Reducing EMF exposure from WSNs using transmission scheduling

Summary There is increasing pressure from the public to study the effects of electromagnetic field exposure and reduce this exposure for future networks or, at the least, keep it at a constant level. According to the World Health Organization, no link has been found between low levels of exposure to radio waves (as emitted by WiFi devices or mobile phones) and adverse health effects, but reducing exposure has other benefits besides public acceptance, such as reduced interference and improved network performance. Wireless sensor networks (WSNs) have rarely been studied from an exposure point of view, but their continuing expansion as part of the new Internet of Things vision is slowly bringing them to the spotlight. This work presents a novel evaluation of WSN emissions, using the Exposure Index proposed by the Low EMF Exposure Future Networks (LEXNET) project. Together with this evaluation, a method of reducing exposure by intelligently scheduling WSN transmissions is also proposed. The scheduling method is evaluated using a proposed scenario (compatible with evaluations of other technologies performed in LEXNET) both from a theoretical perspective and in a practical implementation, and results are compared with a baseline solution. Copyright © 2017 John Wiley & Sons, Ltd.