PAMS Technical Documentation
TFK–2 Series Transceiver
Chapter 3
TRANSCEIVER
OVERVIEW
Original 05/98
TFK–2
PAMS
Transceiver Overview
Technical Documentation
CHAPTER 2 – TRANSCEIVER OVERVIEW
Contents
Introduction Page 3–3
Block Diagram of External Connections Page 3–3
Modes of Operation Page 3–4
Circuit Description Page 3–4
Block Diagram Page 3–5
Power Distribution Page 3–5
Page 3–2
Original 05/98
PAMS
TFK–2
Technical Documentation
Introduction
The TFK–2 is a radio transceiver unit for the GSM 1800 network. It is a GSM
1800 power class 1 transceiver providing 16 power levels with a maximum output power of 1 W.
The transceiver consists of a Radio module (WT7) and assembly parts.
The small–size SIM (Subscriber Identity Module) card is located inside the
phone.
Block Diagram of External Connections
Landline
telephone
connector
G3 fax
connector
Transceiver Overview
Antenna 1
connector
Antenna 2
connector
2
1
RADIO MODULE
1
WT7
2
Power supply
connector
2
20
5
System
connector
SIM
Original 05/98
Page 3–3
TFK–2
PAMS
Transceiver Overview
Modes of Operation
There are three different operation modes
– idle mode
– active mode
– local mode
In the idle mode transmitter is in OFF–stage.
In the active mode all the circuits are supplied with power although some parts
might be in the idle state part of the time.
The local mode is used for alignment and testing.
Circuit Description
The transceiver electronics consist of one integrated Radio Module (RF block +
System block + LA block). Accessories are connected to the transceiver via a
system connector or RJ–11 connectors.
Technical Documentation
The System blocks provide the MCU and DSP environments, Logic control IC,
memories, audio processing, RF control hardware and 2 to 4 wire interface for
the landline telephone. On board power supply circuitry delivers operating voltages for both System and RF blocks. On board LA power unit generates feeding voltage and ringing voltage for the landline telephone.
The general purpose micro–controller, Hitachi H8/3001, communicates with the
DSP, memories and Logic control IC with an 8–bit data bus.
The RF block is redesigned for a Fixed Wireless–terminal which operates in the
GSM1800 system. The purpose of the RF block is to receive and demodulate
the radio frequency signal from the base station and to transmit a modulated
RF signal to the base station.
Page 3–4
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PAMS
TFK–2
Technical Documentation
Block Diagram
BPF
DUPLEX
FILTER
RX
RX
SYNTE
SYNTE
TX
TX
IF 13 M
Clk 13 M
AFC
TXC
TXI,TXQ
Transceiver Overview
FBUS
SIM
SYSTEM
ASIC
RFI2
Clk
13 M
Clk
13 M
Clk
13 M
MCU
Clk 512 k, Clk 8 k
DSP
PCM
C
O
D
E
C
M2BUS
RS232
LA CONTROL
2TO4
Tx
WIRE
INTER–
FACE
Rx
2W
2W
RF BLOCK
Power Distribution
The power supply is based on the ASIC circuit PSCLD. The chip consists of
regulators and control circuits providing functions like automatic power up, reset and watchdog functions. External buffering is required to provide more current.
Automatic power up is needed because there is no ”power on”–button on the
terminal so whenever power supply is connected to the terminal it will start automatically power up procedure. If the input voltage is too high or too low the
terminal will automatically shut off and when the voltage is in correct window it
will start automatically power up procedure.
Charging control is not supported.
RF CONTROL
SYSTEM BLOCK
DBUS
Original 05/98
Page 3–5
TFK–2
PAMS
Transceiver Overview
Technical Documentation
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