【摘要】：相控陣天線由于具有快速掃描的特點(diǎn),使其在雷達(dá)探測(cè)以及衛(wèi)星通信等領(lǐng)域具有不可替代的作用。針對(duì)平面相控陣天線,為了使其波束掃描范圍更大,應(yīng)用范圍更廣,近年來研究學(xué)者們把重點(diǎn)放在了對(duì)相控陣天線掃描角度的擴(kuò)展和波束質(zhì)量的優(yōu)化上。本學(xué)位論文是以平面微帶相控陣天線為研究載體,對(duì)相控陣天線的大角度掃描及低旁瓣優(yōu)化問題進(jìn)行研究和探討,主要內(nèi)容如下:第一部分主要對(duì)不同形式的寬波束相控陣單元天線的工作特點(diǎn)和原理進(jìn)行研究和分析。首先,在平面微帶天線結(jié)構(gòu)中,運(yùn)用縫隙等結(jié)構(gòu)產(chǎn)生等效磁流。分析磁流和電流在無限大金屬地板環(huán)境下的不同輻射狀態(tài)。根據(jù)金屬表面的邊界條件和鏡像原理分析得出平面磁流對(duì)于微帶天線寬波束和低仰角輻射的產(chǎn)生具有重要作用,并據(jù)此設(shè)計(jì)具有寬波束或低仰角輻射特性的微帶平面天線。其次,分析了基片集成波導(dǎo)結(jié)構(gòu)的縫隙天線。通過理論及仿真介紹基片集成波導(dǎo)上縫隙的排布方式以及工作原理,分析縫隙對(duì)天線輻射的影響,最終獲得寬波束輻射特性。最后,在微帶天線上將磁流和電流相結(jié)合,得到一種產(chǎn)生寬波束圓極化輻射方向圖的電磁偶極子天線。分析了電流和磁流同時(shí)產(chǎn)生的方法,以及二者之間幅度和相位的調(diào)節(jié),水平極化電場(chǎng)和垂直極化電場(chǎng)在保持幅度相同的情況下實(shí)現(xiàn)90°相位差地結(jié)合,形成圓極化輻射波束。將這三種基本的原理引入到微帶天線中,設(shè)計(jì)了四種不同形式的寬波束或低仰角高增益波束覆蓋的單元天線,為后面的相控陣天線大角度掃描研究打下了基礎(chǔ)。第二部分主要對(duì)平面微帶相控陣天線的大角度掃描問題進(jìn)行了研究,對(duì)不同天線單元以及不同相控陣結(jié)構(gòu)的特點(diǎn)進(jìn)行了分析和總結(jié)。首先,介紹了以微帶磁偶極子單元天線和微帶磁偶極子八木子陣所構(gòu)建的兩種相控陣天線的陣列排布方式及工作原理。陣列中重點(diǎn)研究了耦合貼片結(jié)構(gòu)在陣列有源單元間耦合能量傳遞方面所起到的作用。在耦合作用的幫助下陣列的有源單元方向圖相比自由環(huán)境中得到了擴(kuò)展,使得陣列的掃描角度大幅度提高。其次,以基片集成波導(dǎo)縫隙天線為單元構(gòu)建相控陣天線。陣列中金屬通孔所構(gòu)成的等效電壁保證了單元天線電場(chǎng)模式穩(wěn)定,有源單元保持17%以上的相對(duì)帶寬。相控陣在工作頻帶內(nèi)保持大角度的掃描范圍。然后,以電磁偶極子天線為單元構(gòu)建相控陣天線,分析陣列結(jié)構(gòu)對(duì)有源單元輻射方向圖的極化和波束寬度等參數(shù)的影響,實(shí)現(xiàn)了大角度的圓極化掃描。最后,在平面微帶正方形貼片天線上同時(shí)激勵(lì)TM010模式和零階諧振(ZOR)模式,利用二者在方向圖上互補(bǔ)的特點(diǎn)形成寬波束覆蓋的輻射方向圖,由其構(gòu)建的6×6的平面相控陣天線實(shí)現(xiàn)了二維空間上的雙極化大角度掃描。第三部分主要以微帶磁偶極子相控陣為載體,研究大角度范圍內(nèi)的掃描波束低旁瓣優(yōu)化問題。首先,采用遺傳算法對(duì)陣因子進(jìn)行優(yōu)化,利用CST計(jì)算得出的有源單元方向圖作為陣因子中的單元,從而計(jì)及耦合所帶來的影響。實(shí)驗(yàn)表明該方法可以有效降低大角度掃描范圍內(nèi)掃描波束的旁瓣大小。然后,運(yùn)用神經(jīng)網(wǎng)絡(luò)預(yù)測(cè)的方法代替陣因子對(duì)相控陣的掃描波束進(jìn)行模擬計(jì)算。通過反饋式神經(jīng)網(wǎng)絡(luò)對(duì)陣列進(jìn)行模擬,其計(jì)算結(jié)果避免了耦合匹配等不確定因素的干擾,更加準(zhǔn)確。對(duì)預(yù)測(cè)結(jié)果運(yùn)用遺傳算法進(jìn)行優(yōu)化。最后,對(duì)優(yōu)化結(jié)果進(jìn)行試驗(yàn)驗(yàn)證,仿真和測(cè)試都證實(shí)了該方法在大角度范圍內(nèi)實(shí)現(xiàn)了對(duì)旁瓣的優(yōu)化。
[Abstract]:The phased array antenna has an irreplaceable role in the fields of radar detection and satellite communication due to the characteristics of fast scanning. In order to make the beam scanning range of the phased array antenna larger and the application range is wider, the research scholars have focused on the spread of the scanning angle of the phased-array antenna and the optimization of the beam quality in recent years. In this thesis, a planar microstrip phased array antenna is used as the research carrier, and the large-angle scanning and the low sidelobe optimization problem of the phased-array antenna are studied and discussed. The main contents are as follows: The first part mainly studies and analyzes the working characteristics and the principle of the wide-beam phased-array unit antenna in different forms. First, in a planar microstrip antenna structure, an equivalent magnetic flux is generated by using a structure such as a slot. The different radiation conditions of the magnetic flux and the current in an infinite metal floor environment are analyzed. According to the boundary condition and the mirror image principle of the metal surface, it is concluded that the plane magnetic flux plays an important role in the generation of the wide-beam and low-elevation radiation of the microstrip antenna, and the microstrip-plane antenna with a wide beam or low-elevation radiation characteristic is designed accordingly. Secondly, the slot antenna of the integrated waveguide structure of the substrate is analyzed. Through the theory and simulation, the arrangement mode and working principle of the slot on the integrated waveguide of the substrate are introduced, and the influence of the gap on the antenna radiation is analyzed, and the radiation characteristics of the wide beam are finally obtained. And finally, combining the magnetic current and the current on the microstrip antenna to obtain an electric magnetic dipole antenna which generates a wide beam circular polarization radiation pattern. The method for simultaneously generating the current and the magnetic current is analyzed, the amplitude and the phase of the current and the magnetic current are adjusted, the horizontal polarization electric field and the vertical polarized electric field are combined with a 90 degree phase difference under the condition that the amplitude is the same, and the circularly polarized radiation beam is formed. The three basic principles are introduced into the microstrip antenna, four different forms of wide-beam or low-elevation high-gain beam-covered cell antenna are designed, which lays a foundation for the large-angle scanning of the later phased-array antenna. The second part mainly studies the large-angle scanning of planar micro-strip phased array antenna, and analyses and summarizes the characteristics of different antenna elements and different phased array structures. First, the array arrangement and working principle of two phased array antennas based on the microstrip magnetic dipole element antenna and the microstrip magnetic dipole eight-wood sub-array are introduced. In that array, the role of the coupled patch structure in the energy transfer between the active elements of the array is studied. The active element direction diagram of the array is expanded in a free environment compared with the aid of the coupling action, so that the scanning angle of the array is greatly improved. And secondly, a phased array antenna is constructed by using a substrate integrated waveguide slot antenna as a unit. The equivalent electric wall of the metal through-hole in the array ensures that the electric field mode of the unit antenna is stable, and the active unit maintains relative bandwidth of more than 17%. The phased array maintains a wide angle of scanning range in the operating band. The effects of the array structure on the parameters such as the polarization and the beam width of the active unit's radiation pattern are analyzed, and the large-angle circular polarization scanning is realized. finally, the TM010 mode and the zero-order resonance (ZOR) mode are simultaneously excited on the planar micro-strip square patch antenna, The dual-polarization and large-angle scanning in the two-dimensional space is realized by the planar phased-array antenna of the 6-axis 6 constructed by the planar phased-array antenna. The third part mainly uses the micro-strip magnetic dipole phased array as the carrier to study the low sidelobe optimization problem of the scanning beam in the wide range of angles. First, a genetic algorithm is used to optimize the array factor, and the active cell orientation map calculated by the CST is used as a unit in the array factor, thus taking into account the influence caused by the coupling. The experiment shows that the method can effectively reduce the sidelobe size of the scanning beam in the wide-angle scanning range. Then, the method of neural network prediction is used instead of the array factor to calculate the scanning beam of the phased array. The array is simulated by a feedback type neural network, and the calculation result avoids the interference of the uncertain factors such as the coupling matching and the like, and is more accurate. The genetic algorithm is used to optimize the prediction results. Finally, the experimental verification, simulation and testing of the optimization results confirm that the method achieves the optimization of the sidelobe in a wide range of angles.
【學(xué)位授予單位】：電子科技大學(xué)
【學(xué)位級(jí)別】：博士
【學(xué)位授予年份】：2017
【分類號(hào)】：TN821.8

【參考文獻(xiàn)】

相關(guān)博士學(xué)位論文 前1條

1 丁霄;基于方向圖可重構(gòu)技術(shù)的相控陣大角度掃描特性研究[D];電子科技大學(xué);2013年

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本文編號(hào)：2487238