User manual

ADCP-75-154 • Issue 3 • August 2006
Page 2
© 2006, ADC Telecommunications, Inc.
The MHU may be any of the three types shown. One PDU may support multiple MHUs of the
same frequency. Each MHU requires one Bias-T. The ClearGain system also includes power
cables and alarm cables.
1.2 Functional Description
The basic purpose of a ClearGain tower mounted amplifier system is to amplify the uplink
signal just after the antenna. This is done to compensate for the loss in signal strength that
occurs in passage of the signal through the coaxial cable to the Base Transceiver Station (BTS)
at the base of the tower. The ClearGain system also provides alarming and lightning protection.
Figure 2 depicts how the system components are involved in system function. As shown:
Figure 2. System Function
Power Distribution Unit
MHU
DISCONNECT MHU 1ALARMINPUT
+ Ð
MHU 2 MHU 3 MHU 4 MHU 6MHU 5
OKFAI LCOMNO NC OK OK OK OK OK
BASE
STATION
21487-A
ClearGain PDU
COAXIAL CABLE
TO ANTENNA
COAXIAL
CABLE
RF SIGNALS
POWER
JUMPER
CABLE
SITE
ALARM
MHU
DC POWER
FAULT DETECTION
DC POWER
FAULT DETECTION
ANTENNA
ANT
FILTER/LNA
UPLINK
DOWNLINK
BTS
MHU
GROUND
RX/TX (A)
GROUND
BTS ANT
DC
Bias-T kit
Freq: 800 - 2200MHz
Temp: -40 to +65 C
Input: 5 to 24VDC
Max Current: 2A
P/N: 1344027
S/N: XXXXXXXXX
Date: YYYY/MM/DD
ASSEMBLED IN
KOREA