A7 —------- - B7 五、發明說明（1) 雙頻微帶天線的設計是微帶天線研究上的重要課題之 :’相關的研究也相當多，包含使用晶片電阻、電容之微 π天線π又计被f天線加上寄生金屬片（卿狀丨如她⑻設 计、利用槽孔(slot)或狹孔(slit)等等。這些設計通常是利用 兩個被激發的操作模態具有相似的表面電流分佈，使得兩 個操作頻率具有相似的輻射特性；不過這此雙頻微帶天線 設計的操作頻寬往往綠滿足實際無線通訊系統的:求氣 在應用上有許多限制。在本發明中，我們提出一種適用於 無線區域網路的雙頻微帶天線，其操作頻寬可以達到實際 應用的需求。同時’本發明天線的—種實施例，其基底 (substrate)層是仙高麟共对αΐ7公分的多層複合基 底結構’比較起來仍保留微帶天線低姿勢一卿趾)的優 點’同時製作上相當方便，極具有產業利用性之實用目的， 故提出專利申請。 、第1圖所示為本發明天線的一種實施例:在半徑為228 Α刀的圓形輻射金屬片中植入一個開口環狀槽孔，此開口 =狀槽孔之半徑是L2公分、寬度是⑽5公分，為了使得 雙頻微帶天_兩_作㈣能同時獲得輸人阻抗的匹 配’此開口環狀槽孔的圓心是在沿h軸偏移原先圓形輻 射金屬片圓心的〇.4公分處，且此開口環狀槽孔的開口處 有〇.4么为大小。此時，天線的第—(較低)及第二(較高)操 作頻率’由圓形鋪金屬片及開口環狀槽孔賴成之較小 圓形金屬片所控制’且決定於此兩姻帛射金屬片的最低共 504866 A7 B7 經濟部中央標準局員工消費合作社印製 五、發明說明（2) " —' 振模態。此外，本項天線設計的結構是採祕薄的複合基 底層結構（見圖1)，此結構總共有三層，最上層厚度為_ 公分，最底層厚度為〇.〇8公分，使用的同是相對 數 為4.4的玻、纖板，*中間是空氣層(以非導電性支柱支撐於 其他兩層介質層之間），其總共厚度似17公分，較不佔空 間。事實上要達到足夠的頻寬，除了上述之三層的複合基 底結構外，也可騎慮使用兩層不同材質的複合基底結 構，或是採用單-層的空氣或是介電係數較低的材質來當 基底層。 圖1實施例的相關實驗結果於圖2及圖3表示，圖2 所示為本項天線料的返娜失(她m丨㈣實驗測量結 果。天線的設計參數列於圖2之圖式說明。由1:2 5 vswr 所定義之操作頻寬’以及參考下頁表卜我們可以得到在 雙頻操作的第-操作頻率2440 MHz處有9〇廳的頻寬 (2395至2485 MHz) ’或者是3.7% (對應於中心頻率244〇 MHz) ’在雙頻操作的第二操作頻率523〇 MHz處有· MHz的頻寬(ΜΗ)至535〇 MHz)，或者是4 6% (對應於中 心頻率5230 MHz)。在頻寬上，這兩個頻段的操作頻寬均 符合且適用於2.4及2.5 GHz無線區域網路應用的要求。圖 3所示則為本項天線設計的輕射場型㈣㈣加帅㈣實驗 量測結果，實驗結果可知本項天線設計於操作頻寬内的輕 射特性相當好’其中這兩個被激發的雙頻操作模態，都是 垂向(broadside)的輕射場型，且具有相同的輕射極化面。而 "^氏張尺度適用中國國家標準（CNS) Α4^Γ(210x297^1)-~----- 請 先 閱 讀 背 δ 注 意1· 填 寫 本 頁 裝 線 A7 B7 五、發明說明（3) 本項天線設計的天線增益(gain)實驗量測結果如表丨所示， 由這實驗結果可知本項天線設計的天線增益在這兩個被激 發的雙頻操作模態下，天線增益的變化很小且在1 dBi以 内0 表1 :圖1實施例的操作頻寬及天線增益 頻率 (MHz) 阻抗頻寬 (MHz, %) 天線增益 (dBi) f； =2440 90, 3.7 2.9 f2 = 5230 240, 4.6 1.9 本發明的其他實施例如第4圖所示，在此設計結構中， 使用的是一矩形輻射金屬片，以前述的設計原理，也可以 得到適用於2.4及5.2 GHz無線區域網路應用的雙頻微帶天 線。 本發明中所敘述的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。 [圖式說明] 第1圖為本發明之一種適用於無線區域網路的雙頻微帶天 線之結構圖，在其圓形輻射金屬片（1)内植入一個開口環狀 _槽孔(2)，此槽孔包圍一較小的圓形輻射金屬片（11);圓形 度適时關家鮮（CNS) A4規格（21gx297公爱5--- A7 B7 五、發明說明（4) 輕射金屬片製作在一個接地的複合基底層上面，此基底之 材質最上層(3)與最下層(4)是玻纖，而中間是空氣層(5)，同 軸線饋入(6)穿過接地金屬片（7)及複合基底層且與圓形輻 射金屬片連接。 第2圖為第1圖天線的返回損失實驗測量結果。圓形輻射金 屬片半徑為2·28公分，其内植入有一個開口環狀槽孔，此 開口環狀槽孔半徑為1·2公分、寬度為〇 〇5公分，開口寬度 則為0·4公分，其圓心離圓形輻射金屬片圓心〇·4公分，而饋 入點離圓形輻射金屬片圓心〇12公分，其中複合基底層之 最上層與最下層材質其厚度、相對介電常數分別為0.04公 分、4.4及0·08公分、4·4，大小為75公分χ75公分，中間則 為空氣層，其厚度為0 05公分。 第3圖為第1圖天線的輻射場型實驗量測結果。粗線代表主 極化（co-polarization)測量結果，細線代表交叉極化 (cr〇SS_p〇larization)測量結果；⑴為天線操作在244〇MHz之 兩垂直平面測量結果，（2)為天線操作在523〇 MHzi兩垂直 平面測置結果。天線參數如圖2說明中所示。 第4圖為本發明天線的其他實施結構圖：在矩形輻射金屬片 (41)内植入一個矩形環狀的開口槽孔(42);基底層(犯)使用 單一層的空氣或是介電係數較低的材質；同軸線饋入(46) 穿過接地金屬片(47)及基底層與矩形輻射金屬片連接。 尺度適用中國國家標準（CNS) A4規^--- 請 先 閱 讀 背A7 —--------B7 V. Description of the invention (1) The design of dual-band microstrip antennas is an important topic in the research of microstrip antennas: 'Related research is also quite extensive, including the use of chip resistors and capacitors. The small π antenna π is also counted by the f antenna plus a parasitic metal sheet (such as her design, using slots or slits, etc. These designs usually use two excited The operating modes have similar surface current distributions, making the two operating frequencies have similar radiation characteristics; however, the operating bandwidth of this dual-band microstrip antenna design is often green to meet the actual wireless communication system: Qiqi has many applications Limitation. In the present invention, we propose a dual-band microstrip antenna suitable for wireless local area networks, whose operating bandwidth can meet the needs of practical applications. At the same time, an embodiment of the antenna of the present invention, its substrate The layer is a multi-layer composite base structure with a total height of αΐ7 cm by Xian Gao Lin. 'Compared to the advantages of the microstrip antenna (low posture and low toe), it is also very convenient to manufacture and has practical industrial purposes. A patent application. Figure 1 shows an embodiment of the antenna of the present invention: an open annular slot is implanted in a circular radiating metal sheet with a radius of 228 A, and the radius of this opening = shaped slot is L2 cm and the width It is ⑽5 cm. In order to make the dual-frequency microstrip antenna _ two _ work at the same time to obtain the input impedance matching 'The center of this open annular slot is offset from the center of the original circular radiating metal sheet along the h axis. 4 centimeters, and the opening of the opening circular slot is 0.4 mm in size. At this time, the first (lower) and second (higher) operating frequencies of the antenna are 'controlled by the circular metal sheet and the smaller circular metal sheet formed by the open circular slot hole' and are determined by these two A minimum of 504,866 fired metal sheets are printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs. 5. Description of Invention (2) " — 'vibration mode. In addition, the structure of this antenna design is a thin composite base layer structure (see Figure 1). This structure has a total of three layers, the top layer thickness is _ cm, and the bottom layer thickness is 0.08 cm. The same is used The relative number of glass and fiberboard is 4.4. The middle layer is an air layer (supported by non-conductive pillars between the other two dielectric layers). The total thickness is 17 cm, which takes up less space. In fact, to achieve sufficient bandwidth, in addition to the three-layer composite base structure described above, it is also possible to consider using two layers of composite base structures of different materials, or using single-layer air or a lower dielectric constant. The material comes as the base layer. The relevant experimental results of the embodiment of FIG. 1 are shown in FIG. 2 and FIG. 3. FIG. 2 shows the measurement results of this antenna material. The design parameters of the antenna are listed in the diagram of FIG. 2. .The operating bandwidth defined by 1: 2 5 vswr 'and referring to the table on the next page, we can get the bandwidth of 90 square meters (2395 to 2485 MHz) at the-operating frequency of 2440 MHz for dual-frequency operation. It is 3.7% (corresponding to the center frequency of 2440MHz) 'There is a bandwidth of (MHz) to 5350MHz at the second operating frequency of 5230MHz for dual-frequency operation, or 4 6% (corresponding to the center 5230 MHz). In terms of bandwidth, the operating bandwidth of these two bands is in line with the requirements of 2.4 and 2.5 GHz wireless LAN applications. Figure 3 shows the measurement results of the light field type and handsome test designed for this antenna. The experimental results show that the light emission characteristics of this antenna designed in the operating bandwidth are quite good. The frequency operation modes are all broadside light emission field types, and have the same light emission polarization plane. The "^" Zhang scale is applicable to the Chinese National Standard (CNS) Α4 ^ Γ (210x297 ^ 1)-~ ----- Please read the back δ Note 1 · Fill in this page A7 B7 Fifth, the description of the invention (3 ) The experimental measurement results of the antenna gain of this antenna design are shown in Table 丨. From the experimental results, it can be known that the antenna gain of this antenna design under these two excited dual-frequency operation modes, The change is small and within 1 dBi. Table 1: The operating bandwidth and antenna gain frequency (MHz) in the embodiment of Figure 1 impedance bandwidth (MHz,%) antenna gain (dBi) f; = 2440 90, 3.7 2.9 f2 = 5230 240, 4.6 1.9 Other embodiments of the present invention are shown in Fig. 4. In this design structure, a rectangular radiating metal sheet is used. Based on the aforementioned design principles, it can also be applied to 2.4 and 5.2 GHz wireless local area networks. Dual-band microstrip antenna for road applications. The embodiments described in the present invention 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. [Schematic description] Figure 1 is a structural diagram of a dual-band microstrip antenna suitable for wireless local area network in the present invention. An open ring-shaped slot (a slot) is implanted in its circular radiating metal sheet (1). 2), this slot surrounds a small circular radiant metal sheet (11); circularity is in good time (CNS) A4 size (21gx297 public love 5--A7 B7 V. Description of the invention (4) The light-emitting metal sheet is made on a grounded composite base layer. The material of this base is the top layer (3) and the bottom layer (4) are glass fiber, and the middle is the air layer (5). It passes through the grounded metal sheet (7) and the composite base layer and is connected to the circular radiation metal sheet. Figure 2 is the experimental measurement result of the return loss of the antenna in Figure 1. The radius of the circular radiation metal sheet is 2.28 cm, and its internal implantation There is an open annular slot. The radius of this open annular slot is 1.2 cm, the width is 0.05 cm, and the width of the opening is 0.4 cm. The center of the open slot is 0.4. Cm, and the feed point is 12 cm away from the center of the circular radiating metal sheet. The thickness of the top and bottom materials of the composite base layer, The dielectric constants are 0.04 cm, 4.4 and 0.08 cm, 4 · 4, with a size of 75 cm x 75 cm, with an air layer in the middle and a thickness of 0 05 cm. Figure 3 shows the radiation of the antenna in Figure 1. Field-type experimental measurement results. The thick line represents the measurement result of main polarization (co-polarization), and the thin line represents the measurement result of cross polarization (cr0SS_p〇larization); ⑴ is the measurement result of two vertical planes of the antenna operating at 2440MHz. (2) is the measurement result of the antenna operating in two vertical planes at 5230 MHz. The antenna parameters are shown in the description of Figure 2. Figure 4 is another structural diagram of the antenna of the present invention: in the rectangular radiating metal sheet (41) Insert a rectangular ring-shaped opening slot (42); the base layer (criminal) uses a single layer of air or a material with a lower dielectric constant; the coaxial wire feed (46) passes through the ground metal sheet (47) and The base layer is connected to a rectangular radiating metal sheet. The dimensions are applicable to the Chinese National Standard (CNS) A4 regulations ^ --- Please read the back first
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504866 經濟部中央標準局員工消費合作社印製 ' A7 B7 五、發明說明（5) [圖式簡單說明] 第1圖為本發明天線的一種實施結構圖。 第2圖為第1圖天線的返回損失實驗結果。 第3圖為第1圖天線的輻射場型實驗結果。 第4圖為本發明天線的其他實例結構圖。 本紙張尺度適用中國國家標準（CNS) A4規格（210x297公釐）504866 Printed by the Consumer Cooperatives of the Central Bureau of Standards of the Ministry of Economic Affairs A7 B7 V. Description of the invention (5) [Simplified illustration of the drawing] Figure 1 is an implementation structure diagram of the antenna of the present invention. Figure 2 shows the experimental results of the return loss of the antenna in Figure 1. Fig. 3 is the radiation field experiment results of the antenna of Fig. 1. FIG. 4 is a structural diagram of another example of the antenna of the present invention. This paper size applies to China National Standard (CNS) A4 (210x297 mm)