Outage Performance of Incremental Relaying Networks with OFDM Subcarriers Mapping Schemes

The scarcity of radio resources coupled with the high data rate demands in the last few years, induced incremental relaying techniques one of the most promising technologies. This is simply because it allows reaping spatial diversity and saving the channel resources at the same time. In this contribution, we make use of the Decode and Forward incremental relaying technique in OFDM cooperative systems by proposing and analyzing two subcarrier mapping algorithms. Based on outage probability, diversity order and power gain analysis, we derive the optimal parameters for these algorithms to enhance the outage performance of DF cooperative system by reducing the effect of error propagation. Also, an incremental relay sharing scheme is proposed allowing multiple sources to share the same relay and results in an improved spectral efficiency, which is critical given the high cost and scarcity of RF spectrum driven by the growing big data.