Manufacturing method of waveguide radar substrate

Abstract

The invention relates to the technical field of waveguide radar substrates, and discloses a waveguide radar substrate manufacturing method which comprises the steps of forming grooves in plates, electroplating the plates, combining the two plates and forming through holes. In actual use, gas contained in the waveguide cavity of the radar substrate manufactured by the method can be communicated with the outside, such as a through hole, through the sheet body made of expanded polytetrafluoroethylene, so that the waveguide cavity can be effectively prevented from being subjected to pressure damage caused by expansion with heat and contraction with cold; and external water vapor or pollutants can be blocked outside the waveguide cavity by the sheet body, so that the stability of the waveguide cavity is maintained, and the waveguide cavity is suitable for application fields with high requirements on electrical performance and harsh environmental conditions.

Description

Technical Field

[0001] The present invention relates to the technical field of waveguide radar substrates, and in particular to a method for manufacturing a waveguide radar substrate. Background Art

[0002] The radar substrate is a key component in the radar system, carrying the radar antenna and other electronic components, and has an important impact on the performance and stability of the radar.

[0003] Existing radar substrates have cavities formed inside them. The cavities can firstly suppress the propagation of surface waves generated during the operation of the radar, reduce signal interference and improve the performance of the radar; in addition, they can help to broaden the impedance bandwidth of the radar antenna, enable the radar system to operate in a wider frequency range, and improve the adaptability and flexibility of the radar system; finally, they can also optimize the electric field distribution in the radar substrate, confine the electric field to a specific area, reduce electric field leakage and interference, and improve the stability and accuracy of the radar system.

[0004] The cavity in the radar substrate is designed to be closed to avoid being affected by external moisture or pollutants. However, the gas contained in the closed cavity is isolated from the outside world, making the gas in the cavity susceptible to thermal expansion and contraction, causing pressure damage to the cavity, thereby affecting the performance of the radar substrate. Summary of the invention

[0005] In view of the shortcomings of the background technology, the present invention provides a method for manufacturing a waveguide radar substrate. The technical problem to be solved is that the cavity in the radar substrate manufactured by the existing radar substrate manufacturing method is of closed design, and the gas in the cavity is easily affected by thermal expansion and contraction to cause pressure damage to the cavity.

[0006] In order to solve the above technical problems, in the first aspect, the present invention provides the following technical solutions: a method for manufacturing a waveguide radar substrate, comprising the following steps: S1: Grooves are formed on two facing processing surfaces of two plates, respectively, and each processing surface of the plate has a first processing area and a second processing area on both sides of the groove, respectively, and a vertical distance between the second processing area and the bottom of the groove is greater than a vertical distance between the first processing area and the bottom of the groove; S2: Electroplating each plate, so that a first metal layer is formed in the first processing area of ​​the plate, a second metal layer is formed in the second processing area, and a third metal layer is formed on the wall surface of the groove; the first metal layer and the second metal layer are connected to both sides of the third metal layer; S3: Combining the two plates along the thickness direction of the plates, making the grooves on the two processed surfaces close to each other, and clamping the waterproof and breathable sheet between the first metal layers on the two processed surfaces, finally making the two second metal layers abut against each other, so that the two third metal layers and the sheet together form a waveguide cavity; S4: forming a through hole penetrating the two plates, the two first metal layers and the sheet body along the thickness direction of the plate, wherein the waveguide cavity is connected with the through hole through the sheet body.

[0007] In a certain implementation of the first aspect, the present invention further comprises step S5, which is as follows: S5: forming conductive layers on the inner wall of the through hole and on both sides of the sheet body respectively.

[0008] In a certain embodiment of the first aspect, in step S1, each of the plates includes an insulating layer having the groove formed therein, and an inner conductive layer formed on an inner surface of the insulating layer, wherein the inner conductive layer is located on the second processing area; In step S2, the first metal layer is located on the inner surface of the insulating layer, and the second metal layer is located on the inner conductive layer.

[0009] In a certain embodiment of the first aspect, the sheet body includes an inner edge defining a partial through hole and an outer edge surrounding the outside of the through hole, and a portion of the outer edge protrudes out of the adjacent third metal layer.

[0010] In a certain embodiment of the first aspect, the sheet body is circular in shape, the local protrusion distance of the outer edge is between 0.5% and 3% of the outer diameter of the sheet body, and the local part has a central angle of 20° to 35° compared to the center of the circle; the center of the sheet body is inside the through hole or outside the through hole.

[0011] In a certain embodiment of the first aspect, the sheet is made of expanded polytetrafluoroethylene, and the dielectric constant of the sheet is between 1.3 and 1.4.

[0012] In a certain embodiment of the first aspect, the thickness of the sheet body is between 18% and 30% of the height of the waveguide cavity along the thickness direction, and at least 25% of the through hole is formed on the sheet body.

[0013] In a second aspect, the present invention provides another method for manufacturing a waveguide radar substrate, comprising the following steps: S1: forming a groove in one of two facing processing surfaces of two plates, wherein the processing surface with the groove has a first processing area and a second processing area on both sides of the groove, respectively, and a vertical distance between the second processing area and the bottom of the groove is greater than a vertical distance between the first processing area and the bottom of the groove; S2: electroplating the plate with the groove, so that the plate with the groove has a first metal layer formed in the first processing area, a second metal layer formed in the second processing area, and a third metal layer formed on the wall surface of the groove; the first metal layer and the second metal layer are connected to both sides of the third metal layer; electroplating another plate to form a fourth metal layer on the processed surface of the other plate; S3: Combining two plates along the thickness direction of the plates, and clamping the waterproof and breathable sheet between the first metal layer and the fourth metal layer, finally making the second metal layer and the third metal layer abut against each other, so that the third metal layer, the part of the fourth metal layer corresponding to the third metal layer and the sheet together form a waveguide cavity; S4: forming a through hole penetrating through the two plates, the first metal layer, the fourth metal layer and the sheet body along the thickness direction of the plate, wherein the waveguide cavity is connected to the through hole through the sheet body.

[0014] In a certain implementation manner of the second aspect, step S5 is further included, and step S5 is as follows: S5: forming conductive layers on the hole walls of the through holes and on both sides of the sheet body respectively.

[0015] In a certain embodiment of the second aspect, the sheet is made of expanded polytetrafluoroethylene, the dielectric constant of the sheet is between 1.3 and 1.4, and at least 25% of the through hole is formed on the sheet.

[0016] Compared with the prior art, the present invention has the following beneficial effects: the gas contained in the waveguide cavity of the radar substrate manufactured by the method of the present invention can be connected to the outside through the sheet body made of expanded polytetrafluoroethylene, such as the through hole, so that the waveguide cavity can effectively avoid pressure damage caused by thermal expansion and contraction, and external moisture or pollutants can also be blocked outside the waveguide cavity by the sheet body, thereby maintaining the stability of the waveguide cavity, so as to be suitable for application fields with high electrical performance requirements and harsh environmental conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a flow chart of the method of the present invention in Example 1; Figure 2 It is a schematic diagram of forming a groove on a plate in Embodiment 1; Figure 3 It is a schematic diagram of electroplating a plate in Example 1; Figure 4 This is a schematic diagram of two plates before being combined in Example 1; Figure 5 This is a schematic diagram of combining two plates in Example 1; Figure 6It is a schematic diagram of forming a through hole in the first embodiment; Figure 7 for Figure 6 The schematic top view of the plate and metal coating located above is omitted; Figure 8 for Figure 7 A schematic diagram of a variation of ; Fig. 9 It is a schematic diagram of forming a conductive layer on the plate in Example 1; Fig.10 is a flow chart of the method of the present invention in Example 2; Fig.11 This is a basic schematic diagram of the waveguide radar manufactured by the method in Example 2.

[0018] Wherein: 1: plate; 1a: first plate; 10: processing surface; 11: first processing area; 12: second processing area; 13: groove; 14: insulating layer; 15: inner conductive layer; 1b: second plate; 2: metal plating; 2a: first metal plating; 21: first metal layer; 22: second metal layer; 23: third metal layer; 2b: second metal plating 3: sheet body; 31: center of circle; 32: inner edge; 33: outer edge; 331: part 4: Conductive layer; 5: Through hole; 100: waveguide radar substrate; W: width direction; T: thickness direction; C: waveguide cavity; D: outer diameter; D331: protrusion distance; σ331: center angle; T3: thickness; Hc: height. DETAILED DESCRIPTION

[0019] The following is an explanation of the implementation method of the waveguide radar substrate manufacturing method disclosed in the present invention through specific embodiments. Those skilled in the art can understand the advantages and effects of the present invention from the contents disclosed in this specification. The present invention can be implemented or applied through other different specific embodiments, and the details in this specification can also be modified and changed based on different viewpoints and applications without departing from the concept of the present invention. In addition, the drawings of the present invention are only simple schematic illustrations and are not depicted according to actual dimensions. It is stated in advance. The following embodiments will further explain the relevant technical contents of the present invention in detail, but the disclosed contents are not intended to limit the scope of protection of the present invention.

[0020] It should be understood that, although the terms first, second, third, etc. may be used herein to describe various components or features, these components or features should not be limited by these terms. These terms are mainly used to distinguish one component from another component, or one feature from another feature. In addition, the terms or used herein may include any one or more combinations of the associated listed items depending on the actual situation.

[0021] Embodiment 1 In order to effectively prevent the waveguide cavity of the waveguide radar substrate 100 from being damaged by pressure due to thermal expansion and contraction, Figure 1 As shown, this embodiment provides a method for manufacturing a waveguide radar substrate, comprising the following steps: S1: Reference Figure 2 Grooves 13 are respectively formed on two facing processing surfaces 10 of two plates 1, and the processing surface 10 of each plate 1 has a first processing area 11 and a second processing area 12 on both sides of the groove 13, and the vertical distance between the second processing area 12 and the bottom of the groove 13 is greater than the vertical distance between the first processing area 11 and the bottom of the groove 13.

[0022] In a certain embodiment, the method or structure for achieving a vertical distance between the second processing area 12 and the bottom of the groove 13 greater than the vertical distance between the first processing area 11 and the bottom of the groove 13 can be adjusted and varied according to actual needs, and the present invention is not limited thereto.

[0023] In step S1, each plate 1 includes an insulating layer 14 having a groove 13 formed therein, and an inner conductive layer 15 formed on the inner surface of the insulating layer 14, wherein the inner conductive layer 15 is located on the second processing area 12 but not on the first processing area 11, so that the second processing area 12 is higher than the first processing area 11; That is to say, the highest point of the second processing area 12 is on the inner conductive layer 15 , while the highest point of the first processing area 11 is on the inner surface of the insulating layer 14 . Therefore, the height difference between the second processing area 12 and the first processing area 11 is the thickness of the inner conductive layer 15 .

[0024] S2: Reference Figure 3 In this embodiment, each plate 1 is electroplated so that the plate 1 forms a first metal layer 21 in the first processing area 11, a second metal layer 22 in the second processing area 12, and a third metal layer 23 on the wall of the groove 13; the first metal layer 21 and the second metal layer 22 are connected to both sides of the third metal layer 23.

[0025] More specifically, in step S2, the first metal layer 21 is formed on the inner surface of the insulating layer 14, and the second metal layer 22 is formed on the inner conductive layer 15. Furthermore, the first metal layer 21, the second metal layer 22, and the third metal layer 23 formed on any one of the plates 1 may be collectively defined as a metal plating layer 2.

[0026] S3: Reference Figure 4 and Figure 5 , combine two plates 1 along the thickness direction T of the plate 1, make the grooves 13 on the two processed surfaces 10 close to each other, and clamp the waterproof and breathable sheet 3 between the first metal layers 21 on the two processed surfaces, and finally make the two second metal layers 22 abut against each other, so that the two third metal layers 23 and the sheet 3 together form a waveguide cavity C.

[0027] Specifically, in this embodiment, the sheet 3 is made of expanded polytetrafluoroethylene, which has a porous structure and has chemical stability and high temperature resistance, and the dielectric constant of the sheet is between 1.3 and 1.4.

[0028] Specifically, in this embodiment, Figure 5 , Figure 6 and Figure 7 As shown, the sheet 3 in this embodiment is a circular sheet and has a center 31, and the sheet 3 (such as: the expanded polytetrafluoroethylene sheet 3 portion sandwiched between the two first metal layers 21) has a thickness T3 along the thickness direction T, which is between 18% and 30% of a height Hc of the waveguide cavity C in the thickness direction T, but the present invention is not limited thereto. For example, in other embodiments not shown in the present invention, the sheet 3 can be non-circular according to actual needs.

[0029] S4: Reference Figure 6 A through hole 5 penetrating the two plates 1 , the two first metal layers 21 and the sheet body 3 is formed along the thickness direction T of the plate 1 , and the waveguide cavity C can only be connected to the through hole 5 through the sheet body 3 .

[0030] Accordingly, the gas contained in the waveguide cavity C can be connected to the outside through the sheet 3, so that the waveguide cavity C can effectively avoid pressure damage caused by thermal expansion and contraction, and external moisture or pollutants can also be blocked outside the waveguide cavity C by the sheet 3, thereby maintaining the stability of the waveguide cavity C, so as to be suitable for application fields with high electrical performance requirements and harsh environmental conditions.

[0031] It should be additionally noted that, in order for the sheet body 3 to provide a better technical effect of the waveguide cavity C, the sheet body 3 preferably has at least part of the following conditions, but the present invention is not limited thereto: In step S4 of this embodiment: at least 25% of the area of ​​the through hole 5 is formed on the sheet 3. For example: Figure 7As shown, the through hole 5 can be formed entirely on the sheet 3, and the center 31 of the sheet 3 is located within the through hole 5; or Figure 8 As shown, the through hole 5 may also be partially formed on the sheet body 3 , and the center 31 of the sheet body 3 is located outside the through hole 5 .

[0032] In more detail, Figure 6 As shown, the sheet 3 has an inner edge 32 defining a partial through hole 5, and an outer edge 33 surrounding the outside of the through hole 5, and a portion 331 of the outer edge 33 protrudes out of the portion of the third metal layer 23 adjacent thereto; That is, a portion 331 of the outer edge 33 of the sheet 3 is located inside the waveguide cavity C. The thickness of the portion 331 of the sheet 3 corresponding to the outer edge 33 is greater than the thickness T3 of the portion of the sheet 3 sandwiched between the two first metal layers 21 .

[0033] Furthermore, the sheet 3 has an outer diameter D, and a portion 331 of the outer edge 33 of the sheet 3 has a protrusion distance D331 along the width direction W, which is between 0.5% and 3% of the outer diameter D. The portion 331 of the outer edge 33 of the sheet 3 has a center angle σ331 between 20 degrees and 35 degrees relative to the center 31.

[0034] S5: Fig. 9 As shown, on the hole wall of the through hole 5, a conductive layer 4 is formed on both sides of the sheet 3. The conductive layer 4 is not formed on the inner edge 32 of the expanded polytetrafluoroethylene sheet 3, so that the conductive layer 4 is separated by the expanded polytetrafluoroethylene sheet 3 to form two sections separated from each other.

[0035] In combination with the above content, the gas contained in the waveguide cavity C of the waveguide radar substrate 100 manufactured by the method of the present invention can be connected to the outside through the sheet 3 made of expanded polytetrafluoroethylene, such as the through hole 5, so that the waveguide cavity C can effectively avoid pressure damage caused by thermal expansion and contraction, and external moisture or pollutants can also be blocked outside the waveguide cavity C by the sheet 3, thereby maintaining the stability of the waveguide cavity C, so as to be suitable for application fields with high electrical performance requirements and harsh environmental conditions.

[0036] Embodiment 2 like Fig.10 and 11 As shown, this embodiment provides another method for manufacturing a waveguide radar substrate, comprising the following steps: S1: A groove 13 is formed in one of two facing processing surfaces 10 of two plates 1, the plate with the groove 13 is denoted as a first plate 1a, and the other plate is denoted as a second plate 1b. The first plate 1a has a first processing area 12 and a second processing area 13 on both sides of the groove 13, respectively, and a vertical distance between the second processing area 12 and the bottom of the groove 13 is greater than a vertical distance between the first processing area 11 and the bottom of the groove 13.

[0037] In step S1, the first plate 1 includes an insulating layer 14 having a groove 13 formed therein, and an inner conductive layer 15 formed on the inner surface of the insulating layer 14, wherein the inner conductive layer 15 is located on the second processing area 12 but not on the first processing area 11 so that the second processing area 12 is higher than the first processing area 11; That is, the highest point of the second processing area 12 is on the inner conductive layer 15, and the highest point of the first processing area 11 is on the inner surface of the insulating layer 14, so the height difference between the second processing area 12 and the first processing area 11 is the thickness of the inner conductive layer 15; In addition, the processed surface of the second plate 1b is provided as an insulating layer 14 .

[0038] S2: The first plate 1a is electroplated, so that the first plate 1a has a first metal layer 22 formed in the first processing area 11, a second metal layer 22 formed in the second processing area 12, and a third metal layer 23 formed on the wall surface of the groove 13; the first metal layer 21 and the second metal layer 22 are connected to both sides of the third metal layer 23; Electroplating the second plate 1b to form a fourth metal layer 2b on the processed surface of the second plate 1b; S3: Combine two plates along the thickness direction of the plates, and clamp the waterproof and breathable sheet 3 between the first metal layer 21 and the fourth metal layer 2b, and finally make the second metal layer 22 and the third metal layer 2b abut against each other, so that the third metal layer 23, the part of the fourth metal layer 2b corresponding to the third metal layer 23 and the sheet 3 together constitute a waveguide cavity C.

[0039] Specifically, in this embodiment, the material of the sheet is expanded polytetrafluoroethylene, and the dielectric constant of the sheet is between 1.3 and 1.4.

[0040] S4: A through hole 5 is formed along the thickness direction T of the plate 1, penetrating the two plates 1, the first metal layer 21, the fourth metal layer 2b and the sheet 3, and the waveguide cavity C is connected to the through hole through the sheet 3; wherein at least 25% of the area of ​​the through hole is formed on the sheet.

[0041] S5: forming a conducting layer 4 on the hole wall of the through hole 5 and on both sides of the sheet body 3 respectively.

[0042] The above is based on the present invention as an inspiration. Through the above description, relevant staff can make various changes and modifications without departing from the technical idea of ​​this invention. The technical scope of this invention is not limited to the content in the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A method for manufacturing a waveguide radar substrate, characterized in that: The steps include: S1: Grooves (13) are formed on two facing processing surfaces (10) of two plates (1), respectively; the processing surface (10) of each plate (1) has a first processing area (11) and a second processing area (12) on both sides of the groove (13), respectively; and the vertical distance between the second processing area (12) and the bottom of the groove (13) is greater than the vertical distance between the first processing area (11) and the bottom of the groove (13); S2: electroplating each plate (1) so that the plate (1) forms a first metal layer (21) in the first processing area (11), forms a second metal layer (22) in the second processing area (12), and forms a third metal layer (23) on the wall surface of the groove (13); the first metal layer (21) and the second metal layer (22) are connected to both sides of the third metal layer (23); S3: combining two plates (1) along the thickness direction of the plates (1) so that the grooves (13) on the two processed surfaces (10) are close to each other, and the waterproof and breathable sheet (3) is clamped between the first metal layers (21) on the two processed surfaces (10), and finally the two second metal layers (22) are abutted against each other, so that the two third metal layers (23) and the sheet (3) together form a waveguide cavity; S4: A through hole (5) is formed along the thickness direction of the plate (1) and penetrates the two plates (1), the two first metal layers (21) and the sheet body (1), and the waveguide cavity is connected to the through hole (5) through the sheet body (3).

2. The method for manufacturing a waveguide radar substrate according to claim 1, characterized in that: The step S5 is further included, and the step S5 is as follows: S5: forming a conducting layer (4) on the hole wall of the through hole (5) and on both sides of the sheet body (3).

3. The method for manufacturing a waveguide radar substrate according to claim 1, characterized in that: In step S1, each of the plates (1) comprises an insulating layer (14) formed with the groove (13), and an inner conductive layer (15) formed on the inner surface of the insulating layer (14), wherein the inner conductive layer (15) is located on the second processing area (12); In step S2, the first metal layer (21) is located on the inner surface of the insulating layer (14), and the second metal layer (22) is located on the inner conductive layer (15).

4. The method for manufacturing a waveguide radar substrate according to claim 1, characterized in that: The sheet body (3) comprises an inner edge (32) defining a partial through hole (5) and an outer edge (33) surrounding the outside of the through hole (5), wherein a portion (331) of the outer edge (33) protrudes out of an adjacent third metal layer (23).

5. The method for manufacturing a waveguide radar substrate according to claim 4, characterized in that: The sheet body (3) is circular in shape, a protrusion distance of a portion (331) of the outer edge (33) is between 0.5% and 3% of the outer diameter of the sheet body (3), and the portion (331) has a central angle of 20° to 35° compared to the center (31) of the sheet body (3); the center (31) of the sheet body (3) is inside the through hole (5) or outside the through hole (5).

6. A method for manufacturing a waveguide radar substrate according to claim 1, 4 or 5, characterized in that: The sheet body (3) is made of expanded polytetrafluoroethylene, and the dielectric constant of the sheet body (3) is between 1.3 and 1.

4.

7. The method for manufacturing a waveguide radar substrate according to claim 1, characterized in that: The thickness of the sheet body (3) is between 18% and 30% of the height of the waveguide cavity along the thickness direction, and at least 25% of the area of ​​the through hole (5) is formed on the sheet body (3).

8. A method for manufacturing a waveguide radar substrate, characterized in that: The steps include: S1: A groove (13) is formed in one of two facing processing surfaces (10) of two plates (1), the processing surface (10) having the groove (13) having a first processing area (11) and a second processing area (12) on both sides of the groove (13), respectively, and a vertical distance between the second processing area (12) and the bottom of the groove (13) is greater than a vertical distance between the first processing area (12) and the bottom of the groove (13); S2: electroplating the plate (1) with the groove (13) so that the plate (1) with the groove (13) forms a first metal layer (21) in the first processing area (11), a second metal layer (22) in the second processing area (12), and a third metal layer (23) on the wall surface of the groove (13); the first metal layer (21) and the second metal layer (22) are connected to both sides of the third metal layer (23); electroplating another plate (1) to form a fourth metal layer (2b) on the processing surface of the other plate (1); S3: combining two plates (1) along the thickness direction of the plates (1), and clamping a waterproof and breathable sheet (3) between the first metal layer (21) and the fourth metal layer (2b), finally making the second metal layer (22) and the third metal layer (2b) abut against each other, so that the third metal layer (23), a portion of the fourth metal layer (2b) corresponding to the third metal layer (23), and the sheet (3) together form a waveguide cavity; S4: A through hole (5) is formed along the thickness direction of the plate (1) and penetrates the two plates (1), the first metal layer (21), the fourth metal layer (2b) and the sheet body (1); the waveguide cavity is connected to the through hole (5) through the sheet body (3).

9. The method for manufacturing a waveguide radar substrate according to claim 8, characterized in that: The step S5 is further included, and the step S5 is as follows: S5: forming a conducting layer (4) on the hole wall of the through hole (5) and on both sides of the sheet body (3).

10. The method for manufacturing a waveguide radar substrate according to claim 9, characterized in that: The sheet body (3) is made of expanded polytetrafluoroethylene, the dielectric constant of the sheet body (3) is between 1.3 and 1.4, and at least 25% of the area of ​​the through hole (5) is formed on the sheet body (3).

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