User Manual

1
Chapter 1 Introduction
ThismanualcontainsbothguidelinesonhowtodesignasystemusingtheDeltaNodefiberdistributedantenna
system(Fiber‐DAS)conceptandhowtoinstall,commissionandmaintainsuchasystemforthelifespanoftheentire
installation.Itwillalsocontainmanybitsofinformationregardinggeneralpracticesin
theindustryaswellasother
information.
Whenothermanufacturershaveconvertedoff‐airrepeatersintofiber‐fedrepeaters,DeltaNodehasdevelopedthe
conceptfromscratchwithfiberdistributioninmindfromthestart.Thisallowsforextremelygoodradio
performanceandweareproudofthebestinclassnoisefigureoflessthan3dBfor
thewholesystem,remoteunit
antennaporttobasestationinterfaceport.
TheFiber‐DASfromDeltaNodeisalsoextremelyflexibleinitssolutionmeaningthatthesystemcanbetailoredfor
almostanyneeds.Becauseoftheflexibilitytherearealsomanyparametersthatcanbechangedbytheuser.This
manualattemptstoexplainnotonlywhattheydo,butalso
howtosetthemproperly.
Fiber-DAS calculator — TogetherwiththismanualyoushouldhavetheaidoftheFiber‐DAScalculator,thisisan
Excelspreadsheetwiththefollowingfeaturesgivingameasureonhowwellthesystemwillperform:
SystemNoiseFigurecalculator
Intermodulationperformancecalculator
Uplink/DownlinkBalance
Dynamicheadroom
RF on fiber
Afiberdistributedantennasystem(Fiber‐DAS)isaveryefficientwayoftransmittingradiosignalsoverlarge
distances.Uptoabout25kmoffiberbetweenthehead‐endandtheremoteunitisallowed,providingthattheradio
accesstechnology(RAN)donotsuffertimingissuesandthatthe
fiberlossiswithinthespecification.
Themainprincipleistouseaninfra‐redlightsourcewhichismodulatedwiththecombinedradiosignalsthatneeds
tobepropagated.Thefiberchannelsystemisultrawide‐band,rangingfrom88MHzupto2600MHzandthus
coveringmosttypesofradiocommunicationsystemssuchas
FMbroadcast,VHFcommunicationradios,TETRA, 
GSM,CDMA,WCDMAandotherradioaccesstechnologiesthatareavailable.
Thedynamicofthefiberisgoodenoughtotoler atemulti‐carrier,multi‐bandandmulti‐operatorsolutionsthisway,
butofcoursetheyallsharetheavailabledynamicsandifthereareaverylargenumberofcarriersthefiber
attenuationneedstobelookedatofcourse.
BecausemostlandmobileradiosystemsandcellularsystemsareusingFrequencyDivisionDuplex(FDD)thismeans
thatthereneedstobeeithertwoseparatefibers,onefortheuplink(signalsfromtheterminaltowardsthebase
station)andforthedownlink(signalsfromtheradiobasestationtowardstheterminal)
ortheymaybemultiplexed
onthesamefiberusingdifferentwaveleng ths.
DeltaNodeFiber‐DASusewave‐lengthdivisionmultiplexing(WDM)asthenormalconfigurationfeaturingthe
following:.
Singlemodefiber
Angledconnectors
Opticalloss<15dB
Note: SeparateUL/DLfiberscanbeusedifitisnecessaryordesired.
Becausethemodulationisanaloguethesystemrequiresthefiberstobeofsinglemodetype.Allconnectorsusedin
DeltaNodeequipmentforFiber‐DASareofSC‐APCtypewitha7°angle.Itisveryimportantthatallconnectorsin
patchesetceterabetweentheMasterUnit(MU)and
theRemoteUnit(RU)areangled,otherwisereflectionsare
causedwhichwillcauseproblemswiththequality ofthesignalsthroughthesystem.