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10.4.2
Description of Reception Block Diagram
E-GSM band (925-960MHz).
Incoming RF signal from aerial is filtered and switched to the RX GSM path through SW700 . The signal is filtered by FL400 ,
before to be amplified by IC400 , and is further filtered by FL402. Then, the RF signal (925-960 MHz) is mixed with a frequency
(1150-1185 MHz) coming from the RF-PLL and controlled by the RF-VCO (IC602). For the channel 1, the output signal of the
mixer is 360 MHz (1285 MHz-925 MHz =360 MHz), and is filtered by FL405.
DSC band (1805-1880MHz).
Incoming RF signal from aerial is filtered and is switched to the RX DCS path through SW700 . The signal is filtered by FL401 ,
before to be amplified by IC400 , and is further filtered by FL403. Then, the RF signal (1805-1880 MHz) is mixed with a
frequency (1445-1520MHz)coming from the RF-PLL and controlled by the RF-VCO (IC602). For the channel 1, the output signal
of the mixer is 360 MHz (1805 MHz-1805 MHz =360 MHz), and is filtered by FL405.
For the E-GSM and DCS bands.
The single intermediate frequency is 360 MHz. Then, these frequency is filtered by FL 405.The IF is demodulated to Base Band
(IC300) I/Q phase demodulated signals. RF-IC (IC401) provides automatic gain control.
IC401 includes a quadrature demodulator using a divide by four technique for 90° phase splitter. The IF signal (360 MHz) is
demodulated to I, Q balanced signals for BBE.
10.5
Transmission.
10.5.1
Transmission Block Diagram.
ANT
Mecha
J400
SW
GSM SUPPLY
GSM 880-915Mhz
SW
SW700
DCS 1710-1785Mhz
DCS SUPLY
10.5.2
Description of Transmission Block Diagram.
The direct and phase shifted signals are then fed to I and Q modulators inside the IC401. I and Q data components are fed into
the IC401. The output from the two modulators is summed and fed out of
IC401.
E-GSM Band (880-915MHz).
A phase locked loop is created around the TXVCO IC700. The output is fed into IC401 and converted to 424 MHz by mixing
with RFVCO at 1304-1339 MHz. This 424 MHz signal is compared with the 424MHz signal from the modulators, and the error
signal is used to control the TXVCO. Note that the error signal on the IC700 input will have a DC component to control
frequency, and an AC component at approx 424 MHz to control phase changes. Then the signal is filtered, attenuated by a filter
allowing an impedance adaptation with the power amplifier IC701. From the PA, the output goes through coupler Z701, is
switched to the TX path and is filtered by SW700. The signal then goes up to the antenna.
Version A
Date: 05/02
20/22
X600
TCXO
13Mhz
RF VCO
IC602
Z701
Coupler
PA
Z700
IC701
Coupler
IC710
-
+:
Z.A. Pigeon Blanc, 35 370 St Germain du Pinel France
( :
FAX:
IF PLL
RF PLL
OSW
GSM
ATT 9dB
TX VCO
IC700
ATT 8dB
DCS
pin 25. The GMSK signal leaves the modulator of
Mitsubishi Electric Telecom Europe S.A.
After Sales Services
+33 (0)2 23 55 16 30
+33 (0)2 99 75 71 62
Service Manual
Trium 110
424 Mhz
/4
MOD
IC401
APCCNT
TXIP
TXIN
TXOP
TXON
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