Analysis of Actual Transmitted Power from Hundreds of FR2 Radio Base Stations over One Month in Urban Areas in Japan

This study analyzes the actual transmitted power from 5G beamforming radio base stations (BF-RBSs) to clarify the effectiveness and issues of an actual maximum approach specified in the International Electrotechnical Commission 62232:2025. The actual maximum approach is a new compliance assessment method for electromagnetic field exposure levels from BF-RBSs based on time-averaged transmitted power. In this study, the actual maximum transmitted power every 5 or 30 min from more than 400 BF-RBSs using millimeter waves in urban areas in Japan was collected using a network management system over a period of one month. For each BF-RBS, normalized actual transmitted power was derived as the ratio of actual to configured maximum transmitted power. As a result of this measurement, the maximum value of normalized actual transmitted power was approximately −3 dB when the number of sets of user equipment (UEs) in the BF-RBS was less than two with high data traffic. Moreover, statistical analysis results of the measurement data shows that the actual maximum approach may underestimate the electromagnetic field exposure levels from a BF-RBS with three or fewer UEs when the actual transmitted power of the BF-RBSs is not monitored and controlled to maintain a level below the threshold.