【正文】 er, we should not ignore the fact that slot antenna has many advantages. To overe this contradiction, the paper provides a design of slottedwaveguide antenna which is excited from both end of the waveguide, and simulates it with the help of HFSS. According to the requirement of directivity, this researcher designs the amplitude distribution of the apertures based on modified Chebyshev array, and calculates it by writing program using MATLAB. The plex arrangement of the slots in the narrow face of a waveguide brings much trouble to model it in HFSS, so the present paper offers a method to create the model by producing model scripts in MATLAB. This method can establish a plex model quickly and exactly. The simulating result shows that this antenna can basically satisfy the practical requirement. Key Words： slot antenna； FDTD； both end excited； Chebyshev array 目 錄 目 錄 第 1 章 緒論 .............................................................................................................................. 1 ...................................................................................... 1 .................................................................................. 1 脈沖寬度與天線長度 ......................................................................................... 1 天線效率 ............................................................................................................. 2 .................................................................................................. 2 .......................................................................................................... 3 第 2 章 縫隙天線的基本原理 .................................................................................................. 4 ...................................................................................................................... 4 電偶極子與磁偶極子的對(duì)偶性 ......................................................................... 4 電流元和磁流元的對(duì)偶性 ................................................................................. 4 對(duì)偶原理的建立 ................................................................................................. 5 .......................................................................................... 6 .................................................................................................. 8 開縫形式 ............................................................................................................. 8 波導(dǎo)縫隙的阻抗特性 ......................................................................................... 9 ........................................................................................................ 11 第 3 章 時(shí)域有限差分法的基本應(yīng)用 .................................................................................... 14 ............................................................................................................................ 14 FDTD 基本技術(shù) .............................................................................. 15 自由空間一維電磁波傳播的 FDTD 模擬 ...................................................... 15 一維電磁波在無耗介質(zhì)中傳播的 FDTD 模擬 ............................................... 18 一維平面波在導(dǎo)電損耗介質(zhì)中傳播的 FDTD 模擬 ....................................... 20 色散媒質(zhì)的處理方法 ....................................................................................... 22 FDTD 基本技術(shù) .............................................................................. 24 二維 FDTD 基本計(jì)算公式 ............................................................................... 24 二維各向異性 PML 吸收層 ............................................................................. 27 第 4 章 應(yīng)用 FDTD 計(jì)算縫隙天線遠(yuǎn)場 ................................................................................ 34 FDTD 計(jì)算公式 .................................................................................................. 34 Yee 元胞 ............................................................................................................ 34 自由空間中三維 FDTD 公式 ........................................................................... 35 FDTD 計(jì)算縫隙天線遠(yuǎn)場波形 .......................................................................... 37 第 5 章 雙端相向饋電波導(dǎo)縫隙天線設(shè)計(jì) ............................................................................ 44 ............................................................................................................................ 44 ............................................................................................................ 45 切比雪夫分布律 ............................................................................................... 45 各縫隙電導(dǎo)和傾角的計(jì)算 ............................................................................... 50 縫隙間距 d 和縫隙個(gè)數(shù) n 的確定 ................................................................... 53 ........................................................................................................ 54 結(jié) 束 語 .................................................................................................................................. 56 參 考 文 獻(xiàn) ............................................................................................................................ 57 致 謝 .................................................................................................................................. 61 基于時(shí) 域有限差分法的縫隙天線的分析與設(shè)計(jì) 1 第 1 章 緒論 縫隙天線的研究狀況及發(fā)展 對(duì)縫隙天線的 研究始于二十世紀(jì)四十年代。但裂縫天線有許多優(yōu)點(diǎn)，為了克服上述矛盾， 論文的最后設(shè)計(jì)了一種雙端相向饋電的波導(dǎo)裂縫天線 ， 并借助 Ansoft公司的高頻電磁仿真軟件 HFSS 進(jìn)行仿真。 本學(xué)位論文屬于： 保密 □ 不保密□（請(qǐng)?jiān)谝陨戏娇騼?nèi)打“√” ） 論文作者簽名： 導(dǎo)師簽名： 日期： 年 月 日 中 文 摘 要 摘 要 時(shí)域有限差分法（ FDTD）作為一種電磁場數(shù)值計(jì)算方法以其簡單、直觀等特點(diǎn)近年來備受業(yè)界關(guān)注和厚愛。 本聲明的法律責(zé)任由本人承擔(dān)。除論文中已經(jīng)注明引用的內(nèi)容外， 對(duì)論文的研究做出重要貢獻(xiàn)的個(gè)人和集體，均已在文中以明確方式標(biāo)明 .本論文中不包含任何未加明確注明的其他個(gè)人或集體已經(jīng)公開發(fā)表或未公開發(fā)