Towards a Crowdsourcing-Based EMF Exposure Monitoring: Evaluation of Smartphone Measurements Using Kriging

Conventional methods for exposure assessment cannot provide comprehensive and continuous monitoring. A crowdsourcing-based approach relying on the signal strength measurements of common smartphones could be a potential solution. This paper deals with the evaluation of measurement data collected with smartphones under conditions similar to crowdsourcing. Kriging is used to interpolate and smooth the noisy measurement data. The smartphone measurement data is analyzed for three LTE cells and compared with codeselective measurements of a field strength meter. It is shown that areas with high and low exposure can be distinguished and that local hot spots can also be detected. Furthermore, it becomes clear that at least a rough estimate of the electric field strength can be derived from the signal strength measurements, provided that enough smartphone readings are available for this area.