Ericsson MINI-LINK E, Техническое описание

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MINI-LINK E and E Micro
3.3.2.1 DC/DC Converter
The DC/DC converter provides stable voltages for the microwave sub-unit.
3.3.2.2 Cable Interface
The incoming composite signals from the indoor units, that is, transmitting IF
signal, command and control signal and DC, are demultiplexed in the cable
interface and forwarded for further processing.
• The transmitting IF signal is a modulated signal with a nominal frequency
of 350 MHz.
• The command and control signal up-link is an ASK (Amplitude Shift Keying)
modulated signal with a nominal frequency of 6.5 MHz.
• The DC feed is in the range of 45 – 60 V DC (24 – 60 V DC, nominal,
is connected to the MMU).
Similarly, the outgoing signals are multiplexed in the cable interface: receiving
IF signal and command and control signal down-link.
• The nominal frequency of the receiving IF signal is 140 MHz.
• The command and control signal down-link is an ASK modulated signal
with a nominal frequency of 4.5 MHz.
In addition to the above, the cable interface includes an overvoltage protection
circuit.
3.3.2.3 Control and Supervision Processor
The microwave sub-unit houses the processor for control and supervision of the
radio unit. The main functions of this processor are described below.
Alarm Collection
Collected alarms and status signals from the radio unit are sent to the indoor
MMU processor. Summary status signals are visualized by LEDs on the radio
unit.
Command Handling
Commands from the indoor units are executed. These commands include
transmitter activation/deactivation, channel frequency settings, output power
settings and RF loop activation/deactivation.
Radio Unit Control
The processor also controls the radio unit’s internal processes and loops.
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AE/LZT 110 2012 R8C 2002-03-04