User manual
DTS Broadcast   PDH Microwave Digital Radio User Manual 
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3 Options 
3.1 Protection Systems 
The L54 Digital Microwave Radio linking is operated in protected 
configuration by the addition of an indoor rack-mounted protection switching shelf and another standby 
radio terminal. 
The ODU arrangements may use either one antenna with a waveguide coupler or two antennas. 
The switching protection shelf may be operated in one of three modes: 
Hot-Standby 
Only one transmitter is on-line at any one time. Both main and standby terminals are tuned to the 
same frequency. 
A fault detected in the on-line radio terminal results in a switch of traffic to the off-line radio 
terminal. 
The ODU arrangements may use either one antenna with a waveguide coupler or two antennas. 
Frequency Diversity 
The main and standby radios are transmitting simultaneously and are tuned to different 
frequencies to avoid interference. A fault detected in a traffic-carrying radio terminal results in a switch 
of customer traffic to the standby radio link. 
The ODU arrangements may use either one antenna with a waveguide coupler or two antennas. 
Space Diversity 
The main and stand-by radios are set up in Hot Stand-by mode, but are connected to their own 
antennas. The spatial separation of the antennas, combined with hitless receive switching, provides the 
Space Diversity function on the receiving end of the link. 










