Sdh Trib Ports - Harris Stratex Eclipse 4.6 User Manual

SDH Trib Ports

The IDU 155o supports one STM1/OC3, optical tributary. The connectors are SC type,
and cable options are available, as accessories, for extension to SC, FC or LC types.
The receive-level range is -31 dBm (max sensitivity) to -7 dBm (max input power).
Transmit output is within limits of -15 dBm to -8 dBm.
For protected operation optical splitter Y-cables are available to provide extensions
from SC to SC, FC or LC connectors.
The SDH optical line code is Binary Scrambled NRZ (Non Return to Zero).
Auto Insertion of AIS or PRBS on Tribs
When a link demodulator-unlock occurs, it inserts an alarm signal (AIS or PRBS15) on
all trib circuits towards the customer. (Demodulator unlock may occur under severe
fading or an equipment fault).
• For all E1 or DS1, tribs AIS is inserted.
• For STM1/OC3 tribs a PRBS15 pattern (15 bit pseudo-random bit sequence) is
inserted.
An on-board master clock maintains customer-facing clocking references when the
expected signal input and associated clocking reference from its link is missing, or
below the minimum level required.
AIS/PRBS15 may be forced onto a tributary using the Systems Control
screen.
E1 Trib Performance Monitoring
A CRC (Cyclic Redundancy Check) function is supported on the DAC module in the
IDU GE 2ox and IDU 300 20xV2 to provide a background error performance indicator
for a selected E1 trib circuit.
The check process accesses the G.704, CRC4 Multiframe, which is a background error
check function provided between devices operating with G.704 framing.
• The circuit being monitored must be end-to-end terminated on framed-rate
multiplexers, or similar, to generate the G.704 framing, which includes the CRC
function. In other words, the circuit supported by the IDUs must be operational for
user traffic to provide the multiframe needed for the monitoring process.
• The errors detected by the monitoring process are circuit errors. That is, they may
have been generated by any device within the circuit, which includes all upstream or
downstream devices from the IDUs.
• Separate monitoring options are provided for upstream and downstream traffic
directions.
• Traffic on the selected trib is not affected.
For more information, refer to E1 Trib Performance on page 13-22 of Volume IV.
260-668066-001 Rev 024 February 2009
Eclipse User Manual
Vol. II-2-5