Multi-hop Wake-up Control for On-demand Wireless Sensor Networks Exploiting Wake-up Receivers

Abstract

This paper focuses on on–demand wireless sensor networks (WSNs) where a main radio interface (IF) used for data communications by each node is remotely activated through its secondary radio called wake–up receiver. The energy–efficiency achieved by on–demand WSNs highly depends on the trade–off between the wake–up range (i.e., the range within which a wake–up signaling is possible) and power consumption of wake–up receiver. With larger (smaller) wake–up range, the required number of hops for data delivery can be smaller (larger) while larger (smaller) power consumption of wake–up receiver is required to achieve higher (lower) receiver sensitivity. In this paper, we analyze the impact of this trade–off on the overall energy–efficiency of on–demand WSNs. Furthermore, we propose a multi–hop wake–up control with small control overhead, which is achieved by making intermediate nodes jointly send several control messages for wake–up operations with a single transmission. Our simulation results reveal the inherent trade–off between sensitivity and power consumption of wake–up receiver, and also show that the proposed multi–hop wake–up control significantly improves the energy–efficiency of on–demand WSNs.