PPT Slide
Trellis coded modulation (Ungerboeck, 1982) :coding specific to modulation scheme improves bandwidth efficiency
0000 1000 0100 1100 0010 1010 0110 1110 0001 1001 0101 1101 0011 1011 0111 1111
c1 selects the 1st set partition
c2 selects the 2nd set partition
c3 selects the 4rd set partition
c4 selects the 4th set partition
‘less protected’ bits are assigned to larger Euclidian distances
larger code rates with good error correction !