In this letter, we consider the interleaver design in bit-interleaved coded modulation (BICM) with low-density parity-check (LDPC) codes. The design paradigm is to provide more coding protection through iterative decoding to bits that are less protected by modulation (and are thus less reliable at the output of the demodulator). The design is carried out by an ad hoc search algorithm over the column permutations of the parity-check matrix. Our simulations show that the proposed reliability-based coded modulation scheme can improve the error-rate performance of conventional BICM schemes based on regular LDPC codes by a few tenths of a decibel, with no added complexity.

Bit-interleaved coded modulation (BICM), Coded modulation, Low-density parity-check (LDPC) codes, M-ary phase-shift keying (M-PSK), Nonbinary modulation, Reliability-based coded modulation
doi.org/10.1109/TCOMM.2006.869865
IEEE Transactions on Communications
Department of Systems and Computer Engineering

Maddock, R.D. (Robert D.), & Banihashemi, A. (2006). Reliability-based coded modulation with low-density parity-check codes. IEEE Transactions on Communications, 54(3), 403–406. doi:10.1109/TCOMM.2006.869865