User's Manual

ADCP-75-237 • Issue 1 • 8/2007 • Section 1: OVERVIEW
Page 1-2
© 2007, ADC Telecommunications, Inc.
1.1.2 Reverse(Up) Link
The reverse link and the forward link have a same structure. Frequency raging from 824 ~
849MHz received by the service antenna go into the duplexer. The duplexer removes all unwanted
signals and sends the specific signal to the LNA. The reverse link signal received by the LAN is
amplified by the drive amplifier and Down Mixer where IF signal conversion is done.
The IF signal then goes through IF SAW Filter adding two bands of 11+1.5MHz and
10+2.5MHz, totaling 25MHz, after filtering the signal. This signal now moves to up mixer to be
converted to the RF frequency and sent to a final stage amplifier. The signal in final stage
amplifier undergoes through duplexer. Then the signal goes through the donor antenna,
transmitting reverse link signal to base stations.
1.2 RF SIGNAL FLOW (1900MHz)
1.2.1 Forward(Down) Link
The base station signal ranging from 1930 ~ 1990MHz is received by the Donor antenna. It
passes through the duplexer removing the unwanted reverse path signals received by the LNA.
The forward link signal received by the LNA goes through a BPF (Band Pass Filter) then is
amplified by the drive amplifier. The signal than goes through the LNA and a Down Mixer
where IF signal conversion is done. This IF signal then goes through an IF SAW Filter adding
two bands of 15MHz and 5MHz, totaling 20MHz, after filtering the signal. This signal now
moves to an up mixer to be converted to the RF frequency and sent to a final stage amplifier.
The final stage amplifier's output power goes through the duplexer. The signal then goes
through the service antenna transmitting the forward link signal to the handsets.
1.2.2 Reverse(Up) Link
The reverse link and the forward link have the same structure. Frequencies raging from 1850 ~
1910MHz received by the service antenna go into the duplexer. The duplexer removes all
unwanted signals and sends the specific signal to the LNA. The reverse link signal received by the
LAN is amplified by the drive amplifier and Down Mixer where IF signal conversion is done.
The IF signal then goes through IF SAW Filter adding two bands of 15MHz and 5MHz, totaling
20MHz, after filtering the signal. This signal now moves to up mixer to be converted to the RF
frequency and sent to a final stage amplifier. The signal in final stage amplifier undergoes
through duplexer. Then the signal goes through the donor antenna, transmitting reverse link
signal to base stations.