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