Ί376839 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種多頻帶天線(multiband antenna)， 且特別是有關於一種於侷限體積内能多頻通訊且保持良好 通訊品質的多頻帶天線。 【先前技藝】 • 請參閱圖一至圖三，傳統的天線有單極天線 (Monopole antenna)l、迴路天線(Loop antenna)2 及平面倒 F 型天線(Planar Inverted-F Antenna, PIFA)3。單極天線 1 所激發之電磁波之共振模態頻率由訊號饋入端10至開路 端12之間的路徑長決定；迴路天線2所激發之電磁波之 共振模態頻率由訊號饋入端20至接地端22之間的路徑長 所決定；平面倒F型天線3類似於迴路天線2及單極天線 1的組合，可激發出兩種不同共振模態頻率的電磁波，其 φ 中之一共振模態頻率由訊號饋入端30至接地端32之間的 路徑長所決定，另一共振模態頻率由訊號饋入端3〇至開 路端34之間的路徑長所決定。 近年來’隨著行動通訊產業的發展，早期天線設計為 外露螺旋天線(Helical antenna)，後期天線設計為了因應電 子產品的輕薄趨勢而發展出整合於產品内部的隱藏式天 線，例如迴路天線、單極天線或平面倒F型天線。目前而 言，隱藏式天線已經成為行動通訊裝置的設計主流。然 而，以手機為例，手機並非只有接聽及播打電話的二能、，'、 [S3 4 Ϊ有樂、無線上網、GPS定位甚至行動電視功 為了正^種功能’手機的内部電路模組也愈多且越 4夭=:的容納空間越來越小。隨著天線體積縮 /、發射及接收訊號的效率（通訊品質）也會而變 择天縣構本身的尺寸仍存在其_赌， :=收訊的品質依舊不變，是目前行動通訊領域很 戈' 的議題之一。 2 ’本發明提供-種多頻帶天線，能夠於侷限的容 吶工間内，於不同頻段下仍保持良好的通訊品質。 【發明内容】 本發明之一 限的容納空間内 通訊品質。 範疇在於提供一種多頻帶天線，能夠於侷 ，支援多頻帶的訊號傳遞且能保持良好的 為了達成上述範疇，於一實施例中，本發明之多頻帶Ί 376839 VI. Description of the Invention: [Technical Field] The present invention relates to a multi-band antenna, and more particularly to a multi-band antenna capable of multi-frequency communication in a limited volume and maintaining good communication quality. [Previous Skills] • Referring to Figures 1 to 3, the conventional antenna has a monopole antenna, a loop antenna 2, and a Planar Inverted-F Antenna (PIFA) 3. The resonant mode frequency of the electromagnetic wave excited by the monopole antenna 1 is determined by the path length between the signal feeding end 10 and the open end 12; the resonant mode frequency of the electromagnetic wave excited by the loop antenna 2 is fed from the signal feeding terminal 20 to the ground. The path length between the ends 22 is determined; the planar inverted F antenna 3 is similar to the combination of the loop antenna 2 and the monopole antenna 1 and can excite two electromagnetic waves of different resonant mode frequencies, one of which has a resonant mode frequency The path length between the signal feed terminal 30 and the ground terminal 32 is determined, and the other resonant mode frequency is determined by the path length between the signal feed terminal 3 〇 and the open terminal 34. In recent years, with the development of the mobile communication industry, the early antennas were designed as Helical antennas. The late antenna design developed a hidden antenna integrated in the product in response to the thin and light trend of electronic products, such as loop antennas and singles. Pole antenna or planar inverted F antenna. At present, hidden antennas have become the mainstream of mobile communication devices. However, taking mobile phones as an example, mobile phones are not the only ones that can answer and broadcast calls. ', [S3 4 Ϊ有乐, wireless Internet access, GPS positioning, and even mobile TV functions for the correct function of the mobile phone's internal circuit module The more and the 4 夭 =: the accommodation space is getting smaller and smaller. As the size of the antenna shrinks, the efficiency of the transmission and reception of signals (communication quality) will also change the size of the Tianxian structure itself, there is still its _ gambling, := The quality of the reception remains unchanged, which is very good in the field of mobile communication. One of the topics of Ge's. 2 </ RTI> The present invention provides a multi-band antenna capable of maintaining good communication quality in different frequency bands in a limited capacity workspace. SUMMARY OF THE INVENTION The communication quality in the accommodation space is limited by one aspect of the present invention. The invention provides a multi-band antenna capable of supporting multi-band signal transmission and maintaining good performance in order to achieve the above-mentioned scope. In one embodiment, the multi-band of the present invention
天線包含迴路微帶線及寄生微帶線。迴路微帶線包含訊Z ^入端及第—接地端’從訊號饋人端至第-接地端的路^ 長為二分之一波長。寄生微帶線包含第二接地端及第一ς 路端’從第一開路端至第二接地端的路徑長為四分之一& 長。 訊號由迴路微帶線之訊號饋入端輪入，使得迴路微帶 線激發出第一共振模態頻率。寄生微帶線被迴路 包^第-共振模態頻率的電磁輻射輕合至寄生微=所 使得寄生微帶線激發出第二共振模態頻率，其中第二乓费 1376839 模態頻率異於第一共振模態頻率。 於另一實施例中，本發明之多頻帶天線另包含連接至 迴路微帶線之開路微帶線。開路微帶線包含第二開路端， 從訊號饋入端至第二開路端的路徑長為四分之—波長。訊 號由訊號饋入端輸入後，使得開路微帶線激發出第三妓振 模態頻率’其令第三共振模態頻率異於第二共振模態頻率 及第一共振模態頻率。 ~The antenna includes a loop microstrip line and a parasitic microstrip line. The loop microstrip line includes the signal from the signal feed end to the ground end of the signal Z^ input terminal and the ground terminal end at a wavelength of one-half wavelength. The parasitic microstrip line includes a second ground end and a path of the first turn end 'from the first open end to the second ground end is one quarter & The signal is clocked in by the signal feed end of the loop microstrip line, causing the loop microstrip line to excite the first resonant mode frequency. The parasitic microstrip line is lightly coupled by the electromagnetic radiation of the first-resonant mode frequency to the parasitic micro-=the parasitic microstrip line excites the second resonant mode frequency, wherein the second puncture is 1376839. The modal frequency is different from the first A resonant modal frequency. In another embodiment, the multi-band antenna of the present invention further includes an open microstrip line connected to the loop microstrip line. The open microstrip line includes a second open end, and the path from the signal feed end to the second open end is four quarters long. After the signal is input from the signal feeding end, the open microstrip line excites the third resonant mode frequency, which causes the third resonant mode frequency to be different from the second resonant mode frequency and the first resonant mode frequency. ~
本發明之多頻帶天線透過迴路微帶線圍繞寄生微帶線 的線路設計’且透過寄生微帶線一端接地且另—端開路的 方式，激發出兩種不同的共振模態頻率。迴路微帶線所激 發之具有第一共振模態頻率的電磁輻射可耦合至寄生微帶 ，，致使寄生微帶線激發出第二共振模態頻率。本發明之 多頻帶天線不但增加了支援(接收及發射職)的頻^，且 ^需額外佔據體積(寄生微帶線被迴路微帶線所包圍）。再 發明之迴路微帶線及寄生微帶線的路徑長度可適當 且㈣限的容納好:=j通訊功能’ 所附神可以藉由《下的發明詳述及 【實施方式】 機通訊領域，以 本發明之多鮮天線主要可應用於手 6 1376839 滿足手機的多頻通訊功能。舉例來說，手機的通訊頻段有 全球通訊系統 900(Global System for Mobile Communications 900, GSM 900)所規範之 880〜960MHz、 分散控制系統(Distributed Control System, DCS)所規範的 1710〜1880MHz、個人通訊服務（Personal Communiations Service, PCS)所規範之1850〜1990MHz及寬頻分碼多工 (Wide band Code Division Multiple Access，WCDMA)所規 範之 1920〜2170MHz。 本發明之多頻帶天線主要透過特殊的微帶線配置及電 磁輻射耦合作用，於侷限的體積内能激發出不同頻率的電 磁波’並且保持良好通訊品質。本發明之多頻帶天線係如 何達成上述結果’請參閱下述實施例說明。 晴參閱圖四A及圖四B。圖四A繪示根據本發明一 具體實施例之多頻帶天線4之示意圖。圖四B %示圖四 A之多頻帶天線4之另一視角。如圖四A及圖四b所 示，本發明之多頻帶天線4包含迴路微帶線40及寄生微 帶線42，迴路微帶線40及寄生微帶線42皆貼附於電性 絕緣的支撐體49上。 迴路微帶線40包含延伸及貼附於支撐體49的第二平 面490的訊號饋入端400及第一接地端402。迴路微帶線 40從訊號饋入端400開始依序地沿著第二平面49〇、第三 平面492及第一平面494延伸，再依序沿著第—平面 494、第三平面492及第二平面490延伸至第一接地端 402，第一接地端402連接於金屬接地件48而接地。 r 1376839 -寄生微帶線42包含延伸及貼附於第二平面_的第 -接地端422，以及包含延伸且貼附於第_平面例的第 端Γ。寄主微帶線從第二接地端422開始依序地 mi _及第三平面492延伸至第-開路端 第一接地端422連接於金屬接地件48而接地。 從訊號饋入端400至第-接地端4〇2的路徑長為二分 ί開路端42°至第二接地端422的路徑長 二號由迴路微帶線40之訊號饋入端 二微帶線4g所㈣，並且寄生微 帶線40之間有一間隙(_，而間隙的 不㈣，寄生微帶線42與迴路微帶線4 觸即可。迴路微帶線40所激發出的具有第 =的電磁輻射可搞合至寄生微帶線&，使得寄'“帶線 為了不^^輸人就可激發出第二共振模態辭。其中、， 頻段，第二共振模態頻率異於該第一共 可透i電磁輕射二:=帶:匕2不需要訊號輸入’就 I :生 另一頻段的共振模態頻率。= 積上因Γ 本迴路微帶線仙所包圍的面 體體積)據額外線路面積(不增加天線所佔據的整 明之接Γ發射其他通訊頻率的訊號，本於 一如圖四Α及圖四Β所示。開路微帶線44包^ 8 第=開路端440，從訊號饋入端400至第二開路端440的 路徑長為四分之一波長。訊號由訊號饋入端400輸入後’ 除了流經迴路微帶線40之外，也可流經開路微帶線44， 因此使得開路微帶線44激發出第三共振模態頻率。其 中’為了涵蓋不同通訊頻段，第三共振模態頻率異於第二 共振模態頻率及第一共振模態頻率。 若本發明之多頻帶天線置入於手機内，支撐體49的 第二表面490及第一表面494分別對應手機的正面及背 面’因此厚度d(相當於手機的正面到背面之間的距離）的 大小影響到手機的整體厚度。但是，厚度d太小，天線的 線路之間（例如：天線與金屬接地件48間）容易產生干 擾’厚度d太大則讓手機不易縮小整體體積。如圖四a 及圖四B所示，寄生微帶線42設置於迴路天線4〇所包 圍的表面上。所以，寄生微帶線42除了增加多頻帶天線 4之可支援的通訊頻段之外，並不需額外的容納空間，而 達成了手機多頻通訊功能及滿足輕薄性設計的目的。 此外，本發明之多頻帶天線於此設計下，仍保持良好 的通訊品質’請參閱圖五。圖五'纟會示圖四A之多頻帶天 線於不同頻率下的反射損耗(S11)。圖五之量測頻段涵蓋 0.5〜3GHz(亦即500〜3000MHz)，亦即涵蓋了手機常用通 訊頻段(GSM900、DCS、PCS、WCDMA)。於一般天線理 論中，越低的反射損耗(越小的S11之值)代表天線發射訊 號時，大部分的輸入的能量能夠被傳遞出去，只有小部份 的能量反彈回來’亦即代表較佳的通訊品質。因而，藉由 圖五之反射相耗曲線，可判斷本發明之多頻帶天線應用於 9 1376839 手機通訊的通訊品質 一般而言，反射損耗(S11)係以_4dB作為參考標準， 反射損耗低於-4dB代表可接受的通訊品質。請同^參閱 下列表一，表一列舉圖五中反射損耗(sn)低於_4dB &， 所涵蓋的頻率範圍及頻寬(涵蓋頻率範圍的最大值減去最 小值）。需補充說明的是，於此實施例中，圖四A及圖四 B中的多頻帶天線4所激發的三種共振模態頻率（第—共 振模態頻率、第二共振模態頻率及第三共振模態頻率 於圖五中的二個凹陷處之頻段。一般來說，第三共振模態 頻率對應GSM頻段，第一共振模態頻率及第二共振模態 頻率對應DCS/PCS/WCDMA頻段，此外，可適當地調^ 迴路微帶線40及寄生微帶線42的路徑長度，讓第一及第 二共振模態之頻率（圖五中頻率大於15GHz的兩個頻段 (凹陷處))較為接近’進而可增大涵蓋DCS/PCS/WCDMA 頰段的頻率範圍。 表一 厚度 涵蓋GSM900 的頻率範圍 _ (MHz) 頻寬 (MHz) 涵蓋 DCS/PCS/WCDMA 的頻率範圍(MHz) 頻寬 (MHz) 869〜1061 192 1663-2232 569 865-1030 165 1690-2210 520 873〜990 117 1700〜2312 612 —般來說，傳統天線所佔據體積的厚度為 r S3 10 8mm〜10mm。但是，如圖五所示，本發明之多頻帶天線4 所佔據體積的厚度d在4mm〜8mm時，於 GSM900(880〜960MHz) 、 DCS(1710~1880MHz)、 PCS(1850〜1990MHz)及 WCDMA(1920〜2170MHz)的規範 頻段之反射損耗都低於-4dB。甚至，由表一可知，本發明 之多頻帶天線4於厚度d為4mm時，具有良好通訊品質 (Sll < -4dB)的頻率範圍（873〜990MHz 及 1700〜2312MHz) 皆涵蓋了 GSM900、DCS、PTC及WCDMA的規範頻 段。因此，由圖五及表一可知，本發明之多頻帶天線4之 通訊頻段涵蓋了目前常見的無線通訊頻段，達成多頻通訊 功能。並且，本發明之多頻帶天線於每一個通訊頻段的反 射損耗都低於參考標準(-4dB) ’因而保持了良好的通訊品 質。 此外，請參閱圖六及圖七。圖六繪示圖四A中的多 頻帶天綠4於GSM900頻段下的訊號傳遞效率 (Efficiency)。圖七繪示圖四A之多頻帶天線4於 DCS/PCS/WCDMA頻段下的訊號傳遞效率。意義上，圖 /、及圖七之訊號傳遞效率與圖五之反射損耗是相對的。若 反射損耗大，代表大部分輸入天線的能量都反彈回來並未 傳遞出去，亦即訊號傳遞效率差，也代表天線的增益較 低。 一般來說，訊號傳遞效率達到40%以上代表良好的通 訊品質。如圖六及圖七所示，厚度4從8mm縮小至4mm 時，亦即天線之線路彼此之間越接近時，本發明之多頻帶 天線4於不同頻段内（GSM_、Dcs、pcs及wcdma) 1376839 的訊號傳遞效率皆能保持40%以上。因此，由圖六及圖七 之訊號傳遞效率曲線可知’本發明之多頻帶天線4於侷限 空間（厚度d = 8mm〜4mm)内，仍能保持良好的通訊品 質。 本發明不限於圖四A及圖四B所繪示之多頻帶天線 4的设計。請參閱圖八，圖八繪示本發明另一具體實施例 之多頻帶天線之示意圖。 # 相較於圖四B中的多頻帶天線4 ’圖八中的多頻帶天 線7之迴路微帶線7〇、寄生微帶線π及開路微帶線74 皆於兩個不平行（夾一角度）且互相連接的平面（第一平面 794及第二平面79〇)上延伸。此外，寄生微帶線72之第 一開路端720及開路微帶線74之第二開路端74〇皆於第 一平面794上延伸。迴路微帶線％之訊號饋入端7〇〇及 第了接地端702以及寄生微帶線72之第二接地端722皆 於第二平面79〇上延伸。雖然圖八中的多頻帶天線7之設 φ =不同於圖四A及圖四B中的多頻帶天線4之設計，但 疋激發的電磁輻射之共振模態頻率（或波長)取決於微帶線 的路徑長度，因此本發明之多頻帶天線可多元化設計線路 配置，並不侷限於圖四A、圖四B及圖八所繪示之設 計。 。 ，本發明之多頻帶天線之線路設計中寄生微帶線需被迴 =微帶線所包圍，且迴路微帶線及寄生微帶線之路徑長需 =別為二分之一波長及四分之一波長即可支援兩個通訊二 段。線路的形狀設計、彎曲角度或設置位置皆不受限。當 [S3 12 的路只需增加天線及調整新增天線 f曲角度。门樣也不Μ限於特定形狀、設置位置或 =於先前技術’本發明之多頻帶天線透過迴路微嫌 地且另路設計’且透過寄生微帶線一‘ C發的具有第-共振模態頻率的電磁輕射可 二使：生微帶線激發出第二共振模： ㈣▼天線不但增加了支援(接收及發射 =所額外佔據體積(寄生微帶線被迴路微 度可適當2路微帶線及寄生微.的路徑長 _率^二” ?近第一共振模態頻率及第二共振模 …可增加操作頻寬。總言之 =迴，包圍寄生微帶線的設計，能= »月匕且⑻於舰的容納空間内保持良好的通訊品質。 nit上較佳具體實施例之詳述，係希望能更加清楚 田，l又之特徵與精神，而並非以上述所揭露的較佳且 體實:例，明雜以限制。相反 希望此涵i各種改變及具辦制雜 =卿獅。因此，本發明所申請之專丄上 範可應該根據上述的說明作最寬廣的轉，以致使其涵蓋 所有可能的改變以及具相等性的安排。 13 •1376839 【圖式簡單說明】 圖一繪示傳統的單極天線之示意圖。 圖二繪示傳統的迴路天線之示意圖。 圖三繪示傳統的平面倒F型天線之示意圖。 圖四A繪示根據本發明一具體實施例之多頻帶天線 之示意圖。The multi-band antenna of the present invention excites two different resonant mode frequencies by means of a loop microstrip line surrounding the parasitic microstrip line design and through one end of the parasitic microstrip line grounded and the other end open. The electromagnetic radiation having the first resonant mode frequency excited by the loop microstrip line can be coupled to the parasitic microstrip, causing the parasitic microstrip line to excite the second resonant mode frequency. The multi-band antenna of the present invention not only increases the frequency of support (receiving and transmitting), but also requires additional occupied volume (the parasitic microstrip line is surrounded by the loop microstrip line). The path length of the re-invented loop microstrip line and the parasitic microstrip line can be properly and (4) limited to accommodate: =j communication function's attached God can be used in the field of machine communication by the following detailed description and [implementation] The multi-dense antenna of the invention can be mainly applied to the hand 6 1376839 to satisfy the multi-frequency communication function of the mobile phone. For example, the communication frequency band of the mobile phone is 810~960MHz, which is regulated by the Global System for Mobile Communications 900 (GSM 900), 1710~1880MHz, which is regulated by the Distributed Control System (DCS), and personal communication. Service (Personal Communiations Service, PCS) is defined by 1850~1990MHz and 1920~2170MHz as specified by Wideband Code Division Multiple Access (WCDMA). The multi-band antenna of the present invention mainly transmits a magnetic wave of different frequencies within a limited volume through a special microstrip line configuration and electromagnetic radiation coupling, and maintains good communication quality. How does the multi-band antenna of the present invention achieve the above results? Please refer to the following description of the embodiments. See Figure 4A and Figure 4B for clarity. 4A is a schematic diagram of a multi-band antenna 4 in accordance with an embodiment of the present invention. Figure 4B shows another perspective of the multi-band antenna 4 of Figure 4A. As shown in FIG. 4A and FIG. 4b, the multi-band antenna 4 of the present invention includes a loop microstrip line 40 and a parasitic microstrip line 42, and the loop microstrip line 40 and the parasitic microstrip line 42 are attached to the electrically insulated On the support body 49. The loop microstrip line 40 includes a signal feed end 400 and a first ground end 402 that extend and are attached to the second planar surface 490 of the support 49. The loop microstrip line 40 sequentially extends along the second plane 49〇, the third plane 492, and the first plane 494 from the signal feeding end 400, and sequentially along the first plane 494, the third plane 492, and the The second plane 490 extends to the first ground terminal 402, and the first ground terminal 402 is connected to the metal grounding member 48 to be grounded. r 1376839 - The parasitic microstrip line 42 includes a first ground terminal 422 that extends and is attached to the second plane _, and a first end Γ that extends and is attached to the _ plane example. The host microstrip line extends from the second ground end 422 sequentially to the third plane 492 to the first open end. The first ground end 422 is connected to the metal grounding member 48 for grounding. The path length from the signal feeding end 400 to the grounding terminal 4〇2 is two minutes. The path length of the open circuit end 42° to the second ground end 422 is the second signal line of the loop microstrip line 40. 4g (4), and there is a gap between the parasitic microstrip lines 40 (_, and the gap is not (four), the parasitic microstrip line 42 and the loop microstrip line 4 can be touched. The loop microstrip line 40 is excited by the = The electromagnetic radiation can be merged into the parasitic microstrip line &, so that the "band" line can excite the second resonant mode word in order to not input the ^. Where, the frequency band, the second resonant mode frequency is different from The first common permeable i-electromagnetic light-emitting two: = with: 匕 2 does not require signal input 'I: the resonant modal frequency of another frequency band. = 积上因Γ The circuit surrounded by the microstrip line Body volume) According to the extra line area (the signal of transmitting other communication frequencies without increasing the antenna occupied by the antenna, as shown in Figure 4 and Figure 4), the open microstrip line 44 packs ^ 8 = open The length of the path from the signal feeding end 400 to the second open end 440 is a quarter wavelength. The signal is input by the signal feeding end 400. In addition to flowing through the loop microstrip line 40, it can also flow through the open microstrip line 44, thus causing the open microstrip line 44 to excite a third resonant modal frequency. [To cover different communication bands, the third resonant mode The frequency is different from the second resonant mode frequency and the first resonant mode frequency. If the multi-band antenna of the present invention is placed in the mobile phone, the second surface 490 and the first surface 494 of the support body 49 respectively correspond to the front and back of the mobile phone 'Therefore the thickness d (equivalent to the distance between the front and back of the phone) affects the overall thickness of the phone. However, the thickness d is too small, and the lines between the antennas (for example, between the antenna and the metal grounding member 48) are easy. Interference caused by the thickness d being too large makes it difficult for the mobile phone to reduce the overall volume. As shown in Fig. 4a and Fig. 4B, the parasitic microstrip line 42 is disposed on the surface surrounded by the loop antenna 4〇. Therefore, the parasitic microstrip line 42 In addition to increasing the supportable communication band of the multi-band antenna 4, no additional accommodation space is required, and the multi-frequency communication function of the mobile phone and the design of the thin and light design are achieved. In addition, the multi-frequency of the present invention The antenna still maintains good communication quality under this design. Please refer to Figure 5. Figure 5 shows the reflection loss of the multi-band antenna of Figure 4A at different frequencies (S11). The measurement frequency band of Figure 5 covers 0.5. ~3GHz (that is, 500~3000MHz), which covers the common communication frequency bands of mobile phones (GSM900, DCS, PCS, WCDMA). In general antenna theory, the lower the reflection loss (the smaller the value of S11) represents the antenna transmission. In the signal, most of the input energy can be transmitted, and only a small part of the energy bounces back, which means better communication quality. Therefore, by the reflection phase loss curve of Figure 5, it can be judged that the invention is much Band antennas are used in 9 1376839. Communication quality of mobile communication In general, reflection loss (S11) is based on _4dB, and reflection loss below -4dB represents acceptable communication quality. Please refer to Table 1 below. Table 1 lists the reflection loss (sn) in Figure 5 below _4dB &, the range of frequencies covered and the bandwidth (covering the maximum value of the frequency range minus the minimum value). It should be noted that, in this embodiment, the three resonant mode frequencies (the first resonant mode frequency, the second resonant mode frequency, and the third excited by the multi-band antenna 4 in FIG. 4A and FIG. 4B are excited. The resonant mode frequency is in the frequency band of the two recesses in Figure 5. Generally, the third resonant mode frequency corresponds to the GSM band, and the first resonant mode frequency and the second resonant mode frequency correspond to the DCS/PCS/WCDMA band. In addition, the path lengths of the loop microstrip line 40 and the parasitic microstrip line 42 can be appropriately adjusted to allow the frequencies of the first and second resonant modes (the two frequencies (indentations) of the frequency greater than 15 GHz in FIG. 5) The frequency range covering the DCS/PCS/WCDMA buccal segment is increased. Table 1 thickness covers the frequency range of GSM900 _ (MHz) Bandwidth (MHz) Covers the frequency range (MHz) bandwidth of DCS/PCS/WCDMA (MHz) 869~1061 192 1663-2232 569 865-1030 165 1690-2210 520 873~990 117 1700~2312 612 In general, the thickness of the volume occupied by the conventional antenna is r S3 10 8mm~10mm. Figure 5 shows the volume occupied by the multi-band antenna 4 of the present invention. When the degree d is 4mm~8mm, the reflection loss in the normal frequency bands of GSM900 (880~960MHz), DCS (1710~1880MHz), PCS (1850~1990MHz) and WCDMA (1920~2170MHz) is lower than -4dB. Even, As can be seen from Table 1, the multi-band antenna 4 of the present invention has a good communication quality (Sll < -4 dB) in the frequency range (873 to 990 MHz and 1700 to 2312 MHz) when the thickness d is 4 mm, and covers GSM900, DCS, and PTC. And the standard frequency band of WCDMA. Therefore, as shown in FIG. 5 and Table 1, the communication frequency band of the multi-band antenna 4 of the present invention covers the currently common wireless communication frequency band, and achieves multi-frequency communication function. Moreover, the multi-band antenna of the present invention is The reflection loss of each communication band is lower than the reference standard (-4dB)' thus maintaining good communication quality. In addition, please refer to Figure 6 and Figure 7. Figure 6 shows the multi-band sky green 4 in Figure 4A. Signal transmission efficiency in the GSM900 band. Figure 7 shows the signal transmission efficiency of the multi-band antenna 4 of Figure 4A in the DCS/PCS/WCDMA band. In the sense, the signal transmission efficiency of Figure/, and Figure 7 is Figure 5 shows the reflection loss is relative If the reflection loss is large, the energy representing most of the input antennas bounces back and is not transmitted, that is, the signal transmission efficiency is poor, which means that the gain of the antenna is low. Generally speaking, the signal transmission efficiency of 40% or more represents good communication. quality. As shown in FIG. 6 and FIG. 7, when the thickness 4 is reduced from 8 mm to 4 mm, that is, the closer the antenna lines are to each other, the multi-band antenna 4 of the present invention is in different frequency bands (GSM_, Dcs, pcs, and wcdma). The signal transmission efficiency of 1376839 can be maintained above 40%. Therefore, from the signal transmission efficiency curves of Figs. 6 and 7, it can be seen that the multi-band antenna 4 of the present invention maintains good communication quality in a limited space (thickness d = 8 mm to 4 mm). The present invention is not limited to the design of the multi-band antenna 4 illustrated in Figures 4A and 4B. Referring to FIG. 8, FIG. 8 is a schematic diagram of a multi-band antenna according to another embodiment of the present invention. # Compared to the multi-band antenna 4 in Figure 4B, the loop microstrip line 7〇, the parasitic microstrip line π and the open microstrip line 74 of the multi-band antenna 7 in Figure 8 are both non-parallel (clip one) The planes (the first plane 794 and the second plane 79〇) extend over the mutually connected planes. In addition, the first open end 720 of the parasitic microstrip line 72 and the second open end 74 of the open microstrip line 74 extend over the first plane 794. The signal feed terminal 7A of the loop microstrip line % and the second ground terminal 722 of the ground strap 702 and the parasitic microstrip line 72 all extend over the second plane 79A. Although the multi-band antenna 7 in FIG. 8 is set to be different from the design of the multi-band antenna 4 in FIGS. 4A and 4B, the resonant mode frequency (or wavelength) of the xenon-excited electromagnetic radiation depends on the microstrip. The path length of the line, therefore, the multi-band antenna of the present invention can be designed in a variety of ways, and is not limited to the designs shown in FIG. 4A, FIG. 4B and FIG. . In the circuit design of the multi-band antenna of the present invention, the parasitic microstrip line needs to be surrounded by the back-microstrip line, and the path of the loop microstrip line and the parasitic microstrip line needs to be longer than one-half wavelength and four points. One wavelength can support two communication segments. The shape design, bending angle or setting position of the line is not limited. When [S3 12's way only needs to increase the antenna and adjust the new antenna f angle. The door is also not limited to a specific shape, set position or = in the prior art 'the multi-band antenna of the present invention passes through the circuit slightly and is designed separately' and has a first-resonance mode through the parasitic microstrip line The electromagnetic light of the frequency can be two: the microstrip line excites the second resonant mode: (4) ▼ The antenna not only increases the support (received and transmitted = the extra occupied volume) (the parasitic microstrip line is properly looped by the circuit 2) The length of the path with the line and the parasitic micro. _ rate ^ two" near the first resonant mode frequency and the second resonant mode ... can increase the operating bandwidth. In general = back, surrounded by parasitic microstrip line design, can = »月匕和(8) maintains good communication quality in the ship's accommodation space. The details of the preferred embodiment on nit are intended to clarify the characteristics and spirit of the field, not the above-mentioned disclosure. Good and practical: for example, it is limited by the restrictions. On the contrary, it is hoped that this change will be carried out and that it will be handled by the company. Therefore, the scope of the application of the present invention should be the broadest according to the above description. So that it covers all possible changes and Arrangement of Equivalence 13 • 1376839 [Simplified Schematic] Figure 1 shows a schematic diagram of a conventional monopole antenna. Figure 2 shows a schematic diagram of a conventional loop antenna. Figure 3 shows a schematic diagram of a conventional planar inverted-F antenna. FIG. 4A is a schematic diagram of a multi-band antenna according to an embodiment of the invention.
圖四B繪示圖四A中的多頻帶天線之另一視角。 圖五繪示圖四A中的多頻帶天線於不同頻率下的反 射損耗。 圖六繪示圖四A中的多頻帶天線於GSM900頻段下 的訊號傳遞效率。 圖七繪示圖四 A 中的多頻帶天線於 DCS/PCS/WCDMA頻段下的訊號傳遞效率。 圖八繪示根據本發明另一具體實施例之多頻帶天線之 不意圖。 【主要元件符號說明】 1 :單極天線 2 :迴路天線 3 :平面倒F型天線 12、34 :開路端 1376839 22、32 :接地端 10、20、30、400、700 : 40、70 :迴路微帶線 44、74 :開路微帶線 420、720 :第一開路端 440、740 :第二開路端 490、790 :第二表面 494、794 :第一表面 d :厚度 4、7 :多頻帶天線 訊號饋入端 42、72 :寄生微帶線 402、702 :第一接地端 422、722 :第二接地端 49 :支撐體 492 :第三表面 48 :金屬接地件FIG. 4B illustrates another perspective of the multi-band antenna of FIG. 4A. Figure 5 is a graph showing the reflection loss of the multi-band antenna of Figure 4A at different frequencies. Figure 6 is a diagram showing the signal transmission efficiency of the multi-band antenna in Figure 4A in the GSM900 band. Figure 7 shows the signal transmission efficiency of the multi-band antenna in Figure 4A in the DCS/PCS/WCDMA band. Figure 8 is a schematic illustration of a multi-band antenna in accordance with another embodiment of the present invention. [Main component symbol description] 1 : Monopole antenna 2 : Loop antenna 3 : Planar inverted F antenna 12 , 34 : Open end 1376839 22, 32 : Ground terminal 10, 20, 30, 400, 700 : 40, 70 : Circuit Microstrip lines 44, 74: open microstrip lines 420, 720: first open ends 440, 740: second open ends 490, 790: second surface 494, 794: first surface d: thickness 4, 7: multi-band Antenna signal feed terminals 42, 72: parasitic microstrip lines 402, 702: first ground terminal 422, 722: second ground terminal 49: support body 492: third surface 48: metal grounding member
[S] 15[S] 15