Statistical QoS-Aware Precoding Scheme in the Finite Blocklength Regime

In this paper, a downlink multi-user multiple-input multiple-output (MU-MIMO) system subject to quality of service (QoS) constraints in the finite blocklength (FBL) regime is considered. Block fading channel is assumed and the precoding matrix for the multi-block transmission under perfect causal channel state information (CSI) is analyzed. Initially, a weighted sum effective capacity (SEC) maximization problem is established and subsequently the first-order optimality condition that the precoding matrix must fulfill is derived. Subsequently, a fixed point iteration algorithm is proposed to derive a feasible solution. Through simulation results, the superiority of the proposed scheme compared with other benchmark schemes is validated.