JP4071554B2

JP4071554B2 - Antenna device

Info

Publication number: JP4071554B2
Application number: JP2002177277A
Authority: JP
Inventors: 伸明間嶋; 正史越; 友昭西木戸; 裕斎藤; 芳雄小柳
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2002-06-18
Filing date: 2002-06-18
Publication date: 2008-04-02
Anticipated expiration: 2022-06-18
Also published as: JP2004023546A

Description

【０００１】
【発明の属する技術分野】
本発明は、携帯電話機（以降、携帯電話と略称する）などの小型の無線機に内蔵されるアンテナ装置に関し、特に使用者が無線機を手で保持して内蔵アンテナに指が近接した場合におけるアンテナ装置の利得改善に関する。
【０００２】
【従来の技術】
従来、携帯電話用アンテナにおいて、外付けの伸縮アンテナと通話時に人体と反対側に配置される内蔵アンテナを用いてダイバーシチ受信を行う構成が広く採用されている。このような携帯電話が使用者の手で保持された通話状態において、一般に従来の内蔵アンテナは伸縮アンテナよりも手に近接する位置に配置される。そのため、従来の内蔵アンテナにおいては、指とアンテナとの間の電磁的な相互作用によりアンテナ性能が劣化しやすいという問題点があった。
【０００３】
この場合、通話状態における水平面パターン平均化利得（以下、ＰＡＧと記する）は、指がアンテナに近接しない場合のそれに比べて約７ｄＢ劣化する。この性能劣化の要因の一つは、指が近接することによる内蔵アンテナの共振周波数の変化によって引き起こされるインピーダンス不整合損失である。
【０００４】
この問題点を解決するものとして、例えば特開平２０００−１１４８５６号公報、または特開平１０−２２４１４２号公報で示されるような、逆Ｆアンテナの短絡素子をスイッチで切替えることにより共振周波数を変化させる構成が提案されている。
【０００５】
また特開平１０−１９０３４５号公報では、給電部に設けられた容量性リアクタンスを変化させることで共振周波数を変化させるものが示されている。また特開平１１−１４５８５２号公報では、整合回路を切替える手法を用いた構成が提案されている。
【０００６】
【発明が解決しようとする課題】
しかしながら、上記従来の内蔵アンテナでは、共振周波数の変化によるインピーダンス不整合損失を防止する効果があるが、指が近接することによる効率劣化を抑えることができない。その場合、通話状態におけるＰＡＧは、指がアンテナに近接しない場合のそれに比べて約５ｄＢ劣化するという課題があった。
【０００７】
本発明は、上記事情に鑑みてなされたもので、その目的は、携帯無線機等において指等がアンテナに近接した場合のＰＡＧを改善することができるアンテナ装置を提供することにある。
【０００８】
【課題を解決するための手段】
本発明のアンテナ装置は、板状逆Ｆアンテナを有するアンテナ装置であって、前記板状逆Ｆアンテナに複数箇所設けられた複数の給電部のいずれか一つを選択する給電部切替手段と、当該アンテナ装置に近接する指の位置を検出する位置検出手段と、前記検出された指の位置よって前記複数の給電部のいずれか一つを決定し、前記給電部切替手段により前記決定された給電部を選択する給電部決定手段と、を備えることを特徴とする。
【００１２】
また、本発明のアンテナ装置は、板状逆Ｆアンテナを有するアンテナ装置であって、前記板状逆Ｆアンテナに複数箇所設けられた複数の給電部のいずれか一つを選択する給電部切替手段と、前記給電部を切り替える毎に得られる受信レベルを相互に比較する受信レベル比較手段と、当該アンテナ装置に近接する指の位置を検出する位置検出手段と、前記検出された指の位置よって前記複数の給電部のいずれか一つを決定し、前記給電部切替手段により前記決定された給電部を選択する給電部決定手段と、第１の板状部材と、第２の板状部材と、前記第１の板状部材と前記第２の板状部材を複数箇所で接続するための複数の導電部材と、前記複数の導電部材のいずれか一つを選択して前記第１の板状部材と前記第２の板状部材を接続して前記板状逆Ｆアンテナを形成するアンテナ形成手段と、前記受信レベル比較手段の比較結果によって前記複数の導電部材のいずれか一つを決定し、前記アンテナ形成手段により前記決定された導電部材によって前記第１の板状部材と前記第２の板状部材を接続する導電部材決定手段と、を備えることを特徴とする。
また、本発明のアンテナ装置は、板状逆Ｆアンテナを有するアンテナ装置であって、前記板状逆Ｆアンテナに複数箇所設けられた複数の給電部のいずれか一つを選択する給電部切替手段と、当該アンテナ装置に近接する指の位置を検出する位置検出手段と、前記検出された指の位置よって前記複数の給電部のいずれか一つを決定し、前記給電部切替手段により前記決定された給電部を選択する給電部決定手段と、第１の板状部材と、第２の板状部材と、前記第１の板状部材と前記第２の板状部材を複数箇所で接続するための複数の導電部材と、前記複数の導電部材のいずれか一つを選択して前記第１の板状部材と前記第２の板状部材を接続して前記板状逆Ｆアンテナを形成するアンテナ形成手段と、前記位置検出手段で検出された指の位置よって前記複数の導電部材のいずれか一つを決定し、前記アンテナ形成手段により前記決定された導電部材によって前記第１の板状部材と前記第２の板状部材を接続する導電部材決定手段と、を備えることを特徴とする。
【００１３】
上記構成により、当該アンテナ装置に近接する指の位置を検出し、この検出結果によって板状逆Ｆアンテナに複数箇所設けられた複数の給電部の中で例えば近接した指に最も近い給電部を決定し、決定された給電部を選択する。これにより、使用者の指等がアンテナに近接した場合のＰＡＧが改善される。ここで、特許請求の範囲の給電部切替手段は実施形態のスイッチ７に相当し、位置検出手段は実施形態のセンサ部２２、２３、２４に相当し、給電部決定手段は実施形態の制御部２５に相当する。
【００１４】
本発明のアンテナ装置は、板状逆Ｆアンテナを有するアンテナ装置であって、第１の板状部材と、第２の板状部材と、前記第１の板状部材と前記第２の板状部材を複数箇所で接続するための複数の導電部材と、前記複数の導電部材のいずれか一つを選択して前記第１の板状部材と前記第２の板状部材を接続して前記板状逆Ｆアンテナを形成するアンテナ形成手段と、当該アンテナ装置に近接する指の位置を検出する位置検出手段と、前記検出された指の位置よって前記複数の導電部材のいずれか一つを決定し、前記アンテナ形成手段により前記決定された導電部材によって前記第１の板状部材と前記第２の板状部材を接続する導電部材決定手段と、を備えることを特徴とする。
【００１５】
上記構成により、第１の板状部材と前記第２の板状部材を複数箇所で接続するための複数の導電部材のいずれか一つを選択して第１の板状部材と第２の板状部材を接続して板状逆Ｆアンテナを形成するようにし、アンテナ装置に近接する指の位置を検出し、この検出された指の位置よって複数の導電部材のいずれか一つを決定し、アンテナ形成手段により、前記決定された導電部材によって第１の板状部材と第２の板状部材を接続する。これにより、使用者の指等がアンテナに近接した場合のＰＡＧが改善される。ここで、特許請求の範囲の第１の板状部材は実施形態の板状素子１に相当し、第２の板状部材は実施形態の地板３に相当し、導電部材は実施形態の短絡素子４、３０、３１に相当し、アンテナ形成手段は実施形態のスイッチ２０、２１に相当し、位置検出手段は実施形態のセンサ部２２、２３、２４に相当し、導電部材決定手段は実施形態の受信レベル検出部９に相当する。
【００１６】
本発明のアンテナ装置は、板状逆Ｆアンテナを有するアンテナ装置であって、前記板状逆Ｆアンテナに複数箇所設けられた複数の給電部のいずれか一つを選択する給電部切替手段と、前記給電部を切り替える毎に得られる受信レベルを相互に比較する受信レベル比較手段と、前記比較結果によって前記複数の給電部のいずれか一つを決定し、前記給電部切替手段により前記決定された給電部を選択する給電部決定手段と、第１の板状部材と、第２の板状部材と、前記第１の板状部材と前記第２の板状部材を複数箇所で接続するための複数の導電部材と、前記複数の導電部材のいずれか一つを選択して前記第１の板状部材と前記第２の板状部材を接続して前記板状逆Ｆアンテナを形成するアンテナ形成手段と、当該アンテナ装置に近接する指の位置を検出する位置検出手段と、前記検出された指の位置によって前記複数の導電部材のいずれか一つを決定し、前記アンテナ形成手段により前記決定された導電部材によって前記第１の板状部材と前記第２の板状部材を接続する導電部材決定手段と、を備えることを特徴とする。
【００１７】
上記構成により、板状逆Ｆアンテナに複数箇所設けられた複数の給電部を切り替える毎に得られる受信レベルを相互に比較し、この比較結果によって複数の給電部の中で例えば受信レベルが最も高い給電部を決定し、決定された給電部を選択する。また、第１の板状部材と第２の板状部材を複数箇所で接続するための複数の導電部材のいずれか一つを選択して第１の板状部材と第２の板状部材を接続して板状逆Ｆアンテナを形成するようにし、アンテナ装置に近接する指の位置を検出し、この検出された指の位置よって複数の導電部材のいずれか一つを決定し、アンテナ形成手段により、前記決定された導電部材によって第１の板状部材と第２の板状部材を接続する。これにより、使用者の指等がアンテナに近接した場合のＰＡＧが改善される。ここで、特許請求の範囲の給電部切替手段は実施形態のスイッチ７に相当し、比較手段は実施形態の演算処理部１０とメモリ部１１に相当し、給電部決定手段は実施形態の受信レベル検出部９に相当し、第１の板状部材は実施形態の板状素子１に相当し、第２の板状部材は実施形態の地板３に相当し、導電部材は実施形態の短絡素子４、３０、３１に相当し、アンテナ形成手段は実施形態のスイッチ３２、３３、３４に相当し、位置検出手段は実施形態のセンサ部３５に相当し、導電部材決定手段は実施形態の制御部２５に相当する。
【００２０】
【発明の実施の形態】
以下、図面を参照して本発明の実施形態を説明する。
本実施形態では、携帯電話等に内蔵する携帯無線機用アンテナ装置の構成例を示す。
【００２１】
（第１実施形態）
図１は本発明の第１実施形態に係る携帯無線機用アンテナ装置の構成例を示した図であり、図１（ａ）が上面図、図１（ｂ）が正面図、図１（ｂ）が側面図である。本実施形態の携帯無線機用アンテナ装置は、携帯電話等の携帯無線機１２に搭載されるものであり、板状素子１、スリット２、地板３、短絡素子４、給電部５、給電部６、スイッチ７、無線回路部８、受信レベル検出部９、演算処理部１０、メモリ部１１を有している。
【００２２】
上記図１の構成において、板状素子１は、例えば厚さ約０．３ｍｍの導体板で構成される。例えば板状素子１の長辺の長さは約３５ｍｍ、短辺の長さは約２０ｍｍに設定され、共振周波数を８００ＭＨｚに調節するために板状素子１にスリット２が設けられる。
【００２３】
板状素子１と地板３は、例えば幅約２ｍｍの短絡素子４によって電気的に接続される。短絡素子４の位置は板状素子１の長辺上部の中央付近に配置される。地板３は一般には無線機の回路基板のグランドであり、板状素子１に対する接地導体として動作する。板状素子１と接地導体３との間隔は例えば約５ｍｍに設定される。
【００２４】
板状素子１の上端部において、左端に給電部５及び右端に給電部６が設けられる。板状素子１、地板３、短絡素子４、給電部５及び給電部６によって板状逆Ｆアンテナが構成される。
【００２５】
次に本実施形態の動作について説明する。給電部５及び給電部６はスイッチ７に接続されており、このスイッチ７によって選択的に無線回路８に接続される。無線回路８で受信された受信レベルが受信レベル検出部９において検出される。受信レベル検出部９は演算処理部１０とメモリ部１１を備える。受信レベル検出部９は、スイッチ７を端子ａ側にして最初に給電部５を選択した場合の受信レベルをメモリ部１１に記憶し、その後、スイッチ７を端子ｂ側にして、給電部６を選択した場合の受信レベルとの比較を演算処理部１０で行う。この比較の結果、受信レベル検出部９は受信レベルが高い方の給電部の判別を行い、スイッチ７のスイッチ選択を決定する。
【００２６】
図２は図１に示す携帯無線機１２を使用者が手で保持して通話を行っている状態を示す図であり、図２（ａ）は斜視図、図２（ｂ）は図２（ａ）のＡ部の拡大図である。携帯無線機１２に内蔵される板状素子１は、使用者の頭部１３の反対側の面に配置される。一般に携帯無線機１２の長さは約１２０ｍｍ程度であり、使用者の指１４が板状素子１に近接し、ＰＡＧの劣化が発生する。
【００２７】
ここで、例えば、給電部６が選択されている場合について説明する。使用者の指１４が近接する板状素子１の部位によってＰＡＧの劣化量が変化する。ＰＡＧの劣化量が最も大きくなる点は高インピーダンス部１５である。これは、高インピーダンス部１５が給電部６から距離が最も離れた板状素子１の開放端であり、インピーダンスが高いため、近接する物体の影響を強く受けるためである。
【００２８】
また、この場合のＰＡＧは約−２１ｄＢｄである。なお使用者の指１４が板状素子１に近接しない場合のＰＡＧは約−１４ｄＢｄであり、指が近接することによるＰＡＧの劣化量は７ｄＢである。
【００２９】
これに対して、使用者の指１４が高インピーダンス部１５に近接した状態において、給電部５を選択した場合はＰＡＧの劣化が抑えられる。この時のＰＡＧは約−１７ｄＢｄとなり、指１４が近接することによるＰＡＧの劣化量は３ｄＢにまで改善される。本実施形態では、上記のように受信レベルの高い方の給電部を選択するように構成されているので、この場合は、受信レベル検出部９によりスイッチ７が端子ａに切り替えられて給電部５が選択されることになる。また、逆に使用者の指１４が高インピーダンス部１６に近接した場合は、受信レベル検出部９によりスイッチ７が端子ｂ側に切り替えられて給電部６が選択されることになり、ＰＡＧの劣化が抑えられる。
【００３０】
このように本実施形態における携帯無線機用アンテナ装置では、給電部５又は６の中間に短絡素子４を配置し、受信レベルが高い方の給電部を選択するように構成することで、指が近接した場合のＰＡＧの劣化量を抑えることができる。
【００３１】
なお、配置される板状素子１の大きさや配置構成は本実施形態の説明に限るものではなく、複数の給電部が配置され、それらを切替えることで高インピーダンス部の位置が変化できる構成であれば同等の効果が得られる。
【００３２】
（第２実施形態）
図３は本発明の第２実施形態に係る携帯無線機用アンテナ装置の構成例を示した図であり、図３（ａ）が上面図、図３（ｂ）が正面図、図３（ｃ）が側面図である。但し、図１の第１実施形態と同様の部分には同一の符号を付し、適宜その説明を省略する。
【００３３】
本実施形態の携帯無線機用アンテナ装置は、板状素子１の上端部において、左端に短絡素子１７及び右端に短絡素子１８が設けられる。板状素子１、地板３、短絡素子１７又は１８、給電部１９によって板状逆Ｆアンテナが構成される。短絡素子１７及び１８と地板３との間はスイッチ２０及び２１が挿入されて、短絡素子１７及び１８と地板３とが接続、分離されるようになっている。スイッチ２０及び２１が閉じた状態では短絡素子１７及び１８と地板３とが短絡され、開いた状態ではそれぞれが開放される。給電部１９は板状素子１の長辺上部の中央付近に配置される。他の構成は図１に示した第１実施形態と同様である。
【００３４】
ここで、短絡素子１７と地板３を短絡し且つ、短絡素子１８と地板３を開放した状態を第１の状態とする。逆に短絡素子１７と地板３を開放し且つ、短絡素子１８と地板３を短絡した状態を第２の状態とする。
【００３５】
次に本実施形態の動作について説明する。給電部１９は無線回路部８に接続される。受信レベル検出部９はスイッチ２０をオンし、スイッチ２１をオフすることで、最初に第１の状態の受信レベルをメモリ部１１に記憶する。その後、スイッチ２０をオフし、スイッチ２１をオンすることで、第２の状態の受信レベルとの比較を演算処理部１０で行う。この比較の結果、受信レベル検出部９は受信レベルが高い方の状態の判別を行い、スイッチ２０及び２１を制御して上記した第１又は第２の状態を決定する。
【００３６】
ここで、例えば、第２の状態について説明する。この場合、給電部１９及び短絡素子１８からの距離が最も離れた板状素子１上の開放端は図４に示すように高インピーダンス部１５となり、この高インピーダンス部１５に使用者の指１４が近接した場合ＰＡＧの劣化量が最も大きくなる。この場合のＰＡＧは約−２１ｄＢｄとなる。
【００３７】
なお、使用者の指１４が板状素子１に近接しない場合のＰＡＧは約−１４ｄＢｄであり、指１４が高インピーダンス部１５に近接することによるＰＡＧの劣化量は７ｄＢである。
【００３８】
これに対して、第１の状態を選択した場合、使用者の指１４が高インピーダンス部１５に近接した状態において、ＰＡＧの劣化が抑えられる。この時のＰＡＧは約−１７ｄＢｄとなり、指１４が近接することによるＰＡＧの劣化量は３ｄＢまで改善される。
【００３９】
したがって、上記のように受信レベルの高い方の状態を選択するように構成されているので、この場合は、受信レベル検出部９によりスイッチ２０がオンされて第１の状態が選択されることになる。また、逆に使用者の指１４が高インピーダンス部１６に近接した場合は、受信レベル検出部９によりスイッチ２１がオンされて第２の状態が選択されることになりＰＡＧの劣化が抑えられる。
【００４０】
このように本実施形態における携帯無線機用アンテナ装置では、短絡素子１７及び１８の中間に給電部１９を配置し、受信レベルが高くなるように短絡素子と地板３の短絡する位置を切替えることで、指が近接した場合のＰＡＧの劣化量を抑えることができる。
【００４１】
なお、配置される板状素子１の大きさや配置構成は本実施形態の説明に限るものではなく、複数の短絡素子が配置され、それらと地板３の短絡する位置を切替えることで高インピーダンス部の位置が変化できる構成であれば同等の効果が得られる。
【００４２】
（第３実施形態）
図５は本発明の第３実施形態に係る携帯無線機用アンテナ装置の構成例を示した図であり、図５（ａ）が上面図、図５（ｂ）が正面図、図５（ｃ）が側面図である。但し、図１の第１実施形態と同様の部分には同一の符号を付し、適宜その説明を省略する。
【００４３】
本実施形態の携帯無線機用アンテナ装置は、板状素子１近傍に同一形態のセンサ部２２、２３、２４を備える。これらセンサ部２２、２３、２４は指が板状素子１に近接した場合に指の配置位置を検知するものである。一つのセンサ部は例えば約１０ｍｍ四方の光センサで構成される。また、センサ部２２、２３、２４における検出結果は制御部２５において処理される。制御部２５は演算処理部２６とメモリ部２７を備える。
【００４４】
次に本実施形態の動作について説明する。制御部２５はセンサ部２２、２３、２４の検出結果をメモリ部２７に記憶し、各センサ部の検出結果の比較を行う。この比較の結果、指の近接位置の判定を行い、スイッチ７のスイッチ選択を決定する。
【００４５】
ここで、使用者の指１４が図６に示すように板状素子１上の高インピーダンス部１５に近接した場合について説明する。このとき、使用者の指１４はセンサ部２２によって検知されるため、制御部２５は指の配置位置が給電部５に近いと判定する。この場合は、制御部２５がスイッチ７を制御して端子ａ側に切り替え、近接した指１４に近い方の給電部５を選択する。これにより、指１４が近接した板状素子１の部位のインピーダンスを低下させ、ＰＡＧは−１７ｄＢｄとなり劣化が抑えられる。
【００４６】
逆に使用者の指２９が図６に示すように板状素子１上の高インピーダンス部１６に近接した場合について説明する。このとき、使用者の指２９はセンサ部２４によって検知されるため、これにより指２９の配置位置を判定する。この場合は、制御部２５がスイッチ７を制御して端子ｂ側に切り替え、近接した指２９に近い方の給電部６を選択する。これにより、指２９が近接した板状素子１の部分のインピーダンスを低下させ、ＰＡＧは−１７ｄＢｄとなり劣化が抑えられる。
【００４７】
また、例えば使用者の指２８が板状素子１の中央部に近接した場合について説明する。この場合は使用者の指２８はセンサ部２３によって検知される。この時、制御部２５はスイッチ７の以前の状態を保持し、給電部５又は６のいずれかが選択される。ここで、使用者の指２８が近接している板状素子１の中央部はいずれの給電部が選択された場合でも高インピーダンス部とはならない。したがってＰＡＧの劣化が抑えられ、ＰＡＧは約−１７ｄＢｄとなる。
【００４８】
このように本実施形態における携帯無線機用アンテナ装置では、給電部５又は６の中間に短絡素子４を配置し、板状素子１近傍に指を検知するセンサ部を設けることにより、指の位置によって給電部を選択することで、指が近接した場合のＰＡＧの劣化量を抑えることができる。
【００４９】
なお、配置される板状素子１の大きさや配置構成又はセンサ部２２〜２４における検出方法は本実施形態の説明に限るものではなく、複数の給電部と指を検知する検出部を備え、その結果にしたがって複数の給電部を切替えることで高インピーダンス部の位置が変化できる構成であれば同様の効果が得られる。
【００５０】
また、指の近接位置の検出結果にしたがって、第２実施形態の図３に示すように板状素子１と地板３を接続する複数の短絡素子を切り替える構成であっても同様の効果が得られる。
【００５１】
（第４実施形態）
図７は本発明の第４実施形態に係る携帯無線機用アンテナ装置の構成例を示したブロック図であり、図７（ａ）が上面図、図７（ｂ）が正面図、図７（ｃ）が側面図である。但し、図１の第１実施形態と同様の部分には同一の符号を付し、適宜その説明を省略する。
【００５２】
本実施形態の携帯無線機用アンテナ装置は、板状素子１、地板３、短絡素子４、給電部５、給電部６、スイッチ７、無線回路部８、受信レベル検出部９、制御部２５、演算処理部２６、メモリ部２７、短絡素子３０、短絡素子３１、スイッチ３２、スイッチ３３、スイッチ３４、センサ部３５を有している。
【００５３】
図７において、短絡素子３０及び３１は例えば厚さ約０.３ｍｍの導体板で構成される。これら短絡素子３０及び３１は短絡素子４のそれぞれ左側近傍及び右側近傍に配置される。短絡素子４、３０及び３１と地板３との間にスイッチ３２、３３及び３４がそれぞれ接続される。スイッチ３２、３３及び３４が閉じた状態では短絡素子４、３０及び３１と地板３とが短絡され、開いた状態ではそれぞれが開放される。
【００５４】
ここで、接続素子４と地板３を短絡し且つ短絡素子３０及び３１と地板３を開放した状態を第１の状態とする。短絡素子３０と地板３を短絡し且つ短絡素子４及び３１と地板３を開放した状態を第２の状態とする。また短絡素子３１と地板３を短絡し且つ短絡素子４及び３０と地板３を開放した状態を第３の状態とする。
【００５５】
制御部２５はセンサ部３５の検出結果から使用者の指の近接の有無の判定を行い、スイッチ３２、３３及び３４を制御し、第１、第２又は第３いずれかの状態を選択する。
【００５６】
ここで、例えば、使用者の指が板状素子１に近接していない、すなわちセンサ部３５が指を検出していない場合においては、制御部２５によりスイッチ３２が短絡され、第１の状態が選択される。
【００５７】
図８は板状逆Ｆアンテナの共振周波数の変動を示す特性図である。上記の指が近接していない状態のＶＳＷＲ特性は図８に示したグラフ曲線３６となる。この場合は共振周波数（ＶＳＷＲが最小となる周波数）が９００ＭＨｚとなる。
【００５８】
次に図９に示すように、使用者の指１４が板状素子１上の高インピーダンス部１５に近接した場合、第１実施形態で説明したように受信レベル検出部９がスイッチ７を制御して給電部５又は６に切り替えた時の受信レベルを比較して、受信レベルが高い給電部５を選択する。
【００５９】
このとき、制御部２５により仮にスイッチ３２が短絡されて、短絡素子４が選択された第１の状態であったとすれば、使用者の指１４と板状素子１の間の容量性リアクタンスが増加するため、板状逆ＦアンテナのＶＳＷＲの周波数特性はグラフ曲線３６の状態からグラフ曲線３７のように変化する。すなわち共振周波数は８００ＭＨｚに低下する。この場合、９００ＭＨｚにおけるＶＳＷＲは約５となり、インピーダンスの不整合損失が大きくなる。この場合のＰＡＧは約−１７ｄＢｄである。
【００６０】
ここで、本発明の実施形態のアンテナ装置では、センサ部３５で指が検出されていれば、制御部２５はスイッチ３３を短絡し、近接した指１４に近い短絡素子３０を用いて板状素子１と地板３を接続して第２の状態を選択するように動作し、ＶＳＷＲを改善する。このように制御すれば、グラフ曲線３７に示した共振周波数（８００ＭＨｚ）がグラフ曲線３８に示されるように８８０ＭＨｚまで高くなる。この場合、９００ＭＨｚにおけるＶＳＷＲは約２となり、インピーダンスの不整合損失が低減される。この場合のＰＡＧは約−１５．５ｄＢｄに改善される。
【００６１】
これに対して使用者の指１４が高インピーダンス部１６に近接した時は、制御部２５はスイッチ３４を短絡し、近接した指１４に近い短絡素子３１を用いて板状素子１と地板３を接続して第３の状態を選択するように動作し、ＶＳＷＲを改善する。同様にこの場合のＰＡＧは−１５．５ｄＢｄとなる。
【００６２】
このように本実施形態における携帯無線機用アンテナ装置では、給電部５又は６の中間に短絡素子４、短絡素子３０及び３１を配置し、指を検知するセンサ部３５を備え、最初に受信レベルが高い方の給電部を選択し、次に指の近接の有無によって短絡素子が選択されるように構成することで、ＶＳＲＷの改善も行って、指が近接した場合のＰＡＧの劣化量を第１〜第３実施形態に比べてさらに改善することができる。
【００６３】
なお、配置される板状素子１及び短絡素子の大きさや配置構成及びは本実施形態の説明に限るものではなく、複数の給電部と、複数の短絡素子と、センサ部が配置され、それらを切替えることで高インピーダンス部の位置と共振周波数を変化できる構成であれば同様の効果が得られる。
【００６４】
（第５実施形態）
図１０は本発明の第５実施形態に係る携帯無線機用アンテナ装置の構成例を示したブロック図であり、図１０（ａ）が上面図、図１０（ｂ）が正面図、図１０（ｃ）が側面図である。但し、図７の第４実施形態と同様の部分には同一の符号を付し、適宜その説明を省略する。本実施形態の携帯無線機用アンテナ装置は、上記した第４実施形態の構成からセンサ部を削除した構成を有している。
【００６５】
次に本実施形態の動作について説明する。例えば、図１１に示すように、使用者の指１４が高インピーダンス部１５に近接した場合において、受信レベル検出部９は給電部５又は６を選択してそれぞれのレベルを検出する動作を行う。その後、受信レベル検出部９は上記検出結果をもとに指の近接の有無の判定を行い、スイッチ３２、３３及び３４を制御し、第４実施形態と同様の第１、第２又は第３の状態を選択する。
【００６６】
上記のように使用者の指１４が高インピーダンス部１５に近接した場合、第１実施形態で説明したように受信レベル検出部９は受信レベルの高い方を選択するように構成されているので、スイッチ７を端子ａ側に制御して給電部５を選択する。また、受信レベル検出部９は給電部５及び６の受信レベルが異なるため、使用者の指１４が給電部５側に近いのか或いは、給電部６側に近いのかを判別し、この場合は給電部５側に近いので、スイッチ３３を短絡して第２の状態を選択することによりＶＳＷＲを改善することになる。このとき、第４実施形態と同様の効果が得られ、ＰＡＧは約−１５．５ｄＢｄに改善される。
【００６７】
これに対して使用者の指１４が高インピーダンス部１６に近接した時は、上記と同様の制御により受信レベル検出部９は給電部６及び第３の状態を選択し、この場合も、ＰＡＧは−１５．５ｄＢｄとなる。
【００６８】
このように本実施形態における携帯無線機用アンテナ装置では、給電部５及び６の中間に短絡素子４、短絡素子３０及び３１を配置し、給電部５又は６の受信レベルの比較により、指の近接の有無及び位置を検知し、最初に受信レベルが高い方の給電部を選択し、その後、近接した指の位置により短絡素子４、３０又は３１が選択されるように構成することで、指を直接検知するセンサ部を配置することなく、ＶＳＲＷの改善も行って、指が近接した場合のＰＡＧの劣化量を著しく抑えることができる。
【００６９】
なお、配置される板状素子１及び短絡素子の大きさや配置構成は本実施形態の説明に限るものではなく、複数の給電部と、複数の短絡素子と、受信レベルを比較する検知部を備え、それらを切替えることで高インピーダンス部の位置と共振周波数が変化できる構成であれば同様の効果が得られる。
【００７０】
上述したように、本実施形態によれば、板状逆Ｆアンテナの給電位置を最も受信レベルが高くなるように選択することにより、指の位置を検出することなく、指がアンテナに近接した場合のＰＡＧを改善することができる。
【００７１】
また、板状逆Ｆアンテナを形成する第１の板状部材と第２の板状部材を接続する導電部材の位置を最も受信レベルが高くなるように選択することにより、指の位置を検出することなく、指がアンテナに近接した場合のＰＡＧを改善することができる。
【００７２】
また、板状逆Ｆアンテナの給電位置を近接する指の位置によって選択することにより、指がアンテナに近接した場合のＰＡＧを改善することができる。
【００７３】
また、板状逆Ｆアンテナを形成する第１の板状部材と第２の板状部材を接続する導電部材の位置を近接する指の位置によって選択することにより、指がアンテナに近接した場合のＰＡＧを改善することができる。
【００７４】
また、板状逆Ｆアンテナの給電位置を最も受信レベルが高くなるように選択すると共に、板状逆Ｆアンテナを形成する第１の板状部材と第２の板状部材を接続する導電部材の位置を近接する指の位置によって選択することにより、指がアンテナに近接した場合のＰＡＧを著しく改善することができる。
【００７５】
また、板状逆Ｆアンテナの給電位置を最も受信レベルが高くなるように選択すると共に、板状逆Ｆアンテナを形成する第１の板状部材と第２の板状部材を接続する導電部材の位置を最も受信レベルが高くなるように選択することにより、指の位置を検出することなく、指がアンテナに近接した場合のＰＡＧを著しく改善することができる。
【００７６】
【発明の効果】
以上説明したように本発明によれば、板状逆Ｆアンテナの給電位置を最も受信レベルが高くなるように選択することにより、使用者の指等の位置を検出することなく、携帯無線機等において使用者の指等がアンテナに近接した場合のＰＡＧを改善することが可能となる。
【図面の簡単な説明】
【図１】本発明の第１実施形態に係る携帯無線機用アンテナ装置の構成例を示した上面図、正面図、及び側面図
【図２】図１に示す携帯無線機を使用者が手で保持して通話を行っている状態を示す説明図
【図３】本発明の第２実施形態に係る携帯無線機用アンテナ装置の構成例を示した上面図、正面図、及び側面図
【図４】図３に示す携帯無線機を使用者が手で保持して通話を行っている状態を示す説明図
【図５】本発明の第３実施形態に係る携帯無線機用アンテナ装置の構成例を示した上面図、正面図、及び側面図
【図６】図５に示す携帯無線機を使用者が手で保持して通話を行っている状態を示す説明図
【図７】本発明の第４実施形態に係る携帯無線機用アンテナ装置の構成例を示した上面図、正面図、及び側面図
【図８】使用者の指がアンテナ高インピーダンス部に近接した場合の周波数変動量を示した特性図
【図９】図７に示す携帯無線機を使用者が手で保持して通話を行っている状態を示す説明図
【図１０】本発明の第５実施形態に係る携帯無線機用アンテナ装置の構成例を示した上面図、正面図、及び側面図
【図１１】図１０に示す携帯無線機を使用者が手で保持して通話を行っている状態を示す説明図
【符号の説明】
１板状素子
２スリット
３地板
４、１７、１８、３０、３１短絡素子
５、６、１９給電部
７、２０、２１、３２、３３、３４スイッチ
８無線回路部
９受信レベル検出部
１０、２６演算処理部
１１、２７メモリ部
１２携帯無線機
２２、２３、２４、３５センサ部
２５制御部[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an antenna device built in a small wireless device such as a mobile phone (hereinafter abbreviated as a mobile phone), and particularly when a user holds the wireless device by hand and a finger approaches the built-in antenna. The present invention relates to gain improvement of an antenna device.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, in mobile phone antennas, a configuration in which diversity reception is performed using an external telescopic antenna and a built-in antenna disposed on the opposite side of the human body during a call has been widely adopted. In a call state in which such a mobile phone is held by the user's hand, the conventional built-in antenna is generally arranged at a position closer to the hand than the telescopic antenna. For this reason, the conventional built-in antenna has a problem that the antenna performance is likely to deteriorate due to electromagnetic interaction between the finger and the antenna.
[0003]
In this case, the horizontal plane pattern averaging gain (hereinafter referred to as PAG) in the call state is deteriorated by about 7 dB as compared with the case where the finger is not close to the antenna. One factor of this performance deterioration is impedance mismatch loss caused by a change in the resonance frequency of the built-in antenna due to the proximity of the finger.
[0004]
In order to solve this problem, for example, a configuration in which the resonance frequency is changed by switching a short-circuit element of an inverted-F antenna with a switch, as disclosed in Japanese Patent Application Laid-Open No. 2000-114856 or Japanese Patent Application Laid-Open No. 10-224142. Has been proposed.
[0005]
Japanese Patent Application Laid-Open No. 10-190345 discloses that the resonance frequency is changed by changing the capacitive reactance provided in the power feeding section. Japanese Patent Laid-Open No. 11-145852 proposes a configuration using a technique for switching matching circuits.
[0006]
[Problems to be solved by the invention]
However, the above-described conventional built-in antenna has an effect of preventing impedance mismatch loss due to a change in resonance frequency, but it cannot suppress efficiency deterioration due to the proximity of a finger. In that case, the PAG in the call state has a problem that it deteriorates by about 5 dB as compared with the case where the finger is not close to the antenna.
[0007]
The present invention has been made in view of the above circumstances, and an object thereof is to provide an antenna device capable of improving PAG when a finger or the like is close to the antenna in a portable wireless device or the like.
[0008]
[Means for Solving the Problems]
The antenna device of the present invention is an antenna device having a plate-like inverted F antenna, and a feeding unit switching means for selecting any one of a plurality of feeding units provided at a plurality of locations on the plate-like inverted F antenna; Position detecting means for detecting the position of a finger in proximity to the antenna device, and determining any one of the plurality of power feeding units according to the detected finger position, and the power feeding determined by the power feeding unit switching means Power supply unit determining means for selecting a unit.
[0012]
Further, the antenna device of the present invention is an antenna device having a plate-like inverted F antenna, and feed portion switching means for selecting any one of a plurality of feeding portions provided at a plurality of locations on the plate-like inverted F antenna. And reception level comparison means for comparing reception levels obtained each time the power feeding unit is switched, position detection means for detecting the position of a finger close to the antenna device, and the detected finger position Determining one of a plurality of power supply units, power supply unit determining means for selecting the power supply unit determined by the power supply unit switching unit, a first plate member, a second plate member, The first plate member is selected by selecting one of the plurality of conductive members for connecting the first plate member and the second plate member at a plurality of locations, and the plurality of conductive members. And the second plate-like member connected to the plate One of the plurality of conductive members is determined according to a comparison result between an antenna forming unit that forms an inverted F antenna and the reception level comparing unit, and the first conductive member determined by the antenna forming unit determines the first A conductive member determining means for connecting the plate-like member and the second plate-like member.
Further, the antenna device of the present invention is an antenna device having a plate-like inverted F antenna, and feed portion switching means for selecting any one of a plurality of feeding portions provided at a plurality of locations on the plate-like inverted F antenna. A position detection unit that detects a position of a finger that is close to the antenna device, and determines one of the plurality of power feeding units according to the detected finger position, and the determination is performed by the power feeding unit switching unit. For connecting the power feeding unit determining means for selecting the power feeding unit, the first plate member, the second plate member, the first plate member, and the second plate member at a plurality of locations. A plurality of conductive members and an antenna that selects one of the plurality of conductive members and connects the first plate-like member and the second plate-like member to form the plate-like inverted F antenna. The position of the finger detected by the forming means and the position detecting means. Conductive member determining means for determining any one of the plurality of conductive members, and connecting the first plate member and the second plate member by the conductive member determined by the antenna forming means; It is characterized by providing.
[0013]
With the above configuration, the position of the finger that is close to the antenna device is detected, and the power supply unit that is closest to the close finger, for example, is determined from among the plurality of power supply units that are provided at a plurality of locations on the plate-like inverted F antenna based on the detection result. Then, the determined power feeding unit is selected. This improves the PAG when the user's finger or the like is close to the antenna. Here, the power feeding unit switching unit in the claims corresponds to the switch 7 of the embodiment, the position detection unit corresponds to the sensor units 22, 23, and 24 of the embodiment, and the power feeding unit determination unit is the control unit of the embodiment. This corresponds to 25.
[0014]
The antenna device of the present invention is an antenna device having a plate-like inverted F antenna, and includes a first plate-like member, a second plate-like member, the first plate-like member, and the second plate-like shape. A plurality of conductive members for connecting members at a plurality of locations, and selecting any one of the plurality of conductive members to connect the first plate member and the second plate member to the plate One of the plurality of conductive members is determined according to the antenna forming means for forming the inverted F antenna, the position detecting means for detecting the position of the finger in proximity to the antenna device, and the detected finger position. And conductive member determining means for connecting the first plate-like member and the second plate-like member by the conductive member determined by the antenna forming means.
[0015]
With the above configuration, the first plate member and the second plate are selected by selecting any one of a plurality of conductive members for connecting the first plate member and the second plate member at a plurality of locations. A plate-shaped inverted F antenna is connected to detect a position of a finger close to the antenna device, and determine one of a plurality of conductive members according to the detected position of the finger, The first plate-like member and the second plate-like member are connected by the antenna forming means by the determined conductive member. This improves the PAG when the user's finger or the like is close to the antenna. Here, the first plate-like member in the claims corresponds to the plate-like element 1 of the embodiment, the second plate-like member corresponds to the ground plate 3 of the embodiment, and the conductive member is the short-circuit element of the embodiment. 4, 30, and 31, the antenna forming unit corresponds to the switches 20 and 21 of the embodiment, the position detection unit corresponds to the sensor units 22, 23, and 24 of the embodiment, and the conductive member determination unit is This corresponds to the reception level detection unit 9.
[0016]
The antenna device of the present invention is an antenna device having a plate-like inverted F antenna, and a feeding unit switching means for selecting any one of a plurality of feeding units provided at a plurality of locations on the plate-like inverted F antenna; A reception level comparison unit that compares reception levels obtained each time the power supply unit is switched, and determines one of the plurality of power supply units according to the comparison result, and the determination is performed by the power supply unit switching unit. Power supply unit determining means for selecting a power supply unit, a first plate member, a second plate member, and the first plate member and the second plate member for connecting at a plurality of locations Antenna formation for selecting a plurality of conductive members and selecting one of the plurality of conductive members to connect the first plate-like member and the second plate-like member to form the plate-like inverted F antenna Means and a finger close to the antenna device. Position detecting means for detecting a position, and one of the plurality of conductive members is determined according to the detected finger position, and the first plate-like member is determined by the conductive member determined by the antenna forming means. And a conductive member determining means for connecting the second plate-shaped member.
[0017]
With the above configuration, the reception levels obtained each time a plurality of power feeding units provided in a plurality of places on the plate-like inverted F antenna are switched are compared with each other, and the reception level is the highest among the plurality of power feeding units according to the comparison result. A power feeding unit is determined, and the determined power feeding unit is selected. In addition, the first plate member and the second plate member are selected by selecting any one of a plurality of conductive members for connecting the first plate member and the second plate member at a plurality of locations. The plate-shaped inverted F antenna is connected to detect the position of the finger close to the antenna device, and any one of the plurality of conductive members is determined according to the detected finger position, and the antenna forming means Thus, the first plate-like member and the second plate-like member are connected by the determined conductive member. This improves the PAG when the user's finger or the like is close to the antenna. Here, the power supply switching unit in the claims corresponds to the switch 7 of the embodiment, the comparison unit corresponds to the arithmetic processing unit 10 and the memory unit 11 of the embodiment, and the power supply determination unit is the reception level of the embodiment. The first plate member corresponds to the detection unit 9, the first plate member corresponds to the plate element 1 of the embodiment, the second plate member corresponds to the ground plate 3 of the embodiment, and the conductive member corresponds to the short circuit element 4 of the embodiment. , 30 and 31, the antenna forming means corresponds to the switches 32, 33 and 34 of the embodiment, the position detecting means corresponds to the sensor unit 35 of the embodiment, and the conductive member determining means is the control unit 25 of the embodiment. It corresponds to.
[0020]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In this embodiment, a configuration example of an antenna device for a portable wireless device built in a mobile phone or the like is shown.
[0021]
(First embodiment)
FIG. 1 is a diagram showing a configuration example of an antenna device for a portable wireless device according to a first embodiment of the present invention. FIG. 1 (a) is a top view, FIG. 1 (b) is a front view, and FIG. ) Is a side view. The antenna device for a portable wireless device according to the present embodiment is mounted on a portable wireless device 12 such as a mobile phone. , Switch 7, wireless circuit unit 8, reception level detection unit 9, arithmetic processing unit 10, and memory unit 11.
[0022]
In the configuration shown in FIG. 1, the plate-like element 1 is constituted by a conductor plate having a thickness of about 0.3 mm, for example. For example, the length of the long side of the plate-like element 1 is set to about 35 mm, the length of the short side is set to about 20 mm, and a slit 2 is provided in the plate-like element 1 in order to adjust the resonance frequency to 800 MHz.
[0023]
The plate-like element 1 and the ground plane 3 are electrically connected by a short-circuit element 4 having a width of about 2 mm, for example. The position of the short-circuit element 4 is arranged near the center of the upper part of the long side of the plate-like element 1. The ground plane 3 is generally a ground of a circuit board of a radio device and operates as a ground conductor for the plate-like element 1. The distance between the plate element 1 and the ground conductor 3 is set to about 5 mm, for example.
[0024]
In the upper end portion of the plate-like element 1, a power feeding unit 5 is provided at the left end and a power feeding unit 6 is provided at the right end. A plate-like inverted F antenna is constituted by the plate-like element 1, the ground plane 3, the short-circuit element 4, the power feeding unit 5 and the power feeding unit 6.
[0025]
Next, the operation of this embodiment will be described. The power feeding unit 5 and the power feeding unit 6 are connected to a switch 7, and the switch 7 selectively connects to the radio circuit 8. The reception level received by the radio circuit 8 is detected by the reception level detector 9. The reception level detection unit 9 includes an arithmetic processing unit 10 and a memory unit 11. The reception level detection unit 9 stores the reception level in the memory unit 11 when the power supply unit 5 is first selected with the switch 7 set to the terminal a side, and then sets the power supply unit 6 with the switch 7 set to the terminal b side. Comparison with the reception level when selected is performed by the arithmetic processing unit 10. As a result of the comparison, the reception level detection unit 9 determines the power supply unit with the higher reception level and determines the switch selection of the switch 7.
[0026]
2 is a diagram showing a state in which the user is holding the portable wireless device 12 shown in FIG. 1 by hand, and FIG. 2A is a perspective view, and FIG. 2B is a diagram in FIG. It is an enlarged view of the A section of a). The plate-like element 1 built in the portable wireless device 12 is disposed on the opposite surface of the user's head 13. In general, the length of the portable wireless device 12 is about 120 mm, and the user's finger 14 comes close to the plate-like element 1, causing deterioration of the PAG.
[0027]
Here, for example, a case where the power feeding unit 6 is selected will be described. The amount of degradation of the PAG changes depending on the part of the plate-like element 1 to which the user's finger 14 is close. The high impedance portion 15 is the point where the amount of degradation of the PAG is the largest. This is because the high impedance part 15 is the open end of the plate-like element 1 farthest from the power supply part 6 and has a high impedance, so that it is strongly influenced by an adjacent object.
[0028]
In this case, the PAG is about -21 dBd. Note that the PAG when the user's finger 14 is not close to the plate-like element 1 is about −14 dBd, and the degradation amount of the PAG due to the proximity of the finger is 7 dB.
[0029]
On the other hand, when the power supply unit 5 is selected in the state where the user's finger 14 is close to the high impedance unit 15, the deterioration of the PAG is suppressed. The PAG at this time is about −17 dBd, and the amount of degradation of the PAG due to the proximity of the finger 14 is improved to 3 dB. In the present embodiment, the power supply unit with the higher reception level is selected as described above. In this case, the switch 7 is switched to the terminal a by the reception level detection unit 9, and the power supply unit 5 is selected. Will be selected. On the other hand, when the user's finger 14 is close to the high impedance unit 16, the switch 7 is switched to the terminal b side by the reception level detection unit 9, and the power supply unit 6 is selected. Is suppressed.
[0030]
As described above, in the antenna device for a portable wireless device according to the present embodiment, the short-circuit element 4 is arranged in the middle of the power feeding unit 5 or 6, and the power feeding unit with the higher reception level is selected. The amount of deterioration of the PAG when close to each other can be suppressed.
[0031]
The size and arrangement configuration of the plate-like element 1 to be arranged are not limited to the description of the present embodiment, and a configuration in which a plurality of power feeding units are arranged and the position of the high impedance unit can be changed by switching them. The same effect can be obtained.
[0032]
(Second Embodiment)
FIG. 3 is a diagram showing a configuration example of an antenna device for a portable wireless device according to the second embodiment of the present invention. FIG. 3 (a) is a top view, FIG. 3 (b) is a front view, and FIG. ) Is a side view. However, the same parts as those in the first embodiment in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.
[0033]
In the antenna device for portable wireless devices of the present embodiment, a short-circuit element 17 is provided at the left end and a short-circuit element 18 is provided at the right end in the upper end portion of the plate-like element 1. A plate-like inverted F antenna is configured by the plate-like element 1, the ground plane 3, the short-circuit element 17 or 18, and the power feeding unit 19. Switches 20 and 21 are inserted between the short-circuit elements 17 and 18 and the ground plane 3 so that the short-circuit elements 17 and 18 and the ground plane 3 are connected and separated. When the switches 20 and 21 are closed, the short-circuit elements 17 and 18 and the ground plane 3 are short-circuited, and when they are opened, each is opened. The power feeding unit 19 is arranged near the center of the upper part of the long side of the plate-like element 1. Other configurations are the same as those of the first embodiment shown in FIG.
[0034]
Here, let the short circuit element 17 and the ground plane 3 be short-circuited, and let the state which open | released the short circuit element 18 and the ground plane 3 be a 1st state. Conversely, the state in which the short-circuit element 17 and the ground plane 3 are opened and the short-circuit element 18 and the ground plane 3 are short-circuited is defined as a second state.
[0035]
Next, the operation of this embodiment will be described. The power feeding unit 19 is connected to the wireless circuit unit 8. The reception level detection unit 9 turns on the switch 20 and turns off the switch 21, thereby first storing the reception level in the first state in the memory unit 11. Thereafter, the arithmetic processing unit 10 compares the reception level in the second state by turning off the switch 20 and turning on the switch 21. As a result of the comparison, the reception level detection unit 9 determines the state with the higher reception level, and controls the switches 20 and 21 to determine the first or second state described above.
[0036]
Here, for example, the second state will be described. In this case, the open end on the plate-like element 1 farthest from the power supply unit 19 and the short-circuit element 18 becomes a high impedance part 15 as shown in FIG. 4, and the user's finger 14 is placed on the high impedance part 15. When close to each other, the amount of degradation of the PAG becomes the largest. In this case, the PAG is about -21 dBd.
[0037]
Note that the PAG when the user's finger 14 is not close to the plate-like element 1 is about −14 dBd, and the amount of deterioration of the PAG due to the finger 14 being close to the high impedance portion 15 is 7 dB.
[0038]
On the other hand, when the first state is selected, deterioration of the PAG can be suppressed in a state where the user's finger 14 is close to the high impedance unit 15. The PAG at this time is about −17 dBd, and the amount of degradation of the PAG caused by the proximity of the finger 14 is improved to 3 dB.
[0039]
Accordingly, since the state with the higher reception level is selected as described above, in this case, the switch 20 is turned on by the reception level detection unit 9 to select the first state. Become. On the other hand, when the user's finger 14 is close to the high impedance unit 16, the switch 21 is turned on by the reception level detection unit 9 and the second state is selected, so that deterioration of the PAG is suppressed.
[0040]
In this way, in the portable radio antenna apparatus according to the present embodiment, the feeding unit 19 is disposed between the short-circuit elements 17 and 18, and the position where the short-circuit element and the ground plane 3 are short-circuited is switched so that the reception level is high. The amount of degradation of the PAG when the finger is close can be suppressed.
[0041]
In addition, the size and arrangement configuration of the plate-like element 1 to be arranged are not limited to the description of the present embodiment, and a plurality of short-circuit elements are arranged, and the high-impedance portion of the high-impedance part can be changed by switching the short-circuit position between them and the ground plane 3 If the position can be changed, the same effect can be obtained.
[0042]
(Third embodiment)
FIG. 5 is a diagram showing a configuration example of an antenna device for a portable wireless device according to a third embodiment of the present invention, where FIG. 5 (a) is a top view, FIG. 5 (b) is a front view, and FIG. ) Is a side view. However, the same parts as those in the first embodiment in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.
[0043]
The antenna device for a portable wireless device according to the present embodiment includes sensor units 22, 23, and 24 having the same form near the plate-like element 1. These sensor units 22, 23, and 24 detect the arrangement position of the finger when the finger approaches the plate-like element 1. One sensor unit is composed of, for example, an optical sensor of about 10 mm square. Further, detection results in the sensor units 22, 23, and 24 are processed in the control unit 25. The control unit 25 includes an arithmetic processing unit 26 and a memory unit 27.
[0044]
Next, the operation of this embodiment will be described. The control unit 25 stores the detection results of the sensor units 22, 23, and 24 in the memory unit 27, and compares the detection results of the sensor units. As a result of the comparison, the proximity position of the finger is determined, and the switch selection of the switch 7 is determined.
[0045]
Here, a case where the user's finger 14 is close to the high impedance portion 15 on the plate-like element 1 as shown in FIG. 6 will be described. At this time, since the user's finger 14 is detected by the sensor unit 22, the control unit 25 determines that the finger placement position is close to the power supply unit 5. In this case, the control unit 25 controls the switch 7 to switch to the terminal a side, and selects the power feeding unit 5 closer to the adjacent finger 14. Thereby, the impedance of the site | part of the plate-shaped element 1 to which the finger | toe 14 approached is reduced, PAG becomes -17dBd and degradation is suppressed.
[0046]
Conversely, the case where the user's finger 29 is close to the high impedance portion 16 on the plate-like element 1 as shown in FIG. 6 will be described. At this time, since the user's finger 29 is detected by the sensor unit 24, the arrangement position of the finger 29 is determined thereby. In this case, the control unit 25 controls the switch 7 to switch to the terminal b side, and selects the power feeding unit 6 closer to the adjacent finger 29. As a result, the impedance of the portion of the plate-like element 1 where the finger 29 is close is lowered, and the PAG becomes -17 dBd, and the deterioration is suppressed.
[0047]
For example, a case where the user's finger 28 comes close to the center of the plate-like element 1 will be described. In this case, the user's finger 28 is detected by the sensor unit 23. At this time, the control unit 25 holds the previous state of the switch 7 and either the power feeding unit 5 or 6 is selected. Here, the central portion of the plate-like element 1 to which the user's finger 28 is close does not become a high impedance portion regardless of which power feeding portion is selected. Therefore, the deterioration of the PAG is suppressed, and the PAG becomes about −17 dBd.
[0048]
As described above, in the antenna device for a portable wireless device according to the present embodiment, the short-circuit element 4 is disposed in the middle of the power feeding unit 5 or 6, and the sensor unit that detects the finger is provided in the vicinity of the plate-like element 1. By selecting the power supply unit by the method, it is possible to suppress the deterioration amount of the PAG when the finger is in proximity.
[0049]
In addition, the detection method in the magnitude | size and arrangement structure of the plate-shaped element 1 arrange | positioned, or the sensor parts 22-24 is not restricted to description of this embodiment, It is equipped with the detection part which detects a some electric power feeding part and a finger | toe, Similar effects can be obtained as long as the position of the high impedance portion can be changed by switching a plurality of power feeding portions according to the result.
[0050]
Further, according to the detection result of the proximity position of the finger, the same effect can be obtained even in a configuration in which a plurality of short-circuit elements connecting the plate-like element 1 and the ground plane 3 are switched as shown in FIG. 3 of the second embodiment. .
[0051]
(Fourth embodiment)
FIG. 7 is a block diagram showing a configuration example of an antenna device for a portable wireless device according to a fourth embodiment of the present invention, where FIG. 7A is a top view, FIG. 7B is a front view, and FIG. c) is a side view. However, the same parts as those in the first embodiment in FIG. 1 are denoted by the same reference numerals, and the description thereof is omitted as appropriate.
[0052]
The antenna device for a portable wireless device of this embodiment includes a plate-like element 1, a ground plane 3, a short-circuit element 4, a power feeding unit 5, a power feeding unit 6, a switch 7, a radio circuit unit 8, a reception level detecting unit 9, a control unit 25, An arithmetic processing unit 26, a memory unit 27, a short circuit element 30, a short circuit element 31, a switch 32, a switch 33, a switch 34, and a sensor unit 35 are provided.
[0053]
In FIG. 7, the short-circuit elements 30 and 31 are formed of a conductor plate having a thickness of about 0.3 mm, for example. These short-circuit elements 30 and 31 are arranged near the left side and the right side of the short-circuit element 4, respectively. Switches 32, 33 and 34 are connected between the short-circuit elements 4, 30 and 31 and the ground plane 3, respectively. In the state where the switches 32, 33 and 34 are closed, the short-circuit elements 4, 30 and 31 and the ground plane 3 are short-circuited, and in the opened state, each is opened.
[0054]
Here, a state in which the connection element 4 and the ground plane 3 are short-circuited and the short-circuit elements 30 and 31 and the ground plane 3 are opened is a first state. A state in which the short-circuit element 30 and the ground plane 3 are short-circuited and the short-circuit elements 4 and 31 and the ground plane 3 are opened is defined as a second state. Moreover, the state which short-circuited the short circuit element 31 and the ground plane 3 and open | released the short circuit elements 4 and 30 and the ground plane 3 is made into a 3rd state.
[0055]
The control unit 25 determines the presence or absence of the user's finger from the detection result of the sensor unit 35, controls the switches 32, 33 and 34, and selects one of the first, second and third states.
[0056]
Here, for example, when the user's finger is not close to the plate-like element 1, that is, when the sensor unit 35 is not detecting the finger, the switch 32 is short-circuited by the control unit 25, and the first state is Selected.
[0057]
FIG. 8 is a characteristic diagram showing fluctuations in the resonance frequency of the plate-like inverted F antenna. The VSWR characteristic when the finger is not in proximity is the graph curve 36 shown in FIG. In this case, the resonance frequency (frequency at which VSWR is minimized) is 900 MHz.
[0058]
Next, as shown in FIG. 9, when the user's finger 14 comes close to the high impedance part 15 on the plate-like element 1, the reception level detection part 9 controls the switch 7 as described in the first embodiment. Then, the reception level when the power supply unit 5 or 6 is switched is compared, and the power supply unit 5 having a high reception level is selected.
[0059]
At this time, if the switch 32 is short-circuited by the control unit 25 and the short-circuit element 4 is selected, the capacitive reactance between the user's finger 14 and the plate-like element 1 increases. Therefore, the frequency characteristic of the VSWR of the plate-like inverted F antenna changes from the state of the graph curve 36 to the graph curve 37. That is, the resonance frequency is reduced to 800 MHz. In this case, the VSWR at 900 MHz is about 5, and the impedance mismatch loss increases. In this case, the PAG is about -17 dBd.
[0060]
Here, in the antenna device according to the embodiment of the present invention, if a finger is detected by the sensor unit 35, the control unit 25 short-circuits the switch 33 and uses the short-circuit element 30 close to the adjacent finger 14 to form a plate-like element. 1 and the ground plane 3 are connected to operate to select the second state, thereby improving the VSWR. By controlling in this way, the resonance frequency (800 MHz) indicated by the graph curve 37 is increased to 880 MHz as indicated by the graph curve 38. In this case, the VSWR at 900 MHz is about 2, and the impedance mismatch loss is reduced. In this case, the PAG is improved to about −15.5 dBd.
[0061]
On the other hand, when the user's finger 14 comes close to the high impedance part 16, the control part 25 short-circuits the switch 34, and the plate-like element 1 and the ground plane 3 are connected using the short-circuiting element 31 close to the close finger 14. Operate to connect and select the third state to improve VSWR. Similarly, the PAG in this case is −15.5 dBd.
[0062]
As described above, in the portable radio antenna apparatus according to the present embodiment, the short-circuit element 4 and the short-circuit elements 30 and 31 are arranged in the middle of the power feeding section 5 or 6, and the sensor section 35 that detects the finger is provided. The higher power supply unit is selected, and then the short-circuit element is selected depending on whether or not the finger is in proximity, thereby improving the VSRW and reducing the amount of PAG degradation when the finger is in proximity. This can be further improved as compared with the first to third embodiments.
[0063]
Note that the size and arrangement configuration of the plate-like element 1 and the short-circuit element to be arranged are not limited to the description of the present embodiment, and a plurality of power feeding units, a plurality of short-circuit elements, and a sensor unit are arranged. The same effect can be obtained if the configuration can change the position of the high impedance portion and the resonance frequency by switching.
[0064]
(Fifth embodiment)
FIG. 10 is a block diagram showing a configuration example of an antenna device for a portable wireless device according to a fifth embodiment of the present invention, where FIG. 10 (a) is a top view, FIG. 10 (b) is a front view, and FIG. c) is a side view. However, the same parts as those in the fourth embodiment in FIG. 7 are denoted by the same reference numerals, and the description thereof is omitted as appropriate. The antenna device for portable wireless devices of this embodiment has a configuration in which the sensor unit is deleted from the configuration of the fourth embodiment described above.
[0065]
Next, the operation of this embodiment will be described. For example, as shown in FIG. 11, when the user's finger 14 is close to the high impedance unit 15, the reception level detection unit 9 performs an operation of selecting the power supply unit 5 or 6 and detecting each level. Thereafter, the reception level detection unit 9 determines the presence or absence of the proximity of the finger based on the detection result, controls the switches 32, 33, and 34, and performs the first, second, or third as in the fourth embodiment. Select the state.
[0066]
When the user's finger 14 is close to the high impedance unit 15 as described above, the reception level detection unit 9 is configured to select the higher reception level as described in the first embodiment. The power supply unit 5 is selected by controlling the switch 7 to the terminal a side. The reception level detection unit 9 determines whether the user's finger 14 is close to the power supply unit 5 side or the power supply unit 6 side because the reception levels of the power supply units 5 and 6 are different. Since it is close to the unit 5 side, the VSWR is improved by short-circuiting the switch 33 and selecting the second state. At this time, the same effect as in the fourth embodiment is obtained, and the PAG is improved to about −15.5 dBd.
[0067]
On the other hand, when the user's finger 14 is close to the high impedance unit 16, the reception level detection unit 9 selects the power supply unit 6 and the third state by the same control as described above. −15.5 dBd.
[0068]
As described above, in the antenna device for a portable wireless device according to the present embodiment, the short-circuit element 4 and the short-circuit elements 30 and 31 are arranged between the power supply units 5 and 6, and the comparison of the reception level of the power supply unit 5 or 6 By detecting the presence / absence and position of proximity, first selecting the power supply unit with the higher reception level, and then selecting the short-circuit element 4, 30 or 31 according to the position of the adjacent finger. VSRW can be improved without arranging a sensor unit that directly detects the PAG, and the amount of PAG degradation when a finger approaches can be significantly suppressed.
[0069]
In addition, the magnitude | size and arrangement | positioning structure of the plate-shaped element 1 and a short circuit element which are arrange | positioned are not restricted to description of this embodiment, A detection part which compares a several power feeding part, a several short circuit element, and a received level is provided. The same effect can be obtained as long as the position of the high impedance portion and the resonance frequency can be changed by switching them.
[0070]
As described above, according to the present embodiment, when the feeding position of the plate-shaped inverted F antenna is selected so that the reception level is the highest, the finger is close to the antenna without detecting the position of the finger. PAG can be improved.
[0071]
In addition, the position of the finger is detected by selecting the position of the conductive member connecting the first plate-shaped member and the second plate-shaped member forming the plate-shaped inverted F antenna so that the reception level becomes the highest. Without any problem, it is possible to improve the PAG when the finger is close to the antenna.
[0072]
In addition, by selecting the feeding position of the plate-like inverted F antenna according to the position of the adjacent finger, the PAG when the finger is close to the antenna can be improved.
[0073]
Further, by selecting the position of the conductive member connecting the first plate-like member and the second plate-like member forming the plate-like inverted F antenna according to the position of the adjacent finger, the case where the finger is close to the antenna PAG can be improved.
[0074]
In addition, the feeding position of the plate-shaped inverted F antenna is selected so that the reception level becomes the highest, and the conductive member that connects the first plate member and the second plate member that forms the plate-shaped inverted F antenna is used. By selecting the position according to the position of the adjacent finger, the PAG when the finger is close to the antenna can be significantly improved.
[0075]
In addition, the feeding position of the plate-shaped inverted F antenna is selected so that the reception level becomes the highest, and the conductive member that connects the first plate member and the second plate member that forms the plate-shaped inverted F antenna is used. By selecting the position so that the reception level is the highest, the PAG when the finger is close to the antenna can be significantly improved without detecting the position of the finger.
[0076]
【The invention's effect】
As described above, according to the present invention, by selecting the feeding position of the plate-like inverted F antenna so that the reception level becomes the highest, the portable radio device or the like can be detected without detecting the position of the user's finger or the like. The PAG when the user's finger or the like is close to the antenna can be improved.
[Brief description of the drawings]
FIG. 1 is a top view, a front view, and a side view showing a configuration example of an antenna device for a portable wireless device according to a first embodiment of the present invention.
FIG. 2 is an explanatory diagram showing a state in which the user holds the portable wireless device shown in FIG.
FIG. 3 is a top view, a front view, and a side view showing a configuration example of an antenna device for a portable wireless device according to a second embodiment of the present invention.
4 is an explanatory diagram showing a state in which a user is holding the portable wireless device shown in FIG.
FIGS. 5A and 5B are a top view, a front view, and a side view showing a configuration example of an antenna device for a portable wireless device according to a third embodiment of the present invention. FIGS.
6 is an explanatory diagram showing a state in which a user is holding the portable wireless device shown in FIG.
FIGS. 7A and 7B are a top view, a front view, and a side view showing a configuration example of an antenna device for a portable wireless device according to a fourth embodiment of the present invention. FIGS.
FIG. 8 is a characteristic diagram showing the amount of frequency fluctuation when the user's finger is close to the high impedance part of the antenna.
FIG. 9 is an explanatory diagram showing a state in which the user holds the portable wireless device shown in FIG.
FIGS. 10A and 10B are a top view, a front view, and a side view showing a configuration example of an antenna device for a portable wireless device according to a fifth embodiment of the present invention.
11 is an explanatory diagram showing a state in which the user holds the portable wireless device shown in FIG. 10 by hand and makes a call.
[Explanation of symbols]
1 Plate element
2 slits
3 Ground plane
4, 17, 18, 30, 31 Short-circuit element
5, 6, 19 Feeder
7, 20, 21, 32, 33, 34 switch
8 Radio circuit part
9 Reception level detector
10, 26 Arithmetic processing section
11, 27 Memory part
12 Portable radio
22, 23, 24, 35 Sensor unit
25 Control unit

Claims

An antenna device having a plate-like inverted F antenna,
A feeder switching means for selecting any one of a plurality of feeders provided at a plurality of locations on the plate-like inverted F antenna;
Position detecting means for detecting the position of a finger in proximity to the antenna device;
A power feeding unit determining means for determining any one of the plurality of power feeding units according to the detected finger position, and selecting the determined power feeding unit by the power feeding unit switching unit;
An antenna device comprising:

An antenna device having a plate-like inverted F antenna,
A first plate member;
A second plate member;
A plurality of conductive members for connecting the first plate-like member and the second plate-like member at a plurality of locations;
Antenna forming means for selecting one of the plurality of conductive members and connecting the first plate-like member and the second plate-like member to form the plate-like inverted F antenna;
Position detecting means for detecting the position of a finger in proximity to the antenna device;
One of the plurality of conductive members is determined according to the detected finger position, and the first plate-shaped member and the second plate-shaped member are determined by the conductive member determined by the antenna forming unit. A conductive member determining means to be connected;
An antenna device comprising:

  An antenna device having a plate-like inverted F antenna,
  A feeder switching means for selecting any one of a plurality of feeders provided at a plurality of locations on the plate-like inverted F antenna;
  A reception level comparing means for comparing the reception levels obtained each time the power feeding unit is switched;
  Position detecting means for detecting the position of a finger in proximity to the antenna device;
  A power feeding unit determining means for determining any one of the plurality of power feeding units according to the detected finger position, and selecting the determined power feeding unit by the power feeding unit switching unit;
  A first plate member;
  A second plate member;
  A plurality of conductive members for connecting the first plate-like member and the second plate-like member at a plurality of locations;
  Antenna forming means for selecting one of the plurality of conductive members and connecting the first plate-like member and the second plate-like member to form the plate-like inverted F antenna;
  One of the plurality of conductive members is determined according to a comparison result of the reception level comparing means, and the first plate member and the second plate member are determined by the conductive member determined by the antenna forming means. Conductive member determining means for connecting
  An antenna device comprising:

An antenna device having a plate-like inverted F antenna,
A feeder switching means for selecting any one of a plurality of feeders provided at a plurality of locations on the plate-like inverted F antenna;
A reception level comparison means for comparing the reception levels obtained each time the power supply unit is switched;
A power supply unit determining unit that determines any one of the plurality of power supply units according to the comparison result, and selects the determined power supply unit by the power supply unit switching unit;
A first plate member;
A second plate member;
A plurality of conductive members for connecting the first plate-like member and the second plate-like member at a plurality of locations;
Antenna forming means for selecting one of the plurality of conductive members and connecting the first plate-like member and the second plate-like member to form the plate-like inverted F antenna;
Position detecting means for detecting the position of a finger in proximity to the antenna device;
One of the plurality of conductive members is determined according to the detected finger position, and the first plate-shaped member and the second plate-shaped member are determined by the conductive member determined by the antenna forming unit. A conductive member determining means to be connected;
An antenna device comprising:

  An antenna device having a plate-like inverted F antenna,
  A feeder switching means for selecting any one of a plurality of feeders provided at a plurality of locations on the plate-like inverted F antenna;
  Position detecting means for detecting the position of a finger in proximity to the antenna device;
  A power feeding unit determining means for determining any one of the plurality of power feeding units according to the detected finger position, and selecting the determined power feeding unit by the power feeding unit switching unit;
  A first plate member;
  A second plate member;
  A plurality of conductive members for connecting the first plate-like member and the second plate-like member at a plurality of locations;
  Antenna forming means for selecting one of the plurality of conductive members and connecting the first plate-like member and the second plate-like member to form the plate-like inverted F antenna;
  One of the plurality of conductive members is determined according to the position of the finger detected by the position detecting means, and the first plate-like member and the second conductive member are determined by the conductive member determined by the antenna forming means. Conductive member determining means for connecting the plate-shaped members;
  An antenna device comprising: