The protected US5Ge is a modular system consisting of a rack mounted chassis containing plug-in modules. The chassis is designed to be installed in a 19, 23 inches or ETSI telecom rack bay. All system connections are made on the front panel.
Input connections are made via a bi-impedance connector for each input; namely DB9 for 120 Ohm impedance and the type BNC or 1.6/5.6 for 75 Ohm impedance.
Output connections are made via DB25 connectors for 120 Ohm impedance directly on the US5Ge Main shelf.
For Outputs with 75 Ohm impedance additional patch panel are provided with i.e. BNC, 1.6/5.6, BT connectors.
Module access for service/replacement is performed from the front of the shelf using “quick release” locking fasteners.
Output cards are inserted in the so-called POUT slots (protected outputs slots) and are therefore protected pair by pair (1+1 protection).
If one card fails, the other card placed in the same POUT slot takes the relay. As draw in the block diagram, in the protected mode the connection panel output adaptor panel combines the outputs of the paired modules. The output port in normal operation has a signal presence supplied simultaneously from each of the paired modules. If there is a hardware fault on one of the modules, the unaffected module maintains a consistent signal level to the NE. The same process occurs when one port fails or the entire module is removed, therefore there isn’t any phase jump perturbation.
Therefore, each Network Equipment (NE) is connected to the SSU on a pair of output cards that are bridged at the shelf level. The structure is fully redundant and each NE is connected to the SSU on a pair of output cards.
This configuration is the ideal configuration when the number of outputs and/or the distance between the SSU and the NE is important.