TW200414603A - An inverted-F antenna - Google Patents
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- TW200414603A TW200414603A TW92101916A TW92101916A TW200414603A TW 200414603 A TW200414603 A TW 200414603A TW 92101916 A TW92101916 A TW 92101916A TW 92101916 A TW92101916 A TW 92101916A TW 200414603 A TW200414603 A TW 200414603A
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- 239000002184 metal Substances 0.000 claims abstract description 51
- 229910052751 metal Inorganic materials 0.000 claims abstract description 51
- 239000004020 conductor Substances 0.000 claims description 7
- 238000005516 engineering process Methods 0.000 claims description 5
- 238000005530 etching Methods 0.000 claims description 2
- 238000005096 rolling process Methods 0.000 claims description 2
- 238000004891 communication Methods 0.000 abstract description 7
- 230000005855 radiation Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- PCHJSUWPFVWCPO-UHFFFAOYSA-N gold Chemical compound [Au] PCHJSUWPFVWCPO-UHFFFAOYSA-N 0.000 description 4
- 239000010931 gold Substances 0.000 description 4
- 229910052737 gold Inorganic materials 0.000 description 4
- 102100025490 Slit homolog 1 protein Human genes 0.000 description 2
- 101710123186 Slit homolog 1 protein Proteins 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 230000009977 dual effect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000758 substrate Substances 0.000 description 1
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Abstract
Description
200414603 五、發明說明（1) 【發明所屬之技術領域】 本發明係有關於一種倒F形天線（i n v e r t e d - F a n t e η n a )，特別是應用在無線通訊產品上的天線。 【先前技術】 隨著無線通訊的蓬勃發展，各式的通訊產品與技術如 雨後春筍般的出現，也因此無線通訊產品逐漸成為人類生 活中的一部分。而由於無線通訊產品其可擺放天線的空間 都相當狹小，尤其是須要置放於產品機殼内部的内藏式天 線，因此天線的尺寸與性能便成為影響產品好壞的重要關 鍵之一。 倒F形天線是目前常被用於當作内藏式天線的一種設 計，例如内藏於手機、個人數位助理（P D A， p e r s ο n a 1 digital assistant)、筆記型電腦等產品上。而目前習知 應用於無線通訊產品的倒F形天線主要可分為兩種：一種 是將天線設置在系統的接地面正上方並佔據了一定大小的 接地面空間（如中華民國專利第1 5 7 1 2 7號，專利名稱為π雙 頻倒F形平板天線及輻射金屬片”）；另一種則是置放於系 統接地面的上方邊緣處，並距離接地面上緣一固定的高度 (如中華民國專利第1 6 0 9 5 4號，專利名稱為π雙頻倒F型天 線π )，而此類天線的高度通常較大，因此在應用於内藏式200414603 V. Description of the invention (1) [Technical field to which the invention belongs] The present invention relates to an inverted-F antenna (i n v e r t e d-F a n t e η n a), especially an antenna applied to a wireless communication product. [Previous Technology] With the rapid development of wireless communication, various communication products and technologies have sprung up, and therefore wireless communication products have gradually become a part of human life. And because wireless communication products have a very small space for placing antennas, especially the built-in antennas that need to be placed inside the product casing, the size and performance of the antennas have become one of the most important factors affecting the quality of the product. Inverted F antenna is a design that is often used as a built-in antenna. For example, it is built into mobile phones, personal digital assistants (PDA, digital assistants), notebook computers and other products. The currently known inverted F antennas used in wireless communication products can be divided into two types: one is to place the antenna directly above the ground plane of the system and occupy a certain amount of ground plane space (such as the Republic of China Patent No. 1 5 No. 7 1 2 No. 7, the patent name is π dual-frequency inverted F-shaped flat panel antenna and radiating metal sheet "); the other is placed on the upper edge of the ground plane of the system and a fixed height from the edge of the ground plane ( For example, the Republic of China Patent No. 16 0 954, the patent name is π dual-frequency inverted F-type antenna π), and the height of this type of antenna is usually large, so it is used in built-in
200414603200414603
五、發明說明（2) 天線時，常會佔據產品機殼内較大的空間。為解決此一問 題，在本發明中我們提出一種倒F形天線的創新設計，不 僅可滿足GSM( 8 9 0 -9 6 0 MHz)及DCS( 1 7 1 0 - 1 8 8 0 MHz)雙頻帶 操作，且其具有非常低姿勢（8 mm高度）的優點，特別適合 當作内藏式天線，達成美化產品外觀的目的。 【内容】 如上所述，本發明之目的在於提供一種倒F形天線的 創新設計。本發明天線包含：一輻射金屬臂，由一個具有 至少一狹縫的輻射金屬片捲成一柱狀結構而形成，該狹縫 由該輻射金屬片之一邊緣延伸至該輻射金屬片之内部，使 該輻射金屬片形成一較長及一較短之電流路徑，分別用於 產生該天線之第一（低頻）及第二（高頻）操作模態；一接地 面，包含一短路點及一接地點；一短路金屬線，具有一饋 入點，且該短路金屬線一端連接至該輻射金屬臂，另一端 則連接至該接地面之短路點；及一饋入同軸線，用以傳輸 訊號，該同軸線具有一中心導線及一外層接地導體，該中 心導線連接至該短路金屬線之饋入點，而該外層接地導體 則連接至該接地面之接地點。在本項設計中，我們可以藉 由調整該狹縫延伸的路徑，改變該較長及該較短之電流路 徑，以得到適當的共振頻率；調整該短路金屬線上饋入點 及該接地面上短路點的位置，得到良好的阻抗匹配。由以 上特性，我們即可以輕易設計出適用於GSM及DCS雙頻帶操5. Description of the invention (2) When the antenna is used, it often takes up a large space in the product case. In order to solve this problem, in the present invention we propose an innovative design of an inverted-F antenna, which can not only meet the dual requirements of GSM (8 9 0-9 6 0 MHz) and DCS (1 7 1 0-1 8 8 0 MHz) Frequency band operation, and its advantages of very low posture (8 mm height), especially suitable as a built-in antenna, to achieve the purpose of beautifying the appearance of the product. [Content] As mentioned above, the object of the present invention is to provide an innovative design of an inverted-F antenna. The antenna of the present invention includes: a radiating metal arm formed by rolling a radiating metal sheet with at least one slit into a columnar structure, the slit extending from one edge of the radiating metal sheet to the inside of the radiating metal sheet, so that The radiating metal sheet forms a longer and a shorter current path for generating the first (low-frequency) and second (high-frequency) operating modes of the antenna, respectively; a ground plane including a short-circuit point and a connection Place; a short-circuited metal wire having a feed-in point, and one end of the short-circuited metal wire is connected to the radiating metal arm, and the other end is connected to the short-circuited point of the ground plane; and a feed-in coaxial wire is used to transmit signals, The coaxial line has a center wire and an outer ground conductor, the center wire is connected to the feeding point of the short-circuited metal wire, and the outer ground conductor is connected to the ground point of the ground plane. In this design, we can change the longer and shorter current paths by adjusting the path that the slit extends to get the proper resonance frequency; adjust the feed point on the short-circuit metal line and the ground plane The position of the short-circuit point is well matched. With the above characteristics, we can easily design a dual-band operation suitable for GSM and DCS.
200414603 五、發明說明（3) 作的天線。 【實施方式】 參考第卜3圖，本發明之倒F形天線一實施例1包含： 一輻射金屬臂1 0，由一個具有至少一狹縫1 1 3的輻射金屬 片1 1捲成一柱狀結構而形成；一接地面1 3，包含一短路點 1 3 1及一接地點1 3 2，該接地面1 3可以為單一金屬片或以印 刷技術形成於一微波介質基板上；一短路金屬線1 2為一倒 L形，具有一饋入點1 2 1，且該短路金屬線1 2 —端連接至該 輻射金屬臂1 0，另一端則連接至該接地面1 3之短路點 1 3 1 ;及一饋入同軸線1 4，用以傳輸訊號，該同軸線1 4具 有一中心導線1 4 1及一外層接地導體1 4 2，該中心導線1 4 1 連接至該短路金屬線1 2之饋入點1 2 1，而該外層接地導體 1 4 2則連接至該接地面1 3之接地點1 3 1。在本項設計中，如 第3圖所示，該狹縫1 1 3由該輻射金屬片1 1之一邊緣延伸至 該輻射金屬片1 1之内部，使該輻射金屬片1 1被大致分成一 較長之子輻射金屬片1 1 1及一較短之子輻射金屬片11 2，而 該較長之子輻射金屬片11 1上之較長電流路徑1 6及該較短 之子輻射金屬片1 1 2上之較短電流路徑1 7，則分別用於產 生該天線之第一（低頻）及第二（高頻）操作模態，且該較長 電流路徑1 6之長度接近該第一（低頻）操作模態共振頻率的 1 / 4波長，而該較短電流路徑1 7之長度則接近該第二（高 頻）操作模態共振頻率的1 / 4波長。另外如第2圖所示，該200414603 V. Description of the invention (3) Antenna made. [Embodiment] Referring to FIG. 3, an embodiment 1 of the inverted F-shaped antenna of the present invention includes: a radiating metal arm 10, which is rolled into a columnar shape by a radiating metal sheet 11 having at least one slit 1 1 3 A ground plane 13 includes a short-circuit point 1 31 and a ground point 1 32. The ground plane 13 may be a single metal sheet or formed on a microwave dielectric substrate by printing technology; a short-circuit metal The line 12 is an inverted L-shape with a feeding point 1 2 1 and the short-circuited metal line 12-one end is connected to the radiating metal arm 10 and the other end is connected to the short-circuit point 1 of the ground plane 13 3 1; and a coaxial line 14 for transmitting signals, the coaxial line 14 has a center wire 1 4 1 and an outer ground conductor 1 4 2, the center wire 1 4 1 is connected to the short-circuited metal wire The feeding point of 12 is 1 2 1, and the outer ground conductor 1 4 2 is connected to the ground point 1 3 1 of the ground plane 1 3. In this design, as shown in FIG. 3, the slit 1 1 3 extends from one edge of the radiating metal sheet 11 to the inside of the radiating metal sheet 1 1 so that the radiating metal sheet 11 is roughly divided into A longer son radiating metal sheet 1 1 1 and a shorter son radiating metal sheet 11 2, and a longer current path 16 on the longer son radiating metal sheet 11 1 and the shorter son radiating metal sheet 1 1 2 The shorter current path 17 is used to generate the first (low frequency) and second (high frequency) operating modes of the antenna, and the length of the longer current path 16 is close to the first (low frequency). The operating mode resonance frequency is 1/4 wavelength, and the length of the shorter current path 17 is close to the quarter frequency of the second (high frequency) operating mode resonance frequency. In addition, as shown in Figure 2, this
200414603 五、發明說明（4) 輻射金屬片11首先以印刷（printing)或蝕刻（etching)技 術形成在一軟性印刷電路板（flexible printed ck⑼it board)上，再捲成一柱狀結構並固定在保麗龍（f〇am)或塑 膠15上而形成该輕射金屬臂。 第4圖疋本發明天線一實施例丨的返回損失實驗量測結 果’·在本實施例中，該輻射金屬臂1〇其長度約為35 mm， 天線向度離接地面1 3之上緣約為8 mm，該較長之電流路徑 1 6其長度約為8 0 mm ;該較短之電流路徑丨7其長度約為4 〇 _，而該接地面13為一單一金屬片，其寬度及長度分別為 70 ππη及lOOjnm，該尺寸約為一PDA手機（PDA_ph〇ne)接地 面之大小，该饋入點1 2 1與該短路點1 3 1之距離約為1 〇 mm。由所得實驗結果，第一（低頻）操作模態4丨中心頻率位 於約9 2 5 Μ Η z，第二（高頻）操作模態4 2中心頻率位於約 1800 MHz，在電壓駐波比（vsWR)小於2.5的定義下，其操 作模態足夠涵蓋GSM( 8 9 0 - 9 6 0 MHz)及 DCS( 1 7 1 0 - 1 8 80 MHz) 兩個頻段。 第5圖為本發明天線輻射金屬片之其他實施例結構 圖。在實施例（a)圖中該輻射金屬片具有一狹縫5丨由該輻 射金屬片之一邊緣延伸至該輻射金屬片之内部，使該輻射 金屬片形成該較長56及該較短57之電流路徑，分別用於產 生該天線i之第一（低頻）41及第二（高頻）4 2操作模態；在 (b)圖中4狹縫51具有一第一支路狹縫511及一第二支路狹 縫512 \該狹縫51及該第二支路狹縫512用於產生該較短之 電流路徑57，而該三狹縫51，511及512則用於產生該較長200414603 V. Description of the invention (4) The radiating metal sheet 11 is first formed on a flexible printed ck⑼it board by printing or etching technology, and then rolled into a columnar structure and fixed to Poly The light-emitting metal arm is formed on a dragon or plastic 15. Fig. 4: Experimental measurement results of return loss of an embodiment of the antenna of the present invention '· In this embodiment, the length of the radiating metal arm 10 is about 35 mm, and the antenna is at a distance from the upper edge of the ground plane 13 About 8 mm, the longer current path 16 has a length of about 80 mm; the shorter current path 丨 7 has a length of about 40 mm, and the ground plane 13 is a single metal sheet with a width And the lengths are 70 ππη and 100jnm, respectively. The size is about the size of the ground plane of a PDA phone (PDA_phone). The distance between the feeding point 1 2 1 and the short-circuit point 1 31 is about 10 mm. From the obtained experimental results, the first (low-frequency) operating mode 4 丨 the center frequency is located at about 9 2 5 Μ Η z, and the second (high-frequency) operating mode 4 2 is located at the center frequency of about 1800 MHz. Under the definition of vsWR) less than 2.5, its operating mode is sufficient to cover the two bands of GSM (890-9600 MHz) and DCS (1710-1 8 80 MHz). Fig. 5 is a structural diagram of another embodiment of the antenna radiation metal sheet of the present invention. In the embodiment (a), the radiation metal sheet has a slit 5 丨 extending from one edge of the radiation metal sheet to the inside of the radiation metal sheet, so that the radiation metal sheet forms the longer 56 and the shorter 57 The current paths are used to generate the first (low frequency) 41 and the second (high frequency) 4 2 operating modes of the antenna i; in (b), the 4 slit 51 has a first branch slit 511 And a second branch slit 512 \ the slit 51 and the second branch slit 512 are used to generate the shorter current path 57, and the three slits 51, 511 and 512 are used to generate the shorter current path 57 long
200414603 五、發明說明（5) 之電流路徑5 6 ;而在（c )圖中該輻射金屬片則具有兩狹縫 5 1及52，該狹縫5 1用於產生該較短之電流路徑57，而該兩 狹縫5 1及52則用於產生該較長之電流路徑56。 第6圖為本發明天線短路金屬線6 1之其他實施例結構 圖。在實施例（a)圖中，該短路金屬線6 1為一樓梯狀，具 有三個約為9 0度之折彎，在（b)圖中則為一由饋入點6 2往 右延伸之垂直婉蜒路徑，而在（c)圖中則為一由饋入點6 2 往下延伸的水平蜿蜒路徑。 以上說明中所述之實施例僅為說明本發明之原理及其 功效，而非限制本發明。因此，習於此技術之人士可在不 違背本發明之精神對上述實施例進行修改及變化。本發明 之權利範圍應如後述之申請專利範圍所列。200414603 V. The current path 5 6 of the description of the invention (5); and in the figure (c), the radiating metal sheet has two slits 51 and 52, and the slit 51 is used to generate the shorter current path 57 The two slits 51 and 52 are used to generate the longer current path 56. Fig. 6 is a structural diagram of another embodiment of the short-circuited metal wire 61 of the antenna of the present invention. In the embodiment (a), the short-circuiting metal wire 61 is a staircase shape with three bends of about 90 degrees, and in the (b) diagram, it extends from the feeding point 62 to the right. It is a vertical meandering path, and in (c) it is a horizontal meandering path extending downward from the feeding point 6 2. The embodiments described in the above description are only for explaining the principle of the present invention and its effects, but not for limiting the present invention. Therefore, those skilled in the art can modify and change the above embodiments without departing from the spirit of the present invention. The scope of rights of the present invention should be listed in the scope of patent application mentioned later.
第11頁 200414603 圖式簡單說明 第圖第第 構 結 之 緣 上 面 地 接一 於 置 例 施 實一 線 天 明 發 本 為 圖 之 面 平 為 gm 展 臂 屬 金 射 輻 J5I 之 例 施 實 结卩一 面 彳線 J天 之明 圖 1發 第本 為為 圖圖 圖 構 結第 圖 果 結 測 量 驗 實 失 損 回 返 之 例 施 實一 線 天 明 發 本 為 圖 圖圖 構構 結結 例例 施施 實實 他他 其其 片線 屬屬 金金 射路 輻短 之之 線線 天天 明明 發發 本本 為為 圖圖 5 6 第第 明 說 # 符 件 元 例 施 實 1 線 天 形 F 倒 之 明 發 本Page 11 200414603 The diagram briefly explains the edge of the first structure in the figure. The ground is connected to the example to implement the first line. The face of the hair is shown in the figure. The flat is gm. The arm is of the golden spoke J5I. Squall line J Tianzhiming Figure 1 This is the example of the structure of the figure and the figure The result of the measurement and the return of the actual loss is implemented. The first line of Tianming is the example of the structure and the figure of the figure His other line is a short line of gold and gold shots. The Tiantian Mingfa's book is shown in Figure 5 6. 第 第 明说 # 件 件 元 例 施 1 Line Tian F's inverted Mingfa
11 IX11 IX
11 oo 1X 1X 1X 2 2 3 3 3 4 11 11 11 11 11 11 占 占占 金金金"!面!!.1同 長短縫入路地 較較狹α饋；2短接h 輻輻 短接 饋 臂片 子子 之之 圖 構 結 之 面 平 為 af、 am 展 臂 屬片片 金屬屬 射金金 輻射射 J3I Juw— 線 屬 線 轴11 oo 1X 1X 1X 2 2 3 3 3 4 11 11 11 11 11 11 Zhanzhanzhanjinjinjin "! 面 !!. 1 narrower α feed with the same length and short slot; 2 short-circuited h-spoke short-circuited The structure of the feeding arm film is flat, the surface is af, am, the arm is a piece of metal, the metal is gold, the gold is radiating, and the J3I Juw is a wire.
第12頁 200414603 圖式簡單說明 1 4 1 :中心導線 1 4 2 :外層接地導體 15 保 麗龍（f 〇 a m ) 或 塑 膠 16 較 長之電流 路 徑 17 較 短之電流 路 徑 41 : 第 一（低頻） 操 作 模 態 42 : 第 二（南頻） 操 作 模 態 51 :狹縫 5 1 1 :第一支路狹縫 5 1 2 :第二支路狹縫 5 2 :狹縫 5 6 :較長之電流路徑 5 7 :較短之電流路徑 61 :短路金屬線 6 2 :饋入點Page 12 200414603 Brief description of the drawings 1 4 1: Central wire 1 4 2: Outer ground conductor 15 Polylon (f 0am) or plastic 16 Longer current path 17 Shorter current path 41: First (low frequency ) Operation mode 42: Second (South frequency) Operation mode 51: Slot 5 1 1: First branch slit 5 1 2: Second branch slit 5 2: Slot 5 6: Longer Current path 5 7: Shorter current path 61: Short-circuited metal wire 6 2: Feed point
第13頁Page 13
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| TW92101916A TW575979B (en) | 2003-01-24 | 2003-01-24 | An inverted-F antenna |
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| TW92101916A TW575979B (en) | 2003-01-24 | 2003-01-24 | An inverted-F antenna |
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| TW575979B TW575979B (en) | 2004-02-11 |
| TW200414603A true TW200414603A (en) | 2004-08-01 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI757091B (en) * | 2021-02-09 | 2022-03-01 | 緯創資通股份有限公司 | Antenna structure |
Families Citing this family (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI347037B (en) | 2007-11-15 | 2011-08-11 | Htc Corp | Antenna for thin communication apparatus |
| TWI409993B (en) * | 2009-11-27 | 2013-09-21 | Quanta Comp Inc | Multi - frequency antenna |
| TWI469445B (en) * | 2011-03-01 | 2015-01-11 | Inpaq Technology Co Ltd | Multi-band antenna |
| TWI542073B (en) | 2011-08-04 | 2016-07-11 | 智易科技股份有限公司 | Multi-band inverted-f antenna |
| EP3462542B1 (en) * | 2017-10-02 | 2021-05-19 | Nokia Shanghai Bell Co. Ltd. | Antenna and method of assembly of such antenna |
| CN111864370B (en) * | 2020-08-07 | 2023-08-04 | 常州柯特瓦电子有限公司 | Antenna structure |
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2003
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| TWI757091B (en) * | 2021-02-09 | 2022-03-01 | 緯創資通股份有限公司 | Antenna structure |
| CN114914671A (en) * | 2021-02-09 | 2022-08-16 | 纬创资通股份有限公司 | Antenna structure |
| US11670853B2 (en) | 2021-02-09 | 2023-06-06 | Wistron Corp. | Antenna structure |
Also Published As
| Publication number | Publication date |
|---|---|
| TW575979B (en) | 2004-02-11 |
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