201025725 九、發明說明： 【發明所屬之技術領域】 本發明係有關一種平板天線，尤指一種縮小化之圓極 化平板天線。 【先前技術】 隨著無線通訊的發展’車用衛星導航系統因此迅速掀 起風潮’除了車用部分以外，也發展出如手機、筆記型電 腦、個人導航系統等多種全球衛星定位系統（GPS)產品， 諸如此類的產品都是使用圓極化訊號做為傳輸。 由於設計一個圓極化天線需滿足在同一頻率激發兩個 互相垂直之極化分量、使得兩分量振幅相等且相位相差9〇 度。傳統天線遵照此觀念設計下，以玻纖板為例，尺寸大 致為50 X 50min2 ’為方便於應用必須達到縮小尺寸之目的 。為了滿足現今產品講究輕薄短小的目標，要將全球衛星 疋位系統（GPS)整合於產品時，會導致現有天線無法裝置 於產品内部有限之使用空間，因此天線必須越做越小。一 般圓極化天線縮小化的設計方式有以植入槽孔於輻射片上 來改變電流路徑，再者使用被動元件，如晶片電阻、晶片 電容也可以達到縮小尺寸的功效，然而這些方式縮小幅度 乾圍有限。 因此’本發明提出一種具有電容性饋入之圓形極化平 板天線’本天線可操作於全球衛星定位系統(GPS) 1575 MHz 且具有良好圓.極化特性，同時達到尺寸縮小之目的。 201025725 【發明内容】 本發明所提出的具有電容性饋入之圓極化平板天線竿 構，包含：-基底、輕射部、接地部、饋入電極、饋入ς ，該基底為介電材料，具有一第—表面及一相對於該第一 表面之第二表面及大致垂直於該第一表面與該第二^面之 ❹-側面，同時具有—貫穿基底之貫孔。純射部含一 本體及複數個可調支臂與該本體相互連接，其中該本體形 成於第-表面並具有一開孔，而該開孔環繞並包圍該基底 ，貫孔。該接地部，形成於該基底第二表面。該饋^極 二该輻射部之間具有一小於5 _之環狀非導通區間，而該 環狀區間即為電容性饋入之搞合間隙。該饋入璋大致配置 於該貫孔中，具有-起始端及一末端，該起使端連接至一 =號源，而該末端電氣連接至該饋人電極，同時該饋 _ 與該接地面呈不導通狀態。 本發明主要在於與輻射部之本體相連接之複數個可調 ^臂。藉由調整該可調支臂長度或面積，可以達成天線縮 ^化且#作於全球衛星定位系統（Gps)中心頻率約為郎 Hz並使得本發明具有良好的圓極化特性。 【實施方式】 兹有關本發明之技術内容及詳細說明’現配合圖示說 =如下：請參閱第-圖，係本發明之圓極化平板天線外觀 立體不意圖。如圖所示：在圖示中所展露的為一種縮小化 8 201025725201025725 IX. INSTRUCTIONS: [Technical Field] The present invention relates to a panel antenna, and more particularly to a reduced rounded planar antenna. [Prior Art] With the development of wireless communication, the "vehicle satellite navigation system has quickly set off a wave". In addition to the vehicle parts, various global satellite positioning system (GPS) products such as mobile phones, notebook computers, and personal navigation systems have also been developed. Products such as these use circularly polarized signals for transmission. Since designing a circularly polarized antenna is required to excite two mutually perpendicular polarization components at the same frequency, the two components have equal amplitudes and phase differences of 9 degrees. Conventional antennas are designed according to this concept. For example, in the case of a fiberglass board, the size is as large as 50 X 50 min2 ’ for the purpose of reducing the size for the application. In order to meet the current short-term and short-term goal of products, the integration of the global satellite clamp system (GPS) into the product will result in the existing antenna not being able to be installed in the limited space of the product, so the antenna must be smaller and smaller. Generally, the design of the circularly polarized antenna is reduced by implanting the slot on the radiating plate to change the current path, and the passive component, such as the chip resistor and the chip capacitor, can also achieve the effect of downsizing, but these methods reduce the amplitude. Limited. Therefore, the present invention proposes a circularly polarized planar antenna having capacitive feeding. The present antenna is operable at a global satellite positioning system (GPS) of 1575 MHz and has good circular polarization characteristics while achieving downsizing. 201025725 SUMMARY OF THE INVENTION The present invention provides a circularly-polarized planar antenna structure with capacitive feeding, comprising: a substrate, a light-emitting portion, a grounding portion, a feeding electrode, and a feeding port, wherein the substrate is a dielectric material. And having a first surface and a second surface opposite to the first surface and substantially perpendicular to the first surface and the second surface of the second surface, and having a through hole extending through the substrate. The pure shot portion includes a body and a plurality of adjustable arms connected to the body, wherein the body is formed on the first surface and has an opening, and the opening surrounds and surrounds the base and the through hole. The ground portion is formed on the second surface of the substrate. The feeding electrode has an annular non-conducting interval of less than 5 _ between the radiating portions, and the annular interval is a fitting gap of the capacitive feeding. The feed port is disposed substantially in the through hole, has a start end and an end, the start end is connected to a source, and the end is electrically connected to the feed electrode, and the feed and the ground plane It is not conductive. The invention resides primarily in a plurality of adjustable arms that are coupled to the body of the radiating portion. By adjusting the length or area of the adjustable arm, the antenna reduction can be achieved and the center frequency of the global satellite positioning system (Gps) is about lang Hz and the invention has good circular polarization characteristics. [Embodiment] The technical content and detailed description of the present invention will now be described as follows: Referring to the drawings, the appearance of the circularly polarized panel antenna of the present invention is not intended. As shown in the figure: what is shown in the illustration is a reduction 8 201025725
且具有電容性饋入之圓極化平板天線，包括有：一基底13 、一輻射部14、一接地部15、一饋入電極16及一饋入埠17 。該基底13為介電材料，其上具有一第一表面丨31及一相 對於弟一表面131之第二表面132及大致垂直於該第一表 面131與該第二表面132之一側面133 ，同時具有貫穿基 底之貫孔134。該輻射部14，有一本體141 ，形成於第一 表面131且具有一開孔142，其環繞並包圍該貫孔134， 及與該本體141連接之四個可調支臂143、144、145、 146。該接地部15，形成於該基底η之第二表面I%，而 罪近該貫孔134處具有一非導通區塊151。該饋入電極16 ，位於該第一表面131之貫孔134處，同時該饋入電極Μ 與該輻射部之本體141之間具有一小於5_之環狀非導通 區間161 ，而該環狀區間161即為電容性饋入之耦合間隙 。該饋入埠17，大致配置於該貫孔134中，具 m及一末端m，該起始端m連接至—訊號源， 而"亥末端172電氣連接至該饋入電極16，同時該饋入埠口 與該接地部15呈不導通狀態。 堉翏閱第 一 Ά 圃 你尽發明之圓極化平板天線上 2側視示意圖。如圖所示：從圖示中該圓極化平板天線 广，該_之本體141的開孔142環繞該饋入電極 非導通區間161，且該輻射部之本體141的邊 緣延伸出四個可調支臂143、144、 纲敕Υ ___ J 丄46 。而藉由 3周整该可調支臂143、144、145 e ^ Λα J£ , 45、l46之長度，可有效 S加共振路徑而降低共振頻率 9 201025725 請參閱第三、四圖，係本發明之圓極化平板天線量測 返回損失圖（Return Loss)與量測史密斯圖（Smith Chart)。由上 述返回損失量測結果顯示本發明天線適用於全球衛星定位 系統（GPS)中心頻率約為1575 MHz且以電壓駐波比2:1所 定義之阻抗頻寬約從1566 MHz至1581 MHz，而由量測史密 斯圖可以發現阻抗呈現圓極化雙共振的現象。 ® 請參閱第五、六及七圖，係本發明之圓極化平板天線 量測軸比圖（Axial Ratio)及圓極化平板天線二維量測場型圖 。從實驗結果得知全球衛星定位系統(GPS) 1575 MHz之模態 落於3 dB軸比頻寬内，且由量測圓極化場型得知本發明天 線具有良好的半功率束徑寬。因此本發明圓極化平板天線 具有良好之圓極化輻射特性。 請參閱第八、九圖，為本發明圓極化平板天線之其他 實施例示意圖。在圖八中，該輻射部之本體141為方形， ® 並具有一狹縫88，該狹縫88由輻射部之本體141邊緣向内 延伸。藉由加入該狹縫88可調整圓極化波之共振頻率，使 得全球衛星定位系統(GPS) 1575 MHz之模態阻抗匹配落於史 密斯圖之2:1 VSWR的等阻抗圓内。在圖九中，該輻射部之 本體141為方形，且具有兩截角99。藉由加入該截角99可 調整圓極化波之水平與垂直極化之振幅以及相位，使得本 發明天線於全球衛星定位系統(GPS) 1575 MHz獲得更良好的 軸比頻寬。上述之其他實施例樣式均可得到較佳之圓極化 輻射場型。 201025725 【圖式簡單說明】 第一圖係本發明之圓極化平板天線外觀立體示意圖。 第二A、B圖係本發明之圓極化平板天線上視及側視示意 圖。 第三圖係本發明之圓極化平板天線量測返回損失圖（Return Loss)。 第四圖係本發明之圓極化平板天線量測史密斯圖（Smith Chart)。 第五圖係本發明之圓極化平板天線量測軸比圖（Axial Ratio) ο 第六圖係本發明之圓極化平板天線在ΧΖ平面之二維量測 場型圖。 第七圖係本發明之圓極化平板天線在ΥΖ平面之二維量測 場型圖。 第八圖係本發明之圓極化平板天線之第一其它實施例示意 圖。 第九圖係本發明之圓極化平板天線之第二其它實施例示意 【主要元件符號說明】 13 :基底 131 :第一表面 132 :第二表面 133_ :側面 134 :貫孔 14 :輻射部 141 :本體 142 :開孔 201025725 143、144、145、146 :可調支臂 15 :接地部 151 :非導通區塊 16 :饋入電極 161 :環狀非導通區間 17 :饋入谭 © 171 :起始端 172 ··末端 173 ·訊號源 88 :狹缝 99 :截角The circularly polarized panel antenna with capacitive feeding includes a substrate 13, a radiating portion 14, a grounding portion 15, a feeding electrode 16, and a feeding port. The substrate 13 is a dielectric material having a first surface 丨 31 and a second surface 132 opposite to the first surface 131 and a side 133 substantially perpendicular to the first surface 131 and the second surface 132. At the same time, there is a through hole 134 penetrating the base. The radiant portion 14 has a body 141 formed on the first surface 131 and having an opening 142 surrounding and surrounding the through hole 134, and four adjustable arms 143, 144, 145 connected to the body 141. 146. The grounding portion 15 is formed on the second surface I% of the substrate η, and has a non-conducting block 151 near the through hole 134. The feeding electrode 16 is located at the through hole 134 of the first surface 131, and the feeding electrode Μ and the body 141 of the radiating portion have an annular non-conducting interval 161 of less than 5 mm, and the ring The interval 161 is the coupling gap of the capacitive feed. The feed port 17 is disposed substantially in the through hole 134, having m and an end m, the start end m is connected to the signal source, and the "Hei end 172 is electrically connected to the feed electrode 16, and the feed The inlet port and the grounding portion 15 are in a non-conducting state. See the first Ά 圃 2 side view of the circularly polarized panel antenna you have invented. As shown in the figure, the circularly polarized panel antenna is wide in the figure, the opening 142 of the body 141 surrounds the feeding electrode non-conducting section 161, and the edge of the body 141 of the radiating portion extends four The arm 143, 144, ___ J 丄 46. By adjusting the length of the adjustable arms 143, 144, 145 e ^ Λ α J £ , 45, and l46 for 3 weeks, the resonance path can be effectively increased by S to reduce the resonance frequency. 9 201025725 Please refer to the third and fourth figures. The invention discloses a circularly polarized panel antenna measuring Return Loss and measuring Smith Chart. The above return loss measurement results show that the antenna of the present invention is suitable for a global positioning system (GPS) center frequency of about 1575 MHz and an impedance bandwidth defined by a voltage standing wave ratio of 2:1 is about 1566 MHz to 1581 MHz, and From the measurement of the Smith chart, it can be found that the impedance exhibits a circularly polarized double resonance phenomenon. ® Refer to Figures 5, 6 and 7. This is the two-dimensional measurement field diagram of the circularly polarized panel antenna of the present invention and the circularly polarized panel antenna. It is known from the experimental results that the global satellite positioning system (GPS) 1575 MHz mode falls within the 3 dB axial ratio bandwidth, and the measured circular polarization field type shows that the antenna of the present invention has a good half power beam diameter. Therefore, the circularly polarized panel antenna of the present invention has good circularly polarized radiation characteristics. Please refer to the eighth and ninth figures, which are schematic diagrams of other embodiments of the circularly polarized panel antenna of the present invention. In Fig. 8, the body 141 of the radiating portion is square, and has a slit 88 extending inwardly from the edge of the body 141 of the radiating portion. By adding this slit 88, the resonant frequency of the circularly polarized wave can be adjusted so that the modal impedance matching of the Global Positioning System (GPS) 1575 MHz falls within the equal impedance circle of the 2:1 VSWR of the Smith chart. In Fig. 9, the body 141 of the radiating portion is square and has two truncated angles 99. By adding the truncated angle 99, the amplitude and phase of the circularly polarized wave can be adjusted to the horizontal and vertical polarization, so that the antenna of the present invention achieves a better axial ratio bandwidth at the Global Positioning System (GPS) 1575 MHz. The preferred embodiment of the above embodiments provides a preferred circularly polarized radiation pattern. 201025725 [Simplified description of the drawings] The first figure is a perspective view of the appearance of the circularly polarized planar antenna of the present invention. The second A and B drawings are schematic and side views of the circularly polarized panel antenna of the present invention. The third figure is a Return Loss of the circularly polarized panel antenna of the present invention. The fourth figure is a Smith Chart of the circularly polarized panel antenna of the present invention. The fifth figure is an Axial Ratio of the circularly polarized panel antenna of the present invention. The sixth figure is a two-dimensional measurement field diagram of the circularly polarized panel antenna of the present invention in the pupil plane. The seventh figure is a two-dimensional measurement field diagram of the circularly polarized panel antenna of the present invention in the pupil plane. Figure 8 is a schematic view of a first other embodiment of a circularly polarized panel antenna of the present invention. The ninth drawing is a schematic diagram of a second other embodiment of the circularly polarized panel antenna of the present invention. [Main component symbol description] 13: Substrate 131: First surface 132: Second surface 133_: Side surface 134: Through hole 14: Radiation portion 141 : Body 142 : Opening 201025725 143, 144, 145, 146 : Adjustable arm 15 : Grounding portion 151 : Non-conducting block 16 : Feeding electrode 161 : Annular non-conducting section 17 : Feeding in Tan © 171 : Start 172 ··End 173 ·Source 88: Slit 99: Truncation
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