200300619 玖、發明說明 (發明說明應敘明:發明所屬之技術領域、先前技術、內容、實施方式及圖式簡單說明) 1 .發明所屬之技術領域 本發明主要係關於通訊領域上使用之天線,特別係關於 頻率高之通訊領域上適用之小型天線。 2 .先前技術 本發明之天線能在廣泛之通訊領域上使用,特別適用作 爲微波天線,在此領域上,以往之天線有微細天線(micro strip antenna),或者 patch a n ten n a(平面天線)° lit 平面天 線普通係由接地導體板和重疊在此接地導體板上之介電體 板,及重疊在此介電體板上之細長或patch狀之金屬薄板 之供電元件所作成。藉浸蝕作業能容易在印刷底板上製作 放射元件和供電線,藉此作成薄型輕量之天線,進而使用 於攜帶電話等之小型通訊裝置上。 第2 0和第2 1圖係示出此以往之平面天線在放射方向水 平內之指向性。2.45GHz之波束寬係爲60度。 3 .發明內容 此種天線若爲了提高增益,在印刷底板上配置多數之放 射元件,並各別供電時則會有,面積會擴大,及供電損失 增加之問題。即使係高頻,比公分(centime ter)波低之頻率 ,平面天線也會增大,另若爲了獲得高增益(gain),作成 上述那樣之陣列構成時則例如,設置在房屋之情形時外觀 上會變大,另外,其結果在構造之強度上也會產生問題。 本發明之目的在於提供增益高,且小型之通訊用天線, 200300619 另外提供頻率範圍廣,指向性窄之通訊用天線。 達成上述目的之本發明之天線係爲具備由接地導體板, 配置在此接地導體板上之金屬薄板狀之供電元件,距此供 電元件0.0 1〜0 . 2波長程度配置之金屬薄板狀之第1無供 電元件,及距供電元件〇 . 2〜0 . 8波長,最好是0.4〜0 . 6波 長,配置之金屬薄板狀之第2無供電元件所作成之階層構 造體之天線。 藉將供電元件之尺寸和距此供電元件〇 . 〇 1〜〇 . 2波長程 度配置之金屬薄板狀之第1無供電元件之尺寸作成若干不 同,產生只有中心頻率分離之兩個共振狀態,總合之共振 之共振頻寬擴大,從而成爲寬頻之天線。另外,藉距供電 元件0.2〜0.8波長,最好是0.4〜0.6波長,配置之第2無 供電元件,放射波束窄化縮小以提高指向性特性和增益。 因係作成階層構造體,故不會佔用大面積。 階層構造體也可包含距第2無供電元件0.2〜0 . 8波長, 最好是0.4〜0.6波長,配置之金屬薄板狀之第3無供電元 件。藉此第3無供電元件能更改善指向性。 階層構造體含有自第3無供電元件起各距0.2〜0 . 8波長 ,最好是0.4〜0.6波長,配置之金屬薄板狀之無供電元件 ,其第4以後之無供電元件之數係依由接地導體板之大小 決定之波束縮小效果之收斂而定。隨著第4以後之無供電 元件數之增加波束寬雖變窄,但其縮小之效果之程度係成 非線性減小,最終變成再增加無供電元件也無意義。接地 -10- 200300619 導體板愈大,愈能增加無供電元件之數。現實上,係依目 標之縮小效果決定第4以後之無供電元件數。 供電元件和無供電元件之形狀也可係爲細長,圓形或四 角形。 藉具備前方開放之金屬匣以收容階層構造體,能抑制朝 側面放射之電磁波,使朝前放射方向放射之能量反射以提 高增益。 在階層構造體之側面配置電波吸收體俾能吸收射向側面 之電磁波。 另外,以上述之目的,特別是以寬頻和小型化爲主目的 之本發明之天線具備由接地導體板,配置在此接地導體板 上之金屬薄板狀之供電元件,與此供電元件分離設置,或 密接配置之介電體板,及與此介電體板分離設置或密接配 置之金屬薄板狀之無供電元件所作成之階層構造體。 藉介電係數比空氣者大之介電體板之插置,縮短電磁波 之波長,階層構造體之高度能減少一對應於此縮短之波長 之份,而能助於小型化。另外,產生供電元件之共振和供 電元件與介電體板間之共振之多數之共振狀態,從而成爲 總合上之共振之共振頻寬擴大之寬頻天線。這種情形,供 電元件和無供電元件之形狀也可係爲細長,圓形或四角形 。階層構造體係被收容於前方開放之金屬匣內俾抑制放射 至側面之電磁波,並使朝前方放射之能量反射而能提高增 益。另外,階層構造體之側面也可配置電波吸收體。 -11- 200300619 另外,本發明之天線係由接地導體板,金屬薄板狀之供 電元件,及金屬薄板狀之無供電元件所作成之階層構造體 之中心軸上裝設導體或絕緣體材料之支撐棒,或在階層構 造體之中心軸以外所與之位置上裝設絕緣體材料之支撐棒 而與階層構造體成一體固定。另外,也可在階層構造體之 供電元件和無供電元件之間配置低介電係數之間隔件 (spacer)而與階層構造體作成一體。 4 .實施方式 # 參照第1圖,階層薄板天線具備由接地導體板1,配置 在此接地導體板上之金屬薄板狀之供電元件2,距此供電 元件2 0 . 1波長配置之金屬薄板狀之第1無供電元件3,及 距此供電元件2 0 . 5波長配置之金屬薄板狀之第2無供電 元件4所作成之階層構造體。 藉將供電元件2之尺寸和距0. 1波長配置之第1無供電 元件3之尺寸作成若干不同以產生只有共振頻率分離之兩 | 個共振狀態,從而擴大總合上之共振之共振頻率。此間隔 係爲0.0 1〜0.2波長程度之長度之情形之頻寬擴大效果已 藉實驗確認,另外,也有助於減少階層構造體之高度。這 點,藉比較表示只有供電元件2之反射特性之第2圖和表 示加裝第i無供電元件3之情形之反射特性之第3圖,即 可明白。 另外,藉距供電元件2 0.5波長配置之第2無供電元件4 ,縮小放射波束以改善指向性特性和增益。如第4及第5 200300619 圖所示,2.45GHz在放射方向之水平面和垂直面內之波束 寬皆爲4 4度,相對於通常之平面天線在放射方向之水平面 內之波束寬爲6 0度有顯著之改善。已藉實驗確認此0 . 5波 長之間隔對波束寬之收束係最具效果。 階層構造體含有距第2無供電元件4 0 . 5波長配置之金 屬薄板狀之第3無供電元件5之實施例係示於第6圖。看 看藉此第3無供電元件5更加改善指向特性之情形。如第 7及第8圖所示,2.45GHz在放射方向水平面內和垂直面 內之波束寬皆成爲3 7.5度,相較於第1圖之天線之4 4度 更爲改善 ° 爲了更縮小波束也可在距第3無供電元件0 . 5波長處配 置金屬薄板狀之第4以後之無供電元件,但接地導體板之 大小自有限制,超過此限度即看不出對指向特性之改善。 這種情形,供電元件和無供電元件之形狀也是作成四角 形,但也可係爲細長或圓形。 參照第9圖(a ),階層構造體係被收容於前方開放之金屬 匣。金屬匣6係爲由底面之接地導體板1和側面之金屬板 6a作成之構造。7係爲供電用連接器(connector)。藉此金 屬匣抑制朝側向放射之電磁波,使朝前向放射之能量反射 而能提高增益。如第1 〇和第1 1圖所示2.4 5 G Η z在放射方 向水平內之波束寬係爲3 5度,垂直面內之波束寬係爲4 3 度,相較於第6圖之天線放射型樣(p a 11 e r η ),側向,後向 之輻射係顯著地被抑制,另外水平面內之波束寬3 5度比第 -13- 200300619 6圖之天線之3 7 . 5度波束更爲縮小,因此也改善了此縮小 部份之增益。 下面將說明收容階層構造體之金屬匣。參照第9圖(a), 階層構造體底面之接地導體板1之形狀除了矩形外,也可 作成圓形,多角形等各種形狀。另外,接地導體板之形狀 也能作成爲平面或曲面。金屬板6 a係對階層構造體底面之 接地導體板1之延長方向傾斜成一角度θ ( Θ係在0 ° <θ S 9 0 ° 之範圍),其形狀能作成爲平面或曲面。藉調整此金屬板 6 a之高度及傾斜角度,能得出所要之指向特性。另外,階 層構造體底面之接地導體板1和金屬板6a係藉絞鏈(hinge) 構造,蛇腹構造,螺栓接合(bolt joint)構造等各種接合方 法接合,從而可改變傾斜角度Θ,能容易變更指向特性。 另外,藉滑件導座(s 1 i d e g u i d e ),滑道(s 1 i d e w a y ),滑軌 (s 1 i d e r a i 1)之各種滑動構造使金屬板6 a滑動,可改變金屬 板6 a之高度,進而能容易變更指向特性。金屬匣之材質並 無特別限定,但最好是體積電阻係數在1.〇χ1〇_5[Ω·6ιιι]以 下之導體體之金屬或金屬複合材料。 第9圖(b)係爲示出金屬匣1之實施例之斜視圖,金屬匣 係呈前方開放之四角錐台之形狀,鄰接之金屬板6a之緣部 全部接合。金屬板6 a之傾斜角度Θ (參照第9圖(d))對階層 構造體底面之接地導體板之延長方向係在〇 ° < Θ S 9 0 °之範 圍內。金屬板之形狀係爲平面或也可係爲曲面。另外,收 容階層構造體之底面之接地導體板除了矩形外也可作成爲 -14- 200300619 圓形,多角形等之各種形狀。另外,接地導體板之形狀能 作成平面或曲面。第9圖(c )係爲示出金屬板6 a間之緣部 未接合之形狀之實施例之斜視圖。此時,鄰接之金屬板6 a 相互全部接合也好,或不接合也好,指向特性不會改變。 本實施例之金屬板6 a係爲四角形,金屬板6 a之傾斜角度 θ(參照第9圖(d))對階層構造體底面之接地導體板之延長 方向係在〇°<θ$90°之範圍。金屬板6a之長度和供電元件 之長度之比最好係爲1 : 1以上。因不必接合金屬板6 a,故 製造容易,從而能降低製造成本。藉調整此金屬板6 a之高 度,及傾斜角度Θ,能得出所要之指向特性。另外,藉將 金屬板6 a之高度,及傾斜角度Θ作成可變之構造,能容易 地變更指向特性。 如第9圖(d)所示,藉調整金屬板之角度,能改變所要之 指向特性。 金屬板6 a之所需張數係依所要之特性而定,但也與階層 構造體底面之接地導體板形狀有關。在不必要放射電磁波 之方向上藉設置金屬板6 a能抑制電磁波之放射。 也可在階層構造體之側面配置電磁波吸收體,以吸收朝 側向放射之電磁波。電磁波吸收體能使用含有肥粒鐵 (ferrite)等之磁性體之樹脂膜等。 特別是以寬頻,小型,高增益化爲目的之本發明之階層 薄板天線係如第1 2圖所示,具有由接地導體板1,配置在 此接地導體板上之金屬薄板狀之供電元件2,與此供電元 200300619 件2分離配置之比較厚之介電體板8,及密接配置於介電 體板8上之金屬板狀之無供電元件4所作成之階層構造體 。第1 2圖示出比較厚之介電體板8係與供電元件2分離配 置,但也可密接於供電元件。介電體板8與供電元件2隔 適當距離配置,能擴大頻寬。另外,由於設計上之關係也 有將無供電元件4與介電體板8分離配置。 藉插置介電體板8,電磁波之波長比在空氣中者變短, 階層構造體之高度能降低一相當於此短小之部份,進而有 助於小型化。另外,產生供電元件之共振和供電元件與介 電體板間之共振之多數共振狀態,從而擴大總合之共振之 共振頻寬。第1 3和第1 4圖係示出其特性。這裡,介電體 板8係距供電元件2約0.5 c m配置,2.4 5 G Η z在水平面內 之波束寬係爲38.5度,垂直面內之波束寬係爲71度。另 外,第1 5和第1 6圖係示出被收容於前方開放之金屬匣內 之情形之天線特性。自此第1 5和第1 6圖可明白,朝側面 和後方之輻射係顯著地被抑制。再者,2.4 5 G Η ζ在水平面 內之波束寬係爲45度垂直面內之波束寬係爲50度。 第1 7圖所示之本發明之第4實施形態之天線係在由接地 導體板1,供電元件2及無供電元件3,4,5作成之階層 構造體之周緣部上裝設4根之絕緣支撐棒9而與階層構造 體成一體固定。第1 8圖所示之本發明之第5實施形態之天 線係爲在階層構造體之中心軸上裝設導電體支撐棒1 〇而 與階層構造體成一體固定。第1 9圖所示之本發明之第6 -16- 200300619 實施形態係爲在接地導體板1和供電元件2和無供電元件 3,4,5之間配置低介電係數之間隔件1 1而與階層構造體 成一體者。此第6實施形態另如第1 7或第1 8圖所示,也 能裝設絕緣體支撐棒9或導電體支撐棒1 0而固定階層構造 體。另外,例如,如第9圖所示,也可將上述之那些階層 構造體收容於金屬匣內。 從上述可明白,藉本發明除了能提高天線之增益外,另 對小型化也有效。另外,能擴大頻寬,窄化波束寬,從而 能提高指向性。 5 .圖式簡單說明 第1圖係爲本發明之第1實施形態之天線之斜視圖。 第2圖係爲只有供電元件之天線之反射特性圖。 第3圖係爲有供電元件和無供電元件之天線之反射特性 圖。 第4圖係爲本發明之第1實施形態之天線之指向特性圖。 第5圖係爲本發明之第1實施形態之天線之指向特性之 展開圖。 第6圖係爲本發明之第2實施形態之天線之斜視圖。 第7圖係爲本發明之第2實施形態之天線之指向特性圖。 第8圖係爲本發明之第2實施形態之天線之指向特性之 展開圖。 第9圖(a)係爲示出將本發明之第2實施形態之天線收容 於金屬匣之情況之側面斷面圖,(b),(〇係爲示出金屬匣之 200300619 另外實施例之斜視圖,(d)係爲示出金屬板之角度變化和指 向特性變化圖。 第1 〇圖係爲第9圖(a)之天線之指向特性圖。 第1 1圖係爲第9圖(a)之天線之指向特性之展開圖。 第1 2圖係爲本發明之第3實施形態之天線之斜視圖。 第1 3圖係爲本發明之第3實施形態之天線之指向特性圖。 第1 4圖係爲本發明之第3實施形態之天線之指向特性之 展開圖。 鲁 第1 5圖係爲收容於金屬匣內之本發明之第3實施形態之 天線之指向特性圖。 第1 6圖係爲收容於金屬匣內之本發明之第3實施形態之 天線之指向特性之展開圖。 第1 7圖係爲示出本發明之第4實施形態之天線之側面斷 面圖。 第1 8圖係爲示出本發明之第5實施形態之天線之側面斷 | 面圖。 第1 9圖係爲示出本發明之第6實施形態之天線之側面斷 面圖。 第2 0圖係爲以往之平面天線之指向特性圖。 第2 1圖係爲以往之平面天線之指向特性之展開圖。 符號說明 1 接地導體板 2 供電元件 -18- 200300619 3 Μ 供 電 元 件 4 te ^ \ NN 供 電 元 件 5 M j \ \\ 供 電 元 件 6 金 屬 匣 6 a 金 屬 板 7 供 電 用 連 接 器 8 介 電 體 板 9 絕 緣 體 支 撐 棒 10 導 電 體 支 撐 棒 11 低 介 電 係 數 間隔件200300619 发明 Description of the invention (The description of the invention should state: the technical field, prior art, content, implementation and drawings of the invention are briefly explained) 1. The technical field to which the invention belongs The present invention relates to antennas used in the field of communication, In particular, it relates to small antennas suitable for high-frequency communication applications. 2. The prior art The antenna of the present invention can be used in a wide range of communication fields, and is particularly suitable for use as a microwave antenna. In this field, conventional antennas have a micro strip antenna, or a patch antenna (planar antenna) ° The lit planar antenna is generally made of a grounded conductor plate and a dielectric plate superposed on the grounded conductor plate, and a power supply element of an elongated or patch-shaped metal thin plate superposed on the dielectric plate. By etching, it is possible to easily make a radiation element and a power supply line on a printed substrate, thereby making a thin and lightweight antenna, and then used for small communication devices such as mobile phones. Figures 20 and 21 show the directivity of the conventional planar antenna in the level of the radiation direction. The beam width at 2.45GHz is 60 degrees. 3. SUMMARY OF THE INVENTION In order to increase the gain of such an antenna, a large number of radiating elements are arranged on a printed substrate, and there will be problems when power is supplied separately, the area will increase, and power loss will increase. Even if it is a high frequency, the plane antenna will increase at a frequency lower than the centime ter wave. In addition, in order to obtain a high gain, when the above-mentioned array structure is made, for example, the appearance when it is installed in a house It will become larger, and as a result, there will be problems in the strength of the structure. The object of the present invention is to provide a small-sized communication antenna with high gain. 200300619 In addition, it provides a communication antenna with a wide frequency range and narrow directivity. The antenna of the present invention which achieves the above-mentioned object is a metal sheet-shaped power supply element provided with a grounded conductor plate and arranged on the grounded conductor plate. 1 an antenna without a power supply element, and a layered structure made of a metal sheet-shaped second non-power-supply element with a wavelength of 0.2 to 0.8, preferably 0.4 to 0.6 wavelength, from the power-supply element. By making the size of the power supply element and the size of the metal thin plate-shaped first non-power supply element with a distance of 〇. 〇1 ~ 〇. 2 from the power supply element, the size of the first non-power supply element is made different. The resonant bandwidth of the combined resonance is expanded, thus becoming a wide-band antenna. In addition, the distance from the power supply element is 0.2 to 0.8 wavelength, preferably 0.4 to 0.6 wavelength. The second non-power supply element is arranged, and the radiation beam is narrowed to reduce directivity characteristics and gain. Because it is a hierarchical structure, it does not occupy a large area. The layered structure may include a third thin non-powered element in the form of a thin metal plate having a wavelength of 0.2 to 0.8, preferably 0.4 to 0.6 wavelengths from the second non-powered element. This improves the directivity of the third non-powered component. The layered structure contains 0.2 to 0.8 wavelengths, preferably 0.4 to 0.6 wavelengths, from the third non-power-supply element. The metal thin plate-shaped non-power-supply elements are arranged, and the number of the fourth and subsequent non-power-supply elements depends on The convergence of the beam reduction effect is determined by the size of the grounded conductor plate. With the increase of the number of non-powered components after the fourth, although the beam width becomes narrower, the degree of its reduction effect is a non-linear decrease, and it eventually becomes meaningless to add another non-powered component. Grounding -10- 200300619 The larger the conductor plate, the more it can increase the number of non-powered components. In reality, the number of unpowered components after the 4th is determined by the reduction effect of the target. The shape of the power-supplying element and the non-power-supplying element can also be slender, circular or quadrangular. A metal box with an open front is used to house the hierarchical structure, which can suppress the electromagnetic waves radiating to the side, and reflect the energy radiated in the forward radiation direction to increase the gain. An electromagnetic wave absorber is arranged on the side surface of the hierarchical structure, and can absorb electromagnetic waves directed to the side surface. In addition, the antenna of the present invention for the above-mentioned purpose, especially for the purpose of broadband and miniaturization, is provided with a grounding conductor plate, and a metal thin plate-shaped power feeding element arranged on the grounding conductor plate, and is provided separately from the power feeding element. Or a densely arranged dielectric body plate, and a layered structure made of a metal thin plate-like non-power-supply component provided separately from or tightly arranged with the dielectric body plate. By inserting a dielectric plate having a larger dielectric constant than air, the wavelength of electromagnetic waves can be shortened, and the height of the hierarchical structure can be reduced by a portion corresponding to the shortened wavelength, which can help miniaturization. In addition, many resonance states of the resonance of the power supply element and the resonance between the power supply element and the dielectric plate are generated, thereby becoming a wide-band antenna in which the resonant frequency of the combined resonance is enlarged. In this case, the shape of the power-supplying element and the non-power-supplying element can also be slender, circular or quadrangular. The hierarchical structure system is housed in a metal box opened in the front to suppress electromagnetic waves radiated to the side and reflect the energy radiated forward to increase the gain. A radio wave absorber may be disposed on the side of the hierarchical structure. -11- 200300619 In addition, the antenna of the present invention is a support rod of a conductor or insulator material on the central axis of a hierarchical structure made of a grounded conductor plate, a metal sheet-like power supply element, and a metal sheet-like no power supply element. Or, a support rod of an insulator material is installed at a position other than the central axis of the hierarchical structure to be integrated with the hierarchical structure. In addition, a spacer having a low dielectric constant may be disposed between the power-supplying element and the non-power-supplying element of the hierarchical structure to be integrated with the hierarchical structure. 4. EMBODIMENT # Referring to FIG. 1, a hierarchical thin plate antenna is provided with a grounded conductive plate 1 and a metal thin plate-shaped power supply element 2 arranged on the grounded conductive plate. The metal thin plate shape is arranged at a wavelength of 20.1 from the power supply element. A layered structure made of the first non-power-supplying element 3 and a metal thin plate-shaped second non-power-supplying element 4 arranged at a wavelength of 0.5 from the power-supplying element. By making the size of the power-supplying element 2 and the size of the first non-power-supplying element 3 at a distance of 0.1 wavelengths different from each other to generate two resonance states separated only by the resonance frequency, the total resonance resonance frequency is enlarged. The effect of widening the bandwidth in the case of a length of about 0.01 to 0.2 wavelength has been confirmed through experiments, and it also helps to reduce the height of the hierarchical structure. This point can be understood by comparing the second graph showing the reflection characteristics of only the power supply element 2 and the third graph showing the reflection characteristics when the i-th power supply element 3 is not installed. In addition, the second non-power-supplying element 4 with a 0.5-wavelength configuration from the power-supplying element 2 is used to reduce the radiation beam to improve the directivity characteristics and gain. As shown in Figures 4 and 5, 200300619, the beam width of 2.45GHz in the horizontal and vertical planes of the radiation direction is 44 degrees, and the beam width in the horizontal plane of the radiation direction is 60 degrees relative to a normal planar antenna. There are significant improvements. Experiments have confirmed that this 0.5-wavelength interval is most effective for beam-width converging systems. An embodiment in which the layered structure includes a metal thin plate-shaped third non-power-supplying element 5 arranged at a wavelength of 40. 5 from the second non-power-supplying element is shown in FIG. It will be seen that the third non-power-supply element 5 further improves the directional characteristics. As shown in Figures 7 and 8, the beam width of 2.45 GHz in the horizontal and vertical planes of the radiation direction is 3 7.5 degrees, which is better than the 4 4 degrees of the antenna in Figure 1. ° In order to reduce the beam size It is also possible to arrange the metal plate-like fourth and subsequent non-powered components at a wavelength of 0.5 from the third non-powered component, but the size of the grounding conductor plate has its own limit, and beyond this limit, no improvement in directional characteristics is seen. In this case, the shapes of the power-supplying element and the non-power-supplying element are also quadrangular, but they may be slender or circular. Referring to FIG. 9 (a), the hierarchical structure system is housed in a metal box opened in the front. The metal box 6 has a structure made of a ground conductor plate 1 on the bottom surface and a metal plate 6a on the side surface. The 7 series is a connector for power supply. In this way, the metal box suppresses the electromagnetic waves radiating sideways, reflects the energy radiating forward, and can increase the gain. As shown in Fig. 10 and Fig. 11, the beam width of 2.4 5 G Η z in the horizontal direction of the radiation direction is 35 degrees, and the beam width in the vertical plane is 43 degrees, compared with the antenna in Fig. 6 Radial pattern (pa 11 er η), the lateral and backward radiation is significantly suppressed, and the beam width in the horizontal plane is 35 degrees, which is more than the 37.5 degree beam of the antenna in Figure -13- 200300619 6 In order to reduce, the gain of this reduced part is also improved. The metal case containing the hierarchical structure will be described below. Referring to Fig. 9 (a), the shape of the ground conductor plate 1 on the bottom surface of the hierarchical structure may be various shapes such as a circle, a polygon, and the like. In addition, the shape of the ground conductor plate can be made flat or curved. The metal plate 6a is inclined at an angle θ to the extension direction of the ground conductor plate 1 on the bottom surface of the hierarchical structure (θ is in the range of 0 ° < θ S 9 0 °), and its shape can be made flat or curved. By adjusting the height and inclination angle of the metal plate 6a, the desired directional characteristics can be obtained. In addition, the ground conductor plate 1 and the metal plate 6a on the bottom surface of the hierarchical structure are joined by various joining methods such as a hinge structure, a bellows structure, and a bolt joint structure, so that the inclination angle Θ can be changed and can be easily changed. Pointing characteristics. In addition, by using various sliding structures of the slide guide (s 1 ideguide), the chute (s 1 ideway), and the slide rail (s 1 iderai 1) to slide the metal plate 6a, the height of the metal plate 6a can be changed, and further It is easy to change directional characteristics. The material of the metal box is not particularly limited, but it is preferably a metal or metal composite material with a conductor having a volume resistivity of 1.0 × 10-5 [Ω · 6ιιι]. Fig. 9 (b) is a perspective view showing an embodiment of the metal box 1. The metal box is in the shape of a quadrangular pyramid with an open front, and the edges of adjacent metal plates 6a are all joined. The inclination angle Θ of the metal plate 6a (refer to FIG. 9 (d)) extends to the ground conductor plate on the bottom surface of the hierarchical structure within a range of 0 ° < Θ S 9 0 °. The shape of the metal plate is flat or curved. In addition, the ground conductor plate on the bottom surface of the housing structure can also be made into various shapes such as -14-200300619 circular, polygonal, etc. in addition to rectangular. In addition, the shape of the ground conductor plate can be made flat or curved. Fig. 9 (c) is a perspective view showing an embodiment in which the edge portions between the metal plates 6a are not joined. At this time, the adjacent metal plates 6 a may be all joined to each other, or they may not be joined, and the directivity characteristics are not changed. The metal plate 6a of this embodiment is a quadrangle, and the inclination angle θ of the metal plate 6a (refer to FIG. 9 (d)) to the ground conductor plate on the bottom surface of the layered structure is extended to 0 ° < θ $ 90 ° Range. The ratio of the length of the metal plate 6a to the length of the power supply element is preferably 1: 1 or more. Since it is not necessary to join the metal plate 6a, the manufacturing is easy, and the manufacturing cost can be reduced. By adjusting the height of the metal plate 6 a and the inclination angle Θ, the desired directional characteristics can be obtained. In addition, by changing the height of the metal plate 6a and the inclination angle?, The directional characteristics can be easily changed. As shown in Figure 9 (d), by adjusting the angle of the metal plate, the desired directional characteristics can be changed. The required number of sheets of the metal plate 6a depends on the desired characteristics, but is also related to the shape of the ground conductor plate on the bottom surface of the hierarchical structure. By providing the metal plate 6a in a direction in which electromagnetic waves are not necessarily emitted, the radiation of electromagnetic waves can be suppressed. An electromagnetic wave absorber may be disposed on the side of the hierarchical structure to absorb electromagnetic waves radiating sideways. As the electromagnetic wave absorber, a resin film or the like containing a magnetic body such as ferrite can be used. In particular, the hierarchical thin-plate antenna of the present invention for the purpose of wideband, small size, and high gain is shown in FIG. 12 and has a ground conductor plate 1 and a metal thin plate-shaped power supply element 2 arranged on the ground conductor plate. This layered structure is made of a relatively thick dielectric plate 8 arranged separately from this power supply element 200300619 and 2 and a metal plate-like non-power-supplying element 4 closely arranged on the dielectric plate 8. Figures 12 and 12 show that the relatively thick dielectric plate 8 is arranged separately from the power supply element 2, but may be closely attached to the power supply element. The dielectric plate 8 and the power supply element 2 are arranged at an appropriate distance, so that the bandwidth can be increased. In addition, the non-power-supply element 4 and the dielectric plate 8 are also arranged separately due to the design. By inserting the dielectric plate 8, the wavelength of the electromagnetic wave becomes shorter than that in the air, and the height of the layered structure can be reduced by a portion corresponding to this short, thereby contributing to miniaturization. In addition, many resonance states of the resonance of the power supply element and the resonance between the power supply element and the dielectric plate are generated, thereby expanding the total resonance frequency of the resonance. Figures 13 and 14 show their characteristics. Here, the dielectric plate 8 is arranged about 0.5 cm from the power supply element 2, the beam width of 2.4 5 G Η z in the horizontal plane is 38.5 degrees, and the beam width in the vertical plane is 71 degrees. In addition, Figs. 15 and 16 show antenna characteristics when they are housed in a metal box opened in the front. It can be understood from Figs. 15 and 16 that the radiation system to the side and rear is significantly suppressed. Furthermore, the beam width of 2.4 5 G Η ζ in the horizontal plane is 45 degrees and the beam width in the vertical plane is 50 degrees. The antenna according to the fourth embodiment of the present invention shown in FIG. 17 is a four-layered peripheral structure of a hierarchical structure made of a grounded conductor plate 1, a power-supplying element 2, and a non-power-supplying element 3, 4, and 5. The insulating support rod 9 is fixed integrally with the hierarchical structure. The antenna of the fifth embodiment of the present invention shown in Fig. 18 is a conductor supporting rod 10 attached to the central axis of the hierarchical structure and integrally fixed with the hierarchical structure. The sixth embodiment of the present invention as shown in Fig. 19 is a 16-16-200300619 embodiment in which a low-dielectric-constant spacer 1 is arranged between the ground conductor plate 1 and the power-supply element 2 and the non-power-supply element 3, 4, 5 And one with the stratum structure. In the sixth embodiment, as shown in FIG. 17 or FIG. 18, an insulator support rod 9 or a conductor support rod 10 can be installed to fix the hierarchical structure. In addition, for example, as shown in Fig. 9, the above-mentioned hierarchical structures may be housed in a metal case. As can be understood from the above, in addition to improving the antenna gain, the present invention is also effective for miniaturization. In addition, the bandwidth can be increased and the beam width can be narrowed to improve the directivity. 5. Brief Description of Drawings Figure 1 is a perspective view of an antenna according to a first embodiment of the present invention. Fig. 2 is a reflection characteristic diagram of an antenna having only a power supply element. Fig. 3 is a reflection characteristic diagram of an antenna with and without a power supply element. Fig. 4 is a directional characteristic diagram of the antenna according to the first embodiment of the present invention. Fig. 5 is a developed view of the directivity characteristics of the antenna according to the first embodiment of the present invention. Fig. 6 is a perspective view of an antenna according to a second embodiment of the present invention. Fig. 7 is a directional characteristic diagram of an antenna according to a second embodiment of the present invention. Fig. 8 is a developed view of the directivity characteristics of the antenna according to the second embodiment of the present invention. Fig. 9 (a) is a side cross-sectional view showing a case where the antenna of the second embodiment of the present invention is housed in a metal box, (b), (0 is a 200300619 showing a metal box of another embodiment A perspective view, (d) is a graph showing a change in the angle and a directional characteristic of a metal plate. Fig. 10 is a directional characteristic diagram of the antenna of Fig. 9 (a). Fig. 11 is a graph of Fig. 9 ( a) Expansion view of the antenna's directional characteristics. Figures 12 and 12 are perspective views of the antenna of the third embodiment of the present invention. Figure 13 is of the characteristics of the antenna of the third embodiment of the present invention. Figure 14 is a development view of the directional characteristics of the antenna of the third embodiment of the present invention. Figure 15 is a view of the directional characteristics of the antenna of the third embodiment of the present invention housed in a metal box. Fig. 16 is a development view of the directional characteristics of the antenna of the third embodiment of the present invention housed in a metal case. Fig. 17 is a side sectional view of the antenna of the fourth embodiment of the present invention. Fig. 18 is a side cross-sectional view showing a fifth embodiment of the antenna of the present invention. Fig. 20 is a side sectional view of an antenna according to a sixth embodiment of the present invention. Fig. 20 is a directional characteristic diagram of a conventional planar antenna. Fig. 21 is an expanded view of a directional characteristic of a conventional planar antenna. DESCRIPTION OF SYMBOLS 1 Ground conductor plate 2 Power supply element-18- 200300619 3 Μ Power supply element 4 te ^ \ NN Power supply element 5 M j \ \\ Power supply element 6 Metal box 6 a Metal plate 7 Power supply connector 8 Dielectric body plate 9 Insulator support rod 10 Conductor support rod 11 Low dielectric constant spacer
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