Error Probability Analysis for Rectangular Differential OFDM with Index Modulation over Dispersive Channels

In this paper, a novel forgetting factor aided rectangulardifferential (RD) orthogonal frequency division multiplexing(OFDM) with index modulation (IM) is proposed fordispersive channels, which amalgamates the concept of RDcoding for exploiting the benefits of OFDM-IM with the absenceof channel state information (CSI). To be more specific, Nsubcarriers are partitioned into G subblocks for IM mapping.By employing RD coding during two adjacent subblocks, noncoherentdetection without CSI can be carried out at the receiver.To further improve the performance, a novel forgetting factor isexploited at the receiver, which can be optimized via a closedform without extra complexity. Based on the derived forgettingfactor, the upper bound of the average bit error probability(ABEP) of the proposed RD-OFDM-IM scheme is derived andis validated by the simulation results. Both the theoretical andsimulation results indicate that the proposed RD-OFDM-IMscheme is capable of providing a considerable performance gainover its conventional differential OFDM (D-OFDM) counterpart