Receiver-Initiated Data Collection in Wake-Up Radio Enabled mIoT Networks: Achieving Collision-Free Transmissions by Hashing and Partitioning

To achieve ultra-low energy consumption and decade-long battery lifetime for Internet of Things (IoT) networks, wake-up radio (WuR) appears as an eminent solution. While keeping devices in deep sleep for most of the time, a WuR enabled IoT device can be woken up for data transmission at any time by a wake-up call (WuC). However, collisions happen among WuCs for transmitter-initiated data reporting and among data packets for receiver-initiated data collection. In this article, we propose three novel hashing-based schemes in order to achieve collision-free data transmissions for receiver-initiated data collection. We consider first a simple scenario where all devices in a region of interest are reachable by a WuC message and propose a scheme which facilitates a scheduled time instant for data uploading of each device through a hash function. In the second scenario where IoT devices are distributed across a large region that cannot be covered by a single WuC, we propose two partitioning algorithms to enable data collection across multiple partitions. Furthermore, we extend the scenario by considering device mobility and propose another scheme which improves the partitioning algorithm to deal with mobility. Both analysis and simulations are performed to demonstrate the effectiveness of the proposed schemes.