User's Manual

FiberDistributedAntennaSystem(FiberDAS)
97
Uplink
1. Setallva
luesatdefault(factorsettingmayvaryduetoindividualtestingbeforeshipping)forallbands
a. BIU:‐10
dB
b. FOI:‐6,‐6,‐6
c. FOR:+12
d. Amp:+35fo
rlowlossfiber,+45forhighlossfiber
2. Startwithad
justingthehighfrequencyband.
3. TurnRFonattheBIU
.EnsurethatonlytheRFstripsbeingusedhaveRFturnedon.
4. GototheFO
RandturntheULtesttoneon.Notethelevelbeingtransmittedandthefrequency.Thelevelisset
atthefactorytocompensateforlossesbetweentheRUoutputportandtheamplifier.Levelswillvaryunitby
unit.
5. Connectsp
ectrumanalyzertotheBIUBTSportandtunetotheULtesttonefrequency.
6. Measurethetestto
nelevel.InitialgoalshouldbetosettheULtesttoneattheBIUBTSport tothesamelevel
asbeingtransmittedattheRU(zerodBsystemgain).
a. Tored
ucegain,itisrecommendedtoadjusttheattenuatorsintheBIUULpath.Thiswillfurther
reduceULnoise.
b. Toinc
reasegain,itisrecommendedtoadjustthegainintheRUULpath.
Note: DonotdrivetheFO
RULlaserwithmorethan0dBmRFinput.RecommendedFORULinputlevel
isapproximately‐5dBm.
c. TheBIUULin
putwillbeperman entlydamagedwithsignalsstrongerthan+13dBm.
7. RecordULte
sttonelevelreceivedinthespectrumanalyzer.AfterallremoteunitsonthesectorhaveULlevels
set,theremoteswillneedtobebalancedagainsteachother(allarehittingtheBTSULatthesamelevel).
Levelsshouldbewithinabout1d
Bofeachother.
Downlink
1. Setallva
luesatdefault(factorsettingmayvaryduetoindividualtestingbeforeshipping)
a. BIU:‐15
dB
b. FOI:‐3,‐3
c. FOR:+10
d. Amp:Tobesetba
sedonactualinput
2. Suggestion:Se
tFORDLALCleveltoonedBlessthanampratingifunitalarmsonDL.
a. A43
dBamplifierwouldhaveanALClevelsetto+42.
3. SetBIUDLlev
eltocompensateforICUinterconnectionloss.Donotex ceed+10dBoutputoftheBIUintheDL
path(willcauseIM).
a. Suggestset
tingatmaximumof+5dBoutputoftheBUI.
b. Notether
eis13dBofinherentlossintheBIU.With0dBsettingsintheBIUDLattenuatorsa30dB
inputsignalwillhaveanoutputof+17dB(30dBinputminus13dBinherentloss=17dB).Adjust
attenuatorsso thatBIUisapproximately+5dBasastart.
c. VariationsintheBT
Sinputlevelsforloadingmustbetakingintoconsideration.Fullloadandnoload
powerlevelsdiffergreatly.DonotallowtheBTStooverdrivetheBIU.
4. AdjustFO
IattenuatorlevelsintheDLpathsothattheRFinputintotheDLlaserisapproximately‐5dB.
a. Notetha
tthe0dBmaxintothelaserisacompositelevelforallbands.Bysettingeachbandat‐5dB
thentotalcompositeshouldnotexceed0dB.
b. Takein
toconsiderationthateachBIUhastwoRFstrips/paths.Thesemustbetakenintoconsideration
whensettingtheFOIlevels.
c. Calculatefulllo
adconditionsforallbandsbeingfedintotheFOI.Incorrectlysettingthelevelswill
impactthesystemduringtimesofmostusage.
5. Setthede
siredgainintheremote.