JP2009246953A - Chip antenna and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a chip antenna manufactured in high accuracy with wider angle-measuring coverage, and to provide its manufacturing method. <P>SOLUTION: The chip antenna 100 has a structure with an antenna element 101 and a reflection board 102 integrally fixed by an antenna fixture 110 and mounted on a ground plate 103. The antenna element 101 is formed in a configuration with an antenna radiator 101a and an antenna stand 101b bent at a right angle, and with the antenna radiator 101a arranged on the upper surface of the antenna fixture 110. The antenna radiator 101a is disposed in parallel to the ground plate 103 and separated by a second distance L from it. The antenna stand 101b has a lower end 101c externally exposed through inside of the antenna fixture 110, and bent at the right angle. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a chip antenna and a manufacturing method thereof, and more particularly to a technical field of a chip antenna having a wide-angle directivity used in an on-vehicle radar device and a manufacturing method thereof.

  Among the conventionally known antennas, a half-wave dipole antenna is known as an antenna having the lowest directivity or omnidirectionality. The half-wave dipole antenna is an antenna formed by arranging two linear antenna elements on a straight line, and has an antenna pattern having a donut-like gain in a direction orthogonal to the antenna elements.

  In addition, as a similar to a half-wave dipole antenna, a quarter-wave monopole formed by using only one of two antenna elements of a dipole and vertically arranging it on a conductor plate (ground plate). Antennas are also known. In a 1/4 wavelength monopole antenna, a mirror image of a 1/4 wavelength antenna element arranged on a conductor plate is obtained at a symmetrical position with respect to the conductor plate, and the conductor plate is infinitely wide. The ¼ wavelength monopole antenna and its mirror image provide exactly the same characteristics as the half-wave dipole antenna.

  Such a dipole antenna or monopole antenna has been widely used as an omnidirectional antenna. For example, a monopole antenna is widely used as an antenna installed on the roof of an automobile or as an antenna for a mobile phone. It is used. As a form of actually using a monopole antenna, for example, a structure in which a central conductor of a coaxial line is an antenna element and an external conductor is connected to a ground plane is widely used.

  On the other hand, as a radar device that is mounted on an automobile and detects an obstacle or the like in the traveling direction, an apparatus that measures an azimuth angle of an obstacle or the like by arranging a plurality of antennas is conventionally known. For example, in the radar apparatus antenna 900 shown in FIG. 9 disclosed in Patent Document 1, an array antenna is formed by arranging a plurality of antenna units 902 in which antenna elements 901 are spirally formed on a ground plane 903. And the antenna which detects the azimuth of an obstruction using this is disclosed.

JP 2006-258762 A

  However, the antenna described in Patent Document 1 has problems in characteristics and manufacturing method. In terms of characteristics, there is a problem that directivity is strong, azimuth angle can be measured only in an angular range limited to the direction perpendicular to the antenna surface (for example, about ± 30 degrees), and so-called angular coverage is narrow. It was. In order to use such an antenna for radar applications, it is necessary to change the directivity of the antenna, for example, and a circuit or mechanical means for that purpose is required. On the other hand, in order to widen the range of angle measurement (angle measurement), it is preferable to use an antenna with a wide directivity. However, for example, with a dipole antenna or a monopole antenna, the direction cannot be specified due to non-directionality. There is.

  Further, as a problem in the manufacturing method, a radio wave in a high frequency band with a short wavelength is used in the antenna for the radar device. However, when the wavelength becomes short, it is necessary to manufacture the antenna structure with high accuracy. The antenna described in Patent Document 1 also has a fine structure, but its manufacturing method is not disclosed. There is a need for a manufacturing method capable of manufacturing an antenna having a fine structure with high accuracy and capable of mass production.

  Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a chip antenna having a wide angular coverage and manufactured with high accuracy, and a manufacturing method thereof.

  According to a first aspect of the chip antenna of the present invention, there is provided a planar substrate, a ground plate installed on one surface of the substrate, a reflective plate erected perpendicularly to the ground plate, and a first from the reflective plate. An antenna standing portion erected in a direction perpendicular to the ground plane at a position separated by a distance and an antenna radiation bent in a direction perpendicular to the reflector at a second distance from the ground plane An antenna element having an antenna part, a feed line disposed on the other surface of the substrate, and an antenna fixing unit that fixes the antenna standing part and the reflector integrally by disposing the antenna radiation part on an upper surface. The antenna fixing portion is disposed on the ground plane, the lower end of the antenna standing portion and the lower end of the reflector plate are exposed from the bottom surface of the antenna fixing portion, and the antenna standing portion is connected to the feed line. Electrically connected Plate is electrically connected to said base plate, wherein the one or more dummy pads on the bottom surface of the antenna fixing portion is connected to said ground plane is provided.

  According to another aspect of the chip antenna of the present invention, the convex portion formed on the antenna fixing portion has a cross section of any one of a square shape, a polygonal shape, and a circular shape and the length is equal to or greater than the thickness of the substrate. The through hole formed in the ground plate and the substrate is fitted from the ground plate side, and the antenna standing portion is located at the center of the through hole formed in the ground plate.

  Another aspect of the chip antenna of the present invention is characterized in that the antenna element has a dimension determined based on a frequency to be used.

  In another aspect of the chip antenna of the present invention, the frequency to be used is a quasi-millimeter wave band, and the cross section of the convex portion and one side or diameter of the through hole are formed to be approximately 1 mm or less. And

  In another aspect of the chip antenna of the present invention, the antenna fixing portion has a hollow portion at a position shorter than the second distance in the direction of the ground plane from the antenna radiation portion, and the dummy pad is formed in the hollow portion. It arrange | positions and it is connected to the said ground plane, It is characterized by the above-mentioned.

  In another aspect of the chip antenna of the present invention, the antenna fixing portion fixes the ground plane section in a non-contact manner with the antenna standing portion at a position away from the antenna radiating portion in the direction of the ground plane by the second distance. And the ground plane piece is electrically connected to the ground plane.

  In another aspect of the chip antenna of the present invention, the ground plane piece has another through hole that extends to the lower end of the reflective plate and is drilled at the same position as the through hole. It is electrically connected.

  In another aspect of the chip antenna of the present invention, the lower end of the antenna standing portion is bent at a right angle on the bottom surface of the antenna fixing portion and is electrically connected to the feed line or formed on the feed line. The through-holes are linearly extended and electrically connected to the feed line.

  In another aspect of the chip antenna of the present invention, the lower end of the reflector is bent at a right angle on the bottom surface of the antenna fixing portion and is electrically connected to the ground plane, or is a straight line formed in the ground plane. It is inserted into the groove and electrically connected.

  Another aspect of the chip antenna of the present invention is characterized in that an array antenna is formed by arranging a plurality of the antenna elements integrated with the antenna fixing portion and the reflection plate on one surface side of the substrate. And

  Another aspect of the chip antenna of the present invention is characterized in that lower ends of the antenna standing portions of the plurality of antenna elements are electrically connected to the feed line, respectively.

  A first aspect of a method for manufacturing a chip antenna according to the present invention includes: a planar substrate; a ground plate installed on one surface of the substrate; a reflective plate erected vertically to the ground plate; and the reflective plate An antenna standing portion erected in a direction perpendicular to the ground plane at a position away from the ground plane by a distance from the antenna, and bent in a direction perpendicular to the reflector at a second distance from the ground plane. An antenna element having an antenna radiating portion; a feed line disposed on the other surface of the substrate; and the antenna radiating portion disposed on the upper surface to integrally fix the antenna standing portion and the reflecting plate. An antenna fixing part, and a first antenna plate formed for the antenna element and a second conductor plate formed for the reflector plate. Fixed to a predetermined mold separated by a first distance, A resin having a predetermined dielectric constant is injected into a mold to form the antenna fixing portion, a predetermined metal is plated on the bottom surface of the antenna fixing portion to form one or more dummy pads, and the lower end of the antenna fixing portion is A through hole to be fitted is formed in the ground plate and the substrate, and a lower end of the antenna fixing portion is fitted from the ground plate side to the through hole so that a lower end of the antenna standing portion is on the other surface side of the substrate. Passing through, electrically connecting between the lower end of the antenna standing portion and the feeder line, and between the lower end of the reflector and the ground plane, respectively, and connecting between the dummy pad and the ground plane It is characterized by.

  In another aspect of the chip antenna manufacturing method of the present invention, the mold is used to form a hollow portion at a position shorter than the second distance in the lower end direction of the antenna standing portion from the antenna radiating portion. An antenna fixing part is formed, and the dummy pad is formed in the hollow part.

  In another aspect of the chip antenna manufacturing method of the present invention, the first antenna is disposed at a predetermined position of the mold separated from the antenna radiating portion by the second distance in the direction of the lower end of the antenna standing portion. After further fixing the third conductor plate for the ground plane slice in which the through hole is drilled at the same position and size as the through hole of the substrate in a non-contact manner with the conductor plate, the resin is injected to make the antenna fixing portion It is characterized by forming.

  Another aspect of the chip antenna manufacturing method of the present invention is characterized in that the third conductor plate is extended to the lower end of the second conductor plate and connected thereto.

  As described above, according to the present invention, the antenna element and the reflector are integrated and arranged on the ground plane, so that the chip antenna having a wide angular coverage and manufactured with high accuracy and the manufacturing method thereof are provided. Can be provided. According to the present invention, mass production of a chip antenna can be easily performed.

1 is a perspective view, a plan view, and a cross-sectional view of a chip antenna according to a first embodiment of the present invention. It is a perspective view of the radiation | emission surface of an array antenna. It is a perspective view by the side of the feed line of an array antenna. It is sectional drawing which shows the flow of the process of the manufacturing method of the chip antenna which concerns on embodiment of this invention. It is the perspective view of the chip antenna which concerns on 2nd Embodiment, a top view, and sectional drawing. It is the top view and sectional drawing of the chip antenna which concern on 3rd Embodiment. It is a perspective view of the chip antenna concerning a 4th embodiment. It is a perspective view of the array antenna using the chip antenna of a 1st embodiment. It is a top view which shows the conventional antenna for radar apparatuses.

  A chip antenna and a manufacturing method thereof according to a preferred embodiment of the present invention will be described in detail with reference to the drawings. Each component having the same function is denoted by the same reference numeral for simplification of illustration and description.

  As an example of an antenna for a radar apparatus, an array antenna shown in the perspective views of FIGS. 2 and 3 can be considered. FIG. 2 is a perspective view of a radiation surface of the array antenna 10, and FIG. 3 is a perspective view of a surface opposite to the radiation surface. The radiation surface of the array antenna 10 is configured such that a plurality of antenna elements 101 and a reflecting plate 102 are arranged on the ground plate 103 as an antenna unit 11. The reflection plate 102 is electrically connected to the ground plate 103.

  In addition, a feed line 105 connected to each antenna element 101 is formed on the substrate 104 on the other surface of the array antenna 10. The feed line 105 forms a microstrip line with the ground plane 103 and the substrate 104.

  The chip antenna of the present invention can be used for the antenna unit 11 used for the array antenna 10. A chip antenna according to a first embodiment of the present invention will be described with reference to FIG. 1A is a perspective view, FIG. 1B is a plan view, FIG. 1C is a cross-sectional view taken along line AA in the plan view, and FIG. 1D is a cross-sectional view taken along line BB in the plan view. Each figure is shown.

  As shown in FIG. 1, the chip antenna 100 according to the present embodiment has a configuration in which an antenna element 101 and a reflector 102 are integrally fixed by an antenna fixing portion 110 and arranged on a ground plane 103. The antenna element 101 is formed in a shape in which an antenna radiating portion 101 a and an antenna standing portion 101 b are bent at a right angle, and the antenna radiating portion 101 a is disposed on the upper surface of the antenna fixing portion 110. The antenna radiating portion 101a is arranged in parallel to the ground plane 103 and separated from the ground plate 103 by a second distance L. In addition, the antenna standing portion 101b has a lower end portion 101c that penetrates the inside of the antenna fixing portion 110 and is exposed to the outside and is bent at a right angle. When the antenna standing portion 101b is connected to the electric line through a through hole, the antenna standing portion 101b may be linear without being bent. By arranging the antenna element 101, the reflecting plate 102, and the ground plane 103 as described above, a chip antenna having a wide angular coverage can be manufactured.

  The reflecting plate 102 is disposed inside the antenna fixing portion 110 in parallel with the antenna standing portion 101b. The reflector 102 is disposed at a position separated from the antenna standing portion 101b by the first distance D. The upper end portion 102a of the reflector 102 is configured such that the surface on the antenna element 101 side is exposed outside the antenna fixing portion 110 and faces the end portion of the antenna radiating portion 101a. The lower end portion 102b of the reflecting plate 102 is exposed outside the antenna fixing portion 110 and bent at a right angle. Alternatively, a linear groove may be formed in the ground plate 103, and the lower end portion 102b of the reflecting plate 102 may be inserted into the groove so as to be electrically connected.

  In the antenna fixing part 110, a part fixing the lower end of the antenna standing part 101b protrudes to form a convex part 111. The convex portion 111 has a cross section formed in any one of a square shape, a polygonal shape, and a circular shape, and has a length equal to or greater than the thickness of the substrate 104. When the chip antenna 100 of this embodiment is used in the quasi-millimeter wave band, one side or the diameter of the cross section of the convex portion 111 is formed to be approximately 1 mm or less. The convex portion 111 is fitted from the base plate 103 side into a through hole 154 formed in the base plate 104 and the base plate 103 so that the antenna standing portion 101 b and the base plate 103 are not in contact with each other. The antenna standing portion 101b is located at the center of the through hole formed in the ground plate 103. As shown in FIG. 1C, both sides of the antenna standing portion 101b and the through hole 154 formed in the ground plate 103 are provided. A through hole 154 is formed so that distances E and F with the surface are equal. The lower end portion 101c of the antenna element 101 is exposed outside the antenna fixing portion 110 and bent at a right angle. A first indentation 112 is formed on the left side of the lower end of the antenna fixing unit 110 located below the antenna radiating unit 101a, and a second indentation 113 is formed on the right side of the lower end of the antenna fixing unit 110. .

  The distance L1 from the antenna radiating portion 101a to the first depression 112 is shorter than the second distance L, and a gap is formed between the first depression 112 and the ground plane 103. Similarly, the 2nd hollow part 113 is formed so that a clearance gap may be formed also between the 2nd hollow part 113 and the ground plane 103. FIG. Dummy pads 114 provided to fix the chip antenna are provided in the gap between the first depression 112 and the ground plane 103 and the gap between the second depression 113 and the ground plane 103, respectively. . The dummy pads 114 are provided at the left and right ends of the first dent 112 and the second dent 113 (FIG. 1B). The dummy pad 114 is preferably provided at a position away from directly below the antenna radiating portion 101 a so as not to affect the radiation characteristics of the antenna element 101.

  As described above, the antenna fixing portion 110 that integrally fixes the antenna element 101 and the reflecting plate 102 is placed and fixed on the ground plate 103. A through-hole 154 for inserting the convex portion 111 of the antenna fixing portion 110 is formed in the ground plate 103 and the substrate 104. By inserting the convex portion 111 into this, the lower end portion 101c of the antenna element 101 is connected to the feed line. It protrudes to the 105 side. The antenna fixing unit 110 connects the dummy pad 114 to the ground plate 103 with solder 120, solder-connects the tip of the lower end portion 101c of the antenna element 101 to the feed line 105, and further connects the tip of the lower end portion 102b of the reflector 102 to the ground plate 103. It is fixed by soldering.

  The size of the first hollow portion 112 is determined so that the ground plane 103 is disposed as much as possible under the antenna radiating portion 101a. That is, the depth of the recessed portion 112 is made as large as possible so that the ground plane 103 is disposed below the antenna radiating portion 101a over most of the length. In addition, the height of the recesses 112 and 113 is set to a height suitable for forming the dummy pad 114.

  As described above, the chip antenna 100 according to the present embodiment includes the antenna element 101 and the reflector 102 that are integrally fixed by the antenna fixing portion 110 that is injection-molded using a mold. The interval with the reflecting plate 102 is positioned with high accuracy, and the interval is maintained with high accuracy even after being arranged on the ground plate 103. The distance between the antenna element 101 and the reflecting plate 102 is set to about 0.25 mm, for example, and it is necessary to mold and maintain this with an accuracy of (0.25 ± 0.05) mm. In the present embodiment, this is realized by forming the antenna fixing portion 110.

  Next, an embodiment of the chip antenna manufacturing method of the present invention will be described. Hereinafter, a method for manufacturing the antenna chip 100 according to the first embodiment will be described with reference to FIGS. FIG. 4 is a cross-sectional view showing the flow of steps of the chip antenna manufacturing method of the present embodiment. 4A is a cross-sectional view of the mold cut at a position corresponding to the line AA in FIG. 1B, and FIG. 4B shows the molded antenna fixing portion 110 along the line BB in FIG. 4C is a cross-sectional view taken along line AA in FIG. 1B, and FIG. 4D is an antenna fixing portion 110 taken along line AA in FIG. 1B. FIG. 4E is a cross-sectional view of the antenna fixing unit 110, the base plate 103, and the substrate 104 taken along line BB of FIG. 1B.

  In the manufacturing method of this embodiment, the first conductor plate formed in the shape of the antenna element 101 is formed on the mold 151 (151a to 151d) formed in the shape of the antenna fixing portion 110 in FIG. 152 and the second conductor plate 153 formed in the shape of the reflecting plate 102 are fixed. At this time, the first conductor plate 152 and the second conductor plate 153 are positioned with high accuracy so that the distance between them is a predetermined size. Thereafter, the mold 151 is sealed and a resin having a predetermined dielectric constant is injected inside. As a result, the antenna fixing portion 110 is formed in which the antenna element 101 and the reflection plate 102 are positioned with high accuracy and incorporated. By using the mold 151, the convex portion 111, the first hollow portion 112, and the second hollow portion 113 can be easily formed in the antenna fixing portion 110. The first conductor plate 152 and the second conductor plate 153 are preferably copper plates from the viewpoint of conductivity, but the conductor plates 152 and 153 are not limited to copper plates.

  In FIG. 4B of the next step, one or more dummy pads 114 are formed by plating a predetermined metal on the bottom surfaces of the first hollow portion 112 and the second hollow portion 113 of the molded antenna fixing portion 110. Form. Here, three dummy pads 114 are provided on each of the left and right ends of the bottom surface of the first recess 112. The dummy pad 114 is preferably provided at a position away from directly below the antenna radiating portion 101 a so as not to affect the radiation characteristics of the antenna element 101.

  In FIG. 4C of the next step, a through hole 154 for fitting the convex portion 111 of the antenna fixing portion 110 to the ground plane 103 and the substrate 104 is formed. The through hole 154a of the ground plate 103 is formed to be larger than the through hole 154b of the substrate 104 so as to be connected to the reflecting plate 102 so as not to contact the antenna standing portion 101b, and further to be easily connected to the lower end portion 102b of the reflecting plate 102. Formed. The through hole 154b of the substrate 104 is formed in a shape in which the convex portion 111 of the antenna fixing portion 110 and the antenna standing portion 101b can be inserted. In addition, although the process of forming the through-hole 154 needs to be performed before the process of fitting the antenna fixing | fixed part 110, it does not necessarily need to be at this stage.

  In FIG. 4D of the next step, the antenna fixing portion 110 is placed on the ground plate 103, and the convex portion 111 is inserted into the through hole 154 to be fitted. Thereby, the lower end 101c of the antenna element 101 is penetrated to the substrate 104 side. Further, in FIG. 4E of the next step, the dummy pad 114 and the ground plane 103 are connected with the solder 120, the lower end portion 101 c of the antenna element 101 and the feeder line 105, and the lower end portion of the reflection plate 102. The solder 120 is also connected between 102b and the ground plane 102. For the connection using the solder 120, for example, a method similar to component mounting on a printed circuit board, such as applying paste solder to at least one of the connection objects and passing through a reflow furnace, can be applied. Note that an adhesive or the like may be used instead of the solder 120 connection. In the case of using an adhesive or the like, electrical conductivity is required at the connection point, such as between the lower end portion 101c of the antenna element 101 and the feeder line 105, and between the lower end portion 102b of the reflection plate 102 and the ground plane 102. In this case, it is desirable to use a conductive adhesive or the like. Further, the connection using the solder 120 and the connection using an adhesive or the like can be used in combination.

  According to the manufacturing method of the present embodiment described above, the distance between the antenna element 101 and the reflecting plate 102 can be positioned with high accuracy, and this can be maintained with high accuracy. Moreover, since the space | interval of the antenna radiation | emission part 101a and the ground plane 103 is determined and maintained with high precision by the antenna fixing | fixed part 110, a radiation characteristic is also maintained with high precision. Furthermore, by using the mold 151, mass production of the chip antenna 100 is facilitated.

  A chip antenna according to a second embodiment of the present invention will be described with reference to FIG. 5A is a perspective view, FIG. 5B is a plan view, FIG. 5C is a cross-sectional view taken along line AA in the plan view, and FIG. 5D is a cross-sectional view taken along line BB in the plan view. Each figure is shown.

  The chip antenna 200 of this embodiment further includes a ground plane piece 220 in the antenna fixing portion 210. The ground plane slice 220 is disposed at a position away from the antenna radiating portion 101 a by the second distance L, and a part thereof is exposed to the first recess 212. When the antenna fixing portion 210 is placed and fixed on the ground plane 103, the exposed portion of the ground plane section 220 is soldered to the ground plane 103 and contributes to the antenna characteristics as a part of the ground plane 103.

  In the chip antenna 200 of the present embodiment, the width of the ground plane piece 220 is made smaller than the width of the antenna fixing portion 210 in order to provide the dummy pads 114 on both the left and right sides of the first hollow portion 212.

  In the chip antenna 200 of the present embodiment, since the ground plane disposed below the antenna radiating portion 101a is integrally fixed to the antenna fixing portion 210 as the ground plane slice 220, the antenna radiating portion 101a and the ground plane slice 220 are separated from each other. The interval can be accurately positioned at the second distance and can be maintained.

  The chip antenna 200 of this embodiment can be manufactured by the same method as the manufacturing method described with reference to FIG. When the chip antenna 200 is manufactured, in FIG. 4A, in addition to the first conductor plate 152 for forming the antenna element 101 and the second conductor plate 153 for forming the reflecting plate 102. Then, the third conductor plate for forming the base plate piece 220 is positioned with high accuracy and fixed to a predetermined mold. Thereafter, by injecting a predetermined resin into the mold, the antenna fixing portion 210 in which the antenna element 101, the reflecting plate 102, and the ground plane piece 220 are fixed integrally is manufactured.

  Since the convex portion 211 at the lower part of the antenna fixing portion 210 of the present embodiment is different in shape and size from the convex portion 111 of the first embodiment, the through holes formed in the ground plane 103 and the substrate 104 are also convex. It is necessary to form according to the part 211. After the antenna fixing portion 210 is placed on the ground plane 103, between the dummy pad 114 and the ground plane 103, between the lower end portion 101c of the antenna element 101 and the feed line 105, the lower end portion 102b of the reflector 102 and the ground plane 102. And between the ground plane piece 220 and the ground plane 103 with solder 120.

  A chip antenna according to a third embodiment of the present invention will be described with reference to FIG. FIG. 6 shows (a) a plan view, (b) a sectional view taken along line AA in the plan view, and (c) a sectional view taken along line BB in the plan view, for the chip antenna 300 of the present embodiment. .

  The chip antenna 300 according to the present embodiment further includes a ground plane section 320 in the antenna fixing portion 310, as with the chip antenna 200 according to the second embodiment. However, in the present embodiment, the ground plane piece 320 has the same width as the antenna fixing portion 310, and no space for arranging the dummy pads 114 is provided on the left and right sides of the first recess 312.

  In the present embodiment, the dummy pad 114 is provided only in the second depression 313 and is not provided on the first depression 312 side. As a means for fixing the first hollow portion 312 side to the ground plane 103, the periphery of the portion exposed from the antenna fixing portion 310 of the ground plane section 320 can be firmly fixed to the ground plane 103 by soldering.

  Also in the chip antenna 300 of the embodiment, the ground plate disposed below the antenna radiating portion 101 a is integrally fixed to the antenna fixing portion 310 as the ground plate slice 320, and thus the distance between the antenna radiating portion 101 a and the ground plane slice 320. Can be positioned with high accuracy at the second distance, and this can be maintained. Further, the ground plane piece 320 can be arranged in most of the longitudinal direction of the antenna radiating portion 101a. Thereby, a suitable radiation characteristic is obtained.

  In the second embodiment and the third embodiment, the ground plane section 220 and the ground plane section 320 are built in the antenna fixing portions 210 and 310, respectively, but this is extended to the lower end portion 102b of the reflector 102 to be electrically connected. You may make it connect to. That is, a conductor plate in which the ground plane piece 220 or 320 and the reflection plate 103 are integrally formed can be used.

  Further, the antenna element 101 and the reflector 102 of the chip antenna shown in the first to third embodiments of the present invention can be substituted by a group of conduction holes in which through holes are continuous. FIG. 7 is a perspective view illustrating an example of a chip antenna 400 according to the fourth embodiment. The chip antenna 400 of this embodiment includes an antenna element 401 in which a through hole 401a is disposed between an upper conductor piece 401b and a lower conductor piece 401c instead of the antenna element 101, and the upper part is replaced with the reflector 102. The reflector 402 has a plurality of through holes 402a arranged between the conductor piece 402b and the lower conductor piece 402c. In FIG. 7, the convex portion 411, the first concave portion 412, the second concave portion 413, and the dummy pad 414 are respectively the convex portion 111, the first concave portion 112, and the second concave portion 113 in FIG. Corresponds to the dummy pad 114.

  As described with reference to FIG. 4, the chip antenna 100 according to the first embodiment is formed by insert injection molding after fixing the first conductive plate 152 and the second conductive plate 153 to the mold 151. An antenna element 101 and a reflecting plate 102 are formed. The antenna standing portion 101b and the reflector 102 of the antenna element 101 are disposed so as to vertically penetrate the antenna fixing portion 110. However, insert injection molding in such a vertical direction may be difficult. Even in the chip antennas 200 and 300 of the second embodiment and the third embodiment, insert injection molding in the vertical direction may be similarly difficult.

  Therefore, a through hole can be used instead of the conductor plate in the vertical direction like the antenna element 401 and the reflector 402 of the chip antenna 400 of the present embodiment. In the present embodiment, an antenna element 401 having a through hole 401a is provided instead of the antenna element 101, and a reflector 402 having a through hole 402a is provided instead of the reflector 102. Further, the antenna standing portion 101b can be formed by a through hole.

  The antenna element 401 and the reflector 402 used in this embodiment can be formed as follows. Hereinafter, the manufacturing method of the reflector 402 will be mainly described. For example, in the chip antenna manufacturing method shown in FIG. 4, copper foils corresponding to the upper conductor piece 402b and the lower conductor piece 402c are formed at predetermined positions on the molds 151a and 151c formed in the shape of the antenna fixing portion 410. A predetermined number of precision pins are arranged at positions where the through holes 402a are formed. Thereafter, the mold 151 is sealed and a resin having a predetermined dielectric constant is injected inside. As a result, a group of conduction holes is formed between the upper conductor piece 402b and the lower conductor piece 402c.

  After the conduction hole is formed as described above, a conductor layer is formed on the inner wall of the conduction hole by plating. As a result, a through hole 402a is produced in which the conductor layer formed on the inner wall of the conduction hole is electrically connected to the upper conductor piece 402b and the lower conductor piece 402c. Depending on the frequency to be used, in the case of the quasi-millimeter wave band, as the reflector 402 used in the present embodiment, for example, the diameter of the through holes 402a is φ0.3 mm, and the interval between the through holes 402a is 0.65 mm or less. Is good. The diameter of the through-hole 401a of the antenna element 401 may be φ0.3 mm, similar to the diameter of the through-hole 402a, but it is desirable that it is determined based on actually required antenna characteristics.

  In addition, in the manufacturing method of the reflector 402 described above, the fixing portion 410 having a plurality of conduction holes is formed by insert injection molding after fixing a predetermined number of precision pins to the mold. By injection molding using such a precision pin, it is possible to form the through holes 401a and 402a with high accuracy.

  As another method for forming the through holes 401a and 402a, it is also possible to use a method in which the fixing portion 410 is injection-molded without placing a precision pin, and thereafter drilling and plating are performed. For example, as the drilling process, after the copper foils corresponding to the upper conductor piece 402b and the lower conductor piece 402c are arranged and injection-molded, the through-hole 402a can be drilled by machining such as a drilling machine. Further, the conductor plate may be attached later to a predetermined portion of the antenna fixing portion 410 that is injection-molded.

  An embodiment in which an array antenna is manufactured using the chip antenna of the present invention is shown in FIG. FIG. 8 is a perspective view of the array antenna 500 of the present embodiment. Any of the chip antennas 100, 200, 300, and 400 of the above embodiment may be used as the array antenna 500. In the following description, it is assumed that the chip antenna 100 of the first embodiment is used.

  The array antenna 500 is configured by arranging a plurality of antenna fixing portions 110 on the ground plane 103, and a plurality of chip antennas 100 are formed. The antenna fixing portions 110 are all arranged in the same direction, and all the antenna elements 101 have a wide angular coverage. The feed line 105 shown in FIG. 3 is routed on the opposite surface of the array antenna 500. The lower end portion 101c of the antenna element 101 is connected to each end portion of the feed line 105. The direction in which the lower end portion 101c of the antenna element 101 is bent at a right angle can be determined according to the orientation of the end portion of the feed line 105. it can.

  In the array antenna 500 of the present embodiment, eight chip antennas 100 are arranged in a 2 × 4 array, and an array antenna having a wide angular coverage is provided as an antenna for a radar apparatus that measures an azimuth angle. be able to.

  Note that the description in the present embodiment shows an example of the chip antenna and the manufacturing method thereof according to the present invention, and the present invention is not limited to this. The detailed configuration and detailed operation of the chip antenna and the manufacturing method thereof in the present embodiment can be appropriately changed without departing from the spirit of the present invention.

10 Array antenna 11 Antenna unit 100, 200, 300, 400 Chip antenna 101, 401 Antenna element 102 Reflector plate 103 Ground plate 104 Substrate 105 Feed line 110, 210, 310, 410 Antenna fixing part 111, 211, 311, 411 Protrusion part 112 212, 312, 412 First depression 113, 213, 313, 413 Second depression 114, 414 Dummy pad 120 Solder 151 Mold 152, 153 Conductor plate 154 Through hole 220, 320 Base plate slice 401a, 402a Through hole 402 Reflector 500 Array antenna

Claims (15)

A planar substrate;
A ground plane installed on one side of the substrate;
A reflector vertically installed on the ground plane;
An antenna standing portion erected in a direction perpendicular to the ground plane at a position away from the reflector by a first distance and a direction perpendicular to the reflector at a second distance from the ground plane An antenna element having an antenna radiation portion bent into
A feed line disposed on the other surface of the substrate;
An antenna fixing part that arranges the antenna radiating part on an upper surface and fixes the antenna standing part and the reflector integrally;
The antenna fixing portion is disposed on the ground plane, the lower end of the antenna standing portion and the lower end of the reflector are exposed from the bottom surface of the antenna fixing portion, and the antenna standing portion is electrically connected to the feed line, The chip antenna according to claim 1, wherein the reflector is electrically connected to the ground plane, and one or more dummy pads are provided on a bottom surface of the antenna fixing portion to be connected to the ground plane. Protrusions formed on the antenna fixing portion so that the length of the cross section is any one of a square, a polygon, and a circle are equal to or greater than the thickness of the substrate, and the through-hole formed in the ground plate and the substrate. It is fitted into the hole from the base plate side,
The chip antenna according to claim 1, wherein the antenna standing portion is located at a center of a through hole formed in the ground plane. The chip antenna according to claim 2, wherein the antenna element has a dimension determined based on a frequency to be used. The frequency used is a quasi-millimeter wave band,
4. The chip antenna according to claim 3, wherein a cross section of the convex portion and one side or diameter of the through hole are formed to be approximately 1 mm or less. The antenna fixing part has a hollow part at a position shorter than the second distance in the direction of the ground plane from the antenna radiating part,
5. The chip antenna according to claim 1, wherein the dummy pad is disposed in the recess and connected to the ground plane. 6. The antenna fixing portion has a ground plane section fixed in a non-contact manner with the antenna standing portion at a position away from the antenna radiation portion in the direction of the ground plane by the second distance;
The chip antenna according to any one of claims 1 to 3, wherein the ground plane piece is electrically connected to the ground plane. The ground plane piece has another through-hole that extends to the lower end of the reflecting plate and is drilled with the same size at the same position as the through-hole, and is electrically connected to the reflecting plate. The chip antenna according to claim 6. The lower end of the antenna standing part is bent at a right angle on the bottom surface of the antenna fixing part and is electrically connected to the feed line, or is linearly extended to a through-hole formed in the feed line. The chip antenna according to claim 1, wherein the chip antenna is electrically connected to a feed line. The lower end of the reflecting plate is bent at a right angle on the bottom surface of the antenna fixing portion and is electrically connected to the ground plate, or is inserted through a linear groove formed in the ground plate and electrically connected. The chip antenna according to any one of claims 1 to 8, wherein the chip antenna is provided. The array antenna is formed by arranging a plurality of the antenna elements and the reflection plates integrated on the antenna fixing portion on one surface side of the substrate. The chip antenna according to item. 11. The chip antenna according to claim 10, wherein lower ends of the antenna standing portions of the plurality of antenna elements are electrically connected to the feed line, respectively. A planar substrate, a ground plate installed on one surface of the substrate, a reflector plate standing vertically to the ground plate, and perpendicular to the ground plate at a first distance from the reflector plate An antenna element having an antenna erection part erected in the direction to be and an antenna radiation part bent in a direction perpendicular to the reflector at a second distance from the ground plane, and the other of the substrates A chip antenna comprising: a feeder line disposed on a surface of the antenna; and an antenna fixing portion that integrally arranges the antenna standing portion and the reflector by arranging the antenna radiating portion on an upper surface. There,
The first conductor plate formed for the antenna element and the second conductor plate formed for the reflector are separated by the first distance and fixed to a predetermined mold, and the mold The antenna fixing portion is formed by injecting resin having a predetermined dielectric constant to
Plating a predetermined metal on the bottom surface of the antenna fixing portion to form one or more dummy pads;
A through hole for fitting the lower end of the antenna fixing portion is formed in the base plate and the substrate;
The lower end of the antenna fixing portion is fitted into the through hole from the ground plane side, and the lower end of the antenna standing portion is penetrated to the other surface side of the substrate,
Electrically connecting the lower end of the antenna standing portion and the feeder line, and the lower end of the reflector and the ground plate, respectively, and connecting the dummy pad and the ground plate, A method for manufacturing a chip antenna. Forming the antenna fixing part in a shape having a hollow part at a position shorter than the second distance in the lower end direction of the antenna standing part from the antenna radiating part using the mold;
The method of manufacturing a chip antenna according to claim 12, wherein the dummy pad is formed in the recess. Same as the through hole of the substrate at a predetermined position of the mold away from the antenna radiating portion in the direction of the lower end of the antenna standing portion by the second distance in a non-contact manner with the first conductor plate 14. The chip according to claim 13, wherein the antenna fixing portion is formed by injecting the resin after further fixing the third conductor plate for the ground plane section having a through-hole formed at a position and a size. Antenna manufacturing method. 15. The method of manufacturing a chip antenna according to claim 14, wherein the third conductor plate is extended to a lower end of the second conductor plate and connected thereto.

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