User's Manual

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AdvancedRFTechnologies,Inc.  63
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‐ TheattenuationandDLoutputALClevelfortheotherportsaresetbasedontheformulabelow
tokeepthepowerratiobetweenBCUports.
 The maximum output power for the specified path = 10*log10[10^(Max_ALC/10)x(Pwr_Ratio)/
Max_Ratio]
 Max_ALC:DLoutputALClevelforthepathwithmaximumpower
ratio=5dBm
 Pwr_Ratio:TargetedDLoutputpowerratiovalueforthespecifiedpath
 Max_Ratio:maximumpowerratiovalue
 Theattenuationforthespecifiedpath=Thetargetedmaximuminputpowerforthespecifiedpath‐
Themaximumoutputpowerforthespecifiedpath
 DL outputALC
level = The targeted maximuminputpowerforthe specified path‐The attenuation
forthespecifiedpath
 ThepathforAT&T‐CH2
 Themaximumoutputpower=10*log10[10^(5/10)x20%/50%]=1.02dBm
 The ATT value = 18.0dBm‐1.02dBm=16.98dB  16.5dB(the control step of used attenuator is
0.5dB)
 DLoutput
ALClevel=18dBm–16.5dB=1.5dBm
 ThepathforSprint‐CH1
 Themaximumoutputpower=10*log10[10^(5/10)x30%/50%]=2.78dBm
 TheATTvalue=9.0dBm‐2.78dBm=6.22dB6.0dB(thecontrolstepofusedattenuatoris0.5dB)
 DLoutputALClevel=9.0dBm–6.0dB=3.0dBm
‐ TheDLmaximumoutputpowerofBCUisthesumofmaximumoutputpowerforeachportand
thispowerbecomestheHERFUinputcommissioninglevel.
‐ ThemaximuminputlevelofHERFUshouldbelessthan10dBm(=5dBm+10*log10(3))because
themaximumoutputof
BCUpereachpathdoesn’texceed5dBmbyALCfunction.
Table7‐10 MaximumOutputPowerpercarrier
WSP Sprint AT&T VZW
Targetedmaximuminputpower
9.0dBm 18.0dBm 11.0dBm
19.2dBm
TargetedDLOutputPowerRatiosetbyuser 30.0% 20.0% 50.0%
DLmaximumoutputpower
(ATTcontrolstep,0.5dBisnotconsidered)
2.78dBm 1.02dBm 5.0dBm
ATTvalue 6.0dB 16.5dB 6.0dB
DLoutputALClevelor
DLMaximumoutputpower
(ATTcontrolstep,0.5dBisconsidered)
3.0dBm 1.5dBm
5.0dBm
8.2dBm(RFUDLInputcommissioninglevel)
DLOutputPowerRatio
consideringATTcontrolstep0.5dB
30.37% 21.50% 48.13%
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