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INSTALLATION GUIDE FOR RA-7800
RA-7800 QI
Copyright - refer to title page
Page 15
ENU Status : 1-0-1
2 EQUIPMENT DESCRIPTION
2.1 SYSTEM
DIAGRAM
GSM 1800
WCDMA 2100
DL Adapter
UL Adapter
Optical Tx/Rx
Combiner
E/O
O/E
Uplink
Downlink
MCU
PC
Distribution
Board
Power
Input
Fig 3: MOU System diagram
Fig 4: RU System Diagram
As shown in the above figures, the combined signals as GSM1800 and WCDMA2100 from the BTSs
are received and converted into optical signals after amplification in the MU, and then the optical
signals are transmitted to the RU via optical fiber. In the RU, the optical signals are converted into
electrical signals. After being amplified, the signals are transmitted to the customer’s mobile phone via
service antenna.