User Guide

NPL-3 Company confidential
System Module and User Interface CCS Technical Documentation
Page 48 ãNokia Corporation. Issue 1 3/03
Figure 22: Power amplifier
RF ASIC Helgo
The RF ASIC features include
- Package uBGA108
- Balanced I/Q demodulator and balanced I/Q modulator
- Power control operational amplifier, acts as an error amplifier
- The signal from VCO is balanced, frequencies 3420 to 3980 MHz
- GSM850 and GSM1800 low noise amplifier (LNA) are integrated.
The Helgo can be tested by test points only.
AFC function
AFC is used to lock the transceiver’s clock to the frequency of the base station.
Antenna
The NPL-3 GSM850/1800/1900 transceiver features an internal antenna.
EGSM
out
DCS/
PCS
out
EGSM
in
DCS/
PCS
in
Power
detector
EGSM
Power
control
DCS/PCS
Power
control
Mode
GSM850
GS
M1800
/
1900
GSM850
GS
M1800
/
1900
GSM850
GS
M1800
/
1900