Nokia 8850 Service Manual

Page of 54
NSM–2
System Module
PAMS Technical Documentation
Page  40
Issue 1  12/1999
 Nokia Mobile Phones Ltd.
RF Functional Description
Architecture contains one RF–IC, dualband PA module, VCO–module,
VCTCXO module and discrete LNA stages for both receive bands.
SHF
VCO
PLL
VCXO
13 MHz
to ASIC
TXP
I
Q
TXIP
TXIN TXQP
TXQN
AFC
RXREF
1.2 V
f
f/2
HAGAR
f
f/2
f
f/2
f
f/2
TXC
SERIAL
 CTRL
BUS
VREF_2
1.5 V
dual P
A
SA
W
BIAS
ANT
 SW
Diplexer
EGSM
PCN
EGSM
PCN
f
f/2
26 MHz
buf
fer