MM-015039-001
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re-synchronization data from the Control Point via the MUX. This information, along with the voice
packets routed through the Ethernet Switch’s MLAN connection, is reunited to form the P25 transmitter
messages. Final synchronization of the P25 transmitter packets, relative to the required system/site
timing, is performed and the data is sent to the TX module(s). The BBP module manages only the control
operations for the TX modules. Inbound receiver communications from mobile and portables is
processed in the associated channel’s Traffic Controller and sent to the Control Point via the MLAN
connection to the Cisco
®
switch.
4.3.4.2
Heartbeat Messaging
Heartbeat messaging is used to monitor the condition of the TX, RX, and HPA modules. Once
operational, the BBP module sends out
heartbeat
messages to each module. When a heartbeat message is
received by a module, the receiving module then sends a heartbeat message back to the BBP module.
The heartbeat monitor task keeps track of the time-stamps of the received heartbeat messages. A fault is
registered if a heartbeat message is not received within a predetermined time-frame. The heartbeat
monitor also keeps track of certain fault conditions.
4.3.4.3
Resynchronization
In P25 Simulcast mode of operation, the MASTR V BBP module performs timing and resynchronization
of data packets sent to the TX module. A predetermined time delay is applied to the packets relative to a
precision world time clock signal provided by an external, centre highly stable, GPS based time clock. A
GPS receiver is installed at each Simulcast TX Site and Control Point to provide the best possible
synchronization between all TX sites.
Table 4-9: BBP Module Connections
LOCATION
CONNECTOR
DESCRIPTION
Rear Panel
SMA
10 MHz Time Base Input
DB-15HD
Simulcast Channel 1
DB-15-HD
Simulcast Channel 2
RJ-45
Ethernet MLAN
95-Pin
Backplane Small Signal Connector (5X19)
3-Pin
Backplane DC Power (refer to
Table 4-2
)
Circuit Board (side)
RJ-45
Factory Service Port (Signaling)
4-Pin
Factory Service Port (DC Power)
Front Panel
USB
Field Service Communications Port
Table 4-10: BBP Module – Front Panel Indicators and Controls
INDICATOR/CONTROL
INDICATOR COLOR
DESCRIPTION
Reference LED
Off
No Power
Green Solid
BP Clock Controller
Green Flashing
BP Clock Standby
Red Solid
External Reference
Failed