Optimal power splitting for SWIPT-based MIMO DF relay systems

In this paper, we consider “harvest-then-use” based simultaneous wireless information and power transfer (SWIPT) for cooperative relay transmission, where a multiple-input multiple-output (MIMO) relay adopts decode-and-forward (DF) relaying strategy for information forwarding. By considering practical power splitting (PS) relay receiver architecture, joint optimization problem of power allocation and determining power splitting ratios is formulated to maximize the end-to-end achievable rate. Using the Lagrange dual method, we develop the efficient algorithm to find the optimal solution. Several valuable insights are provided via theoretical analysis and simulation results.