4 4 8 0 1 2 3 0 1 2 3 0 1 2 3 0 1 2 3 0 4 2 6 5 1 3 7 3 7 5 1 This is generated by the 1/2 AWGN code (5 7) operated twice, ie, (xk+1 xki) [xk-1 xk-2] -> [xk+1 xki]. We also puncture the first (MSB) bit and Gray map the symbols. intermediate states: 00 21 02 23 00 21 02 23 10 31 12 33 10 31 12 33 output before puncturing: 00 31 03 32 30 01 33 02 13 22 10 21 23 12 20 11 output after punturing the MSB: 00 11 03 12 10 01 13 02 13 02 10 01 03 12 00 11 and in decimal: 0 5 3 6 4 1 7 2 7 2 4 1 3 6 0 5 After Gray mapping: label -> phase 0 -> 0 1 -> 0 2 -> 7 3 -> 2 4 -> 5 5 -> 4 6 -> 6 7 -> 3 0 4 2 6 5 1 3 7 3 7 5 1 2 6 0 4