An Improved IBOC Scheme Based on BICM-STBC

In-Band on-Channel (IBOC) broadcasts digital audio signals simultaneously with analog Amplitude Modulation (AM) programs in the AM band. The transmit capacity has reached its limitations for the bandwidth, thus, enhancing digital transmission becomes a key technology in IBOC system. Bit-interleaved coded modulation (BICM) can provide spatial diversity without occupying high bandwidth. Meanwhile, space-time block code (STBC) , the technique of temporal diversity, is applied to raise transmission reliability. Based on spatial and temporal diversity, a scheme that STBC is embedded in MIMO-BICM, can add the reliability and effectivity of transmission over Rayleigh fading channels. In this paper, BICM-STBC instead of the conventional in IBOC would result coding gains and implicative transmit capacity progressively without increasing the bandwidth. The simulation results show when BER is below 10^-4, the improved channel coding scheme can achieve more than 2 dB coding gains.