JP6059779B1 - Dipole antenna and manufacturing method thereof - Google Patents

Abstract

A dipole antenna capable of changing characteristic impedance without greatly changing a resonance frequency is realized. A first element 11 having a first feeding point P provided at an end thereof, a second feeding point Q provided in an intermediate portion, and the second feeding point Q being a first feeding point P. The second element 12 is arranged to be divided into a radiating portion 12a and a matching portion 12b by a second feeding point Q, and the second element 12 is arranged so as to face the matching portion 12b. At least a part of the first element 11 is running in parallel. [Selection] Figure 1

Description

  The present invention relates to a dipole antenna having two elements. Moreover, it is related with the manufacturing method of such a dipole antenna.

  With the widespread use of electronic devices having a wireless communication function, various antennas suitable for mounting on such electronic devices are being developed. For example, a monopole antenna composed of an element (linear or strip conductor) and a ground (planar conductor) can be mounted on a dielectric substrate such as a flexible printed circuit board. Is suitable. A dipole antenna constituted by two elements (linear or strip conductors) is also suitable for mounting on an electronic device for the same reason.

  By the way, in the antenna design, in addition to making the resonance frequency coincide with the frequency of the electromagnetic wave to be transmitted / received, it is important to make the characteristic impedance coincide with the characteristic impedance of the feed line. However, when the shape of the element is changed so as to make the characteristic impedance coincide with a desired value, the resonance frequency often deviates from the desired value, which increases the difficulty in antenna design.

  As an antenna in which such a problem is considered, for example, an antenna device described in Patent Document 1 is known. The antenna device described in Patent Document 1 is an antenna including an antenna element (corresponding to the element described above) and a ground part (corresponding to the ground described above). This antenna device employs a configuration in which the adjustment element branched from the antenna element is capacitively coupled to the ground portion, and the characteristic impedance can be changed without greatly changing the resonance frequency by changing the length of the adjustment element. It is possible to make it.

JP2013-21418 (release date: January 31, 2013)

  However, the antenna device described in Patent Document 1 is a monopole antenna that requires a ground having a certain area or more. For this reason, the antenna mounted on the electronic device is required to be reduced in size and weight, but the antenna device described in Patent Document 1 has a problem that it is difficult to meet this requirement.

  The present invention has been made in view of the above problems, and an object thereof is to realize a structure capable of changing the characteristic impedance without greatly changing the resonance frequency in a dipole antenna that does not require a ground. There is.

  The dipole antenna according to the present invention includes a first element having a first feeding point at an end portion, a second feeding point at an intermediate portion, and the second feeding point serving as the first feeding point. A second element arranged to face the point, and the second element is divided into a radiation part and a matching part by the second feeding point, and at least one of the matching parts The part is running in parallel with the first element.

  The dipole antenna configured as described above has a resonance frequency corresponding to the sum of the length of the first element and the length of the radiating portion of the second element (hereinafter referred to as “element length”). . Therefore, by appropriately changing the element length, the resonance frequency of the dipole antenna configured as described above can be matched with a desired frequency. More specifically, the resonant frequency of the dipole antenna can be matched with the desired frequency by setting the element length to about ½ of the wavelength corresponding to the desired frequency.

  Further, according to the above configuration, since at least a part of the alignment portion runs in parallel with the first element, the alignment portion and the first element are interposed between the alignment portion and the first element. A capacity corresponding to the length of the section in which the element runs in parallel (hereinafter referred to as “parallel running section length”) is generated. For this reason, the dipole antenna comprised as mentioned above has the characteristic impedance according to the said parallel running area length. Therefore, the characteristic impedance of the dipole antenna can be matched with a desired impedance (for example, the characteristic impedance of a coaxial cable) by appropriately changing the parallel section length.

  Thus, in the dipole antenna, the adjustment of the resonance frequency by changing the element length and the adjustment of the characteristic impedance by changing the parallel running section length can be performed independently of each other. Therefore, by changing the parallel section length without changing the element length, the characteristic impedance of the dipole antenna can be changed without greatly changing the resonance frequency of the dipole antenna.

  In the dipole antenna according to the present invention, the first element includes a linear portion extending in a first direction from the first feeding point, and the matching portion starts from the second feeding point. A first straight line portion extending in a second direction orthogonal to the first direction, and a second straight line portion starting from the end of the first straight line portion and extending in the first direction. It is preferable that it is comprised.

  According to said structure, the length of the said parallel running area can be changed by changing the length of a said 2nd linear part. Therefore, the characteristic impedance of the dipole antenna can be matched with a desired impedance by appropriately changing the length of the second linear portion of the matching portion. That is, the adjustment of the characteristic impedance in the dipole antenna can be further facilitated.

  In the dipole antenna according to the present invention, the length of the section in which the second straight portion of the matching portion and the first element run side by side is not less than 1/2 of the length of the first element. It is preferable that it is 3 or less.

  According to said structure, even if the length of the said 2nd linear part of the said matching part is changed, the resonant frequency of the said dipole antenna hardly changes. Therefore, the characteristic impedance of the dipole antenna is changed almost without changing the resonance frequency of the dipole antenna by changing the length of the second linear portion of the matching portion without changing the element length. be able to. That is, the adjustment of the characteristic impedance in the dipole antenna can be further facilitated.

  In the dipole antenna according to the present invention, the radiating portion starts from the second feeding point, starts with a first straight portion extending in a direction opposite to the second direction, and ends with the first straight portion. And the second straight portion extending in the first direction.

  According to the above configuration, in addition to the second linear portion of the alignment portion, the second linear portion of the radiating portion runs in parallel with the first element. In addition to the element, a capacitance is generated between the radiating portion and the first element. For this reason, the capacitance generated between the first element and the second element is increased as compared with the case where only the second linear portion of the radiating portion runs in parallel with the first element. Can do. Thereby, the adjustment range of the characteristic impedance of the dipole antenna can be expanded as compared with the case where only the second linear portion of the radiating portion runs in parallel with the first element.

  Moreover, according to said structure, the said 1st element, the said 2nd straight part of the said matching part, and the said 2nd straight part of the said radiation | emission part comprise a coplanar transmission line. For this reason, the high-frequency current input to the first element via the first feeding point is likely to flow in the first direction, and as a result, a straight line having the first direction as the vibration direction of the electric field. Polarized waves are efficiently radiated from the dipole antenna.

  In the dipole antenna according to the present invention, the radiating portion has the first straight portion, the second straight portion, and the end of the second straight portion as a starting end, and is opposite to the second direction. It is preferable that the first linear portion extends and the fourth linear portion starts from the end of the third linear portion and extends in the direction opposite to the first direction.

  According to said structure, the area | region required for arrangement | positioning of the said radiation | emission part can be narrowed, without shortening the said element length. That is, the dipole antenna can be reduced in size without shifting the resonance frequency of the dipole antenna to the high frequency side.

  In the dipole antenna according to the present invention, it is preferable that the radiating portion is constituted by a linear portion starting from the second feeding point and extending in a direction opposite to the second direction.

  According to said structure, the radiation gain of the said dipole antenna can be enlarged compared with the case where the said radiation | emission part is bent.

  In the method of manufacturing the dipole antenna, the step of setting the length of the section in which the first element and the matching portion run side by side so that the characteristic impedance of the dipole antenna matches the characteristic impedance of the feed line A manufacturing method including the above is also included in the scope of the present invention.

  According to the present invention, in a dipole antenna that does not require a ground, the characteristic impedance can be changed without greatly changing the resonance frequency. That is, an antenna capable of changing the characteristic impedance without greatly changing the resonance frequency can be realized smaller and lighter than the antenna device described in Patent Document 1.

(A) is a top view of the dipole antenna which concerns on the 1st Embodiment of this invention. (B) is sectional drawing of the dipole antenna shown to (a). It is a graph which shows the frequency characteristic of the dipole antenna shown in FIG. The solid line shows the frequency dependence of VSWR, and the dotted line shows the frequency dependence of the average radiation gain. It is a graph which shows the radiation pattern of the dipole antenna shown in FIG. (A) shows the radiation pattern in the yz plane, (b) shows the radiation pattern in the xy plane, and (c) shows the radiation pattern in the zx plane. It is a graph which shows the frequency characteristic of the dipole antenna shown in FIG. The frequency dependence of VSWR obtained when the parallel section length L is 1/3, 1/2, 2/3, 5/6 of the length L1 of the first element is shown. It is a top view of the dipole antenna which concerns on the 2nd Embodiment of this invention. It is a graph which shows the frequency characteristic of the dipole antenna shown in FIG. The solid line shows the frequency dependence of VSWR, and the dotted line shows the frequency dependence of the average radiation gain.

<< First Embodiment >>
The dipole antenna according to the first embodiment of the present invention will be described below with reference to the drawings.

[Configuration of dipole antenna]
First, the configuration of the dipole antenna 1 according to the present embodiment will be described with reference to FIG. 1A is a plan view of the dipole antenna 1, and FIG. 1B is a cross-sectional view taken along the line AA ′ of the dipole antenna 1.

  As shown in FIG. 1A, the dipole antenna 1 is a planar dipole antenna including two elements 11 and 12 that are insulated from each other. In the present embodiment, these two elements 11 and 12 are bonded and fixed to one surface of the dielectric substrate 2 as shown in FIG.

  The first element 11 is a strip-shaped conductor provided with a first feeding point P at one end, and its length L1 is determined according to the frequency of the electromagnetic wave to be transmitted and received. For example, a signal line of a feed line (for example, an inner conductor of a coaxial cable) is connected to the first feed point P. In the present embodiment, as the first element 11, a strip-shaped conductor that extends linearly from the first feeding point P in the y-axis negative direction (“first direction” in the claims) in the illustrated coordinate system. Is used.

  The second element 12 is a belt-like conductor that is provided with a second feeding point Q in the middle, and is arranged so that the second feeding point Q faces the first feeding point P. To the second feeding point Q, a ground line of the feeding line (for example, an outer conductor of a coaxial cable) is connected. The second element 12 is divided into a radiating portion 12a and a matching portion 12b by the second feeding point Q.

  The radiating portion 12a is a portion that assumes a radiation function in the second element 12, and its length L2 is determined according to the frequency of the electromagnetic wave to be transmitted and received. In the present embodiment, a bent strip conductor is used as the radiating portion 12a. More specifically, a first straight portion 12a1, a first corner portion 12a2, a second straight portion 12a3, a second corner portion 12a4, a third straight portion 12a5, and a third corner portion described below. A band-shaped conductor constituted by 12a6 and the fourth straight portion 12a7 is used.

  The first straight line portion 12a1 is a strip-shaped conductor starting from the second feeding point Q and ending at the first corner portion 12a2. The first linear portion 12a1 is a negative conductor in the x-axis negative direction (“first” in the claims). It extends in the direction opposite to the direction of 2)). The first corner portion 12a2 is a rectangular conductor having a side having the same length as the width of the first straight portion 12a1 and a side having the same length as the width of the second straight portion 12a3.

  The second straight line portion 12a3 is a strip-shaped conductor having a first corner portion 12a2 as a starting end and a second corner portion 12a4 as a terminal end. In the illustrated coordinate system, the second straight portion 12a3 is in the y-axis negative direction ( 1) ”). The second corner portion 12a4 is a rectangular conductor having a side having the same length as the width of the second straight portion 12a3 and a side having the same length as the width of the third straight portion 12a5.

  The third straight line portion 12a5 is a strip-shaped conductor having a second corner portion 12a4 as a starting end and a third corner portion 12a6 as a terminal end. In the illustrated coordinate system, the third straight portion 12a5 is in the x-axis negative direction ( It extends in the direction opposite to the direction of 2)). The third corner portion 12a6 is a rectangular conductor having a side having the same length as the width of the third straight portion 12a5 and a side having the same length as the width of the fourth straight portion 12a7.

  The fourth linear portion 12a7 is a strip-like conductor starting from the third corner portion 12a6, and extends in the y-axis positive direction ("the direction opposite to the first direction" in the claims) in the illustrated coordinate system. . The terminal end of the fourth straight part 12a7 is open.

  In addition, when the shape of the radiation | emission part 12a is the strip | belt-shaped conductor which consists of a some linear part, the length L2 of the radiation | emission part 12a is given by the sum of the length of each linear part. If it says according to the example shown in figure, the length L2 of the radiation | emission part 12a will be L2 = L21 (length of the 1st linear part 12a1) + L22 (length of the 2nd linear part 12a3) + L23 (3rd The length of the straight portion 12a5) + L24 (the length of the fourth straight portion 12a7).

  The matching portion 12 b is a portion that assumes a matching function in the second element 12, and at least a part thereof is configured to run in parallel with the first element 11. In the present embodiment, a T-shaped strip conductor is used as the matching portion 12b. More specifically, a belt-like conductor constituted by a first straight portion 12b1, a branch portion 12b2, a second straight portion 12b3, and a third straight portion 12b4 described below is used.

  The first straight line portion 12b1 is a strip-shaped conductor having a second feeding point Q as a starting end and a branching portion 12b2 as a terminating end. In the illustrated coordinate system, the first straight portion 12b1 is in the positive x-axis direction from the second feeding point Q (claimed). In the range of “second direction”). The branch portion 12b2 is a rectangular conductor having sides having the same length as the width of the first straight portion 12b1 and sides having the same length as the widths of the second straight portion 12b3 and the third straight portion 12b4.

  The second straight portion 12b3 is a strip-shaped conductor starting from the branch portion 12b2, and extends in the negative y-axis direction (the “first direction” in the claims) in the illustrated coordinate system. The terminal end of the second straight portion 12b3 is open.

  The third straight portion 12b4 is a strip-shaped conductor that terminates in the branch portion 12b2, and extends in the positive y-axis direction in the illustrated coordinate system. The terminal end of the third straight portion 12b4 is open.

  The dipole antenna 1 configured as described above corresponds to the sum (hereinafter referred to as “element length”) L0 of the length L1 of the first element 11 and the length L2 of the radiating portion 12a of the second element 12. Have a resonant frequency. Therefore, by appropriately changing the element length L0, the resonance frequency of the dipole antenna 1 can be matched with the desired frequency f (the frequency of the electromagnetic wave to be transmitted / received by the dipole antenna 1). More specifically, the resonant frequency of the dipole antenna 1 can be matched with the desired frequency f by setting the element length L0 to about ½ of the wavelength λ corresponding to the desired frequency f.

  When the dipole antenna 1 is disposed in free space, the free space wavelength λo given by λo [m] = c [m / s] / f [1 / s] is the wavelength λ corresponding to the frequency f. . On the other hand, when the dipole antenna 1 is disposed in a dielectric (including the case where the dipole antenna 1 is formed on the surface of the dielectric substrate 2 as in this embodiment), the wavelength is expected to be shortened by the dielectric. However, a wavelength shorter than the free space wavelength λo is the wavelength λ corresponding to the frequency f.

  In the dipole antenna 1, since at least a part of the matching portion 12 b runs in parallel with the first element 11, the matching portion 12 b and the first element 11 are interposed between the matching portion 12 b and the first element 11. A capacity corresponding to the length of the section in which the two run in parallel (hereinafter referred to as “parallel section length”) L occurs. For this reason, the dipole antenna 1 has a characteristic impedance corresponding to the parallel section length L. Therefore, the characteristic impedance of the dipole antenna 1 can be matched with a desired impedance (for example, the characteristic impedance of the feed line) by appropriately changing the parallel section length L.

  Thus, the resonance frequency of the dipole antenna 1 can be adjusted by changing the element length L0, and the characteristic impedance of the dipole antenna 1 can be adjusted by changing the parallel section length L. Therefore, by changing the parallel running section length L without changing the element length L0, the characteristic impedance of the dipole antenna 1 can be changed without greatly changing the resonance frequency of the dipole antenna 1.

  In addition, as shown to Fig.1 (a), the alignment part 12b is a 1st linear part 12b1 extended in the x-axis positive direction from the 2nd feeding point Q, and the y-axis negative direction from the terminal of the 1st linear part 12b1 If the second linear portion 12b3 extending in the direction is included, the characteristic impedance of the dipole antenna 1 can be adjusted more easily. This is because the parallel running section length L can be changed, that is, the characteristic impedance of the dipole antenna 1 can be changed only by changing the length of the second straight portion 12b3.

  Further, as shown in FIG. 1A, the radiating portion 12a has a first straight line portion 12a1 extending in the negative x-axis direction from the second feeding point Q and a negative end direction of the first straight line portion 12a1 in the negative y-axis direction. In this case, the adjustment range of the characteristic impedance of the dipole antenna 1 can be expanded. This is because a capacitance is generated between the radiating portion 12 a and the first element 11 in addition to the alignment portion 12 b and the first element 11, and therefore, between the first element 11 and the second element 12. This is because the capacity generated in the case becomes large.

  In this case, linearly polarized waves having the y-axis direction as the electric field vibration direction can be efficiently radiated from the dipole antenna 1. This is because the coplanar transmission path is configured by the three elements of the first element 11, the second linear portion 12a3 of the radiating portion 12a, and the second linear portion 12b3 of the matching portion 12b. This is because the high-frequency current input to the first element 11 through the first element 11 easily flows in the y-axis direction.

  Further, when the radiating portion 12a is a bent strip-shaped conductor as shown in FIG. 1A, the dipole antenna 1 can be miniaturized without shifting the resonance frequency of the dipole antenna 1 to the high frequency side. Can do. This is because the area required for the arrangement of the radiating portion 12a can be narrowed without shortening the entire length of the radiating portion 12a.

[Characteristics of antenna]
Next, the characteristics of the dipole antenna 1 according to this embodiment will be described with reference to FIGS.

  The characteristics shown in FIGS. 2 and 3 are obtained when the dipole antenna 1 in which the dimensions of the respective parts are set as follows is formed on the surface of the dielectric substrate 2 of 28.8 mm × 9.9 mm. is there. The characteristic shown in FIG. 4 is that the dipole antenna 1 in which the dimensions of each part are set as follows except for the length of the second straight part 12b3 and the parallel running section length L of the matching part 12b is 28.8 mm × 9. This is a characteristic obtained when formed on the surface of a 9 mm dielectric substrate 2.

Length of first element 11 (L1): 20.5 mm
Radiation portion 12a of second element 12
Length of first straight part 12a1 (L21): 0.75mm
Length of second straight part 12a3 (L22): 17.00 mm
Length of third straight line portion 12a5 (L23): 1.00mm
Length (L24) of fourth linear portion 12a7: 17.25 mm
Matching portion 12b of second element 12
Length of the first straight part 12b1: 1.5mm
Length of second straight part 12b3: 11.5mm
The length of the third straight part 12b4: 2.0 mm
Parallel section length L: 10.5mm.

  The dipole antenna 1 is intended for transmission and reception of electromagnetic waves belonging to the 2.4 GHz band (2412 MHz to 2484 MHz). However, the element length L0 (the sum of the length L1 of the first element 11 and the length L2 of the radiating portion 12a of the second element 12) is assumed to be shortened by the dielectric substrate 2, and the center frequency is 2448 MHz. Is set to 56.5 mm corresponding to about 92% of 1/2 of the free space wavelength λo≈122.5 mm.

  FIG. 2 is a graph showing the frequency characteristics of the dipole antenna 1. In FIG. 2, the solid line indicates the frequency dependency of VSRW (Voltage Standing Wave Ratio), and the dotted line indicates the frequency dependency of the average radiation gain. The following can be confirmed from the graph shown in FIG.

  (1) The VSWR of the dipole antenna 1 takes a minimum value in the 2.4 GHz band. That is, the dipole antenna 1 has a resonance frequency in the 2.4 GHz band.

  (2) The average radiation gain of the dipole antenna 1 exceeds −4 dB in the 2.4 GHz band. That is, the dipole antenna 1 has an average radiation gain sufficient for practical use in the 2.4 GHz band.

  FIG. 3 is a graph showing a radiation pattern (direction dependency of a radiation electric field) of the dipole antenna 1 at 2412 MHz. 3, (a) shows the radiation pattern on the yz plane, (b) shows the radiation pattern on the xy plane, and (c) shows the radiation pattern on the zx plane (for the definition of the coordinate system, See FIG. 1). The following can be confirmed from the graph shown in FIG.

  (1) The radiation pattern of the dipole antenna 1 is more omnidirectional than the radiation pattern of the standard dipole antenna (eight-shaped radiation pattern).

  (2) Regarding the radiation pattern on the yz plane, the radiation field in the positive z-axis direction has an Eθ component that is overwhelmingly larger than the Eφ component (Eθ >> Eφ). That is, the electromagnetic waves radiated from the dipole antenna 1 in the positive z-axis direction are linearly polarized waves having the y-axis direction as the electric field vibration direction.

  FIG. 4 shows that by changing the length of the second linear portion 12b3 of the alignment portion 12b, the parallel running section length L is reduced to 1/3, 1/2, 2/3 of the length L1 of the first element 11. It is a graph which shows the frequency dependence of VSWR obtained when it is set to 5/6. The following can be confirmed from the graph shown in FIG.

  (1) Even if the parallel running section length L is changed, the resonance frequency of the dipole antenna 1 does not change greatly. That is, the adjustment of the characteristic impedance by changing the parallel running section length L can be performed without greatly changing the resonance frequency.

  (2) When the parallel running section length L is changed within the range of (1/2) × L1 ≦ L ≦ (2/3) × L1, the resonance frequency of the dipole antenna 1 hardly changes. That is, the adjustment of the characteristic impedance by changing the parallel running section length L within the above range can be performed with almost no change in the resonance frequency.

<< Second Embodiment >>
A dipole antenna according to the second embodiment of the present invention will be described below with reference to the drawings.

[Configuration of dipole antenna]
First, the configuration of the dipole antenna 1 ′ according to this embodiment will be described with reference to FIG. FIG. 5 is a plan view of a dipole antenna 1 ′ according to this modification.

  As shown in FIG. 5, the dipole antenna 1 ′ according to the present embodiment is the same as the dipole antenna 1 according to the first embodiment (see FIG. 1). It is replaced by a radiating portion 12a ′ made of a strip-like conductor extending linearly (“the direction opposite to the second direction” in the claims). About the other structure, it is the same as that of the dipole antenna 1 which concerns on 1st Embodiment.

  Also in the dipole antenna 1 ′ according to the present embodiment, the resonance frequency can be adjusted by changing the element length L0 = L1 + L2, and the characteristic impedance can be adjusted by changing the parallel section length L. it can. Therefore, also in the dipole antenna 1 'according to the present embodiment, the characteristic impedance can be changed without greatly changing the resonance frequency by changing the parallel section length L without changing the element length L0.

[Characteristics of dipole antenna]
Next, the characteristics of the dipole antenna 1 ′ according to this embodiment will be described with reference to FIG. FIG. 6 is a graph showing frequency characteristics of the dipole antenna 1 ′.

  In FIG. 6, the solid line indicates the frequency dependence of the VSRW, and the dotted line indicates the frequency dependence of the average radiation gain. The following can be confirmed from the graph shown in FIG.

  (1) The VSWR of the dipole antenna 1 'takes a minimum value in the 2.4 GHz band. That is, the dipole antenna 1 has a resonance frequency in the 2.4 GHz band.

  (2) The average radiation gain of the dipole antenna 1 ′ exceeds −2 dB in the 2.4 GHz band. That is, the dipole antenna 1 ′ having the radiating portion 12 a ′ made of a straight strip conductor has a higher average radiation gain than the dipole antenna 1 having the radiating portion 12 a made of a bent strip conductor.

≪Additional notes≫
The present invention is not limited to the above-described embodiments, and various modifications are possible within the scope shown in the claims, and embodiments obtained by appropriately combining technical means disclosed in different embodiments. Is also included in the technical scope of the present invention. Furthermore, a new technical feature can be formed by combining the technical means disclosed in each embodiment.

  The present invention can be suitably applied to a dipole antenna for mounting on various electronic devices, in particular, a printed dipole antenna formed on the surface of a flexible printed board.

DESCRIPTION OF SYMBOLS 1 Dipole antenna 11 1st element 12 2nd element 12a Radiation part 12a1 1st straight line part 12a3 2nd straight line part 12a5 3rd straight line part 12a7 4th straight line part 12b Matching part 12b1 1st straight line part 12b3 Second straight part

Claims (6)

A first element provided with a first feeding point at an end;
A second feeding point is provided in the middle part, and the second feeding point is arranged so that the second feeding point faces the first feeding point, and
The first element is composed of a linear portion extending in the first direction from the first feeding point,
Said second element, said being divided into a matching section and the radiating portion by the second feed point, at least a portion of the matching section are run in parallel with the first element,
The radiating portion starts from the second feeding point, starts from a first straight portion extending in a direction opposite to the second direction orthogonal to the first direction, and starts from the end of the first straight portion. A second straight line portion extending in the first direction, a third straight line portion starting from an end of the second straight line portion and extending in a direction opposite to the second direction, and the third straight line portion. And a fourth straight portion extending in a direction opposite to the first direction, with the terminal end of
A dipole antenna characterized by that. The matching unit is to the second feeding point and the starting end, and a first linear portion extending upward Symbol second direction, the end of the first straight portion and the starting end, first extends in the first direction 2 straight portions, and
The dipole antenna according to claim 1. The length of the section in which the second straight portion of the alignment portion and the first element run in parallel is ½ or more and 2/3 or less of the length of the first element.
The dipole antenna according to claim 2. A first element provided with a first feeding point at an end;
A second feeding point is provided in the middle part, and the second feeding point is arranged so that the second feeding point faces the first feeding point, and
The first element is composed of a linear portion extending in the first direction from the first feeding point,
The second element is divided into a radiating portion and a matching portion by the second feeding point, and at least a part of the matching portion runs in parallel with the first element,
The radiating portion is configured by a linear portion that starts from the second feeding point and extends in a direction opposite to the second direction orthogonal to the first direction.
Features and be holder Lee pole antenna that.   The matching section starts from the second feeding point and extends in the second direction, and the second straight line extends in the first direction starting from the end of the first straight line. A linear portion of, and
The dipole antenna according to claim 4. In the manufacturing method of the dipole antenna which manufactures the dipole antenna of any one of Claims 1-5 ,
Including a step of setting a length of a section in which the first element and the matching portion run in parallel so that the characteristic impedance of the dipole antenna matches the characteristic impedance of the feed line.
A method for manufacturing a dipole antenna.

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