2
Figure 1-5. Internal View, NSU2 Control Unit
1.1.2 FUNCTIONAL
The MITEQ 1:N New Switchover Unit (NSU) is designed to provide improved reliability
for advanced satellite communications systems. The NSU consists of a Control Unit,
Switch Modules and frequency converters. The Control Unit monitors the status of up to
twelve primary frequency converters and one backup frequency converter. When a fault
is detected on a primary frequency converter, the defective converter is automatically
placed into standby and the backup converter is placed on line in place of the defective
converter using the Switch Modules. The frequency converters can be prioritized so that
critical communication channels have access to the backup converter on a prioritized
basis.
Switchover from a defective primary converter to the backup converter is achieved by
connecting the converters to a switch matrix. The defective converter is replaced by
physically removing its input/output signal lines and connecting them to the backup
converter via the switch matrix. This ensures continuous operation while the fault is
corrected, or allows for routine maintenance without disrupting signal transmission.