JPH08195609A - Portable radio equipment incorporated type inverted f antenna - Google Patents
Portable radio equipment incorporated type inverted f antennaInfo
- Publication number
- JPH08195609A JPH08195609A JP7022388A JP2238895A JPH08195609A JP H08195609 A JPH08195609 A JP H08195609A JP 7022388 A JP7022388 A JP 7022388A JP 2238895 A JP2238895 A JP 2238895A JP H08195609 A JPH08195609 A JP H08195609A
- Authority
- JP
- Japan
- Prior art keywords
- antenna
- human body
- portable radio
- radio equipment
- parasitic element
- Prior art date
- Legal status (The legal status 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 status listed.)
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- Support Of Aerials (AREA)
- Transceivers (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、携帯無線機に内蔵する
逆Ｆアンテナに関し、特に、小型化を可能にしたもので
ある。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an inverted F antenna incorporated in a portable wireless device, and more particularly, it can be made compact.
【０００２】[0002]
【従来の技術】従来の移動電話機などの携帯無線機に
は、逆Ｆアンテナと呼ばれる板状の導体を放射素子とす
るアンテナが内蔵アンテナとして利用されている。この
逆Ｆアンテナは、図５に示すように、周囲の長さが約λ
／２（λは使用周波数の波長）であるアンテナ導体板１
と、携帯無線機に組込んだときにシールドケースを構成
するグランド導体板２と、アンテナ導体板１とグランド
導体板２とを接続する短絡板３と、アンテナ導体板１に
給電する同軸線路の給電線４とを備えている。2. Description of the Related Art In a conventional portable radio device such as a mobile phone, an antenna called a reverse F antenna having a plate-shaped conductor as a radiation element is used as a built-in antenna. As shown in FIG. 5, this inverted F antenna has a perimeter of about λ.
/ 2 (λ is the wavelength of the used frequency) Antenna conductor plate 1
A ground conductor plate 2 that constitutes a shield case when incorporated in a portable wireless device, a short-circuit plate 3 that connects the antenna conductor plate 1 and the ground conductor plate 2, and a coaxial line that supplies power to the antenna conductor plate 1. And a power supply line 4.
【０００３】このアンテナは、給電線から給電された無
線機出力をアンテナ導体板１を通して放射し、また、受
信電波をアンテナ導体板１で集めて無線機に導いてい
る。このアンテナのＶＳＷＲ（電圧定在波比）≦２とな
る比帯域幅は約６％である。This antenna radiates an output of a radio device fed from a feeder line through an antenna conductor plate 1 and collects received radio waves with the antenna conductor plate 1 to guide the radio wave to the radio device. The ratio bandwidth of VSWR (voltage standing wave ratio) ≦ 2 of this antenna is about 6%.
【０００４】しかし、この帯域幅は、アンテナを携帯無
線機に内蔵すると、周囲部品の影響で狭くなり、また、
アンテナの共振周波数が変動する。However, when the antenna is built into the portable radio, this bandwidth becomes narrow due to the influence of surrounding parts, and
The resonance frequency of the antenna fluctuates.
【０００５】このアンテナを、より広帯域の特性を持つ
ように改良したものが図６に示す逆Ｆアンテナである。
図６（ａ）はその斜視図を示し、図６（ｂ）は側面図を
示している。このアンテナは、アンテナ導体板１とグラ
ンド導体板２との間に整合板５を配置し、この整合板５
に給電線４で給電している。An inverse F antenna shown in FIG. 6 is obtained by improving this antenna so as to have a wider band characteristic.
FIG. 6A shows a perspective view thereof, and FIG. 6B shows a side view thereof. In this antenna, a matching plate 5 is arranged between the antenna conductor plate 1 and the ground conductor plate 2, and the matching plate 5
Is fed to the power feeding line 4.
【０００６】このアンテナでは、整合板５がアンテナ導
体板１とグランド導体板２との間で複共振を起こし、そ
れがアンテナの広帯域化をもたらす（参考文献：石曾根
孝之、関根秀一、石川斉、西田茂穂，”整合板を付けた
逆Ｆアンテナのインピーダンス特性”，昭和６１年度電
子通信学会総合全国大会、ｐｐ．３−１１２）。In this antenna, the matching plate 5 causes multiple resonances between the antenna conductor plate 1 and the ground conductor plate 2, which causes the antenna to have a wide band (reference: Takayuki Ishisone, Shuichi Sekine, Hitoshi Ishikawa, Shigeho Nishida, "Impedance Characteristics of Inverted-F Antenna with Matching Plate," 1986 IEICE General Conference, pp. 3-112).
【０００７】[0007]
【発明が解決しようとする課題】しかし、図６に示す、
整合板を備えた逆Ｆアンテナは、広帯域特性を備えてい
るものの、構造が複雑で、整合板とアンテナ導体板との
固定方法が困難であるという問題点を有している。However, as shown in FIG.
Although the inverted F antenna provided with the matching plate has wide band characteristics, it has a problem that the structure is complicated and the fixing method between the matching plate and the antenna conductor plate is difficult.
【０００８】また、携帯無線機は、人体の近くで使用さ
れるため、電波の放射特性が人体の影響を受けて変化し
たり、また、人体が携帯無線機の電波を浴びて（ハザー
ト）身体的影響を受けるなどの問題がある。そのため電
波の放射方向と人体の位置との関係に配慮することが求
められている。Further, since the portable wireless device is used near the human body, the radiation characteristics of the radio waves change under the influence of the human body, and the human body is exposed to the radio waves of the portable wireless device (hazard). There is a problem such as being affected by the impact Therefore, it is required to consider the relationship between the radiation direction of radio waves and the position of the human body.
【０００９】本発明は、こうした従来の課題を解決する
ものであり、広帯域特性を有し、受信感度が高く、小型
化することが可能であり、また、人体の影響を受けた
り、人体に影響を及ぼしたりしないような形で電波を放
射することができる携帯無線機内蔵逆Ｆアンテナを提供
することを目的としている。The present invention solves these conventional problems, has wide band characteristics, high reception sensitivity, and can be miniaturized. Further, the present invention is affected by the human body and affects the human body. It is an object of the present invention to provide an inverted F antenna with a built-in portable wireless device that can radiate radio waves in a form that does not affect the frequency.
【００１０】[0010]
【課題を解決するための手段】そこで、本発明では、平
行する二つの導体板を備えた携帯無線機内蔵逆Ｆアンテ
ナにおいて、この二つの導体板と平行する携帯無線機の
樹脂ケース面に金属層を形成して無給電導体素子として
いる。In view of the above, according to the present invention, in an inverted F antenna with a built-in portable wireless device having two parallel conductor plates, a metal is provided on the resin case surface of the portable wireless device parallel to the two conductor plates. Layers are formed to serve as parasitic conductor elements.
【００１１】また、この金属層を蒸着により形成してい
る。The metal layer is formed by vapor deposition.
【００１２】また、携帯無線機を操作する人体の方向に
放射パターンの指向性が向かないように、この無給電導
体素子を携帯無線機内に位置させている。Further, the parasitic conductor element is located inside the portable radio so that the radiation pattern does not have directivity toward the human body operating the portable radio.
【００１３】[0013]
【作用】そのため、携帯無線機樹脂ケースに蒸着で形成
した無給電素子がアンテナの複共振を誘起し、広い帯域
幅でＶＳＷＲの値が低下する。従って、アンテナの構成
を小型化しても充分なアンテナ特性を確保することが可
能になる。Therefore, the parasitic element formed by vapor deposition on the resin case of the portable wireless device induces the multiple resonance of the antenna, and the value of VSWR is lowered in a wide bandwidth. Therefore, it is possible to secure sufficient antenna characteristics even if the configuration of the antenna is reduced.
【００１４】また、アンテナからの電波の放射は無給電
素子の方向に指向性を持つ。従って、このアンテナを携
帯無線機に組込むとき、この無給電素子が携帯無線機を
操作する人体の反対側に位置するように配置した場合に
は、人体による悪影響を受けずに、大きい強度の電波放
射を行なうことができ、また、アンテナによる人体のハ
ザートを防ぐことができる。Further, radiation of radio waves from the antenna has directivity in the direction of the parasitic element. Therefore, when this antenna is installed in a portable wireless device, if the parasitic element is placed on the opposite side of the human body operating the portable wireless device, radio waves of high intensity will not be adversely affected by the human body. Radiation can be performed, and the hazard of the human body due to the antenna can be prevented.
【００１５】[0015]
【実施例】本発明の実施例における携帯無線機内蔵逆Ｆ
アンテナは、図１に示すように、従来の逆Ｆアンテナの
構成、即ち、アンテナ導体板１と、携帯無線機のシール
ドケースとして機能するグランド導体板２と、アンテナ
導体板１及びグランド導体板２を接続する短絡板３と、
アンテナ導体板１に給電する給電線４とから成る構成の
外に、携帯無線機の樹脂ケース６に金属を蒸着して形成
した無給電素子７を備えている。[Embodiment] Reverse F with a built-in portable radio in an embodiment of the present invention
As shown in FIG. 1, the antenna has a configuration of a conventional inverted F antenna, that is, an antenna conductor plate 1, a ground conductor plate 2 that functions as a shield case of a portable wireless device, an antenna conductor plate 1 and a ground conductor plate 2. Short-circuit plate 3 for connecting
In addition to the configuration including the power supply line 4 that supplies power to the antenna conductor plate 1, a parasitic element 7 formed by depositing metal on a resin case 6 of the portable wireless device is provided.
【００１６】この樹脂ケース６は、逆Ｆアンテナのアン
テナ導体板１を収容できる大きさの空間を持つ無蓋筐体
８を一体的に備えており、この筐体８の底面に無給電素
子７の金属層を蒸着で形成している。樹脂ケース６とグ
ランド導体板２とを重ね合わせて、アンテナ導体板１を
筐体８に収容したとき、この無給電素子７は、アンテナ
導体板１と一定距離を隔てて平行する。The resin case 6 is integrally provided with an open casing 8 having a space large enough to accommodate the antenna conductor plate 1 of the inverted F antenna, and the parasitic element 7 is provided on the bottom surface of the casing 8. The metal layer is formed by vapor deposition. When the resin case 6 and the ground conductor plate 2 are overlapped and the antenna conductor plate 1 is housed in the housing 8, the parasitic element 7 is parallel to the antenna conductor plate 1 with a certain distance.
【００１７】この樹脂ケース６は、アンテナのグランド
導体板２と重ね合わせて、アンテナ導体板１を筐体８に
収容した状態で、図２に示すように、操作ボタンやレシ
ーバ10を備える携帯無線機表側の樹脂ケース９と、バッ
テリー11と組み合わされ、アンテナを内蔵する携帯無線
機が構成される。The resin case 6 is superposed on the ground conductor plate 2 of the antenna, and the antenna conductor plate 1 is housed in the housing 8 as shown in FIG. By combining the resin case 9 on the front side of the machine and the battery 11, a portable radio having an antenna is built.
【００１８】このアンテナのアンテナ導体板１、グラン
ド導体板２、短絡板３及び給電線４は典型的な逆Ｆアン
テナを形成している。樹脂ケース６に蒸着で形成した無
給電素子７は、このアンテナとカップリングして複共振
し、アンテナの特性を広帯域化する働きをする。また、
このアンテナからの放射は、無給電素子７の方向に大き
く放射され、無給電素子７の側に指向性を示す。The antenna conductor plate 1, the ground conductor plate 2, the short-circuit plate 3 and the feed line 4 of this antenna form a typical inverted F antenna. The parasitic element 7 formed on the resin case 6 by vapor deposition is coupled to this antenna to cause multiple resonance, and serves to broaden the characteristics of the antenna. Also,
Radiation from this antenna is largely radiated in the direction of the parasitic element 7, and exhibits directivity on the side of the parasitic element 7.
【００１９】図３には、無給電素子を持つ実施例のアン
テナと、無給電素子を持たない従来のアンテナとのＶＳ
ＷＲ特性を比較して示している。これらのアンテナは、
いずれも１．５ＧＨｚ帯で共振しているが、無給電素子
を持つ実施例のアンテナの方が１に近いＶＳＷＲの値を
示し、ＶＳＷＲ≦２となる比帯域幅は約１０％に及んで
いる。In FIG. 3, VS of an antenna of the embodiment having a parasitic element and a conventional antenna having no parasitic element
The WR characteristics are shown for comparison. These antennas are
Both of them resonate in the 1.5 GHz band, but the antenna of the embodiment having the parasitic element shows a value of VSWR closer to 1, and the specific bandwidth for VSWR ≦ 2 reaches about 10%. .
【００２０】また、図４は、無給電素子を持つ実施例の
アンテナと、無給電素子を持たない従来のアンテナとの
水平面（ＺＸ面）における放射パターンを比較して示し
ている。無給電素子を持つアンテナは、無給電素子のあ
る方向（０°の方向）に大きく放射されることが明らか
である。FIG. 4 shows a comparison of the radiation patterns on the horizontal plane (ZX plane) between the antenna of the embodiment having a parasitic element and the conventional antenna having no parasitic element. It is clear that an antenna having a parasitic element is largely radiated in a certain direction (0 ° direction) of the parasitic element.
【００２１】このアンテナの共振周波数、帯域幅、放射
パターンは、無給電素子の大きさ、または配置位置を変
えることにより、調整することができる。The resonance frequency, bandwidth, and radiation pattern of this antenna can be adjusted by changing the size or position of the parasitic element.
【００２２】このように実施例の携帯無線機内蔵逆Ｆア
ンテナは、帯域幅が広く、また、共振周波数におけるＶ
ＳＷＲが低い。そのため、アンテナを小型化しても充分
なアンテナ特性を確保することができる。As described above, the inverted F antenna with a built-in portable radio of the embodiment has a wide bandwidth and V at the resonance frequency.
SWR is low. Therefore, sufficient antenna characteristics can be secured even if the antenna is downsized.
【００２３】また、このアンテナは、無給電素子の方向
に指向性を持つので、携帯無線機に内蔵したアンテナの
無給電素子を、携帯無線機を操作する人体と反対側に位
置させることにより、人体の影響を受けずに、大きな放
射を行なうことが可能になる。また、この場合、アンテ
ナから放射された電波の人体に対するハザートを防ぐこ
とができる。Further, since this antenna has directivity in the direction of the parasitic element, by locating the parasitic element of the antenna incorporated in the portable wireless device on the side opposite to the human body operating the portable wireless device, It becomes possible to emit a large amount of radiation without being affected by the human body. Further, in this case, it is possible to prevent the hazard of the radio wave radiated from the antenna with respect to the human body.
【００２４】この無給電素子は、給電されていないの
で、給電線との接続や固定などが一切必要ない。そのた
めアンテナの構成が極めて簡単である。Since this parasitic element is not supplied with power, it does not need to be connected or fixed to a power supply line. Therefore, the configuration of the antenna is extremely simple.
【００２５】なお、このアンテナを携帯無線機に組込む
ときの構成は、図２に示した例以外に、アンテナ導体板
１を携帯無線機の側方向に向けるなど、種々の構成を取
ることができる。The structure for incorporating the antenna into the portable wireless device may be various other than the example shown in FIG. 2 such that the antenna conductor plate 1 is directed to the side of the portable wireless device. .
【００２６】また、無給電素子は、蒸着以外の方法で被
膜状に形成しても良い。The parasitic element may be formed into a film by a method other than vapor deposition.
【００２７】[0027]
【発明の効果】以上の実施例の説明から明らかなよう
に、本発明の携帯無線機内蔵逆Ｆアンテナは、構成が簡
単で、且つ、帯域幅が広く、共振周波数でのＶＳＷＲ値
が低いという特性を持つ。そのため、アンテナの小型化
を図ることができる。As is apparent from the above description of the embodiments, the portable radio device built-in inverted F antenna of the present invention has a simple structure, a wide bandwidth, and a low VSWR value at the resonance frequency. It has characteristics. Therefore, the size of the antenna can be reduced.
【００２８】また、その指向性を利用して、人体による
アンテナ特性への悪影響、または、アンテナによる人体
のハザートを防ぐことができる。Further, by utilizing the directivity, it is possible to prevent the antenna characteristics from being adversely affected by the human body or the hazard of the human body due to the antenna.
【図１】本発明の実施例における携帯無線機内蔵逆Ｆア
ンテナの構成を示す斜視図、FIG. 1 is a perspective view showing a configuration of an inverted F antenna with a built-in portable wireless device according to an embodiment of the present invention,
【図２】実施例のアンテナを内蔵する携帯無線機の外観
図、FIG. 2 is an external view of a portable wireless device including the antenna of the embodiment,
【図３】実施例のアンテナ及び従来のアンテナのＶＳＷ
Ｒ特性を示す特性図、FIG. 3 is a VSW of an antenna of an example and a conventional antenna.
A characteristic diagram showing R characteristics,
【図４】実施例のアンテナ及び従来のアンテナの放射パ
ターン図、FIG. 4 is a radiation pattern diagram of an antenna of an example and a conventional antenna,
【図５】従来の携帯無線機内蔵逆Ｆアンテナの構成を示
す斜視図、FIG. 5 is a perspective view showing a configuration of a conventional inverted F antenna with a built-in portable wireless device,
【図６】従来の別の携帯無線機内蔵逆Ｆアンテナの構成
を示す斜視図(ａ)と断面図(ｂ)である。FIG. 6 is a perspective view (a) and a sectional view (b) showing the configuration of another conventional inverted F antenna with a built-in portable wireless device.
１ アンテナ導体板 ２ グランド導体板 ３ 短絡板 ４ 給電線 ５ 整合板 ６ 携帯無線機の樹脂ケース ７ 無給電導体素子 ８ 筐体 ９ 携帯無線機表面の樹脂ケース 10 レシーバー 11 バッテリー 1 antenna conductor plate 2 ground conductor plate 3 short-circuit plate 4 feeding line 5 matching plate 6 resin case for mobile radio 7 parasitic conductor element 8 housing 9 resin case on the surface of mobile radio 10 receiver 11 battery
Claims (3)
機内蔵逆Ｆアンテナにおいて、前記二つの導体板と平行
する携帯無線機の樹脂ケース面に金属層を形成して無給
電導体素子としたことを特徴とする携帯無線機内蔵逆Ｆ
アンテナ。1. An inverted-F antenna with a built-in portable radio device, comprising two parallel conductor plates, wherein a metal layer is formed on a resin case surface of the portable radio device parallel to the two conductor plates to form a parasitic conductor element. Reverse F with built-in portable radio
antenna.
を特徴とする請求項１に記載の携帯無線機内蔵逆Ｆアン
テナ。2. The inverted F antenna with a built-in portable wireless device according to claim 1, wherein the metal layer is formed by vapor deposition.
放射パターンの指向性が向かないように、前記無給電導
体素子を前記携帯無線機内に位置させることを特徴とす
る請求項１または２に記載の携帯無線機内蔵逆Ｆアンテ
ナ。3. The parasitic conductor element is located inside the portable wireless device so that the radiation pattern does not have directivity in the direction of the human body operating the portable wireless device. An inverted F antenna with a built-in portable wireless device described in.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7022388A JPH08195609A (en) | 1995-01-18 | 1995-01-18 | Portable radio equipment incorporated type inverted f antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP7022388A JPH08195609A (en) | 1995-01-18 | 1995-01-18 | Portable radio equipment incorporated type inverted f antenna |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH08195609A true JPH08195609A (en) | 1996-07-30 |
Family
ID=12081279
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP7022388A Pending JPH08195609A (en) | 1995-01-18 | 1995-01-18 | Portable radio equipment incorporated type inverted f antenna |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH08195609A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003258538A (en) * | 2002-02-28 | 2003-09-12 | Fec Inc | Patch antenna for wearable terminal, and antenna system for the wearable terminal employing the same |
| EP1394895A1 (en) * | 2002-09-02 | 2004-03-03 | Sony Ericsson Mobile Communications AB | Directive antenna elements |
| WO2004021511A3 (en) * | 2002-09-02 | 2004-05-06 | Sony Ericsson Mobile Comm Ab | Directive antenna elements |
| US6856819B2 (en) | 2000-03-07 | 2005-02-15 | Nec Corporation | Portable wireless unit |
| JP2006501699A (en) * | 2002-03-04 | 2006-01-12 | シーメンス インフォメイション アンド コミュニケイション モバイル エルエルシー | Broadband flat inverted F antenna |
| US7002521B2 (en) | 2002-02-27 | 2006-02-21 | Matsushita Electric Industrial Co., Ltd. | Antenna device for radio apparatus |
| JP2021129289A (en) * | 2020-02-12 | 2021-09-02 | 北京小米移動軟件有限公司Beijing Xiaomi Mobile Software Co., Ltd. | Terminal device |
-
1995
- 1995-01-18 JP JP7022388A patent/JPH08195609A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6856819B2 (en) | 2000-03-07 | 2005-02-15 | Nec Corporation | Portable wireless unit |
| US7002521B2 (en) | 2002-02-27 | 2006-02-21 | Matsushita Electric Industrial Co., Ltd. | Antenna device for radio apparatus |
| JP2003258538A (en) * | 2002-02-28 | 2003-09-12 | Fec Inc | Patch antenna for wearable terminal, and antenna system for the wearable terminal employing the same |
| JP2006501699A (en) * | 2002-03-04 | 2006-01-12 | シーメンス インフォメイション アンド コミュニケイション モバイル エルエルシー | Broadband flat inverted F antenna |
| EP1394895A1 (en) * | 2002-09-02 | 2004-03-03 | Sony Ericsson Mobile Communications AB | Directive antenna elements |
| WO2004021511A3 (en) * | 2002-09-02 | 2004-05-06 | Sony Ericsson Mobile Comm Ab | Directive antenna elements |
| JP2021129289A (en) * | 2020-02-12 | 2021-09-02 | 北京小米移動軟件有限公司Beijing Xiaomi Mobile Software Co., Ltd. | Terminal device |
| US11483421B2 (en) | 2020-02-12 | 2022-10-25 | Beijing Xiaomi Mobile Software Co., Ltd. | Terminal device |
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