WO2004025781A1 - Loop antenna - Google Patents

Loop antenna Download PDF

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Publication number
WO2004025781A1
WO2004025781A1 PCT/JP2003/011774 JP0311774W WO2004025781A1 WO 2004025781 A1 WO2004025781 A1 WO 2004025781A1 JP 0311774 W JP0311774 W JP 0311774W WO 2004025781 A1 WO2004025781 A1 WO 2004025781A1
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WO
WIPO (PCT)
Prior art keywords
radiation conductor
loop
loop antenna
conductor
dielectric
Prior art date
Application number
PCT/JP2003/011774
Other languages
French (fr)
Japanese (ja)
Inventor
Masanori Waki
Hiroyuki Tamaoka
Original Assignee
The Furukawa Electric Co., Ltd
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 The Furukawa Electric Co., Ltd filed Critical The Furukawa Electric Co., Ltd
Publication of WO2004025781A1 publication Critical patent/WO2004025781A1/en

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Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01Q—ANTENNAS, i.e. RADIO AERIALS
    • H01Q1/00—Details of, or arrangements associated with, antennas
    • H01Q1/12—Supports; Mounting means
    • H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
    • H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
    • H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
    • H01Q1/242—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for hand-held use
    • 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
    • H01Q7/00—Loop antennas with a substantially uniform current distribution around the loop and having a directional radiation pattern in a plane perpendicular to the plane of the loop

Definitions

  • the present invention relates to a loop antenna, and more particularly to a small loop antenna mounted on a communication device such as a mobile phone.
  • monopole antennas, helical antennas, and the like have been used in mobile phones and the like.
  • the characteristics such as narrowing of the band will be deteriorated, so that the antenna cannot be mounted adjacent to the board. It was mounted in a form that jumped out. Therefore, there are antennas that originally have a narrow band, but have a wider inverted F-type antenna that can be mounted inside the housing.
  • This inverted F-type antenna has a wide band by modifying the shape of the radiating conductor to form a reactance compensation circuit.
  • the loop antenna is less susceptible to the surroundings, but requires a radiating conductor length of one wavelength, and tends to be larger than monopole antennas, helical antennas, and inverted F antennas, which require a radiating conductor length of 1Z4 wavelength. Some have been devised to reduce size.
  • This loop antenna is realized with dimensions of a parallel part length of 3 Omm, a spiral part diameter of 4 mm, and a rising height of 8 mm to create an antenna for 1.8 GHz (see Japanese Patent Application Laid-Open No. 2001-284935). ).
  • an object of the present invention is to provide a loop antenna that is further downsized while securing a band that is practically satisfactory. Disclosure of the invention
  • a loop antenna includes a loop antenna in which a radiation conductor is formed in a loop shape, one end is fed, and the other end is connected to a ground conductor.
  • the radiation conductor on the loop is provided with a meander part in which a part of the loop-shaped radiation conductor is formed in a meander shape, and a wide part in which the other part is formed wide.
  • the length of the loop is increased by making a part of it a meander shape, so the external dimensions can be reduced while securing the loop length for approximately one wavelength of the resonance frequency.
  • the ground conductor may be provided in an appropriate space in the communication device regardless of the position of the loop antenna.
  • the layout in the communication device has a high degree of freedom, and as a result, the communication device can be made compact. Further, since the other part of the loop-shaped radiation conductor is formed wider, a wider band can be realized.
  • the loop antenna also resonates at an even multiple of the fundamental resonance frequency, so when it is necessary to resonate at a certain frequency and twice that frequency, for example, the GSM900MHz And DCS 1800 MHz and wireless LAN 2.5 GHz and 5 GHz,
  • the loop antenna according to the present invention is characterized in that the radiation conductor is formed three-dimensionally.
  • the loop antenna is formed in an L-shape or a U-shape according to the surrounding shape where the antenna is grounded, so that the space in a communication device such as a mobile phone in which the antenna is mounted is effectively used. This makes it possible to make the communication device compact.
  • the radiating conductor is formed on a dielectric. It is characterized by having been done.
  • the length of the radiation conductor can be reduced for a predetermined resonance frequency due to the wavelength shortening effect of the dielectric, and the loop antenna can be configured more compactly.
  • the strength of the antenna can be ensured by the dielectric.
  • the loop antenna according to the present invention is characterized in that the radiation conductor is formed by being divided on a plurality of surfaces of a dielectric.
  • a radiating conductor is formed on the front surface and the back surface of a plate-shaped dielectric via a side surface, or a radiating conductor is formed on the upper surface and a side surface of a rectangular dielectric.
  • the loop antenna according to the present invention is characterized in that the meander portion is formed on one surface side of the plate-shaped dielectric, and the wide portion is formed on another surface located on the back side of the plate-shaped dielectric.
  • the present inventors have found that although it is effective to form the radiation conductor in a meander shape in order to increase the length of the radiation conductor while suppressing the external dimensions of the antenna, I found that there was an evil.
  • the meandering portions of the loop antenna portions are close to each other, the characteristics will deteriorate, such as narrowing of the band. This deterioration of characteristics becomes more remarkable when meander portions that are far from each other in circuit are close to each other. This is thought to be because the phases of the currents flowing in the adjacent meander portions are different from each other, and when the portions having large changes approach each other, they are susceptible to each other and unnecessary electrical coupling increases.
  • the loop antenna can be made compact.
  • the radiating conductors By arranging the radiating conductors on the front and back, only one of the radiating conductor on the front side and the radiating conductor on the back side (for example, the front side), which is far from the circuit but is physically close, is meandered.
  • the meander portion is prevented from approaching, thereby avoiding the above-mentioned characteristics.
  • the radiation conductor on the surface for example, the back surface, a wide band can be realized, and a suitable loop antenna can be configured.
  • the loop antenna according to the present invention is characterized in that a dielectric is further disposed on the radiation conductor.
  • the length of the radiation conductor can be shortened for a predetermined resonance frequency due to the wavelength shortening effect of the dielectric.
  • the loop antenna can be configured to be smaller. 'Furthermore, since the radiation conductor is not exposed, the radiation conductor can be protected from damage and oxidation.
  • the loop antenna according to the present invention may be configured such that a part of the radiation conductor is formed on a substrate, a remaining part of the radiation conductor is formed separately, and a part of the radiation conductor formed separately. Is mounted on the substrate to form a desired radiation conductor.
  • a radiation conductor of a loop antenna is formed by integrating a radiation conductor of a chip antenna such as a monoponol type antenna which is a general-purpose component and a radiation conductor provided on a substrate.
  • a loop antenna can be configured.
  • FIG. 1 is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention.
  • FIG. 2 is a diagram showing a configuration of a loop antenna according to another embodiment of the present invention.
  • FIG. 3 is a perspective view showing a front surface and a back surface of a loop antenna according to still another embodiment of the present invention.
  • FIG. 4 is a diagram showing a configuration of a loop antenna according to still another embodiment of the present invention.
  • FIG. 5 is a perspective view showing a configuration of a loop antenna according to still another embodiment of the present invention.
  • FIG. 6 is an exploded perspective view of a loop antenna according to still another embodiment of the present invention.
  • FIG. 7 is a perspective view showing a configuration of a mobile phone equipped with the loop antenna according to the present invention.
  • FIG. 1 is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention.
  • FIG. 2 is a diagram showing a configuration of a loop antenna according to another embodiment of the present invention.
  • FIG. 8 is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention.
  • No. FIG. 9 is a diagram illustrating reflection characteristics of the loop antenna according to the embodiment of the present invention.
  • FIG. 10 is a diagram showing a radiation pattern at 92 OMHz of the loop antenna according to the embodiment of the present invention.
  • FIG. 11 is a diagram showing a radiation pattern at 179 MHz of the loop antenna according to the embodiment of the present invention.
  • FIG. 1 (a) is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention.
  • a loop antenna 30 has a radiation conductor 1, a feed terminal 4, and a ground terminal 5.
  • the radiation conductor 1 has a meander portion 2 and a wide portion 3.
  • the power supply terminal 4 is connected to the inner conductor 7 of the coaxial cable 6, and the ground terminal 5 is connected to the outer conductor 8 of the coaxial cable 6.
  • FIGS. 2 (a) and 2 (b) are diagrams showing a configuration of a loop antenna according to another embodiment of the present invention.
  • the radiating conductor 1 has an L-shape (FIG.
  • FIG. 3 is a diagram showing a configuration of a loop antenna according to the embodiment of the present invention.
  • the radiating conductor 1 is formed on one surface of a plate-shaped dielectric 9. As a result, a predetermined resonance frequency is obtained due to the wavelength shortening effect of the dielectric 9. The length of the radiation conductor 1 can be made shorter with respect to the wave number, and the strength can be ensured.
  • the dielectric 9 is formed in an L shape, and the radiation conductor 1 is formed on two surfaces of the dielectric 9, thereby avoiding interference of the components 22 and the like, and forming a loop.
  • the antenna 30 can be efficiently arranged.
  • FIG. 3 (c) when the dielectric 9 is formed in a rectangular shape and the radiation conductor 1 is formed on a plurality of surfaces, the volume of the dielectric 9 is large, so that the wavelength shortening effect is reduced. As a result, the loop antenna 30 can be made compact.
  • parts common to FIG. 1 are denoted by the same reference numerals as in FIG.
  • FIG. 4 shows still another embodiment of the present invention.
  • FIG. 4 (a) is a perspective view showing the front surface of the loop antenna 30, and
  • FIG. 4 (b) is a perspective view showing the back surface of the loop antenna 30.
  • the dielectric 9 is formed in a plate shape, and on one surface (surface), the meander portion 2, the power supply terminal 4, and the A ground terminal 5 is provided, and a wide portion 3 is provided on the other surface (back surface).
  • the meander portion 2 and the wide portion 3 are connected by a conductor connecting portion 10 provided on a side surface of the dielectric 9 to form a loop.
  • the radiation conductor 1 is efficiently arranged on the dielectric 9, the meander portions 2 are prevented from approaching each other, and the antenna characteristics are not deteriorated.
  • FIG. 5 shows still another embodiment of the present invention.
  • the radiation conductor 1 is covered with a dielectric 9, and the feed terminal 4 and the ground terminal 5 are exposed from the dielectric 9.
  • the wavelength shortening effect of the dielectric 9 can be enhanced, and the radiation conductor 1 can be protected from external damage and oxidation.
  • FIG. 6 is a diagram showing still another embodiment of the present invention.
  • reference numeral 11 denotes a general-purpose monopole chip antenna, in which a meandering radiation conductor 12 is formed on a dielectric 17 and terminals 13 and 15 are provided.
  • substrate 18 has a width The wide part 3, the power supply terminal 4, the ground terminal 5, and the terminal connection parts 14 and 16 are formed.
  • a loop leading to the radiation conductor 12—terminal 15—terminal connection part 16—wide part 3—ground terminal 5 is formed, enabling operation as a loop antenna.
  • FIG. 7 is a perspective view showing a state where the loop antenna according to the present invention is mounted on a mobile phone. 7 (a) and the side of the mobile phone 20 shown in FIG. 7 (b), the no-repeat antenna 30 has a slight difference between the housing of the mobile phone 20 and the substrate 21. It can be mounted in gaps, which contributes to the downsizing of mobile phones, improved usability by eliminating protrusions, and improved design.
  • loop antennas shown in FIGS. 8 (a) to 8 (e) were prepared and their characteristics were measured.
  • a conductor thickness of 0.8 mm and a meander spacing of 1.0 mm are formed on the surface of a 70 ⁇ m thick copper foil on a substrate with a length of 28 mm, a width of 10 mm, a thickness of 1.6 mm, and a dielectric constant of 3.9.
  • a meander (only 1.1 mm at both ends) was formed, the copper foil was applied to the entire back surface to make a wide portion, and a conductor connection portion having a width of lmm was provided on the dielectric side surface.
  • 8 (a) is a plan view, FIG.
  • FIG. 8 (b) is a right side view
  • FIG. 8 (c) is a front view
  • FIG. 8 (d) is a back view
  • Yes Fig. 8 (e) is a rear view.
  • VSWR and Smith charts measured by a network analyzer are shown in Fig. 7 (a) for the reflection characteristics when this norepe antenna is placed as shown in Fig. 7 (a) on a finite ground plane of 40mm width and 110mm length.
  • Figures 9 (a) and 9 (b) are shown.
  • Fig. 9 (a) is the VSWR chart
  • Fig. 9 (b) is the Smith chart.
  • a dipole antenna was placed on the transmitting side, and the antenna of the present invention mounted on a rotatable table was placed on the receiving side.
  • the patterns are shown in Figs. 10 (a) to 10 (c), and the emission patterns at a frequency of 1795MHz are shown in Figs. 11 (a) to 10 (c).
  • 10 (a) and 11 (a) show the directivity in the xy plane
  • FIGS. 10 (b) and 11 (b) show the directivity in the yz plane.
  • FIG. 10 (c) and FIG. 11 (c) show the z X-plane ⁇ directivity.
  • the characteristics are as follows: the frequency is 880 to 96 OMHz, and the frequency is 1710 to: 1880 MHz, the VSWR is 3 or less, the maximum gain is +1.85 dBi (when transmitting and receiving at 920 MHz), An antenna with 55 dBi (1795 MHz transmission / reception), radiation efficiency 56% (920 MHz transmission / reception), 51% (1795 MHz transmission / reception) with dimensions of 28 mm long x 1 Omm x 1.6 mm thick was completed.

Abstract

A loop antenna (30) where a radiation conductor (1) is shaped into a loop, power is supplied to one end side through a power supply terminal (4) and the other end side is connected with an earth conductor through an earth terminal (5). The size of the loop antenna is reduced furthermore while ensuring a practically satisfiable band by providing a meander part (2) at a part of the loop radiation conductor and a wide part (3) at other part of the loop radiation conductor.

Description

明 細 書 ループアンテナ 技術分野  Description Loop antenna Technical field
この発明は、 ループアンテナに関し、 特に、 携帯電話等の通信機に搭載する小 型のループアンテナに関するものである。 背景技術  The present invention relates to a loop antenna, and more particularly to a small loop antenna mounted on a communication device such as a mobile phone. Background art
従来から、 携帯電話などにおいては、 モノポールアンテナ、 ヘリカルアンテナ などが使用されている。 し力 し、 モノポ ルアンテナやへリカルアンテナは、 ァ ンテナ本体を基板に近づけると帯域が狭くなるなどの特性の悪化が起こるため、 基板の近くに隣接して実装することができず、 筐体の外に飛び出す形で実装され ていた。 そこで、 元々帯域の狭いアンテナではあるが、 筐体の内部に実装が可能 な逆 F型のアンテナの広帯域化を図ったものがある。 この逆 F型アンテナは、 放 射導体形状に工夫を施し、 リアクタンス補償回路を構成し、 広帯域としている。 そして、 88MHz用VSWR=2で帯域幅3 OMH zのアンテナを作成するの に、 長さ 35mmX幅 15mmX厚さ 5mmの寸法で実現している （たとえば、 特開平 6 -97725号公報参照） 。  Conventionally, monopole antennas, helical antennas, and the like have been used in mobile phones and the like. However, when a monopole antenna or a helical antenna is brought close to the board, the characteristics such as narrowing of the band will be deteriorated, so that the antenna cannot be mounted adjacent to the board. It was mounted in a form that jumped out. Therefore, there are antennas that originally have a narrow band, but have a wider inverted F-type antenna that can be mounted inside the housing. This inverted F-type antenna has a wide band by modifying the shape of the radiating conductor to form a reactance compensation circuit. In order to create an antenna having a bandwidth of 3 OMHz with a VSWR of 88 MHz and a bandwidth of 2 MHz, it is realized with dimensions of 35 mm in length, 15 mm in width and 5 mm in thickness (for example, see Japanese Patent Application Laid-Open No. 6-97725).
また、 周囲の影響を受けにくいが放射導体の長さが 1波長必要であり、 放射導 体長さが 1Z4波長で足りるモノポールアンテナ、 ヘリカルアンテナ、 逆 Fアン テナに比べ、 大型となりがちなループアンテナに工夫を施し、 小型化を図ったも のもある。 このループアンテナは、 1. 8 GHz用のアンテナを作成するのに、 平行部長さ 3 Omm、 螺旋部径 4mm、 立ち上がり高さ 8 mmの寸法で実現して いる （特開 2001— 284935号公報参照） 。  In addition, the loop antenna is less susceptible to the surroundings, but requires a radiating conductor length of one wavelength, and tends to be larger than monopole antennas, helical antennas, and inverted F antennas, which require a radiating conductor length of 1Z4 wavelength. Some have been devised to reduce size. This loop antenna is realized with dimensions of a parallel part length of 3 Omm, a spiral part diameter of 4 mm, and a rising height of 8 mm to create an antenna for 1.8 GHz (see Japanese Patent Application Laid-Open No. 2001-284935). ).
し力 しながら、 従来のアンテナは、 なお相当の大きさを有しており、 携帯電話 などの通信機器の小型化、 使い勝手の向上、 意匠性の向上などからアンテナにも 更なる小型化の要請が課されている。 However, conventional antennas still have a considerable size, and the size of communication devices such as mobile phones, the usability, and the design have been improved. There is a demand for further miniaturization.
そこで、 この発明の目的は、 実用上満足できる帯域を確保しつつ、 更なる小型 化を図ったループアンテナを提供することである。 発明の開示  Accordingly, an object of the present invention is to provide a loop antenna that is further downsized while securing a band that is practically satisfactory. Disclosure of the invention
上述した課題を解決し、 目的を達成するため、 この発明にかかるループアンテ ナは、 放射導体をループ状に形成し、 一端側に給電し、 他端側を接地導体に接続 したループアンテナにおいて、 ループ状の放射導体の一部をミアンダ状に形成し たミアンダ部と、 他の一部を幅広に形成した幅広部とを備えたことを特徴とする この発明によれば、 ループ上の放射導体の一部をミァンダ状にして長さを稼い でいるため、 ループ長さを共振周波数の略 1波長分確保しながらも、 外形寸法を 小型にすることができる。 また、 接地導体は、 ループアンテナの位置に拘わらず 、 通信機内の適宜なスペースに設ければよいので、 通信機内のレイアウトの自由 度が高く、 結果的に通信機を小型に構成できる。 さらに、 ループ状の放射導体の 他の一部を幅広に形成したため、 広帯域化が実現できる。 なお、 ループ型アンテ ナは、 基本共振周波数の偶数倍の周波数にも共振するため、 ある周波数とその 2 倍の周波数で共振する必要がある場合、 たとえば、 携帯電話の G SM 9 0 0 MH zと D C S 1 8 0 0 MH zや無線 L ANの 2 . 5 GH zと 5 GH zの場合には、 In order to solve the above-described problems and achieve the object, a loop antenna according to the present invention includes a loop antenna in which a radiation conductor is formed in a loop shape, one end is fed, and the other end is connected to a ground conductor. According to the present invention, the radiation conductor on the loop is provided with a meander part in which a part of the loop-shaped radiation conductor is formed in a meander shape, and a wide part in which the other part is formed wide. The length of the loop is increased by making a part of it a meander shape, so the external dimensions can be reduced while securing the loop length for approximately one wavelength of the resonance frequency. In addition, the ground conductor may be provided in an appropriate space in the communication device regardless of the position of the loop antenna. Therefore, the layout in the communication device has a high degree of freedom, and as a result, the communication device can be made compact. Further, since the other part of the loop-shaped radiation conductor is formed wider, a wider band can be realized. The loop antenna also resonates at an even multiple of the fundamental resonance frequency, so when it is necessary to resonate at a certain frequency and twice that frequency, for example, the GSM900MHz And DCS 1800 MHz and wireless LAN 2.5 GHz and 5 GHz,
2周波共用アンテナとしても使用できる。 It can also be used as a dual frequency antenna.
また、 この s明にかかるループアンテナは、 前記放射導体が三次元に形成され たことを特 s [とする。  Further, the loop antenna according to the present invention is characterized in that the radiation conductor is formed three-dimensionally.
この発明によれば、 了ンテナが接地される周囲形状に合わせてループアンテナ を L字型やコの字型に形成することによって、 アンテナが搭載される携帯電話な どの通信機器内のスペースを有効に利用して通信機を小型に構成することができ る。  According to the present invention, the loop antenna is formed in an L-shape or a U-shape according to the surrounding shape where the antenna is grounded, so that the space in a communication device such as a mobile phone in which the antenna is mounted is effectively used. This makes it possible to make the communication device compact.
また、 この発明にかかるループアンテナは、 前記放射導体が誘電体上に形成さ れたことを特徴とする。 Further, in the loop antenna according to the present invention, the radiating conductor is formed on a dielectric. It is characterized by having been done.
この発明によれば、 誘電体の波長短縮効果によって、 所定の共振周波数に対し て放射導体の長さを短くすることができ、 ループアンテナを、 より小型に構成で きる。 また、 放射導体として金属泊等を使用した場合でも、 誘電体によってアン テナの強度を確保することができる。  According to the present invention, the length of the radiation conductor can be reduced for a predetermined resonance frequency due to the wavelength shortening effect of the dielectric, and the loop antenna can be configured more compactly. In addition, even when a metal stay or the like is used as the radiation conductor, the strength of the antenna can be ensured by the dielectric.
また、 この発明にかかるループアンテナは、 前記放射導体が誘電体の複数面上 に分割して形成されたことを特徴とする。  Further, the loop antenna according to the present invention is characterized in that the radiation conductor is formed by being divided on a plurality of surfaces of a dielectric.
この発明によれば、 たとえば板状の誘電体の表面おょぴ裏面に側面を介して放 射導体を形成したり、 矩形状誘電体の上面および側面に放射導体を形成して、 誘 電体の複数面を有効に利用することによって、 ループアンテナを小型に構成でき る。 ，  According to the present invention, for example, a radiating conductor is formed on the front surface and the back surface of a plate-shaped dielectric via a side surface, or a radiating conductor is formed on the upper surface and a side surface of a rectangular dielectric. By making effective use of the multiple surfaces, the loop antenna can be made compact. ,
また、 この発明にかかるループアンテナは、 前記ミアンダ部を板状誘電体の一 面側に形成し、 前記幅広部を前記板状誘電体の裏側に位置する他の面に形成した ことを特敷とする。  Further, the loop antenna according to the present invention is characterized in that the meander portion is formed on one surface side of the plate-shaped dielectric, and the wide portion is formed on another surface located on the back side of the plate-shaped dielectric. And
ここで、 本発明者らは、 鋭意検討の結果、 アンテナの外形寸法を抑えつつ放射 導体の長さを稼ぐには、 放射導体をミアンダ状に形成することが有効ではあるも のの、 以下の弊害があることを見出した。 すなわち、 ループアンテナの部分のう ち、 ミアンダ状の部分同士が近接すると、 帯域が狭くなるなどの特性の悪化が起 こる。 この特性の悪化は、 回路的に遠いミアンダ部分同士が近接するときに、 よ り顕著となる。 これは、 近接したミアンダ部分を流れる電流の位相が互いに異な り、 しかもその変化の大きい部分同士が近接することによって互いの影響を受け やすくなり、 不要な電気的結合が増加するためと考えられる。  Here, as a result of diligent studies, the present inventors have found that although it is effective to form the radiation conductor in a meander shape in order to increase the length of the radiation conductor while suppressing the external dimensions of the antenna, I found that there was an evil. In other words, if the meandering portions of the loop antenna portions are close to each other, the characteristics will deteriorate, such as narrowing of the band. This deterioration of characteristics becomes more remarkable when meander portions that are far from each other in circuit are close to each other. This is thought to be because the phases of the currents flowing in the adjacent meander portions are different from each other, and when the portions having large changes approach each other, they are susceptible to each other and unnecessary electrical coupling increases.
このため、 この発明によれば、 板状誘電体の表裏両面に放射導体を形成してい るので、 ループアンテナを小型に構成できる。 そして、 表裏に放射導体を配置す ることによって、 回路的には遠いが物理的には近接することになる表面の放射導 体と裏面の放射導体の一方のみ （たとえば表面側） をミアンダ状にして、 ミアン ダ部分が近接しないようにして、 上記特性の悪ィ匕を回避している。 さらに、 他方 の面、 たとえば裏面の放射導体を幅広にすることで広帯域ィヒが実現でき、 好適な ループアンテナを構成できる。 For this reason, according to the present invention, since the radiation conductors are formed on both the front and back surfaces of the plate-shaped dielectric, the loop antenna can be made compact. By arranging the radiating conductors on the front and back, only one of the radiating conductor on the front side and the radiating conductor on the back side (for example, the front side), which is far from the circuit but is physically close, is meandered. Thus, the meander portion is prevented from approaching, thereby avoiding the above-mentioned characteristics. Furthermore, on the other hand By widening the radiation conductor on the surface, for example, the back surface, a wide band can be realized, and a suitable loop antenna can be configured.
また、 この発明にかかるループアンテナは、 前記放射導体上にさらに誘電体を 配置したことを特徴とする。  Further, the loop antenna according to the present invention is characterized in that a dielectric is further disposed on the radiation conductor.
この発明によれば、 ループアンテナの放射導体は、 誘電体に囲まれることとな るので、 誘電体の波長短縮効果によって、 所定の共振周波数に対して放射導体の 長さを短くすることができ、 ループアンテナを、 一層小型に構成できる。'さらに 、 放射導体が露出していないので、 放射導体を外傷や酸化などから保護すること ができる。  According to the present invention, since the radiation conductor of the loop antenna is surrounded by the dielectric, the length of the radiation conductor can be shortened for a predetermined resonance frequency due to the wavelength shortening effect of the dielectric. The loop antenna can be configured to be smaller. 'Furthermore, since the radiation conductor is not exposed, the radiation conductor can be protected from damage and oxidation.
また、 この発明にかかるループアンテナは、 前記放射導体の一部を基板上に形 成し、 前記放射導体の残りの一部を別体に形成し、 前記別体に形成した放射導体 の一部を前記基板に載置することによつて所望の放射導体を形成することを特徴 とする。  In addition, the loop antenna according to the present invention may be configured such that a part of the radiation conductor is formed on a substrate, a remaining part of the radiation conductor is formed separately, and a part of the radiation conductor formed separately. Is mounted on the substrate to form a desired radiation conductor.
この発明によれば、 汎用部品であるモノポーノレ型ァンテナなどのチップ状ァン テナの放射導体と基板上に設けた放射導体を一体にしてループアンテナの放射導 体を形成して、 この発明にかかるループアンテナを構成することができる。 図面の簡単な説明  According to the present invention, a radiation conductor of a loop antenna is formed by integrating a radiation conductor of a chip antenna such as a monoponol type antenna which is a general-purpose component and a radiation conductor provided on a substrate. A loop antenna can be configured. BRIEF DESCRIPTION OF THE FIGURES
第 1図は、 この発明の実施の形態であるループアンテナの構成を示す図である 。 第 2図は、 この発明の別の実施の形態であるループアンテナの構成を示す図で ある。 第 3図は、 この発明のさらに別の実施の形態であるループアンテナの表面 および裏面を示す斜視図である。 第 4図は、 この発明のさらに別の実施の形態で あるループアンテナの構成を示す図である。 第 5図は、 この発明のさら別の実施 の形態であるループアンテナの構成を示す斜視図である。 第 6図は、 この発明の さらに別の実施の形態であるループアンテナの分解斜視図である。 第 7図は、 こ の発明にかかるループアンテナが搭載された携帯電話の構成を示す斜視図である 。 第 8図は、 この発明の実施例であるループアンテナの構成を示す図である。 第 9図は、 この発明の実施例にかかるループアンテナの反射特性を示す図である。 第 1 0図は、 この発明の実施例にかかるループアンテナの 9 2 O MH zにおける 放射パターンを示す図である。 第 1 1図は、 この発明の実施例にかかるループア ンテナの 1 7 9 5 MH zにおける放射パターンを示す図である。 発明を実施するための最良の形態 FIG. 1 is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention. FIG. 2 is a diagram showing a configuration of a loop antenna according to another embodiment of the present invention. FIG. 3 is a perspective view showing a front surface and a back surface of a loop antenna according to still another embodiment of the present invention. FIG. 4 is a diagram showing a configuration of a loop antenna according to still another embodiment of the present invention. FIG. 5 is a perspective view showing a configuration of a loop antenna according to still another embodiment of the present invention. FIG. 6 is an exploded perspective view of a loop antenna according to still another embodiment of the present invention. FIG. 7 is a perspective view showing a configuration of a mobile phone equipped with the loop antenna according to the present invention. FIG. 8 is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention. No. FIG. 9 is a diagram illustrating reflection characteristics of the loop antenna according to the embodiment of the present invention. FIG. 10 is a diagram showing a radiation pattern at 92 OMHz of the loop antenna according to the embodiment of the present invention. FIG. 11 is a diagram showing a radiation pattern at 179 MHz of the loop antenna according to the embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION
以下に添付図面を参照して、 この発明にかかるループアンテナについて説明す る。'第 1図 （a ) は、 この発明の実施の形態であるループアンテナの構成を示す 図である。 第 1図 （a ) において、 ループアンテナ 3 0は、 放射導体 1、 給電端 子 4、 および接地端子 5を有する。 放射導体 1は、 ミアンダ部 2、 幅広部 3を有 している。 給電端子 4は、 同軸ケーブル 6の内部導体 7に接続され、 接地端子 5 は、 同軸ケーブル 6の外部導体 8と接続される。  Hereinafter, a loop antenna according to the present invention will be described with reference to the accompanying drawings. FIG. 1 (a) is a diagram showing a configuration of a loop antenna according to an embodiment of the present invention. In FIG. 1A, a loop antenna 30 has a radiation conductor 1, a feed terminal 4, and a ground terminal 5. The radiation conductor 1 has a meander portion 2 and a wide portion 3. The power supply terminal 4 is connected to the inner conductor 7 of the coaxial cable 6, and the ground terminal 5 is connected to the outer conductor 8 of the coaxial cable 6.
ここで、 ミアンダ部 2、 幅広部 3の形状や範囲は、 第 1図 （b ) に示すように 、 ミアンダ部 2を三角形に形成し、 幅広部 3をミアンダ部 2側 （図中下側） まで 延長したものであってもよい。 また、 第 1図 （c ) に示すように、 ミアンダ部 2 を図中上側まで延長したものであってもよい。 さらにその他の形状や範囲であつ てもよく、 アンテナの共振周波数や必要な帯域によって適宜決定すればよい。 第 2図 （a ) および第 2図 （b ) は、 この発明の別の実施の形態であるループ アンテナの構成を示す図である。 第 2図 （a ) および第 2図 （b ) において、 放 射導体 1は、 L字型 （第 2図 （a ) ) や、 コの字型 （第 2図 （b ) ) のように 3 次元に形成されている。 このため、 部品 2 2との干渉を回避して、 ループアンテ ナ 3 0を効率的に配置することができる。 なお、 第 2図 （a ) およぴ第 2図 （b ) において、 第 1図に共通する部分については、 第 1図と同じ符号を付している 第 3図は、 この発明のさらに別の実施の形態であるループアンテナの構成を示 す図である。 第 3図 （a ) において、 放射導体 1は、 板状の誘電体 9の一面上に 形成されている。 これによつて、 誘電体 9の波長短縮効果により、 所定の共振周 波数に対して放射導体 1の長さを、 より短くする形成できるとともに、 強度を確 保することができる。 Here, as shown in FIG. 1 (b), the shape and range of the meander portion 2 and the wide portion 3 are such that the meander portion 2 is formed in a triangular shape, and the wide portion 3 is located on the meander portion 2 side (lower side in the figure). It may be extended. Further, as shown in FIG. 1 (c), the meander portion 2 may be extended to the upper side in the figure. Furthermore, other shapes and ranges may be used, and may be appropriately determined depending on the resonance frequency of the antenna and the required band. FIGS. 2 (a) and 2 (b) are diagrams showing a configuration of a loop antenna according to another embodiment of the present invention. In FIGS. 2 (a) and 2 (b), the radiating conductor 1 has an L-shape (FIG. 2 (a)) or a U-shape (FIG. 2 (b)). It is formed in a dimension. Therefore, interference with the component 22 can be avoided, and the loop antenna 30 can be arranged efficiently. In FIGS. 2 (a) and 2 (b), parts common to FIG. 1 are denoted by the same reference numerals as in FIG. 1, and FIG. FIG. 3 is a diagram showing a configuration of a loop antenna according to the embodiment of the present invention. In FIG. 3A, the radiating conductor 1 is formed on one surface of a plate-shaped dielectric 9. As a result, a predetermined resonance frequency is obtained due to the wavelength shortening effect of the dielectric 9. The length of the radiation conductor 1 can be made shorter with respect to the wave number, and the strength can be ensured.
また、 第 3図 （b ) においては、 誘電体 9を L字型に形成し、 誘電体 9の 2面 に放射導体 1を形成し、 これによつて部品 2 2などの干渉を避け、 ループアンテ ナ 3 0を効率的に配置することができる。  In addition, in FIG. 3 (b), the dielectric 9 is formed in an L shape, and the radiation conductor 1 is formed on two surfaces of the dielectric 9, thereby avoiding interference of the components 22 and the like, and forming a loop. The antenna 30 can be efficiently arranged.
さらに、 第 3図 （c ) に示すように、 誘電体 9を矩形状に形成し、 その複数面 に放射導体 1を形成する場合には、 誘電体 9の体積が大きいため、 波長短縮効果 を高めることができるとともに、 ループアンテナ 3 0をコンパクトに構成するこ とができる。 なお、 第 3図においても、 第 1図と共通する部分については、 第 1 図と同一の符号を付している。  Furthermore, as shown in FIG. 3 (c), when the dielectric 9 is formed in a rectangular shape and the radiation conductor 1 is formed on a plurality of surfaces, the volume of the dielectric 9 is large, so that the wavelength shortening effect is reduced. As a result, the loop antenna 30 can be made compact. In FIG. 3, parts common to FIG. 1 are denoted by the same reference numerals as in FIG.
第 4図は、 この発明のさらに別の実施の形態を示している。 第 4図 （a ) は、 ループアンテナ 3 0の表面を示す斜視図であり、 第 4図 （b ) は、 ループアンテ ナ 3 0の裏面を示す斜視図である。 第 4図 （a ) および第 4図 （b ) において、 誘電体 9は、 板状に形成され、 その一方の面 （表面） にば、 放射導体 1のミアン ダ部 2， 給電端子 4， および接地端子 5が設けられ、 他方の面 （裏面） には、 幅 広部 3が設けられている。 ミアンダ部 2と幅広部 3は、 誘電体 9の側面に設けら れた導体接続部 1 0によって接続され、 ループを形成している。 このように、 誘 電体 9上に放射導体 1を効率的に配置するとともに、 ミアンダ部 2同士が近接す るのを避け、 アンテナ特性の悪ィ匕を回避している。  FIG. 4 shows still another embodiment of the present invention. FIG. 4 (a) is a perspective view showing the front surface of the loop antenna 30, and FIG. 4 (b) is a perspective view showing the back surface of the loop antenna 30. In FIGS. 4 (a) and 4 (b), the dielectric 9 is formed in a plate shape, and on one surface (surface), the meander portion 2, the power supply terminal 4, and the A ground terminal 5 is provided, and a wide portion 3 is provided on the other surface (back surface). The meander portion 2 and the wide portion 3 are connected by a conductor connecting portion 10 provided on a side surface of the dielectric 9 to form a loop. As described above, the radiation conductor 1 is efficiently arranged on the dielectric 9, the meander portions 2 are prevented from approaching each other, and the antenna characteristics are not deteriorated.
第 5図は、 この発明のさらに別の実施の形態を示している。 第 5図において、 放射導体 1は、 誘電体 9に覆われており、 誘電体 9から給電端子 4と接地端子 5 とが露出している。 このように、 放射導体 1を誘電体 9で覆うことによって、 誘 電体 9の波長短縮効果を高めるとともに、 放射導体 1を外傷や酸化から保護する ことができる。  FIG. 5 shows still another embodiment of the present invention. In FIG. 5, the radiation conductor 1 is covered with a dielectric 9, and the feed terminal 4 and the ground terminal 5 are exposed from the dielectric 9. Thus, by covering the radiation conductor 1 with the dielectric 9, the wavelength shortening effect of the dielectric 9 can be enhanced, and the radiation conductor 1 can be protected from external damage and oxidation.
第 6図は、 この発明のさらに別の実施の形態を示す図である。 第 6図において 、 1 1は、 汎用のモノポール型チップアンテナであり、 誘電体 1 7にミアンダ状 の放射導体 1 2が形成され、 端子 1 3， 1 5を有する。 一方、 基板 1 8には、 幅 広部 3と、 給電端子 4、 接地端子 5、 端子接続部 14， 16が形成されている。 ここで、 チップアンテナ 1 1の端子 13， 15を、 基板 18上の端子接続部 14 , 16にそれぞれ対応させて実装すると、 給電端子 4一 1幅広部 3—端子接続部 1 4一端子 13一放射導体 12—端子 15—端子接続部 16—幅広部 3—接地端子 5に至るループが形成され、 ループアンテナとして動作が可能となる。 このよう 'に、 汎用品であるチップアンテナを有効に活用してこの発明にかかるループアン テナを得ることも可能である。 FIG. 6 is a diagram showing still another embodiment of the present invention. In FIG. 6, reference numeral 11 denotes a general-purpose monopole chip antenna, in which a meandering radiation conductor 12 is formed on a dielectric 17 and terminals 13 and 15 are provided. On the other hand, substrate 18 has a width The wide part 3, the power supply terminal 4, the ground terminal 5, and the terminal connection parts 14 and 16 are formed. Here, when the terminals 13 and 15 of the chip antenna 11 are mounted so as to correspond to the terminal connection portions 14 and 16 on the board 18, respectively, the power supply terminal 4 1 1 the wide portion 3—the terminal connection portion 1 4 1 terminal 13 1 A loop leading to the radiation conductor 12—terminal 15—terminal connection part 16—wide part 3—ground terminal 5 is formed, enabling operation as a loop antenna. In this way, it is possible to obtain a loop antenna according to the present invention by effectively utilizing a general-purpose chip antenna.
第 7図は、 この発明にかかるループアンテナを携帯電話に搭載した状態を示す 斜視図である。 第 7図 （a) に示す携帯電話 20の頂部や第 7図 （b) に示す携 帯電話 20の側部など、 ノレ一プアンテナ 30は、 携帯電話 20の筐体と基板 21 とのわずかな隙間に搭載可能であり、 携帯電話の小型化、 突起を排したことによ る使い勝手の向上、 意匠性の向上に資することができる。  FIG. 7 is a perspective view showing a state where the loop antenna according to the present invention is mounted on a mobile phone. 7 (a) and the side of the mobile phone 20 shown in FIG. 7 (b), the no-repeat antenna 30 has a slight difference between the housing of the mobile phone 20 and the substrate 21. It can be mounted in gaps, which contributes to the downsizing of mobile phones, improved usability by eliminating protrusions, and improved design.
(実施例）  (Example)
この発明の実施例として、 第 8図 （a) 乃至第 8図 （e) に示すループアンテ ナを作成し、 その特性を測定した。 すなわち、 長さ 28mm、 幅 10 mm、 厚さ 1. 6 mm、 誘電率 3. 9の基板上に厚さ 70 μ mの銅箔によって表面に導体太 さ 0. 8mm、 ミアンダ間隔 1. 0 mm (両端のみ 1. 1mm) のミアンダを形 成し、 裏面全体に前記銅箔を張り、 幅広部とし、 誘電体側面に幅 lmmの導体接 続部を設けた。 なお、 第 8図 （a) は平面図であり、 第 8図 （b) は右側面図で あり、，第 8図 （c) は正面図であり、 第 8図 （d) は裏面図であり、 第 8図 （e ) は背面図である。 'このノレープアンテナを幅 40mm、 長さ 110mmの有限地 板に対し、 第 7図 （a) のように配置した場合の反射特性を、 ネットワークアナ ライザで測定した VSWRおよぴスミスチャートを第 9図 （a) およぴ第 9図 （ b) に示す。 なお、 第 9図 （a) は VSWRチャートであり、 第 9図 （b) はス ミスチヤ一トである。  As an example of the present invention, loop antennas shown in FIGS. 8 (a) to 8 (e) were prepared and their characteristics were measured. In other words, a conductor thickness of 0.8 mm and a meander spacing of 1.0 mm are formed on the surface of a 70 μm thick copper foil on a substrate with a length of 28 mm, a width of 10 mm, a thickness of 1.6 mm, and a dielectric constant of 3.9. A meander (only 1.1 mm at both ends) was formed, the copper foil was applied to the entire back surface to make a wide portion, and a conductor connection portion having a width of lmm was provided on the dielectric side surface. 8 (a) is a plan view, FIG. 8 (b) is a right side view, FIG. 8 (c) is a front view, and FIG. 8 (d) is a back view. Yes, Fig. 8 (e) is a rear view. VSWR and Smith charts measured by a network analyzer are shown in Fig. 7 (a) for the reflection characteristics when this norepe antenna is placed as shown in Fig. 7 (a) on a finite ground plane of 40mm width and 110mm length. Figures 9 (a) and 9 (b) are shown. Fig. 9 (a) is the VSWR chart, and Fig. 9 (b) is the Smith chart.
また、 送信側にダイポールアンテナを置き、 受信側に回転可能な台にとりつけ たこの発明のアンテナを置いて電波暗室内で測定した周波数 920MHzの放射 パターンを第 10図 （a) 〜第 10図 （c) に示し、 周波数 1795MHzの放 射パターンを第 11図 （a) 〜第 10図 （c) に示す。 なお、 第 10図 （a) お よび第 11図 （a) は、 xy面内指向性を示し、 第 10図 （b) およぴ第 1 1図 (b) は、 y z面内指向性を示し、 第 10図 （c) および第 11図 （c) は、 z X面內指向性を示す。 In addition, a dipole antenna was placed on the transmitting side, and the antenna of the present invention mounted on a rotatable table was placed on the receiving side. The patterns are shown in Figs. 10 (a) to 10 (c), and the emission patterns at a frequency of 1795MHz are shown in Figs. 11 (a) to 10 (c). 10 (a) and 11 (a) show the directivity in the xy plane, and FIGS. 10 (b) and 11 (b) show the directivity in the yz plane. FIG. 10 (c) and FIG. 11 (c) show the z X-plane 內 directivity.
このように、 この実施例においてその特性が、 周波数 880〜96 OMH zお ょぴ 1710〜： 1880MHzで、 VSWRが 3以下、 最大利得 + 1. 85 dB i (920 MH z送受信時） 、 +0. 55 dB i (1795 MH z送受信時） 、 放射効率 56 % (920MHz送受信時） 、 51 % (1795MHz送受信時） のアンテナを長さ 28mmX幅 1 OmmX厚さ 1. 6 mmの寸法で実現すること ができた。  Thus, in this embodiment, the characteristics are as follows: the frequency is 880 to 96 OMHz, and the frequency is 1710 to: 1880 MHz, the VSWR is 3 or less, the maximum gain is +1.85 dBi (when transmitting and receiving at 920 MHz), An antenna with 55 dBi (1795 MHz transmission / reception), radiation efficiency 56% (920 MHz transmission / reception), 51% (1795 MHz transmission / reception) with dimensions of 28 mm long x 1 Omm x 1.6 mm thick Was completed.
この発明によれば、 上述したように、 優れた特性で極めて小型のアンテナを提 供することができる。 産業上の利用可能性  According to the present invention, as described above, an extremely small antenna with excellent characteristics can be provided. Industrial applicability
以上のように、 この発明では、 実用上満足できる帯域を確保しつつ、 更なる小 型化を図ったループアンテナを実現できるので、 携帯電話、 携帯端末などに好適 である。  As described above, according to the present invention, it is possible to realize a further miniaturized loop antenna while securing a practically satisfactory band, and it is suitable for a mobile phone, a mobile terminal, and the like.

Claims

請 求 の 範 囲 The scope of the claims
1 . 放射導体をループ状に形成し、 一端側に給電し、 他端側を接地導体に接続 したループアンテナにおいて、 ループ状の放射導体の一部をミアンダ状に形成し たミアンダ部を備えたことを特徴とするループアンテナ。 1. A loop antenna in which a radiating conductor is formed in a loop shape, one end is fed, and the other end is connected to a ground conductor, and a meander portion in which a part of the loop radiating conductor is formed in a meander shape is provided. A loop antenna, characterized in that:
2 . 前記放射導体が三次元に形成されたことを特徴とする請求の範囲第 1項に 記載のループアンテナ。 2. The loop antenna according to claim 1, wherein the radiation conductor is formed three-dimensionally.
3 . 前記放射導体が誘電体上に形成されたことを特徴とする請求の範囲第 1項 に記載のルー： 3. The loop according to claim 1, wherein the radiation conductor is formed on a dielectric.
4 . 前記放射導体が誘電体の複数面上に分割して形成されたことを特徴とする 請求の範囲第 1項に記載のルー： 4. The loop according to claim 1, wherein the radiation conductor is formed by being divided on a plurality of surfaces of a dielectric.
5 . 前記ミアンダ部を板状誘電体の一面側に形成し、 該ミアンダ部以外のルー プ状の放射導体を前記板状誘電体の裏側に位置する他の面に形成したことを特徴 とする請求の範囲第 1項に記載のループアンテナ。 5. The meander portion is formed on one surface of the plate-shaped dielectric, and a loop-shaped radiating conductor other than the meander portion is formed on another surface located on the back side of the plate-shaped dielectric. The loop antenna according to claim 1.
6 . 前記放射導体上にさらに誘電体を配置したことを特徴とする請求の範囲第 1項に記載のルー： 6. The loop according to claim 1, wherein a dielectric is further disposed on the radiation conductor.
7 . 前記放射導体の一部を基板上に形成し、 前記放射導体の残りの一部を別体 に形成し、 前記別体に形成した放射導体の一部を前記基板に載置することによつ て所望の放射導体を形成することを特徴とする請求の範囲第 1項に記載のループ 7. A part of the radiation conductor is formed on a substrate, a part of the remaining radiation conductor is formed separately, and a part of the radiation conductor formed separately is placed on the substrate. The loop according to claim 1, wherein a desired radiation conductor is formed.
8 . 放射導体をループ状に形成し、 一端側に給電し、 他端側を接地導体に接続 したループアンテナにおいて、 ループ状の放射導体の一部をミアンダ状に形成し たミアンダ部と、 他の一部を幅広に形成した幅広部とを備えたことを特徴とする ル- ― 8. In a loop antenna in which the radiation conductor is formed in a loop shape, one end is fed, and the other end is connected to a ground conductor, a meander portion in which a part of the loop radiation conductor is formed in a meander shape, Characterized by having a wide part in which a part of the part is formed wide.
9 . 前記放射導体が三次元に形成されたことを特徴とする請求の範囲第 8項に 記載のルー： 9. The loop according to claim 8, wherein the radiation conductor is formed three-dimensionally.
1 0 . 前記放射導体が誘電体上に形成されたことを特徴とする請求の範囲第 8 項に記載のルー：  10. The loop according to claim 8, wherein the radiation conductor is formed on a dielectric.
1 1 . 前記放射導体が誘電体の複数面上に分割して形成されたことを特徴とす る請求の範囲第 8項に記載のループアンテナ。 11. The loop antenna according to claim 8, wherein the radiation conductor is formed by being divided on a plurality of surfaces of a dielectric.
1 2 . 前記ミアンダ部を板状誘電体の一面側に形成し、 前記幅広部を前記板状 誘電体の裏側に位置する他の面に形成したことを特徴とする請求の範囲第 8項に 記載のループアンテナ。 12. The claim 8, wherein the meander portion is formed on one surface side of the plate-shaped dielectric, and the wide portion is formed on another surface located on the back side of the plate-shaped dielectric. The described loop antenna.
1 3 . '前記放射導体上にさらに誘電体を配置したことを特徴とする請求の範囲 第 8項に記載のループアンテナ。 13. The loop antenna according to claim 8, wherein a dielectric is further disposed on the radiation conductor.
1 4 . 前記放射導体の一部を基板上に形成し、 前記放射導体の残りの一部を別 体に形成し、 前記別体に形成した放射導体の一部を前記基板に載置することによ つて所望の放射導体を形成することを特徴とする請求の範囲第 8項に記載のルー  14. Forming a part of the radiation conductor on a substrate, forming the remaining part of the radiation conductor separately, and placing a part of the radiation conductor formed separately on the substrate. 9. The loop according to claim 8, wherein a desired radiation conductor is formed by
PCT/JP2003/011774 2002-09-13 2003-09-16 Loop antenna WO2004025781A1 (en)

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