A novel scheme of coding and modulation for digital television terrestrial broadcasting

In this paper high-coding-rate block turbo codes (BTC) are adopted in digital television terrestrial broadcasting (DTTB) to replace the conventional applications of serially concatenated codes. A new multi-resolution 64QAM constellation is designed for hierarchical modulation to offer three tiers of services with dedicated protection in one DTTB channel. In the receiver, the simulation result on fixed-point iterative turbo decoding algorithm based on MAX-LOG-MAP criterion is aided to develop the ASIC core. Simulation in terms of bit-error-rate (BER) on additive white Gaussian noise channel shows that the required E_b/N_O High priority stream is only 3.9 dB at the threshold of visibility, which makes it more competent for mobile and indoor reception or other error-sensitive services. At the same time, the medium and low priority streams can support fixed outdoor reception.