A Differential Chaotic Bit-Interleaved Coded Modulation System Over Multipath Rayleigh Channels

In this paper, a novel differential chaotic bit-interleaved coded modulation (DC-BICM) system is proposed for band-limited transmission. This system combines protograph-based low density parity check codes with constellation-based M-ary differential chaos shift keying (DCSK) modulation by one bitwise interleaving. Bit error rate simulation results show that the system has higher coding gain compared with the constellation-based M-ary DCSK modulation system with the same spectral efficiency over multipath Rayleigh fading channels. At the same time, several simulations and P-EXIT analysis are used to analyze the performance of the proposed system. It is found that there is a lot of room for optimization of the system by comparing decoding thresholds and simulation results. Moreover, the system with only partial channel state information has better performance and lower complexity compared with the traditional bit-interleaved coded modulation (BICM) directsequence-spread-spectrum system. As a result, the DC-BICM system is a good candidate for band-limited transmission.