Sink-Based Centralized Transmission Scheduling by Using Asymmetric Communication and Wake-Up Radio

Abstract

In large-scale wireless sensor networks (WSNs) for wild environments, nodes once deployed run only on battery. Moreover, nodes close to a sink consume energy more quickly than other nodes due to packet forwarding. Mobile sink is a good solution to this issue, although it causes two new problems to nodes: (i) overhead of updating routing information and (ii) in-creased operating time due to aperiodic query. To solve these problems, this paper proposes an energy efficient data collection protocol for mobile sink, where sink-based centralized transmis-sion scheduling (SC-Sched) is realized by using asymmetric communication and wake-up radio (WuR). Specifically, nodes do not update route information. Instead, the sink determines the transmission order. In addition, each node is equipped with a WuR. At the time that a packet transmission between two nodes is scheduled, the sink transmits a wake-up message using a large transmission power, directly activating both nodes simultaneous-ly to communicate. Extensive simulation evaluations confirm that the proposed method is more energy efficient than conventional methods, reducing energy consumption to 1#x002F;9 in a WSN with 600 nodes. This method is further enhanced to deal with frame loss caused by multipath fading, improving frame delivery rate meanwhile suppressing energy consumption and data collection time.