 8-20 mm, which is both convenient for rolling into a cylindrical shape and does not increase the length, thus facilitating the production of the Luneburg lens 3.

[0052] In addition, in order to make the equivalent dielectric constant of each set of dielectric substrates 4 more uniformly distributed along the radial direction, in this embodiment, the through holes 5 in each set of dielectric substrates 4 are arranged at equal distances. Figure 3 As shown, there are two sets of dielectric substrates 4, each of which has a number of rectangular through holes 5 evenly spaced. The through holes 5 in the right set of dielectric substrates 4 are larger than the through holes 5 in the left set of dielectric substrates 4. Therefore, the ratio of the sum of the areas of the through holes 5 in the right set of dielectric substrates 4 to the plane area of ​​the dielectric substrates 4 is f. n Greater than the f of the dielectric substrate 4 on the left side n .from Figure 3 It can be seen that two adjacent groups of dielectric substrates 4 are of an integrated structure. In this embodiment, n groups of dielectric substrates 4 are all configured as an integrated structure. It is only necessary to provide through holes 5 of different sizes and / or different spacings on each group of dielectric substrates 4 to achieve a different equivalent dielectric constant for each group of dielectric substrates 4. At the same time, this integrated structure also facilitates the formation of the Luneburg lens 3 by a single rolling operation.

[0053] The Luneburg lens 3 is an elliptical cylinder with its minor axis along Figure 1 The vertical direction and the long axis along Figure 1 In the horizontal direction, this design facilitates a narrower beamwidth in the vertical plane, which can better meet the requirements of long-distance transmission and wide coverage. The ratio of the major and minor axes of the elliptical cylinder is 1.25-2, which is conducive to obtaining a good horizontal and vertical beamwidth.

[0054] The elliptical cylinder structure of the Luneburg lens 3 can better narrow the lobe width and reduce the sidelobe level, so that when the electromagnetic wave propagates in two mutually perpendicular directions, the lobe width achieves a narrower angle on the surface where the minor axis is located, thereby achieving the effect of fine-tuning the lobe width. In addition, the preparation of the Luneburg lens 3 through a rolling process can, to a certain extent, avoid the complex process of traditional spherical Luneburg lenses. Traditional spherical Luneburg lenses require a moving feed source to achieve the effect of beam scanning, while the artificial dielectric lens antenna in this embodiment can achieve the effect of beam scanning by cross-stacking the Luneburg lenses 3.

[0055] The following describes the manufacturing process of the elliptical cylindrical Luneburg lens antenna in detail with reference to a specific embodiment, which specifically includes the following steps:

[0056] Step S1: Determine the radius R of the Luneburg lens before pressing, the number n and thickness d of the dielectric substrates, and the equivalent dielectric constant ε of each dielectric substrate. n These parameters are known values ​​and their values ​​need to be set according to actual needs.

[0057] For example, in this embodiment, when the Luneburg lens in the elliptical cylindrical Luneburg lens antenna is rolled into a cylinder, its radius R = 190 mm and its length is 200 mm; there are 5 groups of dielectric substrates with different dielectric constants, that is, n = 5; the thickness of the dielectric substrate is 10 mm, that is, d = 10 mm; the equivalent dielectric constants of each group of dielectric substrates from the inside to the outside are: ε1 = 1.87, ε2 = 1.69, ε3 = 1.51, ε4 = 1.33, ε5 = 1.21.

[0058] Step S2: Calculate the number of layers m of each set of dielectric substrates n .

[0059] When calculating the number of layers m n When rolling the dielectric substrate into a cylindrical shape, the radius of the outermost circle of each layer of dielectric substrate must be calculated first. Then, the number of layers m of each dielectric substrate can be obtained by dividing the difference in radius between adjacent groups by the thickness of the dielectric substrate. n The radius of the outermost circle of each layer of dielectric substrate after being rolled into a cylindrical shape is related to the classic Luneburg lens formula, that is, formula (2). Specifically, the calculation formula is:

[0060]

[0061] It should be noted that for the centermost group of dielectric substrates, r0 will appear during the calculation, and the value of r0 is recorded as 0. After substituting the above parameters into formula (1) and formula (2), it can be obtained that m1=8, m2=4, m3=3, m4=2, and m5=2. That is, from the inside to the outside, the first group of dielectric substrates needs to be rolled into 8 layers, the second group of dielectric substrates needs to be rolled into 4 layers, the third group of dielectric substrates needs to be rolled into 3 layers, the fourth group of dielectric substrates needs to be rolled into 2 layers, and the fifth group of dielectric substrates needs to be rolled into 2 layers. It should be noted that when rolling, part of the dielectric substrate in the center needs to be used as a roll, and this roll is also recorded as a layer, so Figure 1 There are 19 layers from the inside to the outside.

[0062] Step S3: Calculate the length L of each set of dielectric substrates n .

[0063] Since we know the number of layers and thickness of each set of dielectric substrates, we can calculate the length L of each set of dielectric substrates. n Specifically, the calculation formula is:

[0064]

[0065] Where m i is the number of layers of the i-th group of dielectric substrates.

[0066] Substituting the above parameters into formulas (3) and (4), we can obtain L1 = 2200, L2 = 2639, L3 = 3392, L4 = 2073, and L5 = 2325. That is, from the inside to the outside, the length of the first set of dielectric substrates is 2200 mm, the length of the second set of dielectric substrates is 2639 mm, the length of the third set of dielectric substrates is 3392 mm, the length of the fourth set of dielectric substrates is 2073 mm, and the length of the fifth set of dielectric substrates is 2325 mm.

[0067] Step S4: Calculate the ratio f of the sum of the areas of the through holes on each set of dielectric substrates to the plane area of ​​the dielectric substrates of the set n .

[0068] According to the dielectric mixing equivalent theory, the value of the equivalent dielectric constant of the dielectric substrate after punching is related to f n Therefore, under the premise of knowing the equivalent dielectric constant of each set of dielectric substrates, f can be deduced inversely. n Specifically, the calculation formula is:

[0069]

[0070] Wherein, ε is the dielectric constant of the dielectric substrate without through-holes. Once the material of the dielectric substrate is known, its dielectric constant is also a known value. u is the magnetic permeability of the dielectric substrate. Since the dielectric substrate is a non-magnetic material, u = 1. a is a correction factor, the value of which is related to the dielectric constant of the dielectric substrate material and air, as well as the material loss. Since the dielectric constant of air is 1, its value is only related to the material properties. Once the material of the dielectric substrate is determined, the value of a can also be considered a known value.

[0071] Substituting the above known parameters into formula (5), we can calculate: f1 = 0.3, f2 = 0.425, f3 = 0.56, f4 = 0.71, f5 = 0.86. That is, from the inside to the outside, the ratio of the sum of the areas of the through holes on the first group of dielectric substrates to the plane area of ​​the dielectric substrates is 0.3; the ratio of the sum of the areas of the through holes on the second group of dielectric substrates to the plane area of ​​the dielectric substrates is 0.425; the ratio of the sum of the areas of the through holes on the third group of dielectric substrates to the plane area of ​​the dielectric substrates is 0.56; the ratio of the sum of the areas of the through holes on the fourth group of dielectric substrates to the plane area of ​​the dielectric substrates is 0.71; and the ratio of the sum of the areas of the through holes on the fifth group of dielectric substrates to the plane area of ​​the dielectric substrates is 0.86.

[0072] Step S5: According to f n A number of through holes arranged at equal intervals are made on each set of dielectric substrates.

[0073] Specifically, in this embodiment, the length of the Luneburg lens is 200 mm, that is, the width of the dielectric substrate is 200 mm, and the length L of each set of dielectric substrates is n It has been calculated that the corresponding plane area S of each set of dielectric substrates is n =200L n , the sum of the areas of the through holes on each set of dielectric substrates s n =S n f n In this embodiment, rectangular through-holes are used. Given the total area of ​​the through-holes, the size and number of the through-holes can be determined based on actual needs, and these through-holes can be evenly spaced on each set of dielectric substrates. To achieve a more even distribution of the through-holes, they can be square or circular, with a side length or diameter between 3 and 10 mm.

[0074] Since each set of dielectric substrates adopts an integrated structure in this embodiment, when punching holes, it is only necessary to mark the boundary lines between two adjacent sets of dielectric substrates on the entire dielectric substrate according to the length of each set of dielectric substrates, and then make through holes between each boundary line according to the arrangement rules of the respective through holes.

[0075] Step S6: Roll each set of dielectric substrates together in sequence from the inside out to form a cylinder, and then press it into an elliptical cylinder.

[0076] Since each set of dielectric substrates in this embodiment utilizes a unibody structure, it is sufficient to simply roll the entire dielectric substrate into a cylinder, starting with one end of the first set as the reel. Pressure is then applied to the sides of the cylinder, pressing it into the desired elliptical cylindrical shape based on the desired ratio of the major axis to the minor axis. Furthermore, to stabilize the shape of the pressed Luneburg lens, glue can be applied to the sides of the dielectric substrate before rolling, or a restraining structure, such as a restraining band, can be placed around the periphery after pressing and shaping.

[0077] Step S7: fabricate a radiation source and a reflector plate, and arrange the reflector plate and the Luneburg lens on both sides of the radiation source, wherein the long axis of the Luneburg lens is perpendicular to the main radiation direction of the radiation source.

[0078] The above takes a dual-polarized feed antenna with an operating frequency band of 1.7-2.7 GHz as an example to describe the structure of the elliptical cylindrical Luneburg lens antenna and test its performance. It should be noted that the present invention aims to disclose an elliptical cylindrical Luneburg lens antenna with the above-mentioned structural form, and does not limit the structure of the radiation source and the operating frequency band. In other words, those skilled in the art can realize antennas applied to other frequency bands based on this structural form, which should also be included in the scope of protection of the present invention.

[0079] Figure 4 The following is a comparison of the reflection coefficients of the elliptical cylindrical Luneburg lens antenna in this embodiment, a common feed antenna, and an ideal Luneburg lens antenna. All three use the same feed. Since the dual-polarized feed antenna has port symmetry, only one of the ports is checked, and the results of the other port are similar. Figure 4 It can be seen that within the 1.7GHz-2.7GHz range, the reflection coefficients of the feed antenna, the ideal Luneburg lens antenna, and the elliptical Luneburg lens antenna in this embodiment are all below -14dB. In fact, the elliptical Luneburg lens antenna in this embodiment has a better reflection coefficient at some frequencies, which is more conducive to the transmission of electromagnetic waves.

[0080] Figure 5The following is a gain comparison chart of the elliptical cylindrical Luneburg lens antenna in this embodiment, a common feed antenna, and an ideal Luneburg lens antenna, all of which use the same feed. As can be seen from the figure, the gain of the feed antenna is 7.5dBi-8.5dBi in the 1.7GHz-2.7GHz range, while the gain of the ideal Luneburg lens antenna is 15.5dBi-18dBi, which is an increase of at least 8dBi over the common feed antenna. The gain of the elliptical cylindrical Luneburg lens antenna in this embodiment is 15dBi-17.7dBi, which is an increase of at least 7.5dBi over the common feed antenna. This difference is only 0.5dBi compared to the ideal Luneburg lens antenna, demonstrating the effectiveness of this process.

[0081] Figure 6a 、 6b 6c and 6d show the radiation patterns of the elliptical cylindrical Luneburg lens antenna in this embodiment at frequencies of 1.8 GHz, 2 GHz, and 2.6 GHz, respectively. Each figure shows the radiation lobe pattern in the vertical and horizontal planes. As can be seen from the figures, the vertical and horizontal beamwidths at these three frequencies are essentially the same, demonstrating that this wound Luneburg lens exhibits excellent radiation uniformity, i.e., excellent beam consistency.

[0082] Figure 7a 、 7b 7c and 7d show the radiation patterns of the elliptical cylindrical Luneburg lens antenna in this embodiment at frequencies of 1.8 GHz, 2 GHz, and 2.6 GHz, respectively. Each figure shows the radiation patterns in the vertical and horizontal planes. As can be seen from the figures, the antenna exhibits excellent directivity in both the horizontal and vertical planes at all three frequencies, with front-to-back ratios exceeding 23 dB, demonstrating high front-to-back ratios and good radiation efficiency.

[0083] Figure 8a 、 8b Figures 8c and 8d show the electric field distribution of the elliptical cylindrical Luneburg lens antenna in this embodiment, a conventional feed antenna, and an ideal Luneburg lens antenna, all of which use the same feed. As can be seen from the figure, the elliptical cylindrical Luneburg lens antenna in this embodiment, implemented by perforating and winding a dielectric substrate, and the ideal Luneburg lens antenna achieve the same effect, both converting spherical waves emitted by the feed source into plane waves. This also demonstrates the effectiveness and scientific nature of the process used to develop the elliptical cylindrical Luneburg lens antenna.

[0084] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the invention can be embodied in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as illustrative and non-restrictive, and the scope of the invention is defined by the appended claims, not the foregoing description, and all variations within the meaning and range of equivalents of the claims are intended to be included therein. Any reference sign in a claim should not be construed as limiting the claim to which it relates.

Claims

1. An elliptical cylindrical Luneburg lens antenna, characterized in that: include: A radiation source and a reflector and a Luneburg lens respectively arranged on both sides of the radiation source; The Luneburg lens is an elliptical cylinder formed by rolling a dielectric substrate with several through holes, whose long axis is perpendicular to the main radiation direction of the radiation source. The elliptical cylinder is provided with n groups of dielectric substrates with decreasing equivalent dielectric constants from the inside to the outside, and each group of dielectric substrates is rolled into m n layer, m and n are natural numbers greater than zero; when manufacturing the Luneburg lens, the dielectric substrate is first rolled into a cylinder with a radius of R, and then pressed into an elliptical cylinder; The number of layers of each set of dielectric substrates is m n The calculation formula is: Where r n is the maximum radius of the cylinder where the nth set of dielectric substrates are located, r0=0, d is the thickness of the dielectric substrate, ε n is the equivalent dielectric constant of the nth group of dielectric substrates; The ratio of the sum of the areas of the through holes on each group of dielectric substrates to the plane area of ​​the dielectric substrates is f n , and its calculation formula is: Wherein, ε is the dielectric constant of the dielectric substrate without through holes, u=1, and a is a correction factor.

2. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The n groups of dielectric substrates are of an integrated structure.

3. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The ratio of the major axis to the minor axis of the elliptical cylinder is 1.25-2.

4. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The length of each set of dielectric substrates is L n , and its calculation formula is: Where m i is the number of layers of the i-th group of dielectric substrates.

5. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The dielectric substrate is a non-magnetic material with a dielectric constant of 2-3.

6. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The thickness of the dielectric substrate is 8-20 mm.

7. The elliptical cylindrical Luneburg lens antenna according to claim 1, wherein: The through holes in each group of the dielectric substrates are arranged at equal intervals.

8. A method for manufacturing an elliptical cylindrical Luneburg lens antenna, for manufacturing the elliptical cylindrical Luneburg lens antenna according to any one of claims 1 to 7, characterized in that: include: S1. Determine the radius R of the Luneburg lens before pressing, the number n and thickness d of the dielectric substrates, and the equivalent dielectric constant ε of each dielectric substrate. n ; S2. Calculate the number of layers m of each set of dielectric substrates n , the calculation formula is: Where r n is the maximum radius of the cylinder where the nth set of dielectric substrates are located, r0=0, and d is the thickness of the dielectric substrate; S3. Calculate the length L of each set of dielectric substrates n , the calculation formula is: Where m i is the number of layers of the i-th group of dielectric substrates; S4. Calculate the ratio f of the sum of the areas of the through holes on each set of dielectric substrates to the plane area of ​​the dielectric substrates of the set. n , and its calculation formula is: Wherein, ε is the dielectric constant of the dielectric substrate without through-holes, u=1, and a is the correction factor; S5, according to f n A number of through holes arranged at equal intervals are made on each set of dielectric substrates; S6. Rolling each set of dielectric substrates together in sequence from inside to outside to form a cylinder, and then pressing it into an elliptical cylinder; S7. Make a radiation source and a reflector, and place the reflector and the Luneburg lens on both sides of the radiation source, wherein the long axis of the Luneburg lens is perpendicular to the main radiation direction of the radiation source.

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