Abstract

Overview

Realistic human exposure to electromagnetic fields (EMF) in indoor environments is crucial for safety assessments, particularly with the rollout of newer technologies like 5G and 6G. This study evaluates the exposure at frequencies of 3.5 GHz and 28 GHz using a sophisticated hybrid method combining ray-tracing and finite-difference time-domain (FDTD) techniques.

Findings

• The study marks the first instance of calculating absorbed power density for distributed massive multiple-input multiple-output (DMaMIMO) 6G base stations at 28 GHz.
• Comparative analysis with 3.5 GHz 5G base stations reveals that computational costs are significantly higher at 28 GHz. However, due to speed enhancements, extensive analysis is feasible.
• Exposure levels in different setups showed that distributed base stations lead to 2 to 3 times lower exposure than collocated base stations when power is normalized.
• In terms of overall EMF exposure, all measured values were found to be below 4% of the limits set by the International Commission for Non-Ionizing Radiation Protection (ICNIRP).
• When base station power is equivalent, the exposure ratios were 5 to 10 dB below the limits, indicating a safe margin under normal operational conditions.

Conclusion

The findings underscore the importance of base station distribution and configuration in managing EMF exposure risks in indoor environments. The adherence to ICNIRP limits confirms that the current implementations of DMaMIMO base stations are within safe exposure levels, offering reassurances concerning public health implications of EMF from next-generation wireless technologies.