Radome and producing method of radome

Abstract

To provide a radome which makes it easy to widen a range through which radio waves pass, and a producing method of the radome.SOLUTION: A radome includes: a first dielectric part located at a reference position at which an incident angle of a radio wave transmitted and received from a communication device is 0 degrees and having a reference relative dielectric constant at the reference position; and a second dielectric part located around the reference position and having a relative dielectric constant smaller than the reference relative dielectric constant and smaller as the distance from the reference position increases.SELECTED DRAWING: Figure 17

Description

[Technical Field]

[0001] The present disclosure relates to a radome and a method for manufacturing a radome. [Background technology]

[0002] There is a demand for more efficient radio wave transmission in communication devices such as antennas. In particular, radomes, which serve as the housings for these devices, are required to have lower dielectric constant and better radio wave permeability. In such a radome, the thickness of the plate is set to an integral multiple of half the wavelength of the radio waves, thereby reducing attenuation of the radio waves as they pass through the radome and increasing radio wave transparency.

[0003] As a technique for increasing radio wave transparency, the radome disclosed in Patent Document 1 is known. This radome is formed on a curved surface, and in order to make the transmitted phase amount uniform, the dielectric constant of the radome wall near the central axis of the antenna is configured to be higher than that of other parts of the radome. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Utility Model Application Publication No. 59-6312 Summary of the Invention [Problem to be solved by the invention]

[0005] However, with the radome described in Patent Document 1, it is sometimes difficult to widen the transmission range.

[0006] An object of the present disclosure is to provide a radome and a method for manufacturing a radome that solves the above-mentioned problems. [Means for solving the problem]

[0007] A radome according to one embodiment of the present disclosure comprises a first dielectric portion located at a reference position where the incident angle of radio waves transmitted or received from an electronic device is 0 degrees and having a reference dielectric constant at the reference position, and a second dielectric portion located in the vicinity of the reference position and having a dielectric constant that is smaller than the reference dielectric constant and that decreases with increasing distance from the reference position.

[0008] A method for manufacturing a radome according to one embodiment of the present disclosure includes placing a first dielectric part having a reference relative dielectric constant at a reference position where the incident angle of radio waves transmitted or received from a communication device is 0 degrees, and placing a second dielectric part around the reference position, the second dielectric part having a relative dielectric constant that is smaller than the reference relative dielectric constant and that decreases with increasing distance from the reference position. [Effects of the Invention]

[0009] According to the above aspect, it is easy to widen the angle of the radio wave transmission range. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a front view of a cover equipped with a radome according to the present disclosure. [Figure 2] FIG. 2 is a plan view of FIG. [Figure 3] FIG. 1 is an image diagram of a radome according to the present disclosure. [Figure 4] FIG. 2 is a configuration diagram showing a portion of a radome according to the present disclosure. [Figure 5] FIG. 2 is a front view for explaining the angle of incidence of radio waves on a radome according to the present disclosure. [Figure 6] 1 is a table showing the relationship between the angle of incidence and the porosity. [Figure 7] FIG. 2 is an explanatory diagram for explaining the refraction angle of a radio wave to a radome according to the present disclosure. [Figure 8] 10A and 10B are diagrams showing how a radome material is extruded from a nozzle in the manufacturing process of the radome according to the present disclosure. [Figure 9] FIG. 10 is a diagram showing a filler for forming a gap in the radome. [Figure 10]This is another form of the filler shown in FIG. [Figure 11] FIG. 1 is a diagram showing a solid to be measured. [Figure 12] FIG. 1 is a diagram showing a foam to be measured. [Figure 13] 10 is a graph showing the relationship between frequency and relative dielectric constant, which is a measurement result. [Figure 14] FIG. 1 is a diagram showing a solid to be measured. [Figure 15] FIG. 1 is a diagram showing a foam to be measured. [Figure 16] 10 is a graph showing the relationship between frequency and dielectric constant, which is a measurement result. [Figure 17] FIG. 1 is a diagram illustrating the configuration of a radome according to the present disclosure. [Figure 18] FIG. 1 is a block diagram illustrating a radome manufacturing system according to the present disclosure. [Figure 19] 1 is a flowchart illustrating a method for manufacturing a radome according to the present disclosure. [Figure 20] 1 is a flowchart illustrating a method for manufacturing a radome according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0011] Each embodiment will be described below with reference to the drawings. In all drawings, the same or corresponding components are designated by the same reference numerals, and common descriptions will be omitted.

[0012] First Embodiment Hereinafter, an embodiment according to the present disclosure will be described with reference to FIGS. 1 and 2 show a radome 1, which is installed in a mounting hole 3 of a housing 2 to form a part of a cover C of a communication device A such as an antenna. As shown in Figures 3 and 4, this radome 1 is composed of a first dielectric part 10 located at a reference position T0 where the incident angle of the radio wave W0 (wavelength λ) transmitted or received from communication device A is 0 degrees, and a second dielectric part 11 located around the reference position T0, and is formed in a plate shape and with a uniform thickness as a whole.

[0013] As shown in FIG. 4, the first dielectric portion 10 has a reference relative dielectric constant ε at a reference position T0 where the incident angle of the radio wave W is 0 degrees. The second dielectric portion 11 has a dielectric constant ε that is smaller than the reference dielectric constant ε and that decreases as it moves away from the reference position T0. θ It has. As shown in FIG. 4, the second dielectric portion 11 has a plurality of dielectric portions 11A, 11B (two portions in this example of the present embodiment). These dielectric portions 11A and 11B have a relative dielectric constant ε different from that of the first dielectric portion 10. θ (described later), and for example, the relative dielectric constant ε decreases as the distance from the reference position T0 increases. θ It has the following characteristics. The first dielectric portion 10 and the second dielectric portion 11 are formed as a whole from a single member, and the relative dielectric constant of the second dielectric portion 11 is adjusted in stages by adjusting the placement ratio of the gaps 12 according to the incident angle θ of the radio wave Wθ (i.e., for each dielectric portion 11A, 11B).

[0014] And the relative dielectric constant ε θ is set to a value at which the amount of attenuation of the radio wave Wθ is minimized by adjusting the porosity of the voids 12 in the second dielectric portion 11. These voids 12 are formed by mixing hollow filler into the second dielectric portion 11. In the second dielectric portion 11, a porous body 13 having a large number of voids 12 is formed by blending hollow filler into the radome material.

[0015] Next, with reference to FIGS. 5 to 10, methods for setting the relative dielectric constant of the second dielectric portion 11 disposed in the path of the radio wave Wθ from the communication device A will be described in order. In this method of setting the relative dielectric constant, the worker adjusts the void ratio by mixing hollow filler into the second dielectric portion 11 as described above. Specifically, in this method of setting the relative dielectric constant, the worker adjusts the relative dielectric constant of each dielectric portion 11A, 11B of the second dielectric portion 11 so that the attenuation of the radio waves Wθ becomes a minimum value based on the following (Equation 1) to (Equation 7) which hold between the incident angle of the radio waves Wθ from the communication device A at that position, the relative dielectric constant at that position, and the attenuation of the radio waves Wθ.

[0016] Furthermore, the radome 1 is created using a 3D (dimensional) printer that uses fused deposition modeling (FDM), which does not require consideration of material removal, since it has an internal void structure.

[0017] In the following description, the radio wave incident on the radome 1 at the reference position T0 where the incident angle is 0 degrees is referred to as radio wave WO, and the radio wave incident on the radome 1 at an incident angle of θ degrees is referred to as radio wave Wθ (see Figure 5). In the following description, the incident angle of the radio wave Wθ incident on the radome 1 is referred to as the incident angle θ, the refraction angle when the incident angle of the radio wave Wθ is θ is referred to as the refraction angle θ', the thickness of the radome 1 (see Figure 7) is referred to as the thickness t, and the wavelengths of the radio wave W0 and the radio wave Wθ are referred to as the wavelength λ.

[0018] In the following description, the relative dielectric constant of the radome material is referred to as the relative dielectric constant ε, the relative dielectric constant of the porous body 13 in the radome 1 is referred to as the relative dielectric constant ε', and the relative dielectric constant of the radome 1 through which the radio wave Wθ passes when the incident angle is θ is referred to as the relative dielectric constant ε θ It shows: In the following description, the porosity of the porous body 13 in the radome 1 is defined as φ, and the porosity of the radome 1 when the radio wave Wθ passes through at an incident angle θ is defined as Φ. θ It shows:

[0019] First, formula (1) shows the relationship between the relative permittivity ε of the radome material, the thickness t of the radome 1, and the wavelength λ of the radio waves Wθ in order to optimally suppress the attenuation of the radio waves Wθ. Note that in formula (1), a smaller integer results in a thinner thickness t of the radome 1, which leads to weight reduction, but it also reduces strength, so it is desirable to use the smallest value that satisfies the usage requirements.

[0020]

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[0021] Equation (2) is an equation for calculating the refraction angle θ′ when the incident angle of the radio wave Wθ is θ on a radome material with a relative dielectric constant ε as shown in FIG. The calculation result of this equation (2) is used in equation (4) described later. Also, Fig. 6 shows the relationship between the relative dielectric constant ε of the radome material, the incident angle θ of the radio wave Wθ, and the porosity Φθ of the radome 1, which will be described later.

[0022]

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[0023] Equation (3) shows the condition for optimally suppressing the amount of attenuation of the radio wave Wθ when the incident angle of the radio wave Wθ is θ. As with equation (1), the smaller the integer value, the thinner the thickness t of the radome 1, which leads to weight reduction, but the strength will decrease, so it is desirable to use the smallest value that satisfies the usage requirements (see Figure 7).

[0024]

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[0025] Equation (4) is calculated from the refraction angle θ' when the incident angle of the radio wave Wθ is θ and the relative dielectric constant ε of the radome material, which are calculated by equation (2), to find the relative dielectric constant ε of the radome 1 through which the radio wave Wθ passes when the incident angle is θ. θ This is the formula to obtain

[0026]

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[0027] Equation (5) shows the relationship between the relative permittivity ε' of the porous body in the radome 1 and the void fraction Φ (100×void volume / conductor volume).

[0028]

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[0029] Here, the relative dielectric constant ε' of the porous body 13 in the radome 1 and the relative dielectric constant ε of the radome 1 through which the radio wave Wθ passes when the incident angle is θ are θ The relationship between θ When the condition ε' is satisfied, the transmission loss due to interference with the radome material is minimized regardless of the incident angle θ of the radio wave Wθ. That is, in the method for setting the relative dielectric constant of the radome 1 in this embodiment, the porosity Φ of the radome 1 along the radio wave path at the incident angle θ is θ However, by designing it to satisfy the following equations (6) and (7), it is possible to minimize the transmission loss due to interference of the radio wave Wθ with the radome material at all angles.

[0030] Based on the above equations (4) and (5), equation (6) is used to determine the porosity Φ of the porous body portion of the radome through which the radio wave Wθ passes, which can optimally suppress the attenuation of the radio wave Wθ when the incident angle of the radio wave Wθ is θ. θ The formula for calculating "ε θ =ε' is derived based on Equation (7) is obtained by substituting equation (2) into equation (6) above, and is the porosity Φ of the porous part of the radome through which the radio wave Wθ passes, which minimizes the attenuation of the radio wave Wθ when the incident angle of the radio wave Wθ is θ. θ is a formula for calculating the dielectric constant ε of the radome material and the incident angle θ of the radio wave Wθ.

[0031]

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[0032]

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[0033] In the method for setting the relative dielectric constant of the radome 1 as described above, the porosity Φ of the porous body portion of the radome at which the attenuation of the radio wave Wθ becomes a minimum value is determined based on the above-mentioned formulas (1) to (7). θ can be calculated. and porosity Φ θ When calculating, the porosity Φ is calculated using a fused deposition model 3D printer. θ By blending a hollow filler to obtain the above, the radome 1 made of the porous body 13 can be produced. FIG. 6 shows an example of the relationship between the incident angle θ of the radio wave Wθ and the void ratio Φθ when the relative dielectric constant ε of the radome material is 3, calculated based on the above-mentioned formulas (1) to (7).

[0034] As shown in Figure 8, an operator forms the porous body 13 of the radome 1 by extruding and layering a resin material 21 (e.g., PPE (Poly Phenylene-Ether) resin, ABS (Acrylonitrile-Ethylene-Styrene) resin) made of a thermoplastic resin melted at high temperature from a nozzle 20 of a 3D printer that uses the fused deposition modeling method. The resin material 21 extruded from the nozzle 20 contains fillers 22 and 23 for forming the gap 12 of the radome 1.

[0035] The filler 22 may be formed in a columnar shape in the center of the void 12 as shown in FIG. 9, and support the resin material 21 at the top and bottom of the void 12 . Furthermore, the filler 23 is not limited to forming the gap 12, but may be of a type that supports the upper branched portion of the resin material 21 formed in a Y shape as shown in FIG.

[0036] In this embodiment, the worker then used a printer manufactured by Japan 3D Printer Co., Ltd. to create a sample of the desired radome. Specifically, the worker uses RP-21-01 (White), an ABS filler compatible with the printer, to create a gap of 0.1 mm x 0.1 mm x 0.1 mm within the resin material 21 according to the incident angle θ of the radio wave Wθ, at the ratio calculated by equation 7, and forms a radome that is 100 mm long x 100 mm wide x 10 mm thick. In this embodiment, the radio wave characteristics were measured using this radome, and as a result, it was found that attenuation of the radio wave Wθ can be suppressed to 1 dB or less at a frequency of 8 GHz over a wide range of incident angles from 15 to 75°.

[0037] Here, the results of an investigation into the relationship between the dielectric constant of a porous body and voids are shown. In one example, an operator prepared a PPE solid S1 with a thickness t of 2 mm and a porous PPE foam S2 with a thickness t of 4 mm, as shown in Figures 11 and 12. Here, PPE foam S2 was formed by foaming PPE solid S1 so that its thickness was doubled. The results of investigating the relationship between frequency and relative permittivity of these are shown in Figure 13. The measurement results in Figure 13 confirm that the 4 mm thick porous foam S2 has a lower relative dielectric constant in all frequency bands compared to the 2 mm thick PPE solid S1. The relative dielectric constant of the foam S2 is indicated by a broken line S2', and the relative dielectric constant of the solid S1 is indicated by a solid line S1'.

[0038] In another example, as shown in Figures 14 and 15, a PPE solid S3 with a thickness t of 2.5 mm and a porous PPE foam S4 with the same thickness t of 2.5 mm were prepared. The results of investigating the relationship between frequency and dielectric constant are shown in Figure 16. The measurement results in FIG. 16 confirm that the porous foam S4 has a lower dielectric constant in all frequency bands compared to the solid S3 of the same thickness. The dielectric constant of the foam S4 is indicated by a dashed line S4', and the dielectric constant of the solid S3 is indicated by a solid line S3'. Generally, if the voids in the foam S4 are sufficiently smaller than the wavelength of the radio waves passing through, the radio waves will not recognize the voids and will behave as if they were a single structure. Therefore, based on the measurement results in Figures 13 and 16, the difference between the PPE solids S1 and S3 and the foams S2 and S4 can be seen in terms of radio waves as a difference in dielectric constant rather than a difference in the thickness of the structures.

[0039] According to the radome 1 according to the present embodiment described above, the dielectric constant ε 1 is located in the vicinity of the reference position T0 of the first dielectric portion 10, and is smaller than the reference relative dielectric constant ε 2 and decreases with increasing distance from the reference position T0. θ By providing the second dielectric portion 11 having the above specific configuration, it is possible to suppress the attenuation of radio waves. Therefore, the radome 1 according to this embodiment makes it easy to widen the range through which radio waves penetrate. Furthermore, by creating the second dielectric portion 11 separately for the dielectric portions (11A, 11B), it is possible to set the relative dielectric constant in stages according to the angle of incidence of the radio wave Wθ.

[0040] Furthermore, in the radome 1 according to this embodiment, the second dielectric portion 11 adjacent to the first dielectric portion 10 is formed of the porous body 13, thereby reducing the overall weight and minimizing the amount of attenuation of the radio waves W0 / Wθ over a wide range of angles while maintaining the degree of freedom in shape. As specific examples, it becomes possible to widen the application range of 5G / 6G terminals, widen the detection range of radio wave radar devices, and improve the degree of freedom in the shape of the wide-angle radome.

[0041] (Variation) In the above embodiment, the radome 1 is formed into a plate-like body with a flat surface, but the present invention is not limited to this, and the outer surface of the radome 1 may be formed into a curved surface. In a structure in which the outer surface of the radome 1 is formed into a curved surface, the calculation of the void ratio becomes slightly complicated, but this has the effect of making the entire structure more robust.

[0042] Second Embodiment An embodiment according to the present disclosure will be described below with reference to FIG. FIG. 17 shows a radome 100 having a first dielectric portion 101 and a second dielectric portion 102.

[0043] The first dielectric portion 101 is located at a reference position T0 where the incident angle of the radio wave transmitted from or received by the communication device is 0 degrees, and has a reference relative dielectric constant at the reference position T0. The second dielectric portion 102 is located in the vicinity of the reference position T0, and has a relative dielectric constant that is smaller than the reference relative dielectric constant and that decreases with increasing distance from the reference position T0.

[0044] According to the radome 100 of this embodiment, the attenuation of radio waves can be suppressed by providing a second dielectric portion 102 that is located around the reference position T0 of the first dielectric portion 101 and has a dielectric constant that is smaller than the reference dielectric constant and that decreases with increasing distance from the reference position. Therefore, the radome 1 according to this embodiment makes it easy to widen the range through which radio waves penetrate.

[0045] Third Embodiment An embodiment according to the present disclosure will be described below with reference to FIGS. FIG. 18 is a block diagram showing a radome manufacturing system 200 according to one embodiment of the present disclosure, which includes an input means 201 for inputting initial data, a calculation means 202 for performing various calculations, and a 3D printer 203 serving as an output means.

[0046] The input means 201 is composed of a keyboard or a device for inputting various data, and inputs initial data such as the relative dielectric constant ε of the radome material, the thickness t of the radome 1, and the wavelength λ of the radio wave Wθ.

[0047] The calculation means 202 calculates the porosity Φ of the porous body portion of the radome at which the attenuation of the radio wave Wθ becomes a minimum value according to the incident angle θ of the radio wave Wθ passing through the radome 1, based on the data taken in by the input means 201 and the above-mentioned equations 1 to 7. θ , and the porosity Φ θ The amount of hollow filler to be blended is calculated to obtain the above.

[0048] Based on the calculation results of the calculation means 202, the 3D printer 203 creates a radome 1 (see Figure 1) consisting of a first dielectric part 10 having a reference relative dielectric constant ε and a second dielectric part 102 located around the reference position T0.

[0049] Next, with reference to FIG. 19, the radome manufacturing method used and executed by the calculation means 202 will be described step by step (ST). [Step ST1] Through the input means 201, the calculation means 202 takes in initial data such as the relative dielectric constant ε of the radome material, the thickness t of the radome 1, and the wavelength λ of the radio wave Wθ.

[0050] [Step ST2] The calculation means 202 determines the shape of the first dielectric portion 10 having a reference relative dielectric constant ε at the reference position T0 where the incident angle of the radio wave W is 0 degrees, based on the initial data taken in at step ST1.

[0051] [Step ST3] The calculation means 202 determines the shape of the second dielectric portion 11 adjacent to the first dielectric portion 10 . The second dielectric portion 11 has a dielectric constant ε that is smaller than the reference dielectric constant ε and that decreases with increasing distance from the reference position T0. θ The configuration has the following. Specifically, based on the data taken in by the input means 201 and the above-mentioned equations 1 to 7, the calculation means 202 calculates the porosity Φ of the porous body portion of the radome at which the attenuation of the radio wave Wθ becomes a minimum value according to the incident angle θ of the radio wave Wθ passing through the radome 1. θ After calculating (step ST3-1), the porosity Φ θ The amount of hollow filler to be blended to obtain the above is calculated (step ST3-2).

[0052] [Step ST4] The calculation means 202 outputs the shape data of the first dielectric portion 10 and the second dielectric portion 11 calculated in step ST3 to the 3D printer 203. As a result, the radome manufacturing system 200 according to one embodiment of the present disclosure can produce a radome 1 having porous parts (e.g., dielectric parts 11A, 11B) whose relative dielectric constants are set in stages according to the angle of incidence of the radio wave Wθ.

[0053] <Fourth embodiment> An embodiment according to the present disclosure will be described below with reference to FIG. In the method for manufacturing a radome according to this embodiment, a first dielectric part having a reference relative dielectric constant is placed at a reference position where the incident angle of radio waves transmitted or received from a communication device is 0 degrees (ST11), and a second dielectric part having a relative dielectric constant smaller than the reference relative dielectric constant and decreasing with increasing distance from the reference position is placed around the reference position (ST12).

[0054] According to the manufacturing method of the radome of this embodiment, a second dielectric portion can be provided that is located around the reference position of the first dielectric portion and has a dielectric constant that is smaller than the reference dielectric constant and that decreases with increasing distance from the reference position, thereby suppressing the attenuation of radio waves. Therefore, according to the method for manufacturing a radome according to this embodiment, it is easy to widen the range through which radio waves penetrate.

[0055] Although the present disclosure has been described above with reference to the embodiments, the present disclosure is not limited to the above-described embodiments. Various modifications that can be understood by those skilled in the art can be made to the configuration and details of the present disclosure within the scope of the present disclosure. Furthermore, each embodiment can be combined with other embodiments as appropriate.

[0056] Some or all of the above-described embodiments can be described as, but are not limited to, the following supplementary notes.

[0057] (Appendix 1) a first dielectric portion that is located at a reference position where the incident angle of a radio wave transmitted from or received by a communication device is 0 degrees and that has a reference relative dielectric constant at the reference position; a second dielectric portion located in the vicinity of the reference position, the second dielectric portion having a dielectric constant smaller than the reference dielectric constant and decreasing with increasing distance from the reference position; A radome comprising:

[0058] (Appendix 2) The second dielectric portion includes a gap for adjusting the relative dielectric constant. Radome as described in Appendix 1.

[0059] (Appendix 3) A hollow filler is disposed in the void of the second dielectric portion. 10. A radome according to any one of appendix 1 or 2.

[0060] (Appendix 4) The first dielectric portion and the second dielectric portion are integrally formed. 4. The radome according to any one of appendices 1 to 3.

[0061] (Appendix 5) The first dielectric portion and the second dielectric portion are formed in a plate shape. 5. The radome according to any one of appendices 1 to 4.

[0062] (Appendix 6) The first dielectric portion and the second dielectric portion are formed of the same material. 6. A radome according to any one of appendices 1 to 5.

[0063] (Appendix 7) the second dielectric portion has a plurality of dielectric portions, The plurality of dielectric portions have a relative dielectric constant that decreases as the dielectric portions are spaced apart from the reference position. 7. A radome according to any one of appendices 1 to 6.

[0064] (Appendix 8) The first dielectric portion and the second dielectric portion are formed so as to satisfy the relationships of the following formulas (1) to (7): 8. A radome according to any one of appendices 1 to 7.

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[0065] (Appendix 9) The first dielectric portion and the second dielectric portion are integrally formed by a 3D printer. 10. The radome according to any one of appendices 1 to 8.

[0066] (Appendix 10) the first dielectric portion and the second dielectric portion are formed as a single member as a whole, and the relative dielectric constant of the second dielectric portion is set in stages by adjusting the porosity of the porous body according to the incident angle of the radio wave. 10. The radome according to any one of appendices 1 to 9.

[0067] (Appendix 11) a first dielectric part having a reference relative dielectric constant is placed at a reference position where the incident angle of radio waves transmitted or received from the communication device is 0 degrees; a second dielectric portion having a dielectric constant smaller than the reference dielectric constant and decreasing with increasing distance from the reference position is disposed around the reference position; A method for manufacturing a radome.

[0068] (Appendix 12) The first dielectric portion and the second dielectric portion are formed so as to satisfy the relationships of the following formulas (1) to (7): 12. A method for manufacturing a radome according to claim 11.

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[0069] (Appendix 13) The first dielectric portion and the second dielectric portion are integrally formed by a 3D printer. A method for manufacturing a radome according to either appendix 11 or 12.

[0070] (Appendix 14) the second dielectric portion includes a gap for adjusting the relative dielectric constant, A method for manufacturing a radome according to any one of appendices 11 to 13.

[0071] (Appendix 15) A hollow filler is disposed in the void of the second dielectric portion. A method for manufacturing a radome according to any one of appendices 11 to 14.

[0072] (Appendix 16) The first dielectric portion and the second dielectric portion are integrally formed. A method for manufacturing a radome according to any one of appendices 11 to 15.

[0073] (Appendix 17) The first dielectric portion and the second dielectric portion are formed in a plate shape. A method for manufacturing a radome according to any one of appendices 11 to 16.

[0074] (Appendix 18) The first dielectric portion and the second dielectric portion are integrally formed from the same material. A method for manufacturing a radome according to any one of appendices 11 to 17.

[0075] (Appendix 19) the second dielectric portion has a plurality of dielectric portions, The plurality of dielectric portions have a relative dielectric constant that decreases as the dielectric portions are spaced apart from the reference position. A method for manufacturing a radome according to any one of appendices 11 to 18.

[0076] (Appendix 20) the first dielectric portion and the second dielectric portion are formed as a single member as a whole, and the relative dielectric constant of the second dielectric portion is set in stages by adjusting the porosity of the porous body according to the incident angle of the radio wave. A method for manufacturing a radome according to any one of appendices 11 to 19. [Explanation of symbols]

[0077] 1 Radome 2 Housing 3 mounting holes 10 First dielectric part 11 Second dielectric part 11A Dielectric part 11B Dielectric part 12 void 13 Porous materials 20 nozzles 21 Resin materials 22 Filler 23 Filler 100 Radome 101 first dielectric part 102 second dielectric part 200 Radome manufacturing system 201 Input Method 202 Calculation means 203 3D printer T0 reference position W0 radio wave W1 Radio Wave W2 Radio Waves W3 Radio Waves Wθ radio waves A Communication equipment C-cover

Claims

1. a first dielectric portion that is located at a reference position where the incident angle of a radio wave transmitted from or received by a communication device is 0 degrees and that has a reference relative dielectric constant at the reference position; a second dielectric portion located in the vicinity of the reference position, the second dielectric portion having a dielectric constant smaller than the reference dielectric constant and decreasing with increasing distance from the reference position; A radome comprising:

2. the second dielectric portion includes a gap for adjusting the relative dielectric constant, The radome according to claim 1 .

3. A hollow filler is disposed in the void of the second dielectric portion. The radome according to claim 2 .

4. The first dielectric portion and the second dielectric portion are integrally formed. The radome according to claim 1 .

5. The first dielectric portion and the second dielectric portion are formed in a plate shape.

5. The radome according to claim 4.

6. The first dielectric portion and the second dielectric portion are integrally formed from the same material. The radome according to claim 1 .

7. the second dielectric portion includes a plurality of dielectric portions; The plurality of dielectric portions have a relative dielectric constant that decreases as the dielectric portions are spaced apart from the reference position. The radome according to claim 1 .

8. a first dielectric part having a reference relative dielectric constant is placed at a reference position where the incident angle of radio waves transmitted or received from the communication device is 0 degrees; a second dielectric portion having a dielectric constant smaller than the reference dielectric constant and decreasing with increasing distance from the reference position is disposed around the reference position; A method for manufacturing a radome.

9. The first dielectric portion and the second dielectric portion are formed so as to satisfy the relationships of the following formulas (1) to (7): The method for manufacturing the radome according to claim 8. [Equation 1] [Equation 2] [Equation 3] [Equation 4] [Equation 5] [Equation 6] [Equation 7] However, in the formulas (1) to (7), θ: Incident angle of the radio wave incident on the radome θ': Refraction angle when the incident angle of the radio wave is θ t: thickness of the radome λ: Wavelength of the radio wave ε: the reference relative dielectric constant ε': relative dielectric constant of the porous body in the radome ε θ : relative dielectric constant of the radome through which the radio wave passes when the incident angle is θ Φ: porosity of the porous body in the radome Φ θ : porosity of the radome when the radio wave passes through at an incident angle θ

10. The first dielectric portion and the second dielectric portion are integrally formed by a 3D printer. The method for manufacturing the radome according to claim 8.

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