WO2010023752A1 - Elongated antenna - Google Patents

Elongated antenna Download PDF

Info

Publication number
WO2010023752A1
WO2010023752A1 PCT/JP2008/065546 JP2008065546W WO2010023752A1 WO 2010023752 A1 WO2010023752 A1 WO 2010023752A1 JP 2008065546 W JP2008065546 W JP 2008065546W WO 2010023752 A1 WO2010023752 A1 WO 2010023752A1
Authority
WO
WIPO (PCT)
Prior art keywords
antenna
base material
power feeding
longitudinal
outer peripheral
Prior art date
Application number
PCT/JP2008/065546
Other languages
French (fr)
Japanese (ja)
Inventor
雅美 鈴木
智之 藤枝
Original Assignee
パイオニア株式会社
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by パイオニア株式会社 filed Critical パイオニア株式会社
Priority to PCT/JP2008/065546 priority Critical patent/WO2010023752A1/en
Priority to JP2010526472A priority patent/JPWO2010023752A1/en
Priority to EP08809613A priority patent/EP2330686A1/en
Publication of WO2010023752A1 publication Critical patent/WO2010023752A1/en

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q9/00—Electrically-short antennas having dimensions not more than twice the operating wavelength and consisting of conductive active radiating elements
    • H01Q9/04—Resonant antennas
    • H01Q9/16—Resonant antennas with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole
    • H01Q9/26—Resonant antennas with feed intermediate between the extremities of the antenna, e.g. centre-fed dipole with folded element or elements, the folded parts being spaced apart a small fraction of operating wavelength
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/36—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith
    • H01Q1/38—Structural form of radiating elements, e.g. cone, spiral, umbrella; Particular materials used therewith formed by a conductive layer on an insulating support
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/40—Radiating elements coated with or embedded in protective material

Definitions

  • the present invention relates to a small antenna.
  • film antennas are often used as terrestrial digital broadcast receiving antennas in vehicles.
  • Patent Documents 1 and 2 describe examples of small antennas used for mobile phones and the like.
  • the longitudinal antenna according to the first aspect of the present invention has a longitudinal shape and is at least in contact with the first base material having a different dielectric constant between the outer peripheral portion and the central portion, and the outer peripheral portion of the first base material. And it is provided with the feed element arrange
  • a longitudinal antenna according to a preferred embodiment of the present invention has a longitudinal shape, and is at least in contact with a first base material having a different permittivity between an outer peripheral portion and a central portion, and an outer peripheral portion of the first base material. And a power feeding element disposed along the shape of the outer peripheral portion, and a non-excitation element disposed close to the power feeding element.
  • the first base material is made of a dielectric material such as ceramic, and the outer peripheral portion and the central portion have different dielectric constants.
  • the power feeding element is at least partially in contact with the outer peripheral portion, and is disposed along the shape of the outer peripheral portion. And a non-excitation element is arrange
  • the power feeding element is disposed on the outer peripheral portion of the base material, that is, outside the central portion of the base material.
  • the power feeding part and the tip of the power feeding element come close to each other, and electromagnetic coupling may occur between them.
  • the dielectric constant of the center portion of the base material interposed between the power feeding portion and the power feeding element is different from that of the outer peripheral portion, such electromagnetic coupling can be suppressed.
  • the dielectric constant at the center of the substrate is preferably smaller than the dielectric constant at the outer periphery.
  • the central portion of the first base material is hollowed out. Therefore, the presence of air in the central portion suppresses electromagnetic coupling between the power feeding portion and the tip portion of the power feeding element.
  • the first base material has a slot-shaped planar shape in which only the central portion is cut out.
  • the first base material has a C-shaped planar shape in which a part of the outer peripheral portion at the center in the longitudinal direction is further cut.
  • the feeding element has a width of a portion in contact with the outer peripheral portion in the short direction of the first base material, and the outer periphery in the longitudinal direction of the first base material. It is larger than the width of the part in contact with the part.
  • the feeding element has a plurality of portions in contact with the outer peripheral portion in the short direction of the first base material.
  • the longitudinal antenna includes a second base material having a dielectric constant lower than a dielectric constant of an outer peripheral portion of the first base material, and the feed element and the non-excitation element include the first base 2 base materials.
  • the feeding element and the non-excitation element are formed on the second base material, and the dielectric base material is disposed thereon. If a feed element or a non-excitation element is formed on a dielectric substrate, the manufacturing cost increases. By forming the power feeding element and the non-excitation element on the second base material, the manufacturing cost can be reduced.
  • the feeding portion of the feeding element and the two end portions of the feeding element are arranged to face each other in the vicinity of the center position in the longitudinal direction of the second base material. ing.
  • electromagnetic coupling is likely to occur between the feeding portion and the two end portions of the feeding element, but such a coupling is effective because the dielectric constant of the central portion of the substrate is different from that of the outer peripheral portion. To be suppressed.
  • the power feeding element is in contact with the first base material in the vicinity of two ends of the power feeding element or in a place excluding the vicinity of the power feeding part.
  • the longitudinal antenna is enclosed in a resin case.
  • corrosion of conductor parts such as a feed element and a non-excitation element, can be prevented.
  • the above longitudinal antenna is disposed close to a dielectric having an area larger than the area of the first base material.
  • the resonance frequency of the antenna can be lowered, and the antenna can be downsized accordingly.
  • FIG. 1A is a perspective view of an antenna according to the first embodiment.
  • the antenna 100 includes a longitudinal base 1, a feed element 2, and a non-excitation element 3.
  • the length and width of the feed element 2 and the non-excitation element 3 and the length, width, and thickness of the base material 1 are determined so that terrestrial digital broadcasting can be received satisfactorily.
  • the substrate 1 has a longitudinal shape (plate shape, stick shape) and is made of a dielectric material such as ceramic.
  • the dielectric constant of the substrate 1 is about 20
  • the length of the substrate 1 is about 100 to 150 mm
  • the thickness of the substrate 1 is about 3 to 5 mm.
  • the center part of the base material 1 is hollowed out in a rectangular shape, and a cutout part 1c is provided. Moreover, the substantially center part in the longitudinal direction of the base material 1 is cut
  • the cut-out portion 1c corresponds to the “center portion” of the base material in the present invention, and the portion of the base material 1 on the outer periphery of the cut-out portion 1c corresponds to the “outer peripheral portion” of the base material.
  • the power feeding element 2 is an element that is electrically excited from the outside, and is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 1.
  • the power feeding element 2 has a power feeding portion 2 s at the center in the longitudinal direction of the substrate 1.
  • a signal received by the antenna 100 is extracted from the power feeding unit 2s.
  • the feed element 2 has straight portions 2a, 2b, 2c and 2d.
  • the straight portion 2 a extends from the power supply portion 2 s to the both ends in the longitudinal direction of the base 1 from the upper surface 1 a of the base 1.
  • the straight portion 2b extends along the both ends of the base material 1 in the short direction of the base material 1, and further extends on the side surface 1b of the base material 1 to the bottom surface side.
  • the straight line portion 2 c is provided on the inner side of the end portion in the longitudinal direction of the substrate 1 and substantially parallel to the straight line portion 2 b.
  • the straight portion 2d extends on the side surface 1b of the substrate 1 along the bottom surface in the center direction of the substrate 1.
  • the feed element 2 is arranged so as to surround the cut-out portion 1c.
  • the two front end portions 2t of the power feeding element 2 are arranged in positions near the power feeding portion 2s through the cutout portion 1c in the vicinity of the center of the base 1 in the longitudinal direction.
  • the straight portions 2b and 2c of the feed element 2 are branched between the straight portions 2a and 2d, but the thickness of one straight portion is increased by adjusting the interval between the straight portions 2b and 2c. The same effect as the case can be obtained.
  • the non-excitation element 3 is a linear element, and is provided on the upper surface 1 a of the substrate 1.
  • the non-excitation element 3 is disposed in the vicinity of the straight line portion 2 a of the power feeding element 2 and substantially parallel to the straight line portion 2 a.
  • the non-exciting element 3 has a role of setting the antenna characteristics to the two-resonance state and expanding the band in which transmission and reception can be performed by being arranged close to the feeding element 2.
  • the antenna 100 includes a power feeding element 2 that is electrically excited from the outside and a non-excitation element 3 that is disposed in the vicinity thereof. Two resonance characteristics are provided in the frequency band.
  • the pattern of the feeding element 2 is obtained by bending a plurality of linear elements in accordance with the shape of the substrate 1. Thereby, the length of the feed element in the longitudinal direction can be shortened, and the entire antenna 100 can be reduced in size.
  • the feed element 2 when the feed element 2 is arranged along the outer peripheral shape of the longitudinal base material 1, the feed part 2s and the tip part 2t of the feed element 2 are close to each other. There is a problem that electromagnetic coupling occurs between the two and the characteristics of the antenna deteriorate. Therefore, in the present invention, in order to suppress the electromagnetic coupling between the power feeding portion 2s and the tip portion 2t of the power feeding element 2, the central portion of the longitudinal base material 1 is cut out to provide the cutout portion 1c. . When air is interposed between the power feeding unit 2s and the tip 2t of the power feeding element 2, the electromagnetic coupling between the two can be weakened. As a result, it is possible to suppress the deterioration of the characteristics of the intermediate portion between the two resonance characteristics, and an antenna having stable characteristics can be realized.
  • FIG. 1B is a perspective view of an antenna 110 according to a comparative example.
  • the antenna 110 of the comparative example has the same structure as the antenna 100 except that the cut-out portion 1c is not provided.
  • FIG. 2A shows the impedance characteristics of the antenna 100 of the first embodiment of the present invention
  • FIG. 2B shows the impedance characteristics of the antenna 110 of the comparative example.
  • the horizontal axis represents frequency
  • the vertical axis represents impedance.
  • the graph Re in the figure shows the real number (Real) component of the impedance
  • the graph Im shows the imaginary number (Imaginary) component.
  • the maximum value of the real component Re is smaller and the change of the imaginary component Im is smaller in the antenna 100 of the first embodiment. That is, the antenna 100 of the first embodiment is more stable with less change in impedance characteristics.
  • FIG. 3 (a) shows the VSWR (Voltage Standing Wave Ratio) of the antenna 100 of the first embodiment
  • FIG. 3 (b) shows the VSWR of the antenna 110 of the comparative example. Since the antenna 100 of the first embodiment has a smaller change in impedance characteristics, a change in VSWR within a desired band is smaller. In particular, it can be seen that the characteristic deterioration between the two resonance points is suppressed. As a result, even if the reception frequency band changes, there is no significant difference in the reception power, and there is an advantage that the reception level becomes almost flat.
  • the antenna 100 shown in FIG. 1 (a) has a C-shaped planar shape. However, as in the antenna 100a shown in FIG. It is good also as a shape. Also in this case, an effect of suppressing electromagnetic coupling between the power feeding portion 2s and the tip portion 2t of the power feeding element 2 can be obtained by the cutout portion 1c.
  • the non-exciting element 3 may be provided on the inner side of the feeding element 2, that is, on the cut-out portion 1c side. 4B shows an example of a slot antenna, the non-exciting element 3 may be provided inside the feeding element 2 in the C-shaped antenna 100 shown in FIG.
  • the antenna 100 by enclosing the antenna 100 in the resin case 7, it is possible to prevent the user from directly touching a conductor portion constituting the element. Thereby, corrosion of the element due to rust or the like can be prevented.
  • the antennas 100a and 100b may be similarly enclosed in a resin case.
  • the antenna 100 when the antenna 100 is disposed close to the dielectric material 8 having an area relatively larger than the size of the antenna 100, the antenna 100 is installed alone (the periphery is covered with air). The resonance frequency can be lowered compared to the case of Thereby, the antenna can be further reduced in size. The same applies to the antennas 100a and 100b. At this time, the antenna may or may not be enclosed in the resin case 7.
  • the dielectric material 8 in the case of a vehicle-mounted antenna, for example, a windshield of a vehicle, a dashboard, and the like can be cited.
  • FIG. 6A is a perspective view of an antenna according to the second embodiment.
  • the antenna 200 includes a longitudinal base 11, a feeding element 12, and a non-excitation element 13.
  • the length and width of the power feeding element 12 and the non-excitation element 13 and the size, such as the length, width, and thickness of the base material 11 are determined so that terrestrial digital broadcasting can be satisfactorily received.
  • the substrate 11 has a longitudinal shape and is made of a dielectric material such as ceramic.
  • the dielectric constant of the substrate 1 is about 20
  • the length of the substrate 11 is about 100 to 150 mm
  • the thickness of the substrate 11 is about 3 to 5 mm.
  • the center part of the base material 11 is hollowed out in a rectangular shape, and a cutout part 11c is provided.
  • the base material 11 has a slot-type planar shape.
  • the cutout portion 11c corresponds to the center portion of the base material, and the portion of the base material 11 on the outer periphery of the cutout portion 11c corresponds to the outer peripheral portion of the base material.
  • the power feeding element 12 is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 11.
  • the power feeding element 12 has a power feeding portion 12 s at the center in the longitudinal direction of the base material 11.
  • the power feeding element 12 has a plurality of linear portions 12 a, 12 b, 12 c and 12 d provided on the upper surface 11 a of the substrate 11.
  • the straight line portion 12a extends from the power supply portion 12s to the vicinity of both ends of the cutout portion 11c in the longitudinal direction of the base material 11.
  • the straight portion 12b extends along the outer periphery of the base material 11 to the end in the longitudinal direction.
  • the straight portion 12 c extends in the short direction of the base material 11 at both ends in the longitudinal direction of the base material 11.
  • the straight portion 12d extends from the longitudinal end of the substrate 11 in the central direction.
  • the power feeding element 12 is disposed so as to surround the cut-out portion 11c.
  • the power feeding element 12 is formed only on the upper surface 11a of the base material 11, and is not formed on the side surface of the base material 11. Can be easily formed, and the manufacturing cost can be reduced.
  • the non-excitation element 13 is a linear element, and is provided on the upper surface 11 a of the substrate 11.
  • the non-excitation element 13 is disposed in the vicinity of the straight line portion 12a of the power feeding element 12 and substantially parallel to the straight line portion 12a.
  • a central portion of the longitudinal base 11 is cut out to provide a cutout portion 11c. Yes.
  • the electromagnetic coupling between the two can be weakened.
  • the antenna 210 of the comparative example has the same structure as the antenna 200 except that the cut-out portion 1 c is not provided.
  • the following characteristics are shown in FIGS. 6B and 6C, in which the antennas 200 and 210 are enclosed in the resin case 7, and a dielectric material having a relatively large area as shown in FIG. 8 is obtained when it is arranged close to 8.
  • FIG. 7A shows the impedance characteristics of the antenna 200 of the second embodiment of the present invention
  • FIG. 7B shows the impedance characteristics of the antenna of the comparative example.
  • the horizontal axis represents frequency
  • the vertical axis represents impedance.
  • the graph Re in the figure shows the real component of the impedance
  • the graph Im shows the imaginary component.
  • the antenna 200 of the second embodiment has a smaller maximum value of the real component Re and a smaller change of the imaginary component Im. That is, the antenna 200 of the second embodiment is more stable with less change in impedance characteristics.
  • FIG. 8A shows the VSWR of the antenna 200 of the second embodiment
  • FIG. 8B shows the VSWR of the antenna of the comparative example. Since the antenna 200 of the second embodiment has a smaller change in impedance characteristics, a change in VSWR within a desired band is smaller. In particular, it can be seen that the characteristic deterioration between the two resonance points is suppressed. As a result, even if the reception frequency band changes, there is no significant difference in the reception power, and there is an advantage that the reception level becomes almost flat.
  • the characteristic deterioration of the intermediate portion of the two resonance characteristics can be reduced also by making the widths of the respective linear portions 12a to 12d constituting the feeding element 12 different. Suppressed.
  • the non-excitation element 13 may be provided on the inner side of the feeding element 12, that is, on the cut-out portion 11c side.
  • the antenna 200 is an example of a slot-shaped antenna
  • the base material 11 may have a C-shaped planar shape as in the antenna 100 shown in FIG.
  • the resonance frequency can be increased as compared with the case where the antenna 200 is installed alone. Can be lowered. Thereby, the antenna can be further reduced in size. At this time, the antenna may or may not be enclosed in the resin case 7.
  • FIG. 9A is a perspective view of an antenna according to the third embodiment
  • FIG. 9B is an exploded perspective view thereof.
  • the antenna 300 includes a longitudinal substrate 21, a power feeding element 22, a non-excitation element 23, and a longitudinal base material 24.
  • the external dimensions of the substrate 21 and the base material 24 are substantially the same.
  • the lengths and widths of the power feeding element 22 and the non-excitation element 23 and the sizes such as the lengths, widths, and thicknesses of the substrate 21 and the base material 24 are determined so that digital terrestrial broadcasting can be received satisfactorily.
  • the substrate 21 is a low dielectric constant substrate, and an example thereof includes an FR4 printed circuit board used for pattern wiring of an electronic circuit. As shown in FIG. 9B, the feeding element 22 and the non-excitation element 23 are formed on the substrate 21. The substrate 21 is not formed with a cut-out portion or the like.
  • the feeding element 22 is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 21.
  • the power feeding element 22 has a power feeding portion 22 s at the center in the longitudinal direction of the substrate 21.
  • the power feeding element 22 has a plurality of linear portions 22 a, 22 b and 22 c provided on the upper surface of the substrate 21.
  • the straight portion 22 a extends from the power supply portion 22 s to both ends of the substrate 21 in the longitudinal direction of the substrate 21.
  • the straight portion 22b extends along the outer periphery of the substrate 21 to the end in the short direction.
  • the straight portion 22 c extends from the longitudinal end of the substrate 21 in the central direction.
  • the non-excitation element 23 is a linear element and is provided on the upper surface of the substrate 21.
  • the non-excitation element 23 is disposed in the vicinity of the linear portion 22a of the power feeding element 22 and substantially parallel to the linear portion 22a.
  • the base material 24 has a longitudinal shape and is made of a dielectric material such as alumina.
  • the base material 24 is disposed on the surface of the substrate 21 on which the power feeding element 22 and the non-excitation element 23 are formed, and functions as a dielectric cover.
  • the dielectric constant of the base material 24 is higher than the dielectric constant of the substrate 21.
  • the relative dielectric constant of the substrate 21 using the FR4 printed circuit board is about 4 to 5
  • the relative dielectric constant of the base material 24 is about 8 to 10.
  • the length of the substrate 21 and the base material 24 is about 100 to 150 mm
  • the thickness of the substrate 21 is about 1 mm
  • the thickness of the base material 24 is about 2 mm.
  • the central portion of the base material 24 is cut into a rectangular shape, and a cutout portion 24c is provided.
  • the base material 24 has a slot-type planar shape.
  • the cutout portion 24c corresponds to the center portion of the base material, and the portion of the base material 24 in the outer periphery of the cutout portion 24c corresponds to the outer peripheral portion.
  • the pattern of the feeding element 22 and the non-excitation element 23 is formed on the substrate 21 such as a low-cost high-frequency circuit substrate instead of the dielectric base material 24, and the dielectric is not formed thereon.
  • a body substrate 24 is placed. Since the cost of forming the element on the substrate 21 is lower than that of forming the element on the dielectric substrate itself, the cost for manufacturing the antenna can be reduced.
  • a central portion of the longitudinal base material 24 is cut out to provide a cutout portion 24c. Yes.
  • the electromagnetic coupling between the power feeding portion 22s and the tip portion 22t of the power feeding element 22 can be weakened.
  • the substrate 21 is not provided with a hollow portion in the present embodiment, so that the substrate 21 exists between the power feeding portion 22s and the tip portion 22t of the power feeding element 22. Will do.
  • the dielectric constant of the substrate 21 is sufficiently lower than the dielectric constant of the base member 24 as described above, even when the substrate 21 is present, the electromagnetic coupling between the power feeding portion 22s and the tip portion 22t of the power feeding element 22 is achieved. The effect which suppresses is acquired.
  • the dielectric constant of the printed circuit board of FR4 used as the substrate 21 is about 4.5, and electromagnetic coupling can occur when the received signal frequency is a high frequency of about several GHz.
  • this embodiment assumes reception of terrestrial digital broadcasting, and if the relative permittivity of this base material 21, there is almost no electromagnetic coupling to signals in the band of terrestrial digital broadcasting. Therefore, it is not necessary to form a cutout portion in the substrate 21.
  • the characteristics of the antenna of the third embodiment will be described. The following characteristics were obtained when the antenna 200 of the third embodiment was enclosed in the resin case 7 and further placed close to the dielectric material 8 having a relatively large area as shown in FIG. Is.
  • FIG. 10A shows impedance characteristics of the antenna 300 according to the third embodiment of the present invention.
  • FIG. 10B shows the impedance characteristics of the antenna of the second embodiment of the present invention.
  • the horizontal axis represents frequency, and the vertical axis represents impedance.
  • the graph Re in the figure shows the real component of the impedance, and the graph Im shows the imaginary component.
  • the antenna 300 of the third embodiment also has a small maximum value of the real component Re and a small change in the imaginary component Im.
  • FIG. 11A shows the VSWR of the antenna 300 of the third embodiment.
  • FIG. 10B shows the VSWR of the antenna 200 of the second embodiment. Both show stable two-resonance characteristics within the frequency band of terrestrial digital broadcasting.
  • the width of each of the linear portions 22a to 22c constituting the feeding element 22 is also made different, so that the intermediate portion of the two resonance characteristics can be obtained. Deterioration of characteristics is suppressed.
  • the non-excitation element 23 may be provided on the inner side of the feeding element 22, that is, on the side of the cutout portion 24c.
  • the antenna 200 is an example of a slot-shaped antenna
  • the base member 24 may have a C-shaped planar shape like the antenna 100 shown in FIG.
  • the antenna 300 when the antenna 300 is disposed close to the dielectric material 8 having an area relatively larger than the size of the antenna 300, when the antenna 300 is installed alone (the periphery is covered with air).
  • the resonance frequency can be lowered as compared with the case of Thereby, the antenna can be further reduced in size.
  • the antenna may or may not be enclosed in the resin case 7.
  • the amplifier circuit 27 can be mounted inside the cutout portion 24c of the base material 24. Thereby, the thickness of the antenna 300 including the amplifier circuit 27 can be reduced.
  • a signal received by the elements 22 and 23 of the antenna 300 and output from the power feeding unit 22s is amplified by the amplifier circuit 27 and supplied to an external circuit through the cable 27a.
  • the amplifier circuit 28 may be formed on the substrate 21 as shown in FIG. That is, after the feeding element 22, the non-excitation element 23 and the amplifier circuit 28 are formed on the substrate 21, the dielectric base material 24 is mounted on the substrate 21. Also by this, since the electronic components included in the amplifier circuit 28 are accommodated in the cutout portion 24c of the substrate 24, the thickness of the antenna 300 itself including the amplifier circuit 28 can be reduced.
  • FIGS. 13A to 13C show modifications of the dielectric base material 24.
  • the base material 24 should just cover the place where the wavelength contraction effect is effectively obtained on the pattern of the power feeding element 22 formed on the substrate 21.
  • the place where the wavelength contraction effect is effectively obtained refers to a portion where the electromagnetic field coupling between the patterns is strong, and this portion may be covered. This location is determined by simulation or experiment. For example, the vicinity of the end portion of the power feeding element and the vicinity of the power feeding portion are not necessarily covered. Therefore, the substrate 24 has a C-shape as shown in FIG. 13A, a concave shape as shown in FIG. 13B, and a slot shape shown in FIG. Such a concave character can be divided into two.
  • all of the dielectric bases 1, 11, and 24 have a rectangular planar shape, but the application of the present invention is not limited to this. If the length in one direction is a longitudinal shape that is sufficiently longer than the length in the direction perpendicular thereto, an elliptical shape or a rhombic planar shape may be used.
  • the hollow portions 1c, 11c, and 24c formed in the dielectric base materials 1, 11, and 24 are spaces, and air is present.
  • a dielectric having a dielectric constant sufficiently lower than the dielectric constant of the base materials 1, 11, 24 may be disposed inside the cut-out portions 1 c, 11 c, 24 c.
  • the power feeding elements 2, 12, and 22 are all in contact with the dielectric base materials 1, 11, and 24, but this is not essential, and the dielectric base material is the power feeding element. It is only necessary to cover a portion where the above wavelength contraction effect can be obtained. Therefore, the arrangement may be such that a part of the feed element is not in contact with the dielectric substrate.
  • the feed elements 2, 12, and 22 are all linear, but the application of the present invention is not limited to this.
  • the power feeding element may have a zigzag shape or a meander shape.
  • the shape of the dielectric bases 1, 11, and 24 is a rectangular parallelepiped, but the present invention is not limited to this.
  • the base material may have an elliptical shape or a rhombus shape in plan view.
  • the power feeding element may be disposed along the outer periphery of the shape, or may be disposed in a rectangular shape.
  • the present invention can be used for a receiving antenna for terrestrial digital broadcasting mounted on a vehicle. It can also be used as an antenna for receiving terrestrial digital broadcasts for small portable devices such as portable TVs and portable game machines.

Abstract

An elongated antenna has a base material, a feeding element and a nonexciting element. The base material is elongated and the permittivity is different in the outer peripheral portion and the central portion. The feeding element is in contact with at least the outer peripheral portion and arranged along the profile of the outer peripheral portion. The nonexciting element is arranged in proximity to the feeding element. The feeding element is thereby arranged in the outer peripheral portion of the base material, i.e. on the outside of the central portion thereof. When the feeding element is arranged along the outer peripheral portion of the elongated base material, the feeding portion approaches the distal end of the feeding element and coupling of electromagnetic field takes place between them. But since the central portion of the base material is dug out suitably and the permittivity is low as compared with the outer peripheral portion, such coupling of electromagnetic field can be suppressed.

Description

長手形状アンテナLongitudinal antenna
　本発明は、小型アンテナに関する。 The present invention relates to a small antenna.
　現在、車両での地上波デジタル放送受信用アンテナとしてはフィルムアンテナがよく用いられている。 Currently, film antennas are often used as terrestrial digital broadcast receiving antennas in vehicles.
　しかし、フィルムアンテナは、一度貼り付けてしまうと貼り替えがほとんどできない。従って、ユーザや車用品販売店の作業者は取付作業に過剰な慎重さが要求される。また、作業時間も長くなってしまう。このように、フィルムアンテナは非常に取り扱いにくい。 However, once a film antenna is pasted, it can hardly be replaced. Therefore, the user and the operator of the vehicle supply store are required to be excessively careful in the installation work. In addition, the work time becomes longer. Thus, the film antenna is very difficult to handle.
　また、一度剥がしたフィルムアンテナはほとんど再利用できず、廃棄せざるを得ない。貼り付けに失敗すると即廃棄しなければならないという性質は、環境保護の観点から好ましくない。 Also, once peeled off the film antenna can hardly be reused and must be discarded. The property that it must be discarded immediately if the pasting fails is undesirable from the viewpoint of environmental protection.
　なお、携帯電話などに使用される小型アンテナの例が特許文献１、２に記載されている。 In addition, Patent Documents 1 and 2 describe examples of small antennas used for mobile phones and the like.
特開２００２－２１７６２８号公報JP 2002-217628 A 特開２００５－３０３６３７号公報JP 2005-303637 A
　本発明が解決しようとする課題としては、上記のようなものが例として挙げられる。本発明は、車両に搭載しても目立たない程度に小型であり、地上波デジタル放送の周波数帯域をカバーできる広帯域な非フィルムタイプの小型アンテナを提供することを課題とする。 Examples of problems to be solved by the present invention include the above. It is an object of the present invention to provide a wide-band non-film type small antenna that is small enough to be inconspicuous even when mounted on a vehicle and can cover the frequency band of terrestrial digital broadcasting.
　請求項１に記載の発明による長手形状アンテナは、長手形状であり、外周部と中心部とで誘電率が異なる第１の基材と、前記第１の基材の外周部と少なくとも接しており、かつ、前記外周部の形状に沿うように配置されている給電素子と、前記給電素子と近接配置されている非励振素子と、を備えることを特徴とする。 The longitudinal antenna according to the first aspect of the present invention has a longitudinal shape and is at least in contact with the first base material having a different dielectric constant between the outer peripheral portion and the central portion, and the outer peripheral portion of the first base material. And it is provided with the feed element arrange | positioned so that the shape of the said outer peripheral part may be followed, and the non-excitation element arrange | positioned in proximity to the said feed element.
第１実施例及び比較例のアンテナの斜視図である。It is a perspective view of the antenna of the 1st example and a comparative example. 第１実施例及び比較例のアンテナのインピーダンス特性である。It is the impedance characteristic of the antenna of 1st Example and a comparative example. 第１実施例及び比較例のアンテナのＶＳＷＲ特性である。It is a VSWR characteristic of the antenna of a 1st Example and a comparative example. 第１実施例の変形例によるアンテナの斜視図である。It is a perspective view of the antenna by the modification of 1st Example. 第１実施例の変形例によるアンテナの斜視図である。It is a perspective view of the antenna by the modification of 1st Example. 第２実施例及び比較例のアンテナの斜視図である。It is a perspective view of the antenna of 2nd Example and a comparative example. 第２実施例及び比較例のアンテナのインピーダンス特性である。It is the impedance characteristic of the antenna of 2nd Example and a comparative example. 第２実施例及び比較例のアンテナのＶＳＷＲ特性である。It is a VSWR characteristic of the antenna of 2nd Example and a comparative example. 第３実施例のアンテナの斜視図である。It is a perspective view of the antenna of 3rd Example. 第３実施例及び第２実施例のアンテナのインピーダンス特性である。It is the impedance characteristic of the antenna of 3rd Example and 2nd Example. 第３実施例及び第２実施例のアンテナのＶＳＷＲ特性である。It is the VSWR characteristic of the antenna of 3rd Example and 2nd Example. 第３実施例の変形例のアンテナの斜視図である。It is a perspective view of the antenna of the modification of 3rd Example. 第３実施例における誘電体基材の形状の例である。It is an example of the shape of the dielectric base material in 3rd Example.
符号の説明Explanation of symbols
　１、１１、２４　基材
　２、１２、２２　給電素子
　３、１３、２３　非励振素子
　７　樹脂ケース
　８　誘電体素材
　２１　基板
　２７、２８　アンプ回路
　１００、２００、３００　アンテナ 1, 11, 24 Base material 2, 12, 22 Feeding element 3, 13, 23 Non-excitation element 7 Resin case 8 Dielectric material 21 Substrate 27, 28 Amplifier circuit 100, 200, 300 Antenna
　本発明の好適な実施形態による長手形状アンテナは、長手形状であり、外周部と中心部とで誘電率が異なる第１の基材と、前記第１の基材の外周部と少なくとも接しており、かつ、前記外周部の形状に沿うように配置されている給電素子と、前記給電素子と近接配置されている非励振素子と、を備える。 A longitudinal antenna according to a preferred embodiment of the present invention has a longitudinal shape, and is at least in contact with a first base material having a different permittivity between an outer peripheral portion and a central portion, and an outer peripheral portion of the first base material. And a power feeding element disposed along the shape of the outer peripheral portion, and a non-excitation element disposed close to the power feeding element.
　上記のアンテナでは、第１の基材は例えばセラミックなどの誘電体により構成され、外周部と中心部とで誘電率が異なる。給電素子は、外周部と少なくとも一部で接しており、かつ、外周部の形状に沿って配置されている。そして、給電素子に近接して非励振素子が配置される。給電素子は、基材の外周部、つまり基材の中心部の外側に配置されている。長手形状の基材の外周部に沿って給電素子を配置すると、給電部と給電素子の先端部とが接近し、両者間に電磁界的結合が生じうる。しかし、上記のアンテナでは、給電部と給電素子との間に介在する基材の中心部は外周部と誘電率が異なるので、そのような電磁界的結合を抑制することができる。 In the above antenna, the first base material is made of a dielectric material such as ceramic, and the outer peripheral portion and the central portion have different dielectric constants. The power feeding element is at least partially in contact with the outer peripheral portion, and is disposed along the shape of the outer peripheral portion. And a non-excitation element is arrange | positioned in proximity to a feed element. The power feeding element is disposed on the outer peripheral portion of the base material, that is, outside the central portion of the base material. When the power feeding element is disposed along the outer periphery of the longitudinal base material, the power feeding part and the tip of the power feeding element come close to each other, and electromagnetic coupling may occur between them. However, in the antenna described above, since the dielectric constant of the center portion of the base material interposed between the power feeding portion and the power feeding element is different from that of the outer peripheral portion, such electromagnetic coupling can be suppressed.
　基材の中心部の誘電率は、外周部の誘電率より小さいことが好ましい。好適な例では前記第１の基材は、前記中心部がくりぬかれている。よって、中心部に空気が介在することにより、給電部と給電素子の先端部との電磁界的結合が抑制される。好適な例では、第１の基材は、中心部のみがくり抜かれたスロット型の平面形状を有する。他の好適な例では、第１の基材は、さらに長手方向の中央における前記外周部の一部が切断されたＣ字型の平面形状を有する。 The dielectric constant at the center of the substrate is preferably smaller than the dielectric constant at the outer periphery. In a preferred example, the central portion of the first base material is hollowed out. Therefore, the presence of air in the central portion suppresses electromagnetic coupling between the power feeding portion and the tip portion of the power feeding element. In a preferred example, the first base material has a slot-shaped planar shape in which only the central portion is cut out. In another preferred example, the first base material has a C-shaped planar shape in which a part of the outer peripheral portion at the center in the longitudinal direction is further cut.
　上記の長手形状アンテナの一態様では、前記給電素子は、前記第１の基材の短手方向において前記外周部と接している部分の幅が、前記第１の基材の長手方向において前記外周部と接している部分の幅より大きい。給電素子を構成する複数の部分の幅を異ならせることにより、インピーダンス特性を所望の特性となるように調整することができる。 In one aspect of the longitudinal antenna, the feeding element has a width of a portion in contact with the outer peripheral portion in the short direction of the first base material, and the outer periphery in the longitudinal direction of the first base material. It is larger than the width of the part in contact with the part. By varying the widths of the plurality of portions constituting the power feeding element, the impedance characteristics can be adjusted to have desired characteristics.
　上記の長手形状アンテナの他の一態様では、前記給電素子は、前記第１の基材の短手方向において前記外周部と接している部分が複数に分岐している。給電素子の分岐している部分の間隔を適切に設定することにより、インピーダンス特性を所望の特性となるように調整することができる。 In another aspect of the above long antenna, the feeding element has a plurality of portions in contact with the outer peripheral portion in the short direction of the first base material. By appropriately setting the interval between the branched portions of the feed element, the impedance characteristic can be adjusted to a desired characteristic.
　上記の長手形状アンテナの他の一態様は、前記第１の基材の外周部の誘電率より低い誘電率を有する第２の基材を備え、前記給電素子及び前記非励振素子は、前記第２の基材に形成されている。この態様では、第２の基材上に給電素子及び非励振素子が形成され、その上に誘電体の基材が配置される。給電素子や非励振素子を誘電体の基材に形成すると製造コストが高くなる。給電素子及び非励振素子を第２の基材に形成することにより、製造コストを下げることができる。 Another aspect of the longitudinal antenna includes a second base material having a dielectric constant lower than a dielectric constant of an outer peripheral portion of the first base material, and the feed element and the non-excitation element include the first base 2 base materials. In this aspect, the feeding element and the non-excitation element are formed on the second base material, and the dielectric base material is disposed thereon. If a feed element or a non-excitation element is formed on a dielectric substrate, the manufacturing cost increases. By forming the power feeding element and the non-excitation element on the second base material, the manufacturing cost can be reduced.
　上記の長手形状アンテナの他の一態様では、前記給電素子の給電部と、前記給電素子の２つの端部とは、前記第２の基材の長手方向における中央位置近傍で相互に対向配置されている。この場合、特に給電部と給電素子の２つの端部との間に電磁界的結合が生じやすくなるが、基材の中心部の誘電率が外周部と異なるので、そのような結合が効果的に抑制される。 In another aspect of the longitudinal antenna, the feeding portion of the feeding element and the two end portions of the feeding element are arranged to face each other in the vicinity of the center position in the longitudinal direction of the second base material. ing. In this case, in particular, electromagnetic coupling is likely to occur between the feeding portion and the two end portions of the feeding element, but such a coupling is effective because the dielectric constant of the central portion of the substrate is different from that of the outer peripheral portion. To be suppressed.
　上記の長手形状アンテナの好適な例では、前記給電素子は、前記給電素子の２つの端部付近又は前記給電部付近を除く場所において、前記第１の基材と接している。 In a preferred example of the above longitudinal antenna, the power feeding element is in contact with the first base material in the vicinity of two ends of the power feeding element or in a place excluding the vicinity of the power feeding part.
　好適な例では、上記の長手形状アンテナは、樹脂製のケースに封入される。これにより、給電素子及び非励振素子などの導体部分の腐食を防止することができる。 In a preferred example, the longitudinal antenna is enclosed in a resin case. Thereby, corrosion of conductor parts, such as a feed element and a non-excitation element, can be prevented.
　好適な例では、上記の長手形状アンテナは、前記第１の基材の面積よりも広い面積を有する誘電体に近接配置される。これにより、アンテナの共振周波数を下げることができ、その分アンテナを小型化することが可能となる。 In a preferred example, the above longitudinal antenna is disposed close to a dielectric having an area larger than the area of the first base material. As a result, the resonance frequency of the antenna can be lowered, and the antenna can be downsized accordingly.
　以下、図面を参照して本発明の好適な実施例について説明する。 Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
　［第１実施例］
　図１（ａ）は、第１実施例に係るアンテナの斜視図である。アンテナ１００は、長手形状の基材１と、給電素子２と、非励振素子３とを備える。なお、給電素子２及び非励振素子３の長さや幅、基材１の長さ、幅、厚さなどのサイズは、地上波デジタル放送を良好に受信できるように決定されている。 [First embodiment]
FIG. 1A is a perspective view of an antenna according to the first embodiment. The antenna 100 includes a longitudinal base 1, a feed element 2, and a non-excitation element 3. The length and width of the feed element 2 and the non-excitation element 3 and the length, width, and thickness of the base material 1 are determined so that terrestrial digital broadcasting can be received satisfactorily.
　基材１は、長手形状（板状、スティック状）を有し、セラミックなどの誘電体により構成される。本実施例では、基材１の誘電率は２０程度であり、基材１の長さは１００～１５０ｍｍ程度であり、基材１の厚さは３～５ｍｍ程度である。 The substrate 1 has a longitudinal shape (plate shape, stick shape) and is made of a dielectric material such as ceramic. In this embodiment, the dielectric constant of the substrate 1 is about 20, the length of the substrate 1 is about 100 to 150 mm, and the thickness of the substrate 1 is about 3 to 5 mm.
　基材１の中心部は矩形にくりぬかれ、くり抜き部１ｃが設けられている。また、基材１の長手方向における略中央部は切断され、空間１ｄが形成されている。その結果、基材１はＣ字型の平面形状を有している。本実施例では、くり抜き部１ｃが本発明における基材の「中心部」に相当し、くり抜き部１ｃの外周における基材１の部分が基材の「外周部」に相当する。 The center part of the base material 1 is hollowed out in a rectangular shape, and a cutout part 1c is provided. Moreover, the substantially center part in the longitudinal direction of the base material 1 is cut | disconnected, and the space 1d is formed. As a result, the substrate 1 has a C-shaped planar shape. In this embodiment, the cut-out portion 1c corresponds to the “center portion” of the base material in the present invention, and the portion of the base material 1 on the outer periphery of the cut-out portion 1c corresponds to the “outer peripheral portion” of the base material.
　給電素子２は、外部から電気的に励振される素子であり、直線状の素子を基材１の外周部に沿って複数回折り曲げて配置することにより形成されている。給電素子２は、基材１の長手方向における中央に給電部２ｓを有する。アンテナ１００により受信された信号は給電部２ｓから取り出される。給電素子２は、直線部分２ａ、２ｂ、２ｃ及び２ｄを有する。直線部分２ａは、基材１の上面１ａを、給電部２ｓから基材の１の長手方向に両端まで延びている。直線部分２ｂは、基材１の両端に沿って、基材１の短手方向に延び、さらに基材１の側面１ｂ上を底面側まで延びている。直線部分２ｃは、基材１の長手方向の端部より内側で、直線部分２ｂと略平行に設けられている。直線部分２ｄは、基材１の側面１ｂ上を底面に沿って基材の１の中央方向へ延びている。こうして、給電素子２は、くり抜き部１ｃを取り囲むように配置されている。給電素子２の２つの先端部２ｔは、基材の１の長手方向の中央付近において、くり抜き部１ｃを介して、給電部２ｓとほぼ対向する位置に配置されている。 The power feeding element 2 is an element that is electrically excited from the outside, and is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 1. The power feeding element 2 has a power feeding portion 2 s at the center in the longitudinal direction of the substrate 1. A signal received by the antenna 100 is extracted from the power feeding unit 2s. The feed element 2 has straight portions 2a, 2b, 2c and 2d. The straight portion 2 a extends from the power supply portion 2 s to the both ends in the longitudinal direction of the base 1 from the upper surface 1 a of the base 1. The straight portion 2b extends along the both ends of the base material 1 in the short direction of the base material 1, and further extends on the side surface 1b of the base material 1 to the bottom surface side. The straight line portion 2 c is provided on the inner side of the end portion in the longitudinal direction of the substrate 1 and substantially parallel to the straight line portion 2 b. The straight portion 2d extends on the side surface 1b of the substrate 1 along the bottom surface in the center direction of the substrate 1. Thus, the feed element 2 is arranged so as to surround the cut-out portion 1c. The two front end portions 2t of the power feeding element 2 are arranged in positions near the power feeding portion 2s through the cutout portion 1c in the vicinity of the center of the base 1 in the longitudinal direction.
　なお、給電素子２の直線部分２ｂと２ｃは直線部分２ａと２ｄの間で分岐しているが、直線部分２ｂと２ｃの間隔を調整することにより、１本の直線部分の太さを太くした場合と同様の効果を得ることができる。 The straight portions 2b and 2c of the feed element 2 are branched between the straight portions 2a and 2d, but the thickness of one straight portion is increased by adjusting the interval between the straight portions 2b and 2c. The same effect as the case can be obtained.
　非励振素子３は、直線状の素子であり、基材１の上面１ａに設けられている。非励振素子３は、給電素子２の直線部分２ａの近傍に、直線部分２ａとほぼ平行に配置されている。非励振素子３は、給電素子２に近接配置されることにより、アンテナ特性を２共振の状態とし、送受信可能な帯域を広げる役割を有する。 The non-excitation element 3 is a linear element, and is provided on the upper surface 1 a of the substrate 1. The non-excitation element 3 is disposed in the vicinity of the straight line portion 2 a of the power feeding element 2 and substantially parallel to the straight line portion 2 a. The non-exciting element 3 has a role of setting the antenna characteristics to the two-resonance state and expanding the band in which transmission and reception can be performed by being arranged close to the feeding element 2.
　本実施例のアンテナ１００は、外部から電気的に励振される給電素子２と、その近傍に配置される非励振素子３により構成されており、それらの全長を適宜調整することにより、所望の動作周波数帯域内で２つの共振特性を持たせている。給電素子２のパターンは、基材１の形状に合わせて、直線状の素子を複数回折り曲げたものとなっている。これにより、給電素子の長手方向の長さを短くすることができ、アンテナ１００全体を小型化することができる。 The antenna 100 according to the present embodiment includes a power feeding element 2 that is electrically excited from the outside and a non-excitation element 3 that is disposed in the vicinity thereof. Two resonance characteristics are provided in the frequency band. The pattern of the feeding element 2 is obtained by bending a plurality of linear elements in accordance with the shape of the substrate 1. Thereby, the length of the feed element in the longitudinal direction can be shortened, and the entire antenna 100 can be reduced in size.
　本実施例のように、長手形状の基材１に対して、給電素子２をその外周形状に沿うように配置した場合、給電部２ｓと給電素子２の先端部２ｔとが近接してしまうため、両者間に電磁界的な結合が起こり、アンテナの特性が悪化してしまうという問題がある。そこで、本発明では、給電部２ｓと給電素子２の先端部２ｔとの間の電磁界的な結合を抑制するため、長手形状の基材１の中央部をくり抜いてくり抜き部１ｃを設けている。給電部２ｓと給電素子２の先端部２ｔとの間に空気が介在することにより、両者間の電磁界的な結合を弱めることができる。その結果、２つの共振特性の中間部の特性悪化を抑制することが可能となり、特性の安定したアンテナを実現可能となる。 As in the present embodiment, when the feed element 2 is arranged along the outer peripheral shape of the longitudinal base material 1, the feed part 2s and the tip part 2t of the feed element 2 are close to each other. There is a problem that electromagnetic coupling occurs between the two and the characteristics of the antenna deteriorate. Therefore, in the present invention, in order to suppress the electromagnetic coupling between the power feeding portion 2s and the tip portion 2t of the power feeding element 2, the central portion of the longitudinal base material 1 is cut out to provide the cutout portion 1c. . When air is interposed between the power feeding unit 2s and the tip 2t of the power feeding element 2, the electromagnetic coupling between the two can be weakened. As a result, it is possible to suppress the deterioration of the characteristics of the intermediate portion between the two resonance characteristics, and an antenna having stable characteristics can be realized.
　以下、この点について、比較例と比較しつつ考察する。図１（ｂ）は比較例に係るアンテナ１１０の斜視図である。比較例のアンテナ１１０は、くり抜き部１ｃを設けない点以外は、アンテナ１００と同一構造である。 Hereafter, this point will be considered in comparison with the comparative example. FIG. 1B is a perspective view of an antenna 110 according to a comparative example. The antenna 110 of the comparative example has the same structure as the antenna 100 except that the cut-out portion 1c is not provided.
　図２（ａ）は本発明の第１実施例のアンテナ１００のインピーダンス特性を示し、図２（ｂ）は比較例のアンテナ１１０のインピーダンス特性を示す。横軸は周波数を示し、縦軸はインピーダンスを示す。図中のグラフＲｅはインピーダンスの実数（Ｒｅａｌ）成分を示し、グラフＩｍは虚数（Ｉｍａｇｉｎａｒｙ）成分を示す。図２（ａ）と図２（ｂ）を比較するとわかるように、第１実施例のアンテナ１００の方が、実数成分Ｒｅの極大値が小さく、虚数成分Ｉｍの変化も小さい。つまり、第１実施例のアンテナ１００の方が、インピーダンス特性の変化が少なく、安定している。 2A shows the impedance characteristics of the antenna 100 of the first embodiment of the present invention, and FIG. 2B shows the impedance characteristics of the antenna 110 of the comparative example. The horizontal axis represents frequency, and the vertical axis represents impedance. The graph Re in the figure shows the real number (Real) component of the impedance, and the graph Im shows the imaginary number (Imaginary) component. As can be seen by comparing FIG. 2A and FIG. 2B, the maximum value of the real component Re is smaller and the change of the imaginary component Im is smaller in the antenna 100 of the first embodiment. That is, the antenna 100 of the first embodiment is more stable with less change in impedance characteristics.
　図３（ａ）は第１実施例のアンテナ１００のＶＳＷＲ（Ｖｏｌｔａｇｅ　Ｓｔａｎｄｉｎｇ　Ｗａｖｅ　Ｒａｔｉｏ：電圧定在波比）を示し、図３（ｂ）は比較例のアンテナ１１０のＶＳＷＲを示す。第１実施例のアンテナ１００の方がインピーダンス特性の変化が小さいため、所望の帯域内でのＶＳＷＲの変化が小さくなる。とりわけ、２つの共振点の間の特性悪化が抑制されていることがわかる。これにより、受信周波数帯が変化しても受信電力に大きな差が生じなくなり、受信レベルがフラットに近くなるという利点が得られる。 FIG. 3 (a) shows the VSWR (Voltage Standing Wave Ratio) of the antenna 100 of the first embodiment, and FIG. 3 (b) shows the VSWR of the antenna 110 of the comparative example. Since the antenna 100 of the first embodiment has a smaller change in impedance characteristics, a change in VSWR within a desired band is smaller. In particular, it can be seen that the characteristic deterioration between the two resonance points is suppressed. As a result, even if the reception frequency band changes, there is no significant difference in the reception power, and there is an advantage that the reception level becomes almost flat.
　図１（ａ）に示すアンテナ１００はＣ字型の平面形状を有するが、図４（ａ）に示すアンテナ１００ａのように基材１に対してくり抜き部１ｃのみを設けて、スロット状の平面形状としてもよい。この場合も、くり抜き部１ｃにより給電部２ｓと給電素子２の先端部２ｔとの間の電磁界的結合を抑制する効果が得られる。 The antenna 100 shown in FIG. 1 (a) has a C-shaped planar shape. However, as in the antenna 100a shown in FIG. It is good also as a shape. Also in this case, an effect of suppressing electromagnetic coupling between the power feeding portion 2s and the tip portion 2t of the power feeding element 2 can be obtained by the cutout portion 1c.
　図４（ｂ）に示すアンテナ１００ｂのように、非励振素子３を給電素子２より内側、即ちくり抜き部１ｃ側に設けてもよい。なお、図４（ｂ）はスロット状のアンテナの例であるが、図１に示すＣ字型のアンテナ１００において、非励振素子３を給電素子２より内側に設けることとしてもよい。 As in the antenna 100b shown in FIG. 4B, the non-exciting element 3 may be provided on the inner side of the feeding element 2, that is, on the cut-out portion 1c side. 4B shows an example of a slot antenna, the non-exciting element 3 may be provided inside the feeding element 2 in the C-shaped antenna 100 shown in FIG.
　図４（ｃ）に示すように、アンテナ１００を樹脂ケース７に封入することにより、ユーザが素子を構成する導体部分に直接触れることを防止できる。これにより、錆などによる素子の腐食を防止できる。なお、アンテナ１００ａ、１００ｂを同様に樹脂ケースに封入してもよい。 As shown in FIG. 4C, by enclosing the antenna 100 in the resin case 7, it is possible to prevent the user from directly touching a conductor portion constituting the element. Thereby, corrosion of the element due to rust or the like can be prevented. The antennas 100a and 100b may be similarly enclosed in a resin case.
　また、図５に示すように、アンテナ１００を、その大きさよりも相対的に広い面積を有する誘電体素材８に近接させて配置させれば、単独で設置した場合（周囲が空気で覆われている場合）と比較して共振周波数を下げることができる。これにより、さらにアンテナを小型化することができる。アンテナ１００ａ、１００ｂなどについても同様である。このとき、アンテナは樹脂ケース７に封入されていても、されていなくてもよい。なお、誘電体素材８としては、車載用アンテナの場合、例えば車両のフロントガラス、ダッシュボードなどが挙げられる。 In addition, as shown in FIG. 5, when the antenna 100 is disposed close to the dielectric material 8 having an area relatively larger than the size of the antenna 100, the antenna 100 is installed alone (the periphery is covered with air). The resonance frequency can be lowered compared to the case of Thereby, the antenna can be further reduced in size. The same applies to the antennas 100a and 100b. At this time, the antenna may or may not be enclosed in the resin case 7. In addition, as the dielectric material 8, in the case of a vehicle-mounted antenna, for example, a windshield of a vehicle, a dashboard, and the like can be cited.
　［第２実施例］
　図６（ａ）は、第２実施例に係るアンテナの斜視図である。アンテナ２００は、長手形状の基材１１と、給電素子１２と、非励振素子１３とを備える。なお、給電素子１２及び非励振素子１３の長さや幅、基材１１の長さ、幅、厚さなどのサイズは、地上波デジタル放送を良好に受信できるように決定されている。 [Second Embodiment]
FIG. 6A is a perspective view of an antenna according to the second embodiment. The antenna 200 includes a longitudinal base 11, a feeding element 12, and a non-excitation element 13. The length and width of the power feeding element 12 and the non-excitation element 13 and the size, such as the length, width, and thickness of the base material 11 are determined so that terrestrial digital broadcasting can be satisfactorily received.
　基材１１は、長手形状を有し、セラミックなどの誘電体により構成される。本実施例では、基材１の誘電率は２０程度であり、基材１１の長さは１００～１５０ｍｍ程度であり、基材１１の厚さは３～５ｍｍ程度である。 The substrate 11 has a longitudinal shape and is made of a dielectric material such as ceramic. In this embodiment, the dielectric constant of the substrate 1 is about 20, the length of the substrate 11 is about 100 to 150 mm, and the thickness of the substrate 11 is about 3 to 5 mm.
　基材１１の中心部は矩形にくりぬかれ、くり抜き部１１ｃが設けられている。その結果、基材１１はスロット型の平面形状を有している。本実施例では、くり抜き部１１ｃが基材の中心部に相当し、くり抜き部１１ｃの外周における基材１１の部分が基材の外周部に相当する。 The center part of the base material 11 is hollowed out in a rectangular shape, and a cutout part 11c is provided. As a result, the base material 11 has a slot-type planar shape. In this embodiment, the cutout portion 11c corresponds to the center portion of the base material, and the portion of the base material 11 on the outer periphery of the cutout portion 11c corresponds to the outer peripheral portion of the base material.
　給電素子１２は、直線状の素子を基材１１の外周部に沿って複数回折り曲げて配置することにより形成されている。給電素子１２は、基材１１の長手方向における中央に給電部１２ｓを有する。給電素子１２は、基材１１の上面１１ａに設けられた複数の直線部分１２ａ、１２ｂ、１２ｃ及び１２ｄを有する。直線部分１２ａは、給電部１２ｓから基材１１の長手方向にくり抜き部１１ｃの両端付近まで延びている。直線部分１２ｂは、基材１１の外周に沿って長手方向の端部まで延びている。直線部分１２ｃは基材１１の長手方向の両端において、基材１１の短手方向に延びている。直線部分１２ｄは、基材１１の長手方向の端部から中央方向へ延びている。このように、給電素子１２は、くり抜き部１１ｃを取り囲むように配置されている。なお、第２実施例では、第１実施例と比較して、給電素子１２が基材１１の上面１１ａのみに形成されており、基材１１の側面には形成されていないので、給電素子１２の形成が容易となり、製造コストの低減が可能となる。 The power feeding element 12 is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 11. The power feeding element 12 has a power feeding portion 12 s at the center in the longitudinal direction of the base material 11. The power feeding element 12 has a plurality of linear portions 12 a, 12 b, 12 c and 12 d provided on the upper surface 11 a of the substrate 11. The straight line portion 12a extends from the power supply portion 12s to the vicinity of both ends of the cutout portion 11c in the longitudinal direction of the base material 11. The straight portion 12b extends along the outer periphery of the base material 11 to the end in the longitudinal direction. The straight portion 12 c extends in the short direction of the base material 11 at both ends in the longitudinal direction of the base material 11. The straight portion 12d extends from the longitudinal end of the substrate 11 in the central direction. Thus, the power feeding element 12 is disposed so as to surround the cut-out portion 11c. In the second embodiment, as compared with the first embodiment, the power feeding element 12 is formed only on the upper surface 11a of the base material 11, and is not formed on the side surface of the base material 11. Can be easily formed, and the manufacturing cost can be reduced.
　非励振素子１３は、直線状の素子であり、基材１１の上面１１ａに設けられている。非励振素子１３は、給電素子１２の直線部分１２ａの近傍に、直線部分１２ａとほぼ平行に配置されている。 The non-excitation element 13 is a linear element, and is provided on the upper surface 11 a of the substrate 11. The non-excitation element 13 is disposed in the vicinity of the straight line portion 12a of the power feeding element 12 and substantially parallel to the straight line portion 12a.
　第２実施例においても、給電部１２ｓと給電素子１２の先端部１２ｔとの間の電磁界的な結合を抑制するため、長手形状の基材１１の中央部をくり抜いてくり抜き部１１ｃを設けている。給電部１２ｓと給電素子１２の先端部１２ｔとの間に空気が介在することにより、両者間の電磁界的な結合を弱めることができる。その結果、２つの共振特性の中間部の特性悪化を抑制することが可能となり、特性の安定したアンテナを実現可能となる。 Also in the second embodiment, in order to suppress electromagnetic coupling between the power feeding portion 12s and the tip end portion 12t of the power feeding element 12, a central portion of the longitudinal base 11 is cut out to provide a cutout portion 11c. Yes. When air is interposed between the power feeding part 12s and the tip part 12t of the power feeding element 12, the electromagnetic coupling between the two can be weakened. As a result, it is possible to suppress the deterioration of the characteristics of the intermediate portion between the two resonance characteristics, and an antenna having stable characteristics can be realized.
　以下、この点について、比較例と比較しつつ考察する。比較例のアンテナ２１０は、図６（ｃ）に示すように、くり抜き部１ｃを設けない点以外は、アンテナ２００と同一構造とする。なお、以下の特性は、図６（ｂ）及び６（ｃ）に示すように、アンテナ２００及び２１０を樹脂ケース７に封入し、さらに図５のように相対的に広い面積を有する誘電体素材８に近接させて配置した場合に得られたものである。 Hereafter, this point will be considered in comparison with the comparative example. As shown in FIG. 6C, the antenna 210 of the comparative example has the same structure as the antenna 200 except that the cut-out portion 1 c is not provided. The following characteristics are shown in FIGS. 6B and 6C, in which the antennas 200 and 210 are enclosed in the resin case 7, and a dielectric material having a relatively large area as shown in FIG. 8 is obtained when it is arranged close to 8.
　図７（ａ）は本発明の第２実施例のアンテナ２００のインピーダンス特性を示し、図７（ｂ）は比較例のアンテナのインピーダンス特性を示す。横軸は周波数を示し、縦軸はインピーダンスを示す。図中のグラフＲｅはインピーダンスの実数成分を示し、グラフＩｍは虚数成分を示す。図７（ａ）と図７（ｂ）を比較するとわかるように、第２実施例のアンテナ２００の方が、実数成分Ｒｅの極大値が小さく、虚数成分Ｉｍの変化も小さい。つまり、第２実施例のアンテナ２００の方が、インピーダンス特性の変化が少なく、安定している。 7A shows the impedance characteristics of the antenna 200 of the second embodiment of the present invention, and FIG. 7B shows the impedance characteristics of the antenna of the comparative example. The horizontal axis represents frequency, and the vertical axis represents impedance. The graph Re in the figure shows the real component of the impedance, and the graph Im shows the imaginary component. As can be seen by comparing FIG. 7A and FIG. 7B, the antenna 200 of the second embodiment has a smaller maximum value of the real component Re and a smaller change of the imaginary component Im. That is, the antenna 200 of the second embodiment is more stable with less change in impedance characteristics.
　図８（ａ）は第２実施例のアンテナ２００のＶＳＷＲを示し、図８（ｂ）は比較例のアンテナのＶＳＷＲを示す。第２実施例のアンテナ２００の方がインピーダンス特性の変化が小さいため、所望の帯域内でのＶＳＷＲの変化が小さくなる。とりわけ、２つの共振点の間の特性悪化が抑制されていることがわかる。これにより、受信周波数帯が変化しても受信電力に大きな差が生じなくなり、受信レベルがフラットに近くなるという利点が得られる。 FIG. 8A shows the VSWR of the antenna 200 of the second embodiment, and FIG. 8B shows the VSWR of the antenna of the comparative example. Since the antenna 200 of the second embodiment has a smaller change in impedance characteristics, a change in VSWR within a desired band is smaller. In particular, it can be seen that the characteristic deterioration between the two resonance points is suppressed. As a result, even if the reception frequency band changes, there is no significant difference in the reception power, and there is an advantage that the reception level becomes almost flat.
　また、第２実施例では、図６（ａ）に示すように、給電素子１２を構成する各直線部分１２ａ～１２ｄの幅を異ならせることによっても、２つの共振特性の中間部の特性悪化を抑制している。 Further, in the second embodiment, as shown in FIG. 6A, the characteristic deterioration of the intermediate portion of the two resonance characteristics can be reduced also by making the widths of the respective linear portions 12a to 12d constituting the feeding element 12 different. Suppressed.
　第２実施例においても、図４（ｂ）に示すアンテナ１００ｂと同様に、非励振素子１３を給電素子１２より内側、即ちくり抜き部１１ｃ側に設けてもよい。また、アンテナ２００はスロット状のアンテナの例であるが、図１に示すアンテナ１００のように、基材１１をＣ字型の平面形状としてもよい。 Also in the second embodiment, similarly to the antenna 100b shown in FIG. 4B, the non-excitation element 13 may be provided on the inner side of the feeding element 12, that is, on the cut-out portion 11c side. Further, although the antenna 200 is an example of a slot-shaped antenna, the base material 11 may have a C-shaped planar shape as in the antenna 100 shown in FIG.
　図６（ｂ）に示すように、アンテナ２００を樹脂ケース７に封入することにより、ユーザが素子を構成する導体部分に直接触れることを防止できる。これにより、錆などによる素子の腐食を防止できる。 As shown in FIG. 6B, by enclosing the antenna 200 in the resin case 7, it is possible to prevent the user from directly touching the conductor portion constituting the element. Thereby, corrosion of the element due to rust or the like can be prevented.
　また、図５の例と同様に、アンテナ２００を、その大きさよりも相対的に広い面積を有する誘電体素材８に近接させて配置させれば、単独で設置した場合と比較して共振周波数を下げることができる。これにより、さらにアンテナを小型化することができる。このとき、アンテナは樹脂ケース７に封入されていても、されていなくてもよい。 Similarly to the example of FIG. 5, if the antenna 200 is disposed close to the dielectric material 8 having an area relatively larger than the size, the resonance frequency can be increased as compared with the case where the antenna 200 is installed alone. Can be lowered. Thereby, the antenna can be further reduced in size. At this time, the antenna may or may not be enclosed in the resin case 7.
　［第３実施例］
　図９（ａ）は第３実施例に係るアンテナの斜視図であり、図９（ｂ）はその分解斜視図である。アンテナ３００は、長手形状の基板２１と、給電素子２２と、非励振素子２３と、長手形状の基材２４とを備える。基板２１と基材２４の外形寸法はほぼ同一である。なお、給電素子２２及び非励振素子２３の長さや幅、基板２１及び基材２４の長さ、幅、厚さなどのサイズは、地上波デジタル放送を良好に受信できるように決定されている。 [Third embodiment]
FIG. 9A is a perspective view of an antenna according to the third embodiment, and FIG. 9B is an exploded perspective view thereof. The antenna 300 includes a longitudinal substrate 21, a power feeding element 22, a non-excitation element 23, and a longitudinal base material 24. The external dimensions of the substrate 21 and the base material 24 are substantially the same. The lengths and widths of the power feeding element 22 and the non-excitation element 23 and the sizes such as the lengths, widths, and thicknesses of the substrate 21 and the base material 24 are determined so that digital terrestrial broadcasting can be received satisfactorily.
　基板２１は低誘電率の基板であり、一例としては電子回路のパターン配線で使用されるＦＲ４プリント基板などが挙げられる。図９（ｂ）に示されるように、給電素子２２及び非励振素子２３は基板２１上に形成される。なお、基板２１にはくり抜き部などは形成されない。 The substrate 21 is a low dielectric constant substrate, and an example thereof includes an FR4 printed circuit board used for pattern wiring of an electronic circuit. As shown in FIG. 9B, the feeding element 22 and the non-excitation element 23 are formed on the substrate 21. The substrate 21 is not formed with a cut-out portion or the like.
　給電素子２２は、直線状の素子を基板２１の外周部に沿って複数回折り曲げて配置することにより形成されている。給電素子２２は、基板２１の長手方向における中央に給電部２２ｓを有する。給電素子２２は、基板２１の上面に設けられた複数の直線部分２２ａ、２２ｂ及び２２ｃを有する。直線部分２２ａは、給電部２２ｓから基板２１の長手方向に基板２１の両端まで延びている。直線部分２２ｂは、基板２１の外周に沿って短手方向の端部まで延びている。直線部分２２ｃは、基板２１の長手方向の端部から中央方向へ延びている。 The feeding element 22 is formed by arranging a linear element by bending a plurality of elements along the outer periphery of the substrate 21. The power feeding element 22 has a power feeding portion 22 s at the center in the longitudinal direction of the substrate 21. The power feeding element 22 has a plurality of linear portions 22 a, 22 b and 22 c provided on the upper surface of the substrate 21. The straight portion 22 a extends from the power supply portion 22 s to both ends of the substrate 21 in the longitudinal direction of the substrate 21. The straight portion 22b extends along the outer periphery of the substrate 21 to the end in the short direction. The straight portion 22 c extends from the longitudinal end of the substrate 21 in the central direction.
　非励振素子２３は、直線状の素子であり、基板２１の上面に設けられている。非励振素子２３は、給電素子２２の直線部分２２ａの近傍に、直線部分２２ａとほぼ平行に配置されている。 The non-excitation element 23 is a linear element and is provided on the upper surface of the substrate 21. The non-excitation element 23 is disposed in the vicinity of the linear portion 22a of the power feeding element 22 and substantially parallel to the linear portion 22a.
　基材２４は、長手形状を有し、アルミナなどの誘電体により構成される。基材２４は、給電素子２２及び非励振素子２３が形成された基板２１の面上に配置され、誘電体カバーとして機能する。基材２４の誘電率は基板２１の誘電率より高い。例えば、ＦＲ４プリント基板を用いた基板２１の比誘電率が４～５程度であるのに対して、基材２４の比誘電率は８～１０程度である。また、本実施例では、基板２１及び基材２４の長さは１００～１５０ｍｍ程度、基板２１の厚さは１ｍｍ程度、基材２４の厚さは２ｍｍ程度である。 The base material 24 has a longitudinal shape and is made of a dielectric material such as alumina. The base material 24 is disposed on the surface of the substrate 21 on which the power feeding element 22 and the non-excitation element 23 are formed, and functions as a dielectric cover. The dielectric constant of the base material 24 is higher than the dielectric constant of the substrate 21. For example, the relative dielectric constant of the substrate 21 using the FR4 printed circuit board is about 4 to 5, while the relative dielectric constant of the base material 24 is about 8 to 10. In this embodiment, the length of the substrate 21 and the base material 24 is about 100 to 150 mm, the thickness of the substrate 21 is about 1 mm, and the thickness of the base material 24 is about 2 mm.
　基材２４の中心部は矩形にくりぬかれ、くり抜き部２４ｃが設けられている。その結果、基材２４はスロット型の平面形状を有している。本実施例では、くり抜き部２４ｃが基材の中心部に相当し、くり抜き部２４ｃの外周における基材２４の部分が外周部に相当する。 The central portion of the base material 24 is cut into a rectangular shape, and a cutout portion 24c is provided. As a result, the base material 24 has a slot-type planar shape. In this embodiment, the cutout portion 24c corresponds to the center portion of the base material, and the portion of the base material 24 in the outer periphery of the cutout portion 24c corresponds to the outer peripheral portion.
　本実施例では、誘電体の基材２４ではなく、低コストの高周波回路用基板などの基板２１に給電素子２２及び非励振素子２３のパターンを形成し、その上に素子を形成していない誘電体の基材２４を配置する。誘電体基材そのものに素子を形成するより、基板２１に素子を形成する方がコストが低いので、アンテナを製造するコストを低減することができる。 In the present embodiment, the pattern of the feeding element 22 and the non-excitation element 23 is formed on the substrate 21 such as a low-cost high-frequency circuit substrate instead of the dielectric base material 24, and the dielectric is not formed thereon. A body substrate 24 is placed. Since the cost of forming the element on the substrate 21 is lower than that of forming the element on the dielectric substrate itself, the cost for manufacturing the antenna can be reduced.
　第３実施例においても、給電部２２ｓと給電素子２２の先端部２２ｔとの間の電磁界的な結合を抑制するため、長手形状の基材２４の中央部をくり抜いてくり抜き部２４ｃを設けている。これにより、給電部２２ｓと給電素子２２の先端部２２ｔとの間の電磁界的な結合を弱めることができる。その結果、２つの共振特性の中間部の特性悪化を抑制することが可能となり、特性の安定したアンテナを実現可能となる。なお、第１及び第２実施例と比較すると、本実施例では基板２１にはくり抜き部が設けられていないので、給電部２２ｓと給電素子２２の先端部２２ｔとの間には基板２１が存在することになる。しかし、前述のように基板２１の誘電率は基材２４の誘電率より十分に低いので、基板２１が存在していても、給電部２２ｓと給電素子２２の先端部２２ｔとの電磁界的結合を抑制する効果は得られる。 Also in the third embodiment, in order to suppress electromagnetic coupling between the power feeding portion 22s and the tip end portion 22t of the power feeding element 22, a central portion of the longitudinal base material 24 is cut out to provide a cutout portion 24c. Yes. Thereby, the electromagnetic coupling between the power feeding portion 22s and the tip portion 22t of the power feeding element 22 can be weakened. As a result, it is possible to suppress the deterioration of the characteristics of the intermediate portion between the two resonance characteristics, and an antenna having stable characteristics can be realized. Compared with the first and second embodiments, the substrate 21 is not provided with a hollow portion in the present embodiment, so that the substrate 21 exists between the power feeding portion 22s and the tip portion 22t of the power feeding element 22. Will do. However, since the dielectric constant of the substrate 21 is sufficiently lower than the dielectric constant of the base member 24 as described above, even when the substrate 21 is present, the electromagnetic coupling between the power feeding portion 22s and the tip portion 22t of the power feeding element 22 is achieved. The effect which suppresses is acquired.
　なお、基板２１として使用するＦＲ４のプリント基板の比誘電率は４．５程度であり、受信信号周波数が数ＧＨｚ程度の高周波である場合には電磁界的な結合が生じうる。しかし、本実施例は地上波デジタル放送の受信を想定しており、この基材２１の比誘電率ならば、地上波デジタル放送の帯域の信号に対しては電磁界的な結合がほとんど起こらないので、基板２１にくり抜き部を形成する必要はない。 Note that the dielectric constant of the printed circuit board of FR4 used as the substrate 21 is about 4.5, and electromagnetic coupling can occur when the received signal frequency is a high frequency of about several GHz. However, this embodiment assumes reception of terrestrial digital broadcasting, and if the relative permittivity of this base material 21, there is almost no electromagnetic coupling to signals in the band of terrestrial digital broadcasting. Therefore, it is not necessary to form a cutout portion in the substrate 21.
　以下、第３実施例のアンテナの特性について説明する。なお、以下の特性は、第３実施例のアンテナ２００を樹脂ケース７に封入し、さらに図５のように相対的に広い面積を有する誘電体素材８に近接させて配置した場合に得られたものである。 Hereinafter, the characteristics of the antenna of the third embodiment will be described. The following characteristics were obtained when the antenna 200 of the third embodiment was enclosed in the resin case 7 and further placed close to the dielectric material 8 having a relatively large area as shown in FIG. Is.
　図１０（ａ）は本発明の第３実施例のアンテナ３００のインピーダンス特性を示す。参考として、図１０（ｂ）に本発明の第２実施例のアンテナのインピーダンス特性を示す。横軸は周波数を示し、縦軸はインピーダンスを示す。図中のグラフＲｅはインピーダンスの実数成分を示し、グラフＩｍは虚数成分を示す。図１０（ａ）と図１０（ｂ）が示すように、第３実施例のアンテナ３００も実数成分Ｒｅの極大値が小さく、虚数成分Ｉｍの変化も小さい。 FIG. 10A shows impedance characteristics of the antenna 300 according to the third embodiment of the present invention. For reference, FIG. 10B shows the impedance characteristics of the antenna of the second embodiment of the present invention. The horizontal axis represents frequency, and the vertical axis represents impedance. The graph Re in the figure shows the real component of the impedance, and the graph Im shows the imaginary component. As shown in FIGS. 10A and 10B, the antenna 300 of the third embodiment also has a small maximum value of the real component Re and a small change in the imaginary component Im.
　図１１（ａ）は第３実施例のアンテナ３００のＶＳＷＲを示す。参考として、図１０（ｂ）に第２実施例のアンテナ２００のＶＳＷＲを示す。いずれも地上波デジタル放送の周波数帯域内で安定した２共振の特性を示している。 FIG. 11A shows the VSWR of the antenna 300 of the third embodiment. For reference, FIG. 10B shows the VSWR of the antenna 200 of the second embodiment. Both show stable two-resonance characteristics within the frequency band of terrestrial digital broadcasting.
　第３実施例では、図９（ａ）及び９（ｂ）に示すように、給電素子２２を構成する各直線部分２２ａ～２２ｃの幅を異ならせることによっても、２つの共振特性の中間部の特性悪化を抑制している。 In the third embodiment, as shown in FIGS. 9 (a) and 9 (b), the width of each of the linear portions 22a to 22c constituting the feeding element 22 is also made different, so that the intermediate portion of the two resonance characteristics can be obtained. Deterioration of characteristics is suppressed.
　第３実施例においても、図４（ｂ）に示すアンテナ１００ｂと同様に、非励振素子２３を給電素子２２より内側、即ちくり抜き部２４ｃ側に設けてもよい。また、アンテナ２００はスロット状のアンテナの例であるが、図１に示すアンテナ１００のように、基材２４をＣ字型の平面形状としてもよい。 Also in the third embodiment, similarly to the antenna 100b shown in FIG. 4B, the non-excitation element 23 may be provided on the inner side of the feeding element 22, that is, on the side of the cutout portion 24c. Further, although the antenna 200 is an example of a slot-shaped antenna, the base member 24 may have a C-shaped planar shape like the antenna 100 shown in FIG.
　図６（ｂ）に示すように、アンテナ３００を樹脂ケース７に封入することにより、ユーザが素子を構成する導体部分に直接触れることを防止できる。これにより、錆などによる素子の腐食を防止できる。 As shown in FIG. 6B, by enclosing the antenna 300 in the resin case 7, it is possible to prevent the user from directly touching the conductor portion constituting the element. Thereby, corrosion of the element due to rust or the like can be prevented.
　また、図５の例と同様に、アンテナ３００を、その大きさよりも相対的に広い面積を有する誘電体素材８に近接させて配置させれば、単独で設置した場合（周囲が空気で覆われている場合）と比較して共振周波数を下げることができる。これにより、さらにアンテナを小型化することができる。このとき、アンテナは樹脂ケース７に封入されていても、されていなくてもよい。 Similarly to the example of FIG. 5, when the antenna 300 is disposed close to the dielectric material 8 having an area relatively larger than the size of the antenna 300, when the antenna 300 is installed alone (the periphery is covered with air). The resonance frequency can be lowered as compared with the case of Thereby, the antenna can be further reduced in size. At this time, the antenna may or may not be enclosed in the resin case 7.
　また、第３実施例では、図１２（ａ）に示すように、基材２４のくり抜き部２４ｃ内部にアンプ回路２７を実装することができる。これにより、アンプ回路２７を含めたアンテナ３００の厚さを薄くすることができる。図１２（ａ）の例では、アンテナ３００の素子２２及び２３により受信され、給電部２２ｓから出力された信号がアンプ回路２７により増幅され、ケーブル２７ａを通じて外部の回路へ供給される。 In the third embodiment, as shown in FIG. 12A, the amplifier circuit 27 can be mounted inside the cutout portion 24c of the base material 24. Thereby, the thickness of the antenna 300 including the amplifier circuit 27 can be reduced. In the example of FIG. 12A, a signal received by the elements 22 and 23 of the antenna 300 and output from the power feeding unit 22s is amplified by the amplifier circuit 27 and supplied to an external circuit through the cable 27a.
　また、他の例では、図１２（ｂ）に示すように、アンプ回路２８を基板２１に形成してもよい。即ち、基板２１に給電素子２２、非励振素子２３及びアンプ回路２８を形成した後、誘電体の基材２４を基板２１上に装着する。これによっても、アンプ回路２８に含まれる電子部品は基板２４のくり抜き部２４ｃ内に収まるので、アンプ回路２８を含めたアンテナ３００自体の厚さを薄くすることができる。 In another example, the amplifier circuit 28 may be formed on the substrate 21 as shown in FIG. That is, after the feeding element 22, the non-excitation element 23 and the amplifier circuit 28 are formed on the substrate 21, the dielectric base material 24 is mounted on the substrate 21. Also by this, since the electronic components included in the amplifier circuit 28 are accommodated in the cutout portion 24c of the substrate 24, the thickness of the antenna 300 itself including the amplifier circuit 28 can be reduced.
　図１３（ａ）～（ｃ）に誘電体の基材２４の変形例を示す。基材２４は、基板２１上に形成された給電素子２２のパターン上の、波長収縮効果が効果的に得られる場所をカバーすればよい。波長収縮効果が効果的に得られる場所とは、パターン間の電磁界結合が強い部分を指し、この部分をカバーすればよい。この場所はシミュレーションまたは実験により決定される。例えば、給電素子の端部付近や給電部付近は必ずしもカバーされる必要はない。よって、基材２４は、図１２（ｂ）に示すスロット型以外にも、図１３（ａ）のようなＣ字型、図１３（ｂ）のような凹字型、図１３（ｃ）のような凹字を２分割した形状などとすることができる。 FIGS. 13A to 13C show modifications of the dielectric base material 24. FIG. The base material 24 should just cover the place where the wavelength contraction effect is effectively obtained on the pattern of the power feeding element 22 formed on the substrate 21. The place where the wavelength contraction effect is effectively obtained refers to a portion where the electromagnetic field coupling between the patterns is strong, and this portion may be covered. This location is determined by simulation or experiment. For example, the vicinity of the end portion of the power feeding element and the vicinity of the power feeding portion are not necessarily covered. Therefore, the substrate 24 has a C-shape as shown in FIG. 13A, a concave shape as shown in FIG. 13B, and a slot shape shown in FIG. Such a concave character can be divided into two.
　［変形例］
　上記の実施例では、誘電体の基材１、１１、２４はいずれも長方形の平面形状であるが、本発明の適用はこれには限られない。一方向の長さが、それと垂直な方向の長さより十分に長い長手形状であれば、楕円形状や菱形の平面形状であってもよい。 [Modification]
In the above embodiment, all of the dielectric bases 1, 11, and 24 have a rectangular planar shape, but the application of the present invention is not limited to this. If the length in one direction is a longitudinal shape that is sufficiently longer than the length in the direction perpendicular thereto, an elliptical shape or a rhombic planar shape may be used.
　上記の実施例では、誘電体の基材１、１１、２４に形成されるくり抜き部１ｃ、１１ｃ、２４ｃの内部は空間となっており、空気が存在している。その代わりに、くり抜き部１ｃ、１１ｃ、２４ｃ内部に、その基材１、１１、２４の誘電率より十分に低い誘電率を有する誘電体を配置してもよい。 In the above embodiment, the hollow portions 1c, 11c, and 24c formed in the dielectric base materials 1, 11, and 24 are spaces, and air is present. Instead, a dielectric having a dielectric constant sufficiently lower than the dielectric constant of the base materials 1, 11, 24 may be disposed inside the cut-out portions 1 c, 11 c, 24 c.
　上記の実施例では、給電素子２、１２、２２は全ての部分が誘電体の基材１、１１、２４に接触しているが、これは必須ではなく、誘電体の基材は、給電素子上の波長収縮効果が得られる部分をカバーしていればよい。よって、給電素子の一部が誘電体の基材と接触していないような配置であっても構わない。 In the above embodiment, the power feeding elements 2, 12, and 22 are all in contact with the dielectric base materials 1, 11, and 24, but this is not essential, and the dielectric base material is the power feeding element. It is only necessary to cover a portion where the above wavelength contraction effect can be obtained. Therefore, the arrangement may be such that a part of the feed element is not in contact with the dielectric substrate.
　上記の実施例では、給電素子２、１２、２２はいずれも直線状であるが、本発明の適用はこれには限られない。例えば、給電素子はジグザグ形状やメアンダ（ｍｅａｎｄｅｒ）形状であってもよい。 In the above embodiment, the feed elements 2, 12, and 22 are all linear, but the application of the present invention is not limited to this. For example, the power feeding element may have a zigzag shape or a meander shape.
　上記の実施例では、誘電体の基材１、１１、２４の形状は直方体となっているが、本発明はこれには限定されない。基材は平面形状が楕円形や菱形などでも構わない。その場合、給電素子はその形状の外周に沿って配置されてもよく、長方形に配置されてもよい。 In the above embodiment, the shape of the dielectric bases 1, 11, and 24 is a rectangular parallelepiped, but the present invention is not limited to this. The base material may have an elliptical shape or a rhombus shape in plan view. In that case, the power feeding element may be disposed along the outer periphery of the shape, or may be disposed in a rectangular shape.
　本発明は、車両に搭載される地上波デジタル放送の受信アンテナに利用することができる。また、ポータブルＴＶ、ポータブルゲーム機など、小型携帯機器用の地上波デジタル放送受信用アンテナとして利用することができる。 The present invention can be used for a receiving antenna for terrestrial digital broadcasting mounted on a vehicle. It can also be used as an antenna for receiving terrestrial digital broadcasts for small portable devices such as portable TVs and portable game machines.

Claims (10)

  1. 　長手形状であり、外周部と中心部とで誘電率が異なる第１の基材と、
    　前記第１の基材の外周部と少なくとも接しており、かつ、前記外周部の形状に沿うように配置されている給電素子と、
    　前記給電素子と近接配置されている非励振素子と、を備えることを特徴とする長手形状アンテナ。     A first base material having a longitudinal shape and having a different dielectric constant between an outer peripheral portion and a central portion;
    A power feeding element that is at least in contact with the outer peripheral portion of the first base material and is arranged so as to follow the shape of the outer peripheral portion;
    A longitudinal antenna, comprising: the feed element and a non-excitation element arranged in proximity.
  2. 　前記第１の基材は、前記中心部がくりぬかれていることを特徴とする請求項１に記載の長手形状アンテナ。 The longitudinal antenna according to claim 1, wherein the central portion of the first base material is hollowed out.
  3. 　前記第１の基材は、長手方向の中央における前記外周部の一部が切断されたＣ字型平面形状を有することを特徴とする請求項２に記載の長手形状アンテナ。 3. The longitudinal antenna according to claim 2, wherein the first base material has a C-shaped planar shape in which a part of the outer peripheral portion at the center in the longitudinal direction is cut.
  4. 　前記給電素子は、前記第１の基材の短手方向において前記外周部と接している部分の幅が、前記第１の基材の長手方向において前記外周部と接している部分の幅より大きいことを特徴とする請求項１乃至３のいずれか一項に記載の長手形状アンテナ。 In the power feeding element, the width of the portion in contact with the outer peripheral portion in the short direction of the first base material is larger than the width of the portion in contact with the outer peripheral portion in the longitudinal direction of the first base material. The longitudinal antenna according to claim 1, wherein the antenna is a longitudinal antenna.
  5. 　前記給電素子は、前記第１の基材の短手方向において前記外周部と接している部分が複数に分岐していることを特徴とする請求項１乃至４のいずれか一項に記載の長手形状アンテナ。 5. The longitudinal direction according to claim 1, wherein a portion of the power feeding element that is in contact with the outer peripheral portion in a short direction of the first base material is branched into a plurality of portions. Shape antenna.
  6. 　前記第１の基材の外周部の誘電率より低い誘電率を有する第２の基材を備え、
    　前記給電素子及び前記非励振素子は、前記第２の基材に形成されていることを特徴とする請求項１乃至５のいずれか一項に記載の長手形状アンテナ。     Comprising a second substrate having a dielectric constant lower than the dielectric constant of the outer periphery of the first substrate;
    The longitudinal antenna according to claim 1, wherein the feeding element and the non-excitation element are formed on the second base material.
  7. 　前記給電素子の給電部と、前記給電素子の２つの端部とは、前記第２の基材の長手方向における中央位置近傍で相互に対向配置されていることを特徴とする請求項１乃至７のいずれか一項に記載の長手形状アンテナ。 The power feeding portion of the power feeding element and the two end portions of the power feeding element are arranged to face each other in the vicinity of the center position in the longitudinal direction of the second base material. The longitudinal antenna according to any one of the above.
  8. 　前記給電素子は、前記給電素子の２つの端部付近又は前記給電部付近を除く場所において、前記第１の基材と接していることを特徴とする請求項１乃至７のいずれか一項に記載の長手形状アンテナ。 8. The feed element according to claim 1, wherein the feed element is in contact with the first base material at a place near two end portions of the feed element or near the feed section. 9. The described longitudinal antenna.
  9. 　樹脂製のケースに封入されていることを特徴とする請求項１乃至８のいずれか一項に記載の長手形状アンテナ。 The longitudinal antenna according to any one of claims 1 to 8, wherein the antenna is encapsulated in a resin case.
  10. 　前記第１の基材の面積よりも広い面積を有する誘電体に近接配置されていることを特徴とする請求項１乃至９のいずれか一項に記載の長手形状アンテナ。 The longitudinal antenna according to any one of claims 1 to 9, wherein the antenna is disposed close to a dielectric having an area larger than an area of the first base material.
PCT/JP2008/065546 2008-08-29 2008-08-29 Elongated antenna WO2010023752A1 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
PCT/JP2008/065546 WO2010023752A1 (en) 2008-08-29 2008-08-29 Elongated antenna
JP2010526472A JPWO2010023752A1 (en) 2008-08-29 2008-08-29 Longitudinal antenna
EP08809613A EP2330686A1 (en) 2008-08-29 2008-08-29 Elongated antenna

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/JP2008/065546 WO2010023752A1 (en) 2008-08-29 2008-08-29 Elongated antenna

Publications (1)

Publication Number Publication Date
WO2010023752A1 true WO2010023752A1 (en) 2010-03-04

Family

ID=41720941

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/JP2008/065546 WO2010023752A1 (en) 2008-08-29 2008-08-29 Elongated antenna

Country Status (3)

Country Link
EP (1) EP2330686A1 (en)
JP (1) JPWO2010023752A1 (en)
WO (1) WO2010023752A1 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5025785B1 (en) * 1969-10-09 1975-08-26
JPS60129708U (en) * 1984-02-09 1985-08-30 日本アンテナ株式会社 antenna
JPH0738325A (en) * 1993-07-19 1995-02-07 Hitachi Cable Ltd Wide band dipole antenna
WO2001018909A1 (en) * 1999-09-09 2001-03-15 Murata Manufacturing Co., Ltd. Surface-mount antenna and communication device with surface-mount antenna
JP2002217628A (en) 2001-01-16 2002-08-02 Furukawa Electric Co Ltd:The Miniature antenna
JP2004032776A (en) * 2002-06-27 2004-01-29 Harris Corp Dipole antenna using dielectric substrate of composite material
JP2005303637A (en) 2004-04-09 2005-10-27 Furukawa Electric Co Ltd:The Multi-frequency common antenna and miniaturized antenna

Family Cites Families (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2003324310A (en) * 2002-05-01 2003-11-14 Furukawa Electric Co Ltd:The Small-sized antenna
JP3825400B2 (en) * 2002-12-13 2006-09-27 京セラ株式会社 Antenna device
JP2006303946A (en) * 2005-04-21 2006-11-02 Ngk Spark Plug Co Ltd Antenna and antenna adjusting method
JP4132063B2 (en) * 2006-05-29 2008-08-13 京セラ株式会社 Surface mount antenna, antenna device, and resonance frequency adjusting method

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5025785B1 (en) * 1969-10-09 1975-08-26
JPS60129708U (en) * 1984-02-09 1985-08-30 日本アンテナ株式会社 antenna
JPH0738325A (en) * 1993-07-19 1995-02-07 Hitachi Cable Ltd Wide band dipole antenna
WO2001018909A1 (en) * 1999-09-09 2001-03-15 Murata Manufacturing Co., Ltd. Surface-mount antenna and communication device with surface-mount antenna
JP2002217628A (en) 2001-01-16 2002-08-02 Furukawa Electric Co Ltd:The Miniature antenna
JP2004032776A (en) * 2002-06-27 2004-01-29 Harris Corp Dipole antenna using dielectric substrate of composite material
JP2005303637A (en) 2004-04-09 2005-10-27 Furukawa Electric Co Ltd:The Multi-frequency common antenna and miniaturized antenna

Also Published As

Publication number Publication date
JPWO2010023752A1 (en) 2012-01-26
EP2330686A1 (en) 2011-06-08

Similar Documents

Publication Publication Date Title
US9246210B2 (en) Antenna with cover radiator and methods
US6903692B2 (en) Dielectric antenna
EP0829110B1 (en) Printed monopole antenna
US7978141B2 (en) Couple-fed multi-band loop antenna
EP0757405B1 (en) Antenna
KR100707242B1 (en) Dielectric chip antenna
US6995714B2 (en) Internal triple-band antenna
JP4332494B2 (en) Antenna device
US7821469B2 (en) Printed antenna
JP2007089234A (en) Antenna
US20050174296A1 (en) Antenna and wireless communications device having antenna
WO2010007823A1 (en) Multi-resonant antenna
EP1459410B1 (en) High-bandwidth multi-band antenna
US20200295449A1 (en) Antenna device
JP2011035519A (en) Antenna device
WO2001099228B1 (en) An antenna for a portable communication apparatus, and a portable communication apparatus comprising such an antenna
US7542002B1 (en) Wideband monopole antenna
GB2409772A (en) Low profile antenna with end fed antenna trace formed upon a dielectric block mounted above PCB ground plane
JP4992762B2 (en) Automotive integrated antenna
JP2009194783A (en) Pattern antenna and antenna apparatus with pattern antenna mounted on master substrate
US20100253580A1 (en) Printed antenna and electronic device employing the same
WO2010023752A1 (en) Elongated antenna
JP2003133838A (en) Monopole antenna
JP5461248B2 (en) antenna
WO2021214959A1 (en) Array antenna device

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 08809613

Country of ref document: EP

Kind code of ref document: A1

WWE Wipo information: entry into national phase

Ref document number: 2010526472

Country of ref document: JP

WWE Wipo information: entry into national phase

Ref document number: 2008809613

Country of ref document: EP

NENP Non-entry into the national phase

Ref country code: DE