Saud Althunibat , Ziyad Al Tarawneh IET Communications,2019, 13: 3278-3284. https://doi.org/10.1049/iet-com.2019.0137 Abstract: Most of the energy consumed in target-detection wireless sensor networks (WSNs) is due to the decision gathering process. As such, several energy-efficient decision gathering schemes have been proposed to improve energy efficiency. In this study, a new multi-hop decision gathering scheme for target-detection WSNs is presented. The proposed scheme creates paths to gather the nodes' decisions, where each path includes a set of nodes. Nodes in the same path cooperate to deliver their decisions by using multi-hop transmissions. At each hop, the relay node combines the received decisions with its own decision and uses a higher modulation order to forward them to the next node in the path. Two different setup scenarios are considered to evaluate the proposed scheme, namely, fixed transmit power scenario and fixed bit error rate scenario. In the former scenario, results demonstrate that the proposed scheme achieves better error rate at short hop distances when compared to the conventional single hop scheme. On the other hand, results of the fixed bit error rate scenario show that a significant amount of the saved power can be attained by the proposed scheme with a slight loss in the decision error rate.