Design of Efficient Joint eIRA-Coded MSK Modulation Systems for Space Communications

An efficient scheme of extended irregular repeat-accumulate (eIRA-) coded minimum shift keying (MSK) is presented. Based on an extrinsic information transfer (EXIT) chart, it is designed as an eIRA code, incorporating a continuous-phase encoder (CPE) decomposed from MSK. Our scheme and a contrasting scheme of another eIRA-coded MSK are simulated in an additive white Gaussian noise (AWGN) channel. Simulation results show that our scheme outperforms the contrasting scheme by about 2 dB at a bit error rate (BER) of and has the same performance of an optimal eIRA-coded binary phase shift keying (BPSK). In addition, our scheme obtains lower complexity and less decoding latency because all differential encoders in the eIRA code are eliminated, while adding some differential decoders. Thus, the two-level Tanner graph-based decoding in the contrasting scheme is reduced. Therefore, the proposed scheme can be efficiently applied to satellite and deep space communications.