Citation: Weber, M.; Fersi, G.;
Fromm, R.; Derbel, F. Wake-Up
Receiver-Based Routing for Clustered
Multihop Wireless Sensor Networks.
Sensors 2022, 22, 3254. https://
doi.org/10.3390/s22093254
Academic Editor: Alessandra
Rizzardi
Received: 19 March 2022
Accepted: 21 April 2022
Published: 23 April 2022
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Article
Wake-Up Receiver-Based Routing for Clustered Multihop
Wireless Sensor Networks
Maximilian Weber
1,
* , Ghofrane Fersi
2
, Robert Fromm
1
and Faouzi Derbel
1
1
Smart Diagnostic and Online Monitoring, Leipzig University of Applied Sciences, Wächterstrasse 13,
04107 Leipzig, Germany; robert.fromm@htwk-leipzig.de (R.F.); faouzi.derbel@htwk-leipzig.de (F.D.)
2
Research Laboratory on Development and Control of Distributed Applications (ReDCAD),
National Engineering School of Sfax, University of Sfax, Sfax 3038, Tunisia; ghofrane.fersi@redcad.org
* Correspondence: maximilian.weber@htwk-leipzig.de
Abstract:
The Wireless Sensor Network (WSN) is one of the most promising solutions for the
supervision of multiple phenomena and for the digitisation of the Internet of Things (IoT). The
Wake-up Receiver (WuRx) is one of the most trivial and effective solutions for energy-constrained
networks. This technology allows energy-autonomous on-demand communication for continuous
monitoring instead of the conventional radio. The routing process is one of the most energy and time-
consuming processes in WSNs. It is, hence, crucial to conceive an energy-efficient routing process.
In this paper, we propose a novel Wake-up Receiver-based routing protocol called Clustered WuRx
based on Multicast wake-up (CWM), which ensures energy optimisation and time-efficiency at the
same time for indoor scenarios. In our proposed approach, the network is divided into clusters. Each
Fog Node maintains the routes from each node in its cluster to it. When a sink requires information
from a given node, it’s corresponding Fog Node uses a multicast wake-up mechanism to wake up the
intended node and all the intermediate nodes that will be used in the routing process simultaneously.
Measurement results demonstrate that our proposed approach exhibits higher energy efficiency and
has drastic performance improvements in the delivery delay compared with other routing protocols.
Keywords:
WSN; wake-up based sensors; clusters; multicasting; IoT; routing; latency-minimisation;
energy-efficiency
1. Introduction
The Internet of Things (IoT) is developing towards a significant and extensive technol-
ogy. The vision of a global infrastructure of connected physical objects interacting anywhere
and anytime is still one of the emerging concepts in the IT world. Due to their robust design
and self-organising networking without the need for extensive infrastructure, Wireless
Sensor Networks (WSNs) are the backbone of IoT. They are increasingly used in different
applications, e.g., for monitoring and data transmission in areas such as structural and
environmental monitoring [
1
,
2
]. Further, healthcare, as well as smart home applications,
such as real-time indoor air quality monitoring [
3
] and on-demand indoor localisation [
4
,
5
],
are realised through this technology in a cost-effective and low-maintenance way. WSN is
also becoming increasingly important in indoor scenarios where accurate and reliable infor-
mation about people’s activities and behaviour is collected and disseminated to support
assisted living in home environments [
6
,
7
]. The provision of wireless sensors for use in
the sense of IoT is accompanied by various technical challenges [
8
]. Energy consumption
is the most important challenge since the lifetime of each sensor is tightly related to its
energy-critical battery. Thus, new ways must be found to increase the energy-efficiency
of sensors.
One of the major drawbacks of recent wireless sensors is the power consumption of
Radio Frequency (RF) transceivers with approximately 10–30 mA for routing processes or
radio transmissions. In order to allow an energy autarkic operation, a duty-cycled approach
Sensors 2022, 22, 3254. https://doi.org/10.3390/s22093254 https://www.mdpi.com/journal/sensors
