資源描述:
《單極天線設(shè)計和地研究》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、中文摘要駐波系數(shù)小、全向性能好、且尺寸小、結(jié)構(gòu)簡單、重量輕、成本低的天線在現(xiàn)代通信系統(tǒng)中很受歡迎。單極天線不僅具有上述特點,同時具有頻帶寬、剖面輪廓低、易與微帶饋電網(wǎng)絡(luò)連接等優(yōu)點,滿足現(xiàn)代通信中移動終端對天線小尺寸、寬頻帶的要求,因而收到廣泛關(guān)注。本文為進一步擴展天線帶寬,增加超寬帶天線的阻帶,在分析現(xiàn)有單極天線特性的基礎(chǔ)上,進行了大量的工作,研究出兩種新型單極天線,并進行了實際制作和測試,測試結(jié)果與理論結(jié)果吻合較好。本文所做的創(chuàng)新性工作有:1.提出了一種輻射體中心開孔的圓片形單極天線,該天線明顯地改善了圓形單極天線的諧振性能,比不開孔的圓形天線具有更寬的帶寬;研究
2、了該天線的阻帶特性,通過在輻射體上增加圓弧形槽使天線具有阻帶特性,對WLAN頻段的信號進行有效的過濾,避免相互干擾。2.提出了一種新型階梯式單極子天線,該天線通過采用層級式饋電結(jié)構(gòu),使天線饋源處電流連續(xù)分布,從而改善了天線的匹配情況。對以上兩種天線均做了數(shù)值仿真,并實際制作和測試了第一種天線,理論上的寬頻帶特性得到了實驗的驗證。實驗結(jié)果表明,這兩種天線都能用于超寬帶通信系統(tǒng)。關(guān)鍵詞:單極天線,開槽技術(shù)、超寬帶天線、寬頻帶天線、微帶饋電、小型化AntennaswithsmallVSWR,ommi—directionalradiation,smallsize,simpl
3、estructure,lightweightandlowcost,areveryattractivefornowadayscommunicationapplications.Theplanarmonopoleantennanotonlyhasthesemeritsbutalsohasthepropertiesofwideband,lowprofile,andeasilyconnectingtomicrosrtiplinefeedingnetwork.Therefore,planarmonopoleantennassatisfythesmallsizeandbroad
4、bandrequirementoftoday'scommunicationterminal.So,planarmonopoleantennasattractmoreandmoreattentions.Inordertowidenthebandofantennasandgetbandstop,thisthesisconductsmanyworksbasedontheanalysisoftheexistingreferencesaboutmonopoleantennas.Twonewkindsofmonopoleantennasareproposed,fabricate
5、dandmeasured.Themeasuredresultsareinwellagreementwithsimulatedresults.Thecreativeworksofthisthesisale:1.Anewkindofcicularmonopoleantennawithaneyeletinthecenteroftheradiationisproposed.Theresonanceperfomtmaceisimprovedbytheeyeletandthefiequencebandofthismonopoleantennaiswiderthanthatwit
6、houteyelet.Band-notchedcharacteristicsarerealizedbyinsertingslotsonradiators,SOthattheantennacallavoidpotentialinterferencewithsomespecialfrequencybands.2.AnovelmuRistepmonopoleantennaisproposed.MethodofmultistepfeedingisadoptedtomakeSUrethatthecurrentiscontinuousatthefeedingdistrictan
7、dtheimpedancematchingisimproved.Bothofuponantennas剮『csimulatedbynumericalsoftware.Furthermore。thecircularmonopoleantennaisfabricatedandmeasured.Thetheoreticalbroadbandcharacteristicsareverifiedbytheexperimentalresults.TheresultsshowthatbothoftheproposedantennasCallbeusedinUWBsystems.