Assessment of Population Exposure to Electromagnetic Fields Due to Systems That Implement Dynamic Spectrum Sharing Between 4G and 5G: Definition of Methods and On-Site Measurements

Dynamic Spectrum Sharing (DSS) is a technique that allows different systems, namely 4G LTE and 5G NR, to coexist in the same frame. It is a smart solution for the rapid deployment of the new mobile system over the existing network while building the new dedicated infrastructure. Interleaving of different protocols within the same frame, however, requires that maximum-power extrapolation techniques that have already been validated for 4G and are still under development for 5G are checked for correctness of results when applied to the new transmission scenario.This paper investigates this topic through an experimental approach in different sites where different DSS systems were implemented. Results show that the same tools and methods already developed for LTE signals can be used to estimate maximum exposure levels by DSS systems and that the implementation of DSS does not affect exposure significantly. Moreover, it was also verified that methods for measuring 5G NR signals available in the literature can be applied to DSS signals, obtaining exposure estimates that are fully compatible with those obtained with the methods developed for LTE.