A nested tensor-based receiver employing triple constellation precoding for three-hop cooperative communication systems

In this paper, we consider a three-hop amplify-and-forward (AF) relaying system employing triple constellation (TC) precoding independently at the source and relay nodes. The signals received at the destination form a fifth-order tensor satisfying a nested parallel factor (PARAFAC) model. Exploiting this nested structure, we derive two inner PARAFAC models and one outer PARAFAC model in terms of a TC coding scheme, which are then used to devise a tensor-based receiver allowing joint estimation of information symbols and individual channels. Simulation results show that the proposed receiver outperforms several competing tensor-based receivers, and operates close to the zero-forcing receiver with perfect channel state information.(c) 2022 Elsevier Inc. All rights reserved.