Complexity reduced turbo-bit-interleaved coded modulation with iterative decoding

Spectral efficiency of turbo code can be improved by use of coded modulation methods such as bit-interleaved coded modulation (BICM) with iterative decoding (BICM-ID). On the other hand, the performance of the turbo-BICM can be further improved by iteratively exchanging information between a decoder and a demodulator within a receiver and this scheme is known as the turbo-BICM-ID. Unfortunately, the required complexity of the turbo-BICM-ID is much higher than that of the turbo bit-interleaved coded modulation with iterative decoding turbo-BICM-ID. In this study, the authors propose a complexity reduced turbo-BICM-ID by optimising the mapping of coded bits to modulation symbols and the amount of information fed back from the decoder to the demodulator.