Ceragon FA4800, Руководство пользователя

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Using More than One HSS Unit Chapter 10
FA4800 User Manual Release 1.9.30 10-6
4. To add a a further HSS unit: Connect the next available SYNC
port from the second HSS unit in descending order (SYNC 5 in
Figure 10-7 ) to SYNC 1 of the third HSS unit.
5. ODUs are connected to the third HSS unit from SYNC 2 as shown
in Figure 10-8 , in ascending order:
Figure 10-8: Cascading three HSS units
6. If further ODUs are required, observe the convention that
additional even numbered units are populated in descending
order from SYNC 9 and odd numbered HSS units are populated
in ascending order from SYNC 2.
Condition 2: Total HSS Cable Length
The total path of the HSS sync pulse must not exceed 300m. This applies no
matter how many HSS units are used. To illustrate the method for calculat-
ing the sync pulse path length we show three examples. For our purpose,
let:
L
mn
denote the length of the ODU-HSS unit cable at SYNC n on HSS unit
m
H
m
be the length of the cable joining HSS unit m to HSS unit m+1
One HSS unit with five collocated ODUs
Two cascaded HSS units as shown in
Figure 10-7
Note
If an ODU is disconnected from an HSS unit, then all remaining ODUs must
be moved up or down to maintain the connectivity.
PathLength L
11
2 L
12
2 L
13
×
+
×
2 L
14
L
15
+
×
+ + =
PathLength L
11
2 L
12
2 L
13
2 L
14
×
+
×
2
+
L
15
×
+
×
H
1
2 L
29
2 +
×
L
28
2 + L
27
×
L
26
+
×
+
+ +
=