Network modulation (NeMo)-aided OFDM incremental relay systems

In this paper, we propose the new incremental relaying scheme using network modulation (NeMo) concept in OFDM-based systems. We first introduce how to integrate NeMo to OFDM incremental relay and show how both cooperative diversity and frequency diversity can be achieved on incremental relaying schemes. From the simulation results, it is confirmed that NeMo enables OFDM incremental relay to enjoy the frequency-selective diversity from grouping and subcarrier interleaving and to partially obtain the cooperative diversity gain for all the symbols, which is different from the conventional incremental relaying method. By increasing the NeMo modulator size, it is shown that the diversity gain is also increased causing the performance improvement in term of bit error rate.