A PARAFAC-based Channel Estimation Algorithm for Multi-user MIMO Two-way Relay Systems

Abstract

In this paper, the authors present a novel channel estimation method for multi-user multiple-input multiple-output (MIMO) two-way relay systems using parallel factor (PARAFAC) model. The proposed method transmits interactive orthogonal channel training sequences at each user end, the relay uses different amplifying factors to amplify the received signals, and forward the amplified signals to users. Finally, the PARAFAC model is constructed at each user end and this PARAFAC model is fitted to estimate all the channel matrices. The proposed method has higher channel estimation accuracy. Moreover, the method can estimate all the channel matrices at each user. Numerical examples are shown to demonstrate the effectiveness of the PARAFAC-based channel estimation algorithm.