LG VX9100 Service Manual page 29

VX9100
1.2 Description of RX Part Circuit
1.2.1 Quintplexer (DP100)
The Quintplexer consists of the Rx bandpass filter (BPF), the Tx BPF and the GPS filter (BPF) which has the
function of separating Tx, Rx and GPS signals in the full Triplex system for using the common antenna. The Tx part
BPF is used to suppress noises and spurious out of the Tx frequency band. The Rx BPF is used to receive only Rx
signal coming from the antenna, which is usually called preselector. It's main function is to limit the bandwidth of
spectrum reaching the LNA and mixer, attenuate receiver spurious response and suppress local oscillator energy. As
a result frequency sensitivity and selectivity of mobile phone increase. The specification of VX9100 Quintplexer
described below;
PCS band
Pass Band
Insertion Loss
Return Loss
Attenuation
Cellular band
Pass Band
Insertion Loss
Return Loss
Attenuation
GPS band
Pass Band
Insertion Loss
Return Loss
Isolation1
Isolation2
Copyright © 2007 LG Electronics. Inc. All right reserved
Only for training and service purposes
Tx
1850.5~1909.5 MHz
3.9 dB max
9.5 dB min
40 dB min
(1930.5~1989.5MHz)
Tx
824~849 MHz
2.6 dB max
9.0 dB min
40 dB min
(869~894MHz)
1574.42~1576.42MHz
1.9 dB max
9 min
50 dB min(Cell Tx à GPS)
45 dB min(PCS Tx à GPS)
Rx
1930.5~1989.5 MHz
4.2 dB max
9.0dB min
50dB min
(1850.5~1909.5MHz)
Rx
869~894 MHz
3.4 dB max
9.0dB min
55dB min
(824~849MHz)
- 28 -
Tx to Rx (min)
53 dB (1850.5~1909.5MHz)
40 dB (1930.5~1909.5MHz)
Tx to Rx (min)
55 dB (824~894MHz)
40 dB (869~894MHz)
LGE Internal Use Only