Power-and-Index based Multiple Access for V2X Networks

High reliability is one of the key requirements for the future fully connected autonomous vehicles. This paper proposes a novel highly reliable multiple access technique for Vehicle-to-Everything (V2X) networks. The proposed technique uses Index Modulation (IM) in conjunction with Non-Orthogonal Multiple Access (NOMA), which significantly improves the performance of detection at the receiver side. It also benefits from superimposed IM with repetition coding and power allocation factor in V2X networks. We investigate mapping rules for IM-aided NOMA for multiple vehicles. Performance evaluation in this paper shows that both diversity order and power gain can be improved if the proposed scheme is deployed, resulting in a lower probability of index and symbol errors in presence of sparsely activated sub-carriers compared to Orthogonal Multiple Access (OMA) or NOMA.