User's Manual

Table Of Contents
AR Standard Repeater BSel Repeater
044-05250 Rev A A-3
BSel Repeater
Figure A-3 BSel Repeater Blcok Diagram
Figure A-3 illustrates a block diagram of a BSel repeater. This diagram is applicable to
repeaters for e.g. GSM, TACS, ETACS, AMPS, DAMPS, CDMA and WCDMA systems. The
signal from the base station is received via the repeater donor antenna and is then forwarded
through a DC, used as antenna port only if an RF modem is used. The signal passes a DPX,
is amplified in a LNA, and enters the BSA.
The first mixer stage on the BSA, which is controlled by a synthesizer, converts the received
frequency down to the IF frequency. The signal is then filtered by SAW bandpass filters and
amplified before it is fed to the second mixer stage for conversion back to the original
frequency. The BSA has adjustable bandwidth and the SAW filter combination can be
software changed from OM-Online (or OMS).
The following PA is controlled by the CU. The amplifier gain will be reduced to avoid instability
due to poor antenna isolation. A detector on the PA measures the output level continuously.
The signal from this detector is used by the automatic gain control (AGC) to supervise and, if
necessary, reduce the output power to keep it under a maximum level. The AGC also affects
other amplification stages.
The output signal from the PA at P5 passes a DPX before it is fed to the repeater service
antenna.
MS –20dB
DC
BS
P130
P31
P33
TEST –30 dB
PA - DL
LNA - DL
PA - UL
LNA - UL
CSA - DL
DPX
CSA - UL
ALI / RCI
P130
DPX
BA
ANT DPX
HI
LO
ANT
ANT
HI
LO
IN OUT1 P101 P301
P4 P5 P3 P4
IN
OUT1
P101
P301
P4P5
MS –20 dB
RCU
RCI
PSU
MSC
WLI
P34/
P36
CU