{HEAD ~ Data} on the interleave path is interleaved by {TAIL ~ interleaver} if an interleave depth is >2 
{ HEAD ~ Data } on the interleave path is interleaved by { TAIL ~ interleaver } if an interleave depth is > 2
HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH REL REL REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH