User's Manual

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-10dBm 10dB
7.5 Input power limit function (TX Input ALC)
The DAS has TX input ALC function at the BIU to limit level when input power is
increased above level by operated input AGC function
Normally, there are more than two input port in the MDBU of BIU
For example, 850cellular band has two input port to support both VzW and AT&T
Two input power may be different each other. The DAS have input attenuator in first
stage of MDBU. Through input AGC function, input ATT is adjusted according to input
power. If input power increase, input ATT is adjusted again to limit increased input
power. Also, if input power decrease input ATT return to initial ATT
7.6 Optic loss compensation
The DAS has the function of automatically compensating for optical loss. It can do the
work for up to 5dBo of optical loss. Set “TX OPTIC COMP” of ROU as "ON." Optical
compensation of ROU can not be made without communication with such units in
upper level as ODU or OEU. For 1dBo of optical loss, basic TX OPTIC ATT is 12dB; for
5dBo of optical loss, TX OPTIC ATT is 4dB. OPTIC COMP works only one time before
it stays dormant.
The figure below shows a screen for OPTIC Information in ROU GUI.
LD POWER means output level of ROU Laser Diode, which is sent to a upper unit by
ROU. PD POWER means input level of Photo Diode to be received from a upper unit.