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Wander Limits at PDH Outputs

For the sake of completeness, the wander limits at PDH outputs have been included. It can be seen by comparison with the limits at a SEC output that at short observation intervals, synchronisation signals delivered via PDH are permitted to have higher TDEV corresponding to more underlying noise at relatively high frequencies within the range of interest[*].This is indicative of the fact that it is the interim period in which PDH and SDH networks co-exist that puts the largest strain on the synchronisation network.

The above result in the masks shown in figures 2.13 and 2.14.

 
Figure 2.19:   Maximum wander at PDH outputs in TDEV
\begin{figure} \centerline{ \epsfig {file=eps/pdhreftdevmask.eps, width=10cm} }\end{figure}


 
Figure 2.20:   Maximum wander at PDH outputs in MTIE
\begin{figure} \centerline{ \epsfig {file=eps/pdhrefmtiemask.eps, width=10cm} }\end{figure}


Mark J Ivens
11/13/1997