Studies On The Miniature Wideband Base Station Antenna

With the development of the communication technology, mobile communicationtechnology need be suitable to the higher standard and the communication systemmust deal with larger data capacity and ensure the communication quality and thespeed of data transmission. Base station act a important role in mobilecommunication and the performance of the base station antennas directly influencethe service quality of mobile communication. The base station antenna is developingtowards wideband, miniaturization and integration due to the request ofcommunication system. The property of the antenna depends on the performanceindex of the antenna, including radiation pattern, beam width, gain, bandwidth etc.The design of the antenna need not only achieve the requirement of the performanceindex, but also realize the miniaturization to resolve the problem of the site deficit ofthe base station on account of the enormous amount of base station.Microstrip antenna was applied different kind of field because of the merit oflow profile, small volume, light weight and integration with active circuit, while thedefect that its bandwidth is considerably narrow restricted its evolution for so long.This paper utilizes the advantage above and use the wideband technology of themicrostrip antenna to design a miniaturized wideband dual-polarized microstripantenna with technologies of cross slot coupling, stacked patches and two layers feeds.The feed line, dual offset microstrip line, and other technologies mentioned can notonly extend the bandwidth of the antenna, but also improve the stability of the inputimpedance. The dual layers feeds can decrease the size of the antenna and achieve agood isolation. The simulated and measured results demonstrate the performance ofthe antenna basically met the requirement of the antenna of3G base station.The dissertation firstly introduces the performance index of the antenna, chosenof the base station antenna, the analytical method of the microstrip antenna and thewideband technology of the microstrip antenna. Then we design a minimizedwideband microstrip antenna and simulate it. The sample exhibits a good simulationresults and the structure of the antenna was analyzed theoretically. Thirdly the antenna array is designed and simulated. Finally the entity of the minimizedmicrostrip antenna is fabricated and the compared results of the simulation, themeasured results indicate the measured result is closed to the simulated result throughthe measurement. The two ports bandwidths are40%and38.5%, respectively, whereits bandwidths cover over the3G frequency band.