An energy-efficient design for multihop relay network adopting CC-HARQ scheme

Abstract

This paper investigates the energy-efficient design of a multihop relay network adopting the Chase Combining based Hybrid Automatic Repeat reQuest (CC-HARQ) scheme with sum power constraint from a cross-layer perspective. We aim at maximizing the energy efficiency (EE) in the multihop relay network by jointly optimizing the payload length and average transmission energy per bit over all hops, with no limitation on the total number of (re)transmissions times. The theoretical findings are verified by simulations and the impacts of various parameters, e.g., the modulation and coding scheme (MCS) levels, channel gains and transmission distance, on EE are studied in detail. The results demonstrate that significant energy saving can be achieved by the proposed joint optimum algorithm.