Functional Description - Panasonic EB-X300 Service Manual

5.1.3. Functional Description

Frequency Plan
The frequency plan is shown below:
TX Frequency Plan
E-GSM 900
GSM 1800
PCS 1900
F
VCO
Where k is 1 for low band and 2 for high band.
Fractional-N
PLL
General
RF circuit design is built based on the direction conversion transceiver IC integrated by SAW filters (U1201), power amplifier with
control circuit, and Transmitter/receiver switch.
RF LO always requires external frequency sources with VCTCXO. The LO is frequency is adjusted periodically to synchronise
with the network cell frequency.
Antenna
EB-X300 uses a Helical-type monopole antenna which is optimised for operation on GSM, DCS and PCS bands.
TX Frequency
880.2 MHz - 914.8 MHz
1,710.2 MHz - 1,784.8 MHz
1,850.2 MHz - 1,909.8 MHz
RX RF from
LNA
3
= F
RX
2k
F
VCO
UHF VCO
Figure 5.2. Receiver Block Frequency Plan
TX IF
88.46 MHz - 114.35 MHz
90.316 MHz - 1,04.776 MHz
97.379 MHz - 1,12.341 MHz
F
RX
90°
x 1
/3
x 2
k = Frequency multiplier
– 5-3 –
TX RF LO
1,459.59 MHz -1,543.725 MHz
1,354.737 MHz - 1,414.482 MHz
1,460.684 MHz - 1,516.606 MHz
RX I
90°
x 2
RX Q