A power saving dual-hop architecture based on hybrid spatial modulation

In this paper, we propose a novel Dual-Hop Decode-and-Forward (DF) architecture based on Multiple-Input Multiple-Output (MIMO) Zero Forcing (ZF) precoding and Spatial Modulation (SM) that employs a centralized or a distributed detection algorithm at the Relay Nodes (RNs). Using Tikhonov Regularization (TR) we form a precoding technique that turns out to reduce significantly the transmitted power at the Source Node (SN) under certain scenarios. Moreover, the use of TR enables our scheme to communicate in channels with low and medium correlation at the first hop without a Bit Error Rate (BER) penalty. Finally, we extend our scheme in order to take into account realistic Channel State Information (CSI) at the the Source Node (SN).