Scalar Measurements of 5G mm-Wave EMF Power in NLoS Propagation

We present a methodology for on-site measurements of electromagnetic fields (EMFs) exposure of 5G base stations (BSs) operating in the millimeter-wave (mm-wave) frequency range (24.5-52.6 GHz) that extends the one introduced by the authors in previous work to mm-wave frequencies and Non-Line-of-Sight (NLoS) propagation. The impact of omnidirectional and directional antennas on measurements in the new measurement conditions is examined. This investigation marks the first instance of such a comprehensive analysis. Results indicate that measurement techniques devised for frequencies below 6 GHz under Line-of-Sight (LoS) conditions can generally be applied in the mm-wave range. However, in an NLoS scenario, it is suggested that omnidirectional antennas are employed, as directional ones require an initial evaluation to align the probe with the direction of the strongest signal. This work has significance for standardization bodies developing methodologies to measure exposure from new-generation mobile network BSs.