Harris Constellation, Руководство по эксплуатации системы

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Constellation® January 2006
3-12 Constellation Radio Configurations
Figure 3-14: OC-3/STM-1 to OC-3/STM-1 Configuration
Radio Synchronization Configuration
The High Level Mux (HLM) cards for 8, 16, and 28 DS1 radios, as available in
a repeater configuration, can be set for either Through timing or Source timing.
Through timing mode minimizes the jitter accumulation on DS1s directly
passing through multiple repeaters.
In a loop system with all repeaters, at least one repeater needs to be set for
Source timing. In large systems, the HLM cards in repeater configurations need
to be set for Source timing after 15 consecutive repeaters to clear the
accumulated jitter.
The HLM cards in a terminal configuration are always set for Source timing.
If Source timing is selected, the Service Channel must be configured with Local
Off Hook enabled.
MUX
MODEM
OC3/STM-1
RF
RF
OC3/STM-1 Terminal OC3/STM-1 Terminal
MUX
MODEM
The HLM-155 unit can be either protected or unprotected in hot
standby Constellation terminals, depending on whether the OEM
multiplexer is protected
.
OC3/STM-1