Low-decoding-complexity TDM coded modulation with unequal error protection

For time-division-multiplexed coded modulation schemes with unequal error protection (UEP) proposed in the literature, the receiver requires several independent Viterbi decoders to decode all classes of data. A new UEP coded modulation scheme is proposed which has the advantages that decoding can be done by using a single slightly modified Viterbi decoder and that good coding gains can still be provided. Some new codes are presented with a rate of four bit/2D and percentage of important data ranging from 31.25 to 72.92%, which find potential applications in the envisioned digital broadcast of high-definition television signals. Excellent coding gains from 5.4 to 7.2 dB for the important data, as verified by simulations, can be provided with our scheme by using only eight-state codes