Ericsson MINI-LINK TN R3 ETSI - 4.7 Transmit Power Control

MINI-LINK TN R3 ETSI
The Diversity switches will work autonomous and are controlled by the switch
logic in the active MMU Rx. The switch logic is implemented as software in the
DP in the Control and Supervision block.
The Diversity switch will react on the Early Warning (EW) signals, Input Power
threshold alarm and FEC error alarm. The switch logic in one MMU needs
information from the other MMU, which is sent over the BPI bus.
Note that this switching is done under no fault conditions.
The switching principles are illustrated in Figure 74 on page 84.
Radio Frame
Multiplexer
Modulator
Cable
Interface
TDM
Multiplexer/
Demultiplexer
TDM PCI
RAU A
Node
Processor
MMU A
NPU
RAU B
TDM Rx
Switch
BPI
BPI
6667
Switch
Logic
Diversity
Switch
Radio Frame
Multiplexer
Modulator
Cable
Interface
TDM
Multiplexer/
Demultiplexer
MMU B
Diversity
Switch
Switch
Logic
Control and
Supervision
Control and
Supervision
Figure 74 Radio Segment Protection and Rx Equipment Protection
4.6.2.4 Rx Equipment Protection
This protection case involves two types of switch, TDM Rx switch and Diversity
switch.
The TDM Rx switch is a logical switch used to switch over the traffic to the
redundant MMU, in case of a failure in the TDM Demultiplexer part of the active
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/1555-CSH 109 32/1-V1 Uen B 2007-09-14