ITU-T K.56 (07 2003) (英) Protection of radio base

INTERNATIONALTELECOMMUNICATIONUNIONITU-TK.56TELECOMMUNICATIONSTANDARDIZATIONSECTOROFITU(07/2003)SERIESK:PROTECTIONAGAINSTINTERFERENCEProtectionofradiobasestationsagainstlightningdischargesITU-TRecommendationK.56ITU-TRec.K.56(07/2003)iITU-TRecommendationK.56ProtectionofradiobasestationsagainstlightningdischargesSummaryThisRecommendationprovidesaquantitativeprocedureinordertoprotectradiobasestations(RBS)forwirelessaccessnetworkagainstlightningdischarges.ThelevelofprotectionisbasedonthetolerablefrequencyofdamagethatisassignedtotheRBSbytheoperator,consideringtheconsequencesofserviceinterruptionandlossofequipment.TheRBScoveredbythisRecommendationismadeupofashelterorsmallbuildingtohousetheequipmentandanearbytowertoholdtheantennas.Theprotectionproceduresincludeearthing,bonding,shieldingandinstallationofsurgeprotectivedevices(SPD).SourceITU-TRecommendationK.56waspreparedbyITU-TStudyGroup16(2001-2004)andapprovedundertheITU-TRecommendationA.8procedureon29July2003.iiITU-TRec.K.56(07/2003)FOREWORDTheInternationalTelecommunicationUnion(ITU)istheUnitedNationsspecializedagencyinthefieldoftelecommunications.TheITUTelecommunicationStandardizationSector(ITU-T)isapermanentorganofITU.ITU-Tisresponsibleforstudyingtechnical,operatingandtariffquestionsandissuingRecommendationsonthemwithaviewtostandardizingtelecommunicationsonaworldwidebasis.TheWorldTelecommunicationStandardizationAssembly(WTSA),whichmeetseveryfouryears,establishesthetopicsforstudybytheITU-Tstudygroupswhich,inturn,produceRecommendationsonthesetopics.TheapprovalofITU-TRecommendationsiscoveredbytheprocedurelaiddowninWTSAResolution1.InsomeareasofinformationtechnologywhichfallwithinITU-T'spurview,thenecessarystandardsarepreparedonacollaborativebasiswithISOandIEC.NOTEInthisRecommendation,theexpressionAdministrationisusedforconcisenesstoindicatebothatelecommunicationadministrationandarecognizedoperatingagency.CompliancewiththisRecommendationisvoluntary.However,theRecommendationmaycontaincertainmandatoryprovisions(toensuree.g.interoperabilityorapplicability)andcompliancewiththeRecommendationisachievedwhenallofthesemandatoryprovisionsaremet.Thewordsshallorsomeotherobligatorylanguagesuchasmustandthenegativeequivalentsareusedtoexpressrequirements.TheuseofsuchwordsdoesnotsuggestthatcompliancewiththeRecommendationisrequiredofanyparty.INTELLECTUALPROPERTYRIGHTSITUdrawsattentiontothepossibilitythatthepracticeorimplementationofthisRecommendationmayinvolvetheuseofaclaimedIntellectualPropertyRight.ITUtakesnopositionconcerningtheevidence,validityorapplicabilityofclaimedIntellectualPropertyRights,whetherassertedbyITUmembersorothersoutsideoftheRecommendationdevelopmentprocess.AsofthedateofapprovalofthisRecommendation,ITUhadnotreceivednoticeofintellectualproperty,protectedbypatents,whichmayberequiredtoimplementthisRecommendation.However,implementorsarecautionedthatthismaynotrepresentthelatestinformationandarethereforestronglyurgedtoconsulttheTSBpatentdatabase.ITU2003Allrightsreserved.Nopartofthispublicationmaybereproduced,byanymeanswhatsoever,withoutthepriorwrittenpermissionofITU.ITU-TRec.K.56(07/2003)iiiCONTENTSPage1Scopeandpurpose........................................................................................................12References.....................................................................................................................13Definitions....................................................................................................................24Abbreviations................................................................................................................25Referenceconfiguration................................................................................................26Needofprotection........................................................................................................37Probabilisticanalysis....................................................................................................47.1Tolerablefrequencyofdamage(Ft)...............................................................47.2Frequencyofstrikestothetower(Fa)............................................................57.3FrequencyofstrikestotheRBShousing(Fd)................................................57.4Analysisofthefrequencyofstrikes...............................................................58Determinationofthelightningcurrentparameters.......................................................69ProtectionproceduresinLPZ0.....................................................................................69.1Proceduresappliedtothetower.....................................................................69.2Earthingsystem..............................................................................................710Protectionproceduresforthecablesthatcomefromthetower...................................711Protectionagainstthelightningeffectsinsidethehousing..........................................811.1Shieldingfactor(η)..................