200950209 九、發明說明： 【發明所屬之技術領域】 • 本發明係關於一種行動通訊裝置天線，特別是一種具 . 有電容元件之多頻行動通訊裝置天線。 【先前技術】 隨著無線通訊產業的蓬勃發展，現今幾乎已成為人手 Ο —機的普及情況，而行動電話的設計除了仍力求輕、薄、 短、小外，在通訊頻帶上的需求，已從原本的雙頻操作變 成多頻操作，使得行動電話所能提供的無線通訊服務更多 元化。而多頻天線的設計大致分為多天線的設計及單一寬 頻天線兩種，前者必然造成天線擺放空間的規劃、高天線 製作成本以及電磁干擾等問題；後者則是使得内部空間能 得到有效的運用，成本也可以降低。因此設計具有多頻帶 操作特性之單一天線為一較佳之解決方案，不過，天線寬 ❹頻機制與技術之開發將會是另一個挑戰，故天線設計需要 尋求寬頻的解決方案來符合多頻帶操作的需求。 台灣專利公告號第1245,450號“平面倒F形天線”及 台灣專利公告號第1286,857號“印刷式天線”，皆為適用 於行動通訊裝置之天線，然而其皆只能產生單一模態單共 振，無法涵蓋足夠寬的頻寬。若將上述之先前技術應用於 手機通訊頻帶，將不易涵蓋低頻GSM850/900 (824 - 894 MHz/ 5 .200950209 890-960MHZ)雙頻操作的需求，而低頻(900MHz)頻帶之操 作頻寬不足’往往是天線縮小化設計的瓶頸。 為了解決上述的問題，我們提出一種具有電容元件之 • 多頻行動通訊裝置天線，藉由一串接電容元件所提供的電 容量，來補償傳統手機天線在低頻(900MHz)頻帶之輸入阻 抗的高電感性。在選擇適當的電容元件值之後，能在低頻 (900MHz)頻帶有效產生單一模態雙共振，藉由此雙共振所 ❹涵蓋的較寬頻寬，達成涵蓋GSM850/900之操作需求。同時 ’在串接該電容元件之後，也能改善高頻（1800 MHz)頻帶 之阻抗匹配’達成涵蓋 GSM180(V1900(1710- 1880MHz/1850 • 1990MHz)之操作頻帶。使用上述方法之後，能使天線整 體達成GSM850/900/1800/1900之四頻操作需求。 【發明内容】 ❹ 如上所述，本發明之目的在於提供一種適用於行動通 訊裝置之多頻天線設計，其可以涵蓋GSM85〇/9〇(V18〇〇/19〇〇 頻帶之操作。 本發明天線，包含：一介質基板，該介質基板可為一 行動通訊裝置之系統電路板；一接地面，該接地面可以使 用印刷或蝕刻技術形成於該介質基板之一表面上，具有一 短路點，且該短路點位於該接地面之一邊緣；一輻射金屬 部，為一支撐介質所支撐，該支撐介質材質可為空氣、玻 6 .200950209 纖基板、塑膠材料或陶究材料，為一立體結構，並位於該 質基板之表面上，該輻射金屬部可以使用印刷、餘刻 -或濺鑛技術形成於該支樓介質上，亦可以使用一金屬片沖 ，壓或切割製作而成，再依附於該支樓介質上，且與該接地 面不互相重疊，並電氣連接至該接地面之短路點，該韓射 金屬部並包含：-第-輻射部，其一端位於該接地面之一 邊緣附近，為天線之饋入點，另一端為開路；一第二輕射 ❹部，其一鈿電氣連接至該第一輻射部，另一端為開路；及 一短路金屬部，其一端電氣連接至該第二輻射部，另一端 電氣連接至該接地面之短路點；以及一電容元件，該電容 元件可為一晶片電容，位於該介質基板之一表面上，其一 端電氣連接至該饋入點，另一端電氣連接至一信號源。 在本項發明天線中’藉由第一金屬部共振出其四分之 一波長模態（操作於約1800MHz)，以及第二金屬部共振 ^ 出其四分之一波長模態（操作於約900 MHz)。然而天線在 未串接一電容元件時，低頻(900MHz)頻帶之輸入阻抗電感 性太強，造成天線與信號源阻抗不匹配，無法有效將信號 源之能量馈入天線’因此我們提出使用一串接電容元件的 方式來解決上述問題。在選擇適當的電容元件值之後’藉 由該串接電容元件所提供的電容量，有效補償天線在低頻 (9〇〇MHz)頻帶之輸入阻抗高電感性，使得在低頻(900MHz) 頻帶，產生雙降扳虚部零點’並搭配適當的實部阻抗’進 7 200950209 而產生單一模態雙共振，達成涵蓋GSM850/900之操作頻帶 需求’解決傳統手機天線在低頻(900MHz)頻帶不容易涵蓋 .雙頻操作的問題；同時也藉由該串接電容元件，對於高頻 (1800MHz)之輸入阻抗高電感性做補償，改善高頻頻帶之 匹配，進而涵蓋GSM1800/1900頻帶操作。因此使用—串接 電容元件補償天線輸入阻抗高電感性的方法，能有效解決 傳統手機天線致力於縮小化的同時，低頻(9〇〇MHz)頻帶不 ❹容易涵蓋GSM850/900雙頻操作的問題，進而達成Gsm85〇/ 900/1800/1900之多頻操作需求。 實施方式】 第1圖為本發明天線一實施例結構圖丨，包含：一介 ϋ板^ —接地面12，位於該介質基板U之-表面上 Ο 邊^短路點121，且該短路點121位於該接地面12之一 ίίί播—輻射金屬部14 ’為—域介質⑽支律，為〜 立體結構，並位於該介皙其 馬 12不互相重疊，且電氣== 面二::該接地面 該轉射金屬部14並包含面12之短路點121， 該接地斷一邊二Γ 部141 ’其—端仅於 為開路一第二=4;天線之饋入點145，另-端 射部⑷，另—料㈣其—端電氣連接至該第1 電知切 &為開路；及—短路金>1部143，JL —她 電礼連接至鮮二_部丨42，另_端電氣連接至該接= 8 200950209 面12之短路點121 ;以及一電容元件15,位於該介質基板 11之一表面上，其一端電氣連接至該饋入點145，另一端 . 電氣連接至一信號源16。 第2圖為本發明天線一實施例之串接電容元件等效電 路圖。藉由該串接電容元件的電容量，可以有效補償天線 之高電感性’在低頻(900 MHz)頻帶形成單一模態雙共振以 及高頻（1800 MHz)頻帶之寬頻模態，進而達成多頻操作。 ❹ 參 第3圖為本發明天線一實施例丨之返回損失圖。在實 施例1中選擇下列尺寸來進㈣驗：介f基板u長度約為 l〇5mm、寬度約為60mm ;接地面叫度約為1〇〇麵、寬 度約為60麵；支樓介fl3長度約為⑼議、寬度約為5 腿、高度約為，其材質在此為空氣，亦可使用玻 板、_㈣或陶W料為切介質；輻射金屬部Μ ，包含：第一輻射部141為—τ够& ^ ^ ^ 馬不等寬設計，在末端加寬寬 度’寬度約為5 mm ;第-^ 乐一輻射部142為一不等寬設計， 在末端加寬寬度，寬度約At a 又J馮5mm ;短路金屬部143長度 約為5mm 、寬度約為i . q imm ，電容兀件15 電容，其電容值約為l.5pF。电200950209 IX. Description of the Invention: [Technical Field of the Invention] The present invention relates to a mobile communication device antenna, and more particularly to a multi-frequency mobile communication device antenna having a capacitive element. [Prior Art] With the rapid development of the wireless communication industry, it has become a popularization of human-machines, and the design of mobile phones is still demanding light, thin, short, and small, in the communication band. From the original dual-band operation to multi-frequency operation, the wireless communication service provided by the mobile phone is more diversified. The design of multi-frequency antenna is roughly divided into multi-antenna design and single broadband antenna. The former will inevitably cause the problem of antenna placement space, high antenna fabrication cost and electromagnetic interference; the latter is to make the internal space effective. The cost can also be reduced. Therefore, designing a single antenna with multi-band operation characteristics is a better solution. However, the development of antenna wide frequency mechanism and technology will be another challenge, so the antenna design needs to find a broadband solution to comply with multi-band operation. demand. Taiwan Patent Publication No. 1245, 450 "Planar Inverted F Antenna" and Taiwan Patent Publication No. 1286,857 "Printed Antenna" are antennas suitable for mobile communication devices, but they can only produce a single mode. State single resonance, can not cover a wide enough bandwidth. If the above prior art is applied to the mobile phone communication band, it will not be easy to cover the requirements of the low frequency GSM850/900 (824 - 894 MHz / 5 .200950209 890-960MHZ) dual frequency operation, and the operating bandwidth of the low frequency (900 MHz) band is insufficient. It is often the bottleneck of the antenna downsizing design. In order to solve the above problems, we propose a multi-frequency mobile communication device antenna with capacitive components, which compensates for the high input impedance of the conventional mobile phone antenna in the low frequency (900 MHz) band by the capacitance provided by a series of capacitive elements. Inductive. After selecting the appropriate capacitive component value, a single mode double resonance can be effectively generated in the low frequency (900 MHz) band, and the wide bandwidth covered by the double resonance can achieve the operational requirements covering the GSM850/900. At the same time, 'the impedance matching of the high frequency (1800 MHz) band can be improved after the capacitor element is connected in series'. The operating band covering GSM180 (V1900 (1710-1880MHz/1850 • 1990MHz) is achieved. After using the above method, the antenna can be made. Overall, the GSM850/900/1800/1900 quad-band operation requirements are met. SUMMARY OF THE INVENTION As described above, an object of the present invention is to provide a multi-frequency antenna design suitable for a mobile communication device, which can cover GSM85〇/9〇( The operation of the V18〇〇/19〇〇 band. The antenna of the present invention comprises: a dielectric substrate, which can be a system circuit board of a mobile communication device; a ground plane, which can be formed by printing or etching techniques. One surface of the dielectric substrate has a short-circuit point, and the short-circuit point is located at one edge of the ground plane; a radiating metal portion is supported by a supporting medium, and the supporting medium material can be air, glass 6.200950209 fiber The substrate, the plastic material or the ceramic material is a three-dimensional structure and is located on the surface of the substrate, and the radiant metal portion can be printed, engraved - or The splashing technology is formed on the medium of the branch building, and can also be made by punching, pressing or cutting a metal piece, and then attached to the medium of the branch building, and does not overlap with the grounding surface, and is electrically connected to the connection. a short-circuit point on the ground, the Korean metal portion includes: a first-radiation portion, one end of which is located near one edge of the ground plane, is a feeding point of the antenna, and the other end is an open circuit; a second light-emitting portion, One end is electrically connected to the first radiating portion, and the other end is an open circuit; and a short-circuited metal portion, one end of which is electrically connected to the second radiating portion, the other end is electrically connected to a short-circuit point of the grounding surface; and a capacitive element The capacitive element can be a chip capacitor on a surface of the dielectric substrate, one end of which is electrically connected to the feed point, and the other end is electrically connected to a signal source. In the antenna of the present invention, 'by the first metal The part resonates with its quarter-wave mode (operating at about 1800 MHz), and the second metal part resonates with its quarter-wave mode (operating at about 900 MHz). However, the antenna is not connected in series with a capacitor. When the component is The input impedance of the frequency band (900MHz) is too inductive, causing the antenna and signal source impedance to be mismatched, and the energy of the signal source cannot be effectively fed into the antenna. Therefore, we propose to use a series of capacitive components to solve the above problem. After selecting the appropriate capacitive component value, 'the capacitance provided by the series capacitive component effectively compensates for the high inductivity of the input impedance of the antenna in the low frequency (9 〇〇 MHz) band, resulting in a double in the low frequency (900 MHz) band. Drop the imaginary zero point 'and match the appropriate real impedance' into 7 200950209 to produce a single mode double resonance, reaching the operating band requirements covering GSM850/900 'solving the traditional mobile phone antenna in the low frequency (900MHz) band is not easy to cover. Double The problem of frequency operation; at the same time, the high-frequency (1800MHz) input impedance is highly inductively compensated by the series capacitor element, and the matching of the high-frequency band is improved, thereby covering the GSM1800/1900 band operation. Therefore, the method of using the series-connected capacitor element to compensate the high inductivity of the antenna input impedance can effectively solve the problem that the conventional mobile phone antenna is being reduced, and the low-frequency (9 〇〇 MHz) band is not easy to cover the GSM850/900 dual-frequency operation. In order to achieve the multi-frequency operation requirements of Gsm85〇/900/1800/1900. Embodiment 1 is a structural diagram of an embodiment of an antenna according to the present invention, comprising: a dielectric layer 12, a ground plane 12 on a surface of the dielectric substrate U, a short-circuit point 121, and the short-circuit point 121 is located One of the ground planes 12 is a ray-radiation metal portion 14' is a domain medium (10), which is a three-dimensional structure, and the horses 12 are not overlapped with each other, and the electric== face two:: the ground plane The transfer metal portion 14 includes a short-circuit point 121 of the surface 12, and the ground-breaking side of the second portion 141' is only open for a second = 4; the feed point 145 of the antenna and the other end portion (4) , the other material (four) its - terminal electrical connection to the first electric cut & open circuit; and - short circuit gold > 1 143, JL - her gift is connected to the fresh two _ 丨 丨 42, another _ _ electric Connected to the short circuit point 121 of the surface 12; and a capacitor element 15 on one surface of the dielectric substrate 11, one end of which is electrically connected to the feed point 145, and the other end. Electrically connected to a signal source 16. Fig. 2 is an equivalent circuit diagram of a series capacitor element according to an embodiment of the antenna of the present invention. By the capacitance of the series capacitor element, the high inductance of the antenna can be effectively compensated to form a single mode double resonance and a high frequency (1800 MHz) band wide frequency mode in the low frequency (900 MHz) band, thereby achieving multi-frequency. operating.第 第 Figure 3 is a diagram showing the return loss of an embodiment of the antenna of the present invention. In the first embodiment, the following dimensions are selected to enter (4): the length of the substrate u is about l〇5 mm and the width is about 60 mm; the grounding surface is about 1 〇〇, and the width is about 60; The length is about (9), the width is about 5 legs, the height is about, the material is air here, and the glass plate, _(four) or ceramic material can be used as the cutting medium; the radiation metal part Μ includes: the first radiation part 141 For the τ sufficiency & ^ ^ ^ horse unequal width design, the width is widened at the end 'width is about 5 mm; the first - ray-radiation part 142 is a unequal width design, widening the width at the end, the width is about At a and J von 5mm; the short-circuited metal portion 143 has a length of about 5 mm and a width of about i. q imm , and the capacitance of the capacitor element 15 has a capacitance value of about 1.5 pF. Electricity
Ρ 由所得之實驗結果，在6dB 返回損失的定義之下，該笛_ A gg 奸广 —金屬部之共振模態31足以涵Ρ From the experimental results obtained, under the definition of 6dB return loss, the flute _ A gg 广 — - the resonance mode of the metal part 31 is sufficient
蓋GSM1800/1900頻帶，而钤货 A μ第一金屬部之共振模離32，足 以涵蓋GSM850/900頻帶，因 足 此天線旎多頻操作於GSM850/ 900/1800/1900 頻帶。 9 200950209The GSM1800/1900 band is covered, and the resonant mode of the first metal part of the A μ is separated by 32, which covers the GSM850/900 band, because the antenna is multi-frequency operated in the GSM850/900/1800/1900 band. 9 200950209
第4®* 一——， :一介質 一接地面· 點 421， 輻射金屬 -表面上’亦可由—金屬片沖壓或㈣製作而成 该介質基板41之-表面上，與該接地面42不互相重疊且 ®該輻射金屬部44電氣連接至該接地面42之短路點42^，並 包含：一第一輻射部441，其一端位於該接地面“之丄邊 緣附近，為天線之饋入點445，另一端為開路；一第二輕 射部442，其一端電氣連接至該第一輻射部44ι，另一端 ^開路；及-短路金屬部443，其一端電氣連接至該第二 輻射部442，另一端電氣連接至該接地面42之短路點421 :以及一電容元件45，該電容元件可以為一晶片電容，位 ❹於該介質基板41之-表面上，其一端電氣連接至該饋入點 445，另一端電氣連接至一信號源牝。實施例4與實施例 1的差異在於實施例1之輻射金屬部14是以支撐介質13支 撐，為一立體結構，而實施例4之輻射金屬部44則是一平 面結構。該兩個實施例，其操作原理相同，實施例4亦可 得到與實施例1之相似結果’皆可涵蓋GSM85〇/9〇〇/丨 1900之多頻操作’可依實際需求選擇較適當的天線結構。 以上說明中所述之實施例僅為說明本發明之原理及其 200950209 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。 ' 【圖式簡單說明】 第1圖為本發明天線一實施例結構圖。 第2圖為本發明天線一實施例之串接電容元件等效電路圖 〇 © 第3圖為本發明天線一實施例之量測返回損失圖。 第4圖為本發明天線之一其他實施例結構圖。 【主要元件符號說明】 1 :本發明天線一實施例 11,41 :介質基板 12,42 :接地面 121,421 :短路點 13 :支撐介質 14,44 :輻射金屬部 141,441 :第一輻射部 142,442 :第二輻射部 143,443 :短路金屬部 144,444 :第一輻射部與第二輻射部連接點 145,445 :饋入點 15,45 :電容元件 11 200950209 16,46 31 32 4 :信號源 :南頻共振頻帶 :低頻共振頻帶 本發明天線之一其他實施例4®*1—, : a medium-grounding surface·point 421, a radiant metal-surface' may also be formed by sheet metal stamping or (iv) on the surface of the dielectric substrate 41, and the ground plane 42 is not The radiant metal portion 44 is electrically connected to the short-circuit point 42 of the ground plane 42 and includes: a first radiating portion 441, one end of which is located near the edge of the ground plane, and is a feeding point of the antenna 445, the other end is an open circuit; a second light-emitting portion 442, one end of which is electrically connected to the first radiating portion 44ι, the other end is open; and - a short-circuited metal portion 443, one end of which is electrically connected to the second radiating portion 442 The other end is electrically connected to the short-circuit point 421 of the ground plane 42 and a capacitor element 45, which may be a wafer capacitor located on the surface of the dielectric substrate 41, one end of which is electrically connected to the feed Point 445, the other end is electrically connected to a signal source. The difference between Embodiment 4 and Embodiment 1 is that the radiating metal portion 14 of Embodiment 1 is supported by the supporting medium 13, which is a three-dimensional structure, and the radiating metal of Embodiment 4 Part 44 is a planar structure The two embodiments have the same operation principle, and the fourth embodiment can also obtain similar results to the first embodiment, which can cover the multi-frequency operation of GSM85〇/9〇〇/丨1900, which can be selected according to actual needs. The embodiment described in the above description is only for explaining the principle of the present invention and its 200950209 function, and is not intended to limit the present invention. Therefore, those skilled in the art can carry out the above embodiments without departing from the spirit of the present invention. Modifications and variations. The scope of the present invention should be as set forth in the appended claims. ' [Simple Description of the Drawings] FIG. 1 is a structural view of an embodiment of an antenna according to the present invention. FIG. 2 is an embodiment of an antenna according to the present invention. The equivalent circuit diagram of the series capacitor element is shown in Fig. 3. Fig. 3 is a diagram showing the measurement return loss of an antenna according to an embodiment of the present invention. Fig. 4 is a structural diagram of another embodiment of the antenna of the present invention. The antenna of the present invention is an embodiment 11, 41: dielectric substrate 12, 42: ground plane 121, 421: short-circuit point 13: supporting medium 14, 44: radiating metal portion 141, 441: first radiating portion 142, 442: second radiating portion 143, 443: short-circuit metal portion 144, 444: first radiation portion and second radiation portion connection point 145, 445: feed point 15, 45: capacitive element 11 200950209 16, 46 31 32 4 : signal source: south frequency resonance frequency band: low frequency resonance frequency band One embodiment of the inventive antenna