Error Probability Minimization of Multi-hop Relaying System in the Finite Blocklength Regime

Multi-hop relaying is a promising technology to enhance the system performance, especially for the scenario with a long distance wireless transmission or a direct transmission link having terrible channel fading. In this paper, we study a multi-hop relaying network operating with finite blocklength codes. We provide a joint system design with respect to the relay selection, power control and blocklength allocation with the aim to minimize the overall error probability. An integer non-convex optimization problem is formulated accordingly. By applying a tight approximation of the overall error probability, the problem is reformulated as an integer convex problem which can be efficiently solved. Via simulation, we validate the convex properties and provide the insight for the relay selection based on variant system setups.