基站天线设计 知名制造商的设计水平 各公司产品的特点及优缺点.doc

《基站天线设计 知名制造商的设计水平 各公司产品的特点及优缺点.doc》由会员上传分享，免费在线阅读，更多相关内容在工程资料-天天文库。

1、EffectsofExposuretoGSMMobilePhoneBaseStationSignalsonSalivaryCortisol,Alpha-Amylase,andImmunoglobulinABiomedicalandEnvironmentalSciencesObjectiveThepresentstudyaimedtotestwhetherexposuretoradiofrequencyelectromagneticfields(RF-EMF)emittedbymobilephonebasestationsmayhaveeffectsonsalivarya

2、lpha-amylase,immunoglobulinA(IgA),andcortisollevels・MethodsFiftysevenparticipantswererandomlyallocatedtooneofthreedifferentexperimentalseenarios(22participantstoscenario1,26toscenario2,and9toscenario3).Eachparticipantwentthroughfive50-minuteexposuresessions.ThemainRF-EMFsourcewasaGSM-900

3、-MHzantennalocatedattheouterwallofthebuilding.Inseenarios1and2,thefirst,third,andfifthsessionswere"low"(medianpowerfluxdensity5.2pW/m2)exposure.Thesecondsessionwas“high”(2126.8pW/m2),andthefourthsessionwasFediurrT(153.6pW/m2)inseenario1,andviceversainseenario2.Seenario3hadfourulownexposu

4、reconditions,followedbya"high"exposurecondition.Biomedicalparameterswerecollectedbysalivasamplesthreetimesasession.Exposurelevelswerecreatedbyshieldingcurtains.ResultsInseenario3fromsession4tosession5(fromMlownto"high”exposure),anincreaseofcortisolwasdetected,whileinseenarios1and2,ahighe

5、rconcentrationofalpha-amylaserelatedtothebaselinewasidentifiedascomparedtothatinscenario3.IgAconcentrationwasnotsignificantlyrelatedtotheexposure・ConclusionsRF-EMFinconsiderablylowerfielddensitiesthanICNIRP-guidelinesmayinflueneecertainpsychobiologicalstressmarkers.Boundaryelementmodelin

6、gofradiobasestationantennasEngineeringAnalysiswithBoundaryElementsThepaperpresentsanaccurateandefficientboundaryelementprocedurefortheanalysisofradiationfrombasestationantennas.Thebasestationantennosystemisrepresentedbytheverticalantennoarrayinfrontofperfectlyconducting(PEC)groundplanere

7、flector.TheformulationoftheproblemisbasedonasetofcoupledPocklingtonintegro-differentialequationsforverticalantennaarray.ThissetofcoupledequationshasbeennumericallytreatedbytheindirectGalerkin-Bubnovboundaryelementmethod(GB-IBEM).Thenumericalresultsforthecurrentsinducedalo