A Better Decision Rule for OFDM with Subcarrier Index Modulation

Orthogonal frequency division multiplexing with subcarrier index modulation (OFDM-SIM) is a promising technique which has been proposed and developed recently. Unlike the conventional OFDM system, the indices of the subcarriers in this new system are also utilized for transmitting the information bits. The On-Off Keying (OOK) is employed to control the subcarrier status. This innovative structure leads to a better trade-off between the system performance and energy efficiency. Meanwhile, the peak to average power ratio (PAPR) is decreased with this enhanced system. Therefore, finding the status of the carrier correctly is critical. In this paper, a new decision rule for determining the subcarrier's status is proposed and evaluated. And the analytical bit error rate (BER) expression of the OFDM-SIM system with this new decision rule is derived either.