Bit-interleaved turbo-coded noncoherent orthogonal modulation with iterative demodulation and decoding: capacity limits and convergence analysis

This paper studies bit interleaved coded modulation (BICM) using noncoherent orthogonal modulation (e.g. NFSK). To improve performance, information is fed from the decoder back to the demodulator, using the recently proposed strategy known as BICM with iterative demodulation (BICM-ID). The capacity of noncoherent orthogonal modulation under BICM constraints is compared against that with joint demodulation and decoding (which BICM-ID approximates). Also, the convergence behavior of iterative demodulation with turbo decoding is investigated by using density evolution.