資源描述:
《介質(zhì)球透鏡多波束天線研究》由會員上傳分享,免費在線閱讀,更多相關(guān)內(nèi)容在學(xué)術(shù)論文-天天文庫。
1、碩士論文介質(zhì)球透鏡多波柬天線研究摘要現(xiàn)今的三坐標雷達廣泛采用堆積多波束體制,而多波束天線是實現(xiàn)堆積多波束的關(guān)鍵部件。本文對一種可以產(chǎn)生寬掃描角度的多波束天線進行了研究,它由平面饋源天線和一個單介質(zhì)球透鏡組成。多個饋源天線圍繞著球透鏡對稱排列,通過它們之間的切換來實現(xiàn)波束的掃描。具體研究工作如下:1)討論了透鏡天線的基本原理和分析方法。用射線追蹤法建立了分析透鏡系統(tǒng)的通用模型,并對系統(tǒng)效率進行了定義.2)針對TSA平面天線體積大的缺點,設(shè)計了一個八木饋源天線,并用HFSS進行了仿真,總長度只有1.4五,而相同條件下TSA天線需要5z。3)重點研究了多個參數(shù)對天線的
2、影響,特別是對系統(tǒng)效率和遠場輻射特性的影響.(a)透鏡介質(zhì)的折射率影響系統(tǒng)的調(diào)焦(b)天線的主瓣寬度跟透鏡半徑里反比關(guān)系(c)饋源天線與透鏡的距離主要影響天線的效率和副瓣電平(d)隨著饋源天線主瓣寬度的增加,溢出效率會增高,但系統(tǒng)的遠場方向圖會變窄(e)還分析了切割部分球面對天線效率的影響。4)根據(jù)上述結(jié)果設(shè)計了一個工作于14GI'IZ的單介質(zhì)球透鏡多波束天線,相鄰波束交點電平--3dB,20個波束可以實現(xiàn)3600的波束掃描,系統(tǒng)的效率可以達到50%.關(guān)鍵詞:介質(zhì)透鏡,幾何光學(xué),射線追蹤法,八木天線碩士論文介質(zhì)球透鏡多波束天線研究AbstractMultiple
3、-beamalltenllaplaysakeyroleinthree·dimensionalradar,Inthisthesis.onekindofdielectriclensalatcl,alasystemwhich啪leadtogreatlyincreasedsP..,ancoveragehasbeeninvestigated.Thesystemiscomposedoffeedan“mnasanddielectricsphericallens,Thefeed鋤1tam∞aleplacedaroundthesphere;thebeam$c1111啪beachi
4、evedbytheswitchingofthefeed.Themainresearchis:i)Thebasicprincipleand鋤alytiealmethodofthelensantennaatedisemsed.Ageneralmodelofthedielectriclensaltltellnaisbuiltandallkindsofefficiencyhavebeendeftned.ii)11地volumeofthetaredslotallt朗113aisverybig.SOyagilult∞naisdesignedbyHFSS.Thewholele
5、ngthoftlaisantennaisonly1.4五。whilethetapedslotantcrlnawillneed5Ainthesal'llceonditi蛆.iii)Afewparameterswhich鋤inferencetheperform缸eeofthesystemhavebeeninvestedespeciallytotheefficiencyandfar-fieldradiationproperties.(a)n圮indexofrefractionofthelensmainlyinfluencethefocusingpropertiesCo
6、)Thebiggertheradiusofthesphere,theilarl-owcrbeamwidthofthearltCl'ma.(c)Thedistancebetweenthesphereandthefeedantennamainlyinfluencetheefficiencyofthesystemandthesidelobe(d)Alongwiththeincreaseofthefeedantenna’sbeamwidth,spilloverefficiencywillincrease,butthebeamwidthofthesystemwilldec
7、rease.(e)Otherwisetheresearchworkalsoinvestshowcuttingthespheresinfluencetheefficiencyofthesystem.iv)11"workdiscussedabovehasbeenutilizedtodesignamultiplebeamhomogenousdielcelriesphericallensBlll.e/'masystemat140Hz,thebeamsoverlapat3dBlevel,andscancoveragecanreach3600bythe20bealmsand
8、theefficienc