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Mutations in Surface and Overlapping Polymerase Gene Region of Hepatitis B virus and Risk of Hepatocellular Carcinoma: A Nested Case-Control Study
No full text背景：HBV病毒因子與肝細胞癌的關係近年來著重在HBV DNA與基因型層面。本研究目的在利用重疊病例對照研究分析病例和對照組在PreS/S及其和P基因重疊區域各點核苷酸變異分佈的情形，同時考慮基因型的影響。方法：研究個案來自一個1988-1992年間收案之男性HBV帶原者世代，對照組是依照病例進入研究年齡及血液採檢時間進行個別匹配，共計86名病例和125名對照進入分析。對於追蹤期間的血液檢體分析，是選擇病例發病兩年內之血液檢體，對照則取與病例檢體距離最近時點之血液檢體分析，共計17名病例與27名對照個案。結果：以adw為參考序列和對照組基線血液檢體分析結果進行比對，發現8個頻率在20%以上的變異型，包括PreS1區的2989C、3050T、3097A、3174T、PreS2區35A、S區的285A、529G、586C。B基因型序列大多數位置之核苷酸型態和adw序列一致，只有在A2989C、C3050T、C3174T與S區的A529G處具有盛行率在20%以上的變異型。基因型C在整段序列的許多位置，均具有盛行率在20%以上的變異型，尤其在PreS2和S基因區域nt 85-nt 598，變異型頻率可達50%以上，病例組和對照組在頻率分佈上具顯著差異的位置到處可見，高差異區主要分布在PreS2的nt 76-nt 147處，顯著差異位置包括A76C、G85A、G87A、C93T、A96C、A99C 、T105C、T109A和G110C，變異型頻率差異在15.3%-30.40%。這些病例和對照組具顯著差異的位置對B基因型者而言，變異型的頻率均在6.3%以下，但對C基因型者而言，變異型頻率均介於37.1%-62.9%，因此再單就C基因型者分析這些核苷酸位置變異和HCC的關係，結果發現在nt 76-nt 110及nt 619處與HCC仍舊具有邊緣性統計相關。分析兩時點間序列的差異，發現大部分位置均處穩定狀態，只有nt 2898、nt 3174和nt 529具有大於20%以上的突變率。結論：B基因型大致反映adw序列，而C基因型病毒序列在各核苷酸位置和adw序列比較具較多變異。HBV PreS/S及與其重疊P基因區，各核苷酸位置在追蹤期間大致處於相當穩定狀態，以adw為參考序列，病例與對照組比較具變異型頻率較高，且分散在全區域，但高差異區集中在PreS2 區nt 76-nt 110處，和已知〝a〞determinant區域重疊。Background and Aim: Variations in the viral genome of hepatitis B virus (HBV) has been associated with the clinical outcome of chronic HBV infection, but the significance of these variations in the development of hepatocellular carcinoma (HCC) remains largely unknown. The aim of this study was to longitudinally analyze the nucleotide variations in the PreS/S and overlapping P gene regions of the HBV genome and HCC risk.
Materials and Methods: Direct sequencing of HBV gene was performed on plasma samples from 86 cases and 125 controls nested within a cohort of HBV male carriers recruited between 1988-1992. Controls were matched with cases on the age of entering the study and the time of collection of blood samples at baseline. We also performed sequencing of the HBV gene in plasma samples collected from a total of 17 cases and 27 controls during follow-up. At the second time point, for cases, blood samples collected within two years before the onset of HCC were used. For controls, measuring time was selected according to the nearest blood collecting time of cases.
Results: Compared with adw as the reference sequence, 8 variants were found to have a frequency of ≧ 20% including 2989C, 3050T, 3097A, 3174T in PreS1 region, 35A in PreS2 region, and 285A, 529G, 586C in S region, at baseline samples of controls, the sequence of genotype B was mostly consistent with the adw sequence, except A2989C, C3050T, C3174T and A529G, which occurred at frequency of ≧ 20%. For genotype C, many positions in S region had variant types with prevalence ≧ 20%, especially at nt 85-nt 598 in PreS/S region, the frequency of variant type was ≧ 50%. Difference in nucleotide substitution between case and control groups was everywhere, high variant region was mainly at nt 76-nt 147 in PreS2, which contained 9 variants (including A76C, G85A, G87A, C93T, A96C, A99C, T105C, T109A and G110C) with frequency differences of 15.3%-30.40%. Differences in positions between case and control groups were lower than 6.3% for genotype B. The corresponding figure for genotype C was 37.1%-62.9%. When analysis was limited to these variant positions were still marginally statistically significantly associated with HCC subjects with genotype C. Comparing blood samples at baseline and those at follow-up, higher rate (defined as ≧ 20%) for nucleotide change during follow-up was only observed at three positions nt 2898,nt 3174 and nt 529. Conclusions: Genotype B was mostly consistent with adw sequence, while genotype C had much more variations compared with adw sequence. In most of the PreS/S and overlapping P gene region, nucleotide change was infrequent during long-term follow-up period. Compared with controls, cases had more variant types and high variant region was mainly at nt 76-nt 110 in PreS2 region, where lies within 〝a〞 determinant of HBsAg.背景及研究動機………………………………………………… 1
材料與方法……………………………………………………… 4
研究設計………………………………………………………… 4
研究追蹤世代…………………………………………………… 4
病例和對照組…………………………………………………… 5
實驗室分析……………………………………………………… 6
統計方法………………………………………………………… 7
結果……………………………………………………………… 8
病例組和對照組基本資料……………………………………… 8
PreS/S與重疊P區域核苷酸變異分佈……………………………8
PreS/S與重疊P區域核苷酸變異追蹤……………………………9
PreS/S與重疊P區域核苷酸變異和基因型與HCC間危險相關…10
討論………………………………………………………………10
參考文獻…………………………………………………………14
表一 病例組和對照組基線資料特徵………………………………18
表二 在C基因型下，HBV PreS/S及重疊P區域變異與HCC的關係…19
圖一 以HBV adw-pODW282為基準，對照組在HBV PreS1/PreS2基
因區各點變異型頻率分佈……………………………………20
圖二 以HBV adw-pODW282為基準，對照組在HBV S基因區各點變異
型頻率分佈……………………………………………………21
圖三 以HBV adw-pODW282為基準，對照組在HBV S基因區各點變異
型頻率分佈……………………………………………………22
圖四 以對照組為基準，病例和對照組在HBV PreS/S全基因區各點
變異型頻率差異………………………………………………23
圖五 以對照組為基準，病例與對照組在HBV PreS1/S2基因區各點
變異型頻率差異………………………………………………24
圖六 以對照組為基準，病例組與對照組在HBV S基因區各點變異型
頻率差異………………………………………………………25
圖七 以對照組為基準，病例組與對照組在HBV S基因區各點變異型
頻率差異………………………………………………………26
圖八 以參考序列為基準，追蹤期間各變異點上核苷酸型態變化頻
率………………………………………………………………27
圖九 以HBV adw-pODW282為基準，C基因型中各點變異型分佈頻率…
…………………………………………………………………28
圖十 以HBV adw-pODW282為基準，非C基因型中各點變異型分佈頻率
…………………………………………………………………29
附錄 ……………………………………………………………30
實驗方法…………………………………………………………30
附錄表……………………………………………………………36
附錄圖……………………………………………………………3
Investigation of feeding methods for the inverted L/F antennas
No full text碩士近幾年來，行動通訊網路一直是無線通訊最廣泛的應用，伴隨著網路世界的快速發展，網路已成為應用軟體重要的搭載平台，而由固定寬頻網路發展出無線區域網路，乃是非常重要且關鍵的一步，它能使消費者可連接（access）的網路區域延伸涵蓋任何角落。不需網路線只需透過無線行動裝置即可上網，然而，在這些輕巧的行動裝置中，天線要如何整合至電子產品，則需要設計上的巧思，其中縮小天線的面積尺寸為重要的關鍵技術。
本論文首先探究基本的倒L天線結構的特性，比較原先饋入方式之實部阻抗及虛部阻抗等差異性，提出利用偏移饋入的方式，改善ILA於原基頻（1.8GHz）處的阻抗不匹配問題，但依舊保有ILA天線低剖面、體積小等先天上的優點，此一方式和傳統倒F天線（IFA）的概念完全不同。
接著，從接地面上，引進幾種不同幾何形狀的耦合strip，用來增加上述偏移饋入天線的可應用頻率範圍，以達成雙頻天線的設計，並進一步探究此類天線的特性，與原有天線之反射損耗、實部阻抗及虛部阻抗等進行比較，逐步利用耦合strip的變化來達成雙頻模態的設計目標。
最後，本論文探討了改動傳統倒F天線饋入位置的影響。模擬結果顯示，單純的移動倒F天線饋入位置，可以大幅度的移動其中心頻率，且可維持良好的阻抗匹配，這是相當有趣的現象且有其實用價值。In recent years, mobile communication network has been the most widely used wireless application, along with the rapid development of the Internet world wide web. Nowadays, network has become an important platform to carry various software application. Furthermore, the development of wireless LAN out of the fixed broadband networks is a very important and critical step, which enables consumers to access network almost from any place. No need for the cable can one access the network via simply the wireless mobile devices. However, with these compact mobile devices the antenna should be
carefully integrated, which requires design ingenuity. Among which, technologies to reduce the antenna size are important ones .
In this thesis the characteristics of the basic inverted L antenna are examined first. As a good comparison of the original inverted L antenna, an offset-fed inverted L antenna is proposed to improve the ILA, for which the impedance mismatch problem at the fundamental frequency (1.8GHz) is resolved, but still retain the low profile, small size and other inherent advantages of the ILA antenna. The offset-fed approach is is entirely different from the design concept of the traditional inverted F antenna (IFA).
Then, associated with the ground surface, the introduction of several coupling strips of different geometrical shape is employed to increase available frequency range for the offset feed antenna. The goal is to achieve the dual-band antenna design. By exploring the characteristics of such antennas, the return loss, the real part of impedance and imaginary impedance of the original antenna were carefully compared, by which the uses of coupled strip are tested with the aim of dual-band design.
Finally, the paper investigate effect of changing the feeding position of the traditional inverted F antenna. Simulation results show that by simply changing the feeding position the resonant frequency can be substantially moved around, while a very good impedance matching is maintained, which is quite interesting and of practial use.中文摘要．．．．．．．．．．．．．．．．．．．．．．．．．II
英文摘要．．．．．．．． ．．．．．．．．．．．．．．．． IV
第一章 序論．．．．．．．．．．．．．．．．．．．．．． 1
1.1 研究背景．．．．．．．．．．．．．．．．．．． 1
1.2 研究動機．．．．．．．．．．．．．．．．．．．．2
1.3 論文架構．．．．．．．．．．．．．．．．．．．．4
第二章 偏移饋入ILA天線的設計(一)．．．．．．．．．．． 5
2.1 倒L天線(Inverted L Antenna,簡稱ILA)的原理．． 5
2.1.1倒L型天線與單極天線的特性比較．．．．．．．．．．6
2.1.2偏移饋入位置的倒L型天線．．．．．．．．．．．．．9
2.2 ILA饋入點水平移動(改變L1)的探討．．．．．．．． 12
2.3 增加寄生元件Strip1以期雙頻應用．．．．．．．．．18
2.4 引進寄生strip2 (高度H3)使其雙頻應用．．．．．． 21
2.5 增加寄生元件L4使其雙頻應用．．．．．．．．．．．26
2.6 引進寄生strip4使其雙頻應用．．．．．．．．．．．29
第三章 偏移饋入ILA倒L天線應用的設計(二) ．．．．．．． 33
3.1 偏移饋入ILA天線(2.4G)簡介．．．．．．．．．．． 33
3.2 倒L天線水平部份L總長之比較．．．．．．．．．． 37
3.3 引進一倒L形的寄生strip使成雙頻．．．．．．．． 41
3.4 引進一形狀q的寄生strip使成雙頻．．．．．．．． 46
3.5 引進矩形的寄生strip使成雙頻．．．．．．．．．． 49
3.6 天線輻射場型模擬與實測．．．．．．．．．．．． 54
第四章 移動饋入位置的探討．．．．．．．．．．． ．．． 59
4.1 倒F天線饋入位置的移動測試．．．．．．．． ．．．59
4.2 倒F天線的饋入點向下移動．．．．．．．．． ．．．66
4.2.1倒F天線的饋入點向下移動．．．．．．．．．．． ．．． 66
4.2.2 降低高度H並向下移動倒F天線饋入位置．．．．．．．． 74
第五章 結論．．．．．．．．．．．．．．．．．．．．．．82
參考文獻．．．．．．．．．．．．．．．．．．．．．．．． 84
圖目錄
圖 2.1倒L型天線的示意圖．．．．．．．．．．．．．．．．．．5
圖 2.2單極天線被彎曲(Bend)成倒L型天線的示圖．．．．．．．．7
圖 2.3不同高度H與彎曲長度L1的倒L型天線之反射損耗模擬圖．． 7
圖 2.4不同高度H與彎曲長度L1的倒L型天線的輸入阻抗圖．．．． 8
圖 2.5 (a)傳統饋入的倒L天線之結構圖，(b)偏移饋入的倒L天線之 結構圖．．．．．．．．．．．．．．．．．．．．．．． 10
圖 2.6 傳統ILA與偏移饋入的ILA之反射損耗模擬圖．．．．．． 11
圖 2.7偏移饋入的ILA之實測與模擬反射損耗圖的比較．．．．． 11
圖 2.8傳統ILA與偏移饋入的ILA之輸入阻抗圖．．．．．．．．．12
圖 2.9 改變饋入點位置的偏移饋入ILA天線圖結構示意圖．． 14
圖 2.10移動饋入點位置L1(4mm至9mm)的偏移饋入ILA之反射損耗
模擬圖．．．．．．．．．．．．．．．．．．．．．．．．．．15
圖 2.11移動饋入點位置L1(8mm至11mm)的偏移饋入ILA之反射損耗
模擬圖．．．．．．．．．．．．．．．．．．．．．．．．．．15
圖 2.12針對偏移饋入ILA，L1分別為4mm和9mm的模擬與實測反
射損耗圖的比較．．．．．．．．．．．．．．．．．．．．．．16
圖 2.13移動饋入點位置L1(4和9)的偏移饋入ILA輸入阻抗圖．．．17
圖 2.14偏移饋入ILA伴隨寄生strip1（高度H2）的天線結構示意
圖．．．．．．．．．．．．．．．．．．．．．．．．．． ． 19
圖 2.15改變高度H2對偏移饋入ILA伴隨寄生strip1的天線之反射損耗
模擬圖比較．．．．．．．．．．．．．．．．．．． ．．．． 20
圖 2.16改變距離d1對偏移饋入ILA伴隨寄生strip1的天線之反射損耗模擬圖比較．．．．．．．．．．．．．．．．．．．．．． ．20
圖 2.17針對偏移饋入ILA伴隨寄生strip1的天線，令d1=1mm且
H2=5mm的實測與模擬之反射損耗圖比較．．．．．．．．．．．．21
圖 2.18引進寄生strip2的偏移饋入ILA天線結構示意圖．．．．．23
圖 2.19引進寄生strip2的偏移饋入ILA天線，改變間距d3對應的反射
損耗模擬圖比較（固定H3=5mm）．．．．．．．．．．．．．．．24
圖 2.20引進寄生strip2的偏移饋入ILA天線，改變高度H3對應的反射
損耗模擬圖比較（固定間距d3=0.5mm）．．．．．．．．．．．．24
圖 2.21針對引進寄生strip2的偏移饋入ILA天線，其實際量測與模擬之反射損耗模擬圖．．．．．．．．．．．．．．．．．．．． 25
圖 2.22針對引進寄生strip2的偏移饋入ILA天線，當高度H3不同時對
應的之輸入阻抗圖．．．．．．．．．．．．．．．．．．．．．25
圖 2.23引進寄生strip3（長度L4）的偏移饋入ILA天線結構示意
圖．．．．．．．．．．．．．．．．．．．．．．．．．．．．27
圖 2.24針對引進寄生strip3的偏移饋入ILA，改變長度L4對應的反射
損耗模擬圖．．．．．．．．．．．．．．．．．．．．．．．．28
圖 2.25針對引進寄生strip3的偏移饋入ILA，改變長度L4對應的輸入阻抗圖．．．．．．．．． ．．．．．．．．．．．．．．．． 28
圖 2.26引進寄生strip4(寬L5、高H2)的偏移饋入ILA天線結構示意
圖．．．．．．．．．．．．． ．．．．．．．．．．．．．． 30
圖 2.27針對引進寄生strip4(固定寬L5=2、d2=3) 的偏移饋入ILA，
改變長度H2對應的反射損耗模擬圖．．．．．．．．．．．．．．31
圖 2.28引進寄生元件strip4，改變長度d2之反射損耗模擬圖．． 31
圖 2.29 d2=2mm及H2=0.5mm之模擬與實測反射損耗模擬圖．．． 32
圖 2.30引進寄生strip4，改變長度d2所對應輸入阻抗圖．．．． 32
圖 3.1將尺寸縮小後的偏移饋入ILA(2.4G)天線的兩者結構圖示意圖．．．．．．．．．．．．．．．．．．．．．．．．．．．．34
圖 3.2偏移饋入ILA(2.4G)天線之反射損耗模擬圖．．．．．．． 35
圖 3.3偏移饋入ILA(2.4G)天線（圖3.1(b)）的實測與模擬反射損耗
圖．．．．．．．．．．．．．．．．．．． ．．．．．．．． 35
圖 3.4偏移饋入ILA(2.4G)天線（圖3.1）之輸入阻抗圖．．．．．36
圖 3.5針對偏移饋入ILA(2.4G)天線（圖3.1(b)），改變饋入位置L1對應的之反射損耗模擬比較圖．．．．．．．．．．．．．．．．37
圖 3.6改變L2總長之倒L天線圖示意圖．．．．．．．．．．．． 39
圖 3.7改變總長度L之反射損耗模擬圖．．．．．．．．．．．． 40
圖 3.8針對偏移饋入ILA，當其長度L為15mm及20mm的實測與模擬
反射損耗圖．．．．．．．．．．．．．．．．．．．．．．． 40
圖 3.9針對偏移饋入ILA，當其長度L分別為15、30mm之輸入阻圖 41
圖 3.10引進一倒L形的寄生strip（高度H2與寬度G2）的偏移饋入
ILA天線的結構示意圖．．．．．．．．．．．．．．．．．．． 42
圖 3.11為引進寄生strip並改變其間距d2所對應的反射損耗之比較 （固定H2=5mm和G2=2.5mm），w/o strip為原偏移饋入ILA．．．．43
圖 3.12改變間距d2所對應的反射損耗模擬圖比較．．．．．．． 44
圖 3.13為當d2=3mm、H2=5mm且G2=2.5mm時，此偏移饋入ILA天線
的實測反射損耗與模擬圖比較．．．．．．．．．．．．．．．．44
圖 3.14引進寄生strip 前後輸入阻抗的差異比較圖．．．．．． 45
圖 3.15間距d2分別為1mm和3mm的輸入阻抗圖．．．．．．．． 46
圖 3.16具形狀q的寄生strip（改變高度H3）之偏移饋入ILA天線
結構的示圖．．．．．．．．．．．．．．．．．．．． 47
圖 3.17針對一具形狀q的寄生strip之偏移饋入ILA天線，改變高度H3
所對應的反射損耗模擬圖．．．．．．．．．．．．．． 48
圖 3.18針對一具形狀q的寄生strip之偏移饋入ILA天線，H2分別為 1mm與4mm（固定G2=3mm）的輸入阻抗圖．．．．．．．．．．．．48
圖 3.19具矩形寄生strip（改變d3）之偏移饋入ILA天線的結構示意
圖．．．．．．．．．．．．．．．．．．．．．．．．．．．．50
圖 3.20針對具矩形寄生strip之偏移饋入ILA天線，改變間d3(3mm-4mm) 所對應的反射損耗模擬圖．．．．．．．．．．．．．．． 51
圖 3.21針對具矩形寄生strip之偏移饋入ILA天線，改變間距
d3(4.5mm-5.5mm) 所對應的反射損耗模圖．．．．．．． 52
圖 3.22針對具矩形寄生strip之偏移饋入ILA天線，改變間距
d3(5.1mm-5.3mm) 所對應的反射損耗模擬圖．．．．．． 52
圖 3.23針對具矩形寄生strip之偏移饋入ILA天線，當d3分別為3mm
與5.2mm之反射損耗圖．．．．．．．．．．．．．．．．53
圖 3.24(a) d3=3mm，(b) d3=5.2mm實體雙頻天線圖．．．．．． 54
圖 3.25 d3=3mm和d3=5.2mm模擬與實測反射損耗圖．．．．．．．54
圖 3.26 d3=3mm，H-plane(X-Z平面)模擬與實測之輻射場型圖(@2.45GHz)．．．．．．．．．．．．．．．．．．．．．．．．55
圖 3.27 d3=3mm，H-plane(X-Z平面)模擬與實測之輻射場型圖(@5.85GHz)．．．．．．．．．．．．．．．．．．．．．．．．55
圖 3.28 d3=3mm，E-plane(Y-Z平面)模擬與實測之輻射場型圖(@2.45GHz)．．．．．．．．．．．．．．．．．．．．．．．．56
圖 3.29 d3=3mm，E-plane(Y-Z平面)模擬與實測之輻射場型圖(@5.85GHz)．．．．．．．．．．．．．．．．．．．．．．．．56
圖 3.30 d3=5.2mm，H-plane(X-Z平面)模擬與實測之輻射場型圖(@2.45GHz) ．．．．．．．． ．．．．．．．．．．．．．．．57
圖 3.31 d3=5.2mm，H-plane(X-Z平面)模擬與實測之輻射場型圖(@5.15GHz) ．． ．．．．．．．．．．．．．．．．．．．．．57
圖 3.32 d3=5.2mm，E-plane(Y-Z平面)模擬與實測之輻射場型圖(@2.45GHz) ． ．．．．．．．．．．．．．．．．．．．．．．58
圖 3.33 d3=5.2mm，E-plane(Y-Z平面)模擬與實測之輻射場型圖(@5.15GHz) ．．．．．．．．．．．．．．．．．．．．．．．58
圖 4.1使ILA結構轉換成傳統的IFA天線結構的示意圖（改變饋入位置
L1）．．．．．．．．．．．．．．．．．．．．．．．．60
圖 4.2針對IFA天線，改變L1(10~22mm) 所對應的反射損耗模擬圖．．．．．．．．．．．．．．．．．．．．．．．．．．．．61
圖 4.3針對IFA天線，改變L1(2mm~10mm)所對應的反射損耗模擬
圖．．．．．．．．．．．．．．．．．．．．．．．．．．．．62
圖 4.4針對IFA天線，改變長度L1(6mm~10mm) 所對應的反射損
耗模擬圖．．．．．．．．．．．．．．．．．．．．．．63
圖 4.5針對IFA天線，改變長度L1(1mm~5mm) 所對應的反射損耗模
擬圖．．．．．．．．．．．．．．．．．．．．．．．．64
圖 4.6針對IFA天線，改變長度L1=2mm，在4.55GHz(Phase=0°)時所
對應的電流向量圖．．．．．．．．．．．．．．．．．．65
圖 4.7針對IFA天線，改變長度L1=10mm，在4.0GHz(Phase=90°) 所
對應的電流向量圖．．．．．．．．．．．．．．．．．．65
圖 4.8針對IFA天線，改變長度L1=20mm，在2.29GHz(Phase=0°) 所
對應的電流向量圖．．．．．．．．．．．．．．．．．．66
圖 4.9饋入點向下移動的IFA天線（改變L1）結構之示意圖．．． 68
圖 4.10針對饋入點向下移動的IFA天線，改變L1(10mm~22mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 69
圖 4.11針對饋入點向下移動的IFA天線，改變L1(2mm~10mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 70
圖 4.12針對饋入點向下移動的IFA天線，改變L1(6mm~10mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 71
圖 4.13針對饋入點向下移動的IFA天線，改變L1(1mm~6mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 71
圖 4.14針對IFA天線，改變長度L1=2mm，在4.57GHz(Phase=0°) 所
對應的電流向量圖．．．．．．．．．．．．．．．．． 72
圖 4.15針對IFA天線，改變長度L1=10mm，在3.99GHz(Phase=90°)
所對應的電流向量圖．．．．．．．．．．．．．．．． 72
圖 4.16針對IFA天線，改變長度L1=20mm，在2.29GHz(Phase=0°)
所對應的電流向量圖．．．．．．．．．．．．．．．． 73
圖 4.17降低高度H後的IFA天線（改變L1）天線之結構示意圖．． 75
圖 4.18針對降低高度H後的IFA天線，改變L1(10mm~22mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 76
圖 4.19針對降低高度H後的IFA天線，改變L1(10mm~2mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 77
圖 4.20針對降低高度H後的IFA天線，改變L1(10mm~6mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 78
圖 4.21針對降低高度H後的IFA天線，改變L1(6mm~1mm)所
對應的反射損耗模擬圖．．．．．．．．．．．．．．． 79
圖 4.22針對IFA天線，改變長度L1=2mm，在4.4GHz(Phase=0°) 所
對應的電流向量圖．．．．．．．．．．．．．．．．． 80
圖 4.23針對IFA天線，改變長度L1=11mm，在4.36GHz(Phase=90°)
所對應的電流向量圖．．．．．．．．．．．．．．．． 80
圖 4.24針對IFA天線，改變長度L1=20mm，在2.38GHz(Phase=0°) 所
對應的電流向量圖．．．．．．．．．．．．．．．．． 81
表目錄
表 2.1 虛部為零，實部與共振頻率隨高度H改變時之對照表．．．9
表 2.2 改變餽入點位置的偏移饋入ILA天線各參數長度．．．． 14
表 2.3 偏移饋入ILA伴隨寄生strip1的天線結構各參數長度．． 19
表 2.4 引進寄生strip2的偏移饋入ILA天線之各參數長度（改變
H3）．．．．．． ．．．．．．．．．．．．．．．． 23
表 2.5 引進寄生strip3的偏移饋入ILA天線各參數長度．．．． 28
表 2.6 引進寄生strip4的偏移饋入ILA天線各參數長度．．．． 30
表 3.1 將尺寸縮小後的偏移饋入ILA(2.4G)天線各參數長度．． 34
表 3.2 倒L天線各參數長度．．．．．．．．．．．．．．．． 39
表 3.3 引進一倒L形的寄生strip（高度H2與寬度G2）的偏移饋入
ILA天線各參數對應數據．．．．．．．．．．．．．． 43
表 3.4 具形狀q的寄生strip（改變高度H3）之偏移饋入ILA天線
之各參數長度． ．．．．．．．．．．．．．．．．． 47
表 3.5 具矩形寄生strip（改變d3）之偏移饋入ILA天線各參數長
度．．．．．．．．．．．． ．．．．．．．．．．． 52
表 4.1 使ILA結構轉換成傳統的IFA天線（改變L1）之各項長度參
數．．．．．．．．．．．．．．．．．．．．．．．．61
表 4.2 針對IFA天線，改變長度L1（10~22mm）所對應頻寬．．．62
表 4.3 針對IFA天線，改變長度L1（1~10mm）所對應頻寬．．． 63
表 4.4 饋入點向下移動的IFA天線（改變L1）的各項長度參數． 68
表 4.5 針對饋入點向下移動的IFA天線，改變長度L1（10~22mm）所
對應的頻寬．．．．．．．．．．．．．．．．．．．．69
表 4.6 針對饋入點向下移動的IFA天線，改變長度L1(1mm~10mm)
所對應的頻寬．．．．．．．．．．．．．．．．．．．70
表 4.7 降低高度H後的IFA天線（改變L1）之各項參數．．．．．76
表 4.8 改變長度L1 (10~22mm)所對應的頻寬．．．．． ．． 77
表 4.9 改變長度 L1 (1~10mm)所對應的頻寬．．．．．．．．．78學號: 697440369, 學年度: 9
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