Lessons Learned from a Distributed RF-EMF Sensor Network

Abstract

Overview

In the contemporary era of ubiquitous wireless communication, the need for effective spatiotemporal monitoring of radiofrequency electromagnetic fields (RF-EMF) is growing—both to mitigate public concern and to understand exposure levels better. This study presents the design and implementation of an affordable RF-EMF sensor system spanned across an urban setting.

Methodology

• Design of a low-cost RF-EMF sensor node capable of monitoring four essential wireless telecommunication frequency bands with high temporal precision.
• Deployment of these nodes in a dual configuration: stationary on building facades and mobile on postal vans.
• Collection of nearly 10 million samples from January 2019 to May 2020.

Findings

Analysis of data from fixed sensor nodes highlighted the drawbacks of slower sampling rates, such as one sample every 15 minutes, and shorter monitoring periods like several weeks. A 30-minute sampling interval was found adequate for capturing diurnal and weekly patterns while maintaining important short-term variations.

Correlation analysis between sensor nodes suggests an optimal density of 100 nodes per square kilometer for future networks. Mobile sensors pinpointed potential RF-EMF high-exposure zones over an expansive area exceeding 60 square kilometers.

Conclusion

This pioneering study leverages a small yet robust number of sensor nodes to offer critical insights for future distributed RF-EMF sensor networks aimed at reducing exposure risks and addressing public health concerns.