RADWIN2000CPlusUserManual Release3.5.70 11‐1
Chapter11:
UsingtheRADWINGSU
Whatisitfor
TheGPS‐basedsynchronizationunit(GSU)isdesignedtohandleinter‐siteinterferences
underlarge‐scaledeploymentscenarios.
TheGSUisanoutdoorunitconsistingofasmallsizeenclosure,aGPSantennaandaPoE
device.
TheGSUisconnectedtotheHSSUnitusingastandardHSScable.Itsynchronizesthe
transmissiontimingofmultipleHub‐Sitestothesameclocksourcethuseliminatingmutual
interference.
GSUFunctionality
TheGSUreceivesasynchronizationsignalfromtheGPSoncepersecond.Itdistributesa
RADWINproprietarysynchronizationsignaltoallotherODUsusingtheRS422protocoland
thestandardHSSmechanism,wheretheGSUactsasanHSMunit.
WhentheGSUdoesn’treceiveasynchronizationsignalfromtheGPSfor30seconds,itmoves
automaticallytoSelf‐GenerationmodeandactsasaregularHSMunit,untiltheGPSrecovers.
TypicalGSUScenarios
IndependentDistributedSites
InthescenarioofFigure 11‐1,wehavemultipleindependentcollocatedsites,whichmay
interferewitheachother.Tomeetthissituation,wecoordinateallofthemusingtheGSUas
shown.
TheGSUfunctionslike“wideareaHSSunit”,ensuringthatallparticipatingradiosatthe
locationsmarkedGSUeachtransmitandreceiveatthesametime.