Blockage levels are first translated into {TAIL ~ transmission link parameters}, from which {HEAD ~ the methods} of bit rate reduction, increasing modem density, or system bandwidth, or higher encoding rate are derived 
from are derived
Blockage levels are first translated into { TAIL ~ transmission link parameters } , from which { HEAD ~ the methods } of bit rate reduction , increasing modem density , or system bandwidth , or higher encoding rate are derived
OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH REL OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH REL REL