Backward Alarms; Ibs Fault Conditions And Actions - Radyne DMD20 Installation And Operation Manual

DMD20/DMD20 LBST Universal Satellite Modem Maintenance and Troubleshooting

6.1.2.3 Backward Alarms

Backward Alarms are alarms that are fed back to or received from the other end of the satellite
link. In IBS Mode (including Drop & Insert), Backward Alarm 1 is the only one used. It would be
received if the distant end demod drops lock.

6.2 IBS Fault Conditions and Actions

Figure 6-10 and Table 6-4 illustrate the IBS Fault Conditions and Actions to be taken at the Earth
Station, at the Terrestrial Data Stream, and the Satellite. These faults include those detected on
the Terrestrial link and those detected from the satellite.
Figure 6-10. IBS Alarm Concept
TM103 – Rev. 2.5 6-7