User Guide

Issue 1 12/04 COMPANY CONFIDENTIAL 27
Copyright © 2004 Nokia. All Rights Reserved.
RAE-6/RA-4
7 - RF Description and Troubleshooting Nokia Customer Care
■ Transmitter description and troubleshooting
The transmitter consists of:
• two final frequency IQ-modulators
• two power amplifiers, for the lower and upper bands separately
• power control loop.
The IQ-modulators are integrated in Honi, as well as the operational amplifiers of the power
control loop. The two power amplifiers are located in a single module with a power detector. In
the GMSK mode, the power is controlled by adjusting the DC bias levels of the power amplifi-
ers.
Power amplifier
The power amplifier features include:
• 50 ohm input and output, GSM850/EGSM900/GSM1800/GSM1900
• internal power detector
• EDGE mode
Figure 9: Power amplifier
RF ASIC Honi
The RF ASIC features include
• Package LFGBGA88
• 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 3296 to 3980 MHz
EGSM
out
DCS/
PCS
out
EGSM
in
DCS/
PCS
in
Power
detector
EGSM
Power
control
DCS/PCS
Power
control
Mode
EGSM900/GSM850
GSM1800
/
1900
EGSM900
GSM850
GSM1800
/
1900
EGSM900
GSM850
GS
M1800
/
1900