Device-to-Device Relaying Scheme based on Message Passing Algorithm in the Uplink Cellular System

Multi-hop transmission using relays in wireless communications is a technology that can improve transmission reliability by reducing transmission distance of individual links. We propose a multi user relaying scheme based on device-to-device (D2D) transmission in the uplink cellular system. Specifically, a signal transmission technique and a decoding scheme based on message passing algorithm are developed to improve both the spectral efficiency and transmission reliability. Two cases of resource allocation for the proposed D2D relay system are considered: one case of allocating fewer resource blocks than the number of users and the other case of allocating the same number of resource blocks as the number of users. Simulation results confirm the advantage of the proposed relaying scheme in terms of the spectral efficiency and bit error rate.