User Guide

CCS Technical Documentation System Module and User Interface
Company confidential NPL-3
Issue 1 3/03 ãNokia Corporation. Page 39
RF Frequency Plan
RF frequency plan is shown below. The VCO operates at the channel frequency multiplied
by two or four depending on the frequency band of operation. This means that the base-
band modulated signals are directly converted up to the transmission frequency and the
received RF signals directly down to the baseband frequency.
Figure 18: RF Frequency plan
HELGA
PLL
26 MHz
VCTCXO
f
f/2f/4
f
3420-
3980
MHz
925-960
MHz
880-915
MHz
I-signal
1805-1990
MHz
f
f/4
f
f/2
Q-signal
I-signalI-signalI-signal
RX
TX
I-signal
Q-signal
1710-1910
MHz
HELGO
824-849
869-894
3290
-