Numerical assessment of EMF exposure for small-cell indoor radio base stations

Sammanfattning

Specific absorption rate (SAR) tests for complex devices, such as radio base stations (RBS) equipped with multiple-input multiple-output (MIMO) antenna systems, is significantly time-consuming, due to a large amount of cases that needs to be considered. The test cases must consider various distances, frequencies, different phase combinations of MIMO antennas, device positions, etc., leading to a large burden and long time laboratory occupations. To address this concern, the thesis explores numerical methods to improve the efficiency and practicality of SAR assessment by using full wave electromagnetic simulations for a small-cell indoor RBS. The simulated results are validated through measurements to check the accuracy and reliability of using numerical methods. Additional studies are also carried out to simplify simulation models aimed at reducing the computational loads and time. This work shows that the simulation results match the measured data for most of the studied cases, confirming that numerical methods can be reliably used to evaluate SAR for complex devices, such as an indoor MIMO RBS. The discussions and results provided in the thesis contributes to the broader goal for rapid deployment of next-generation wireless devices by providing an alternative simulation-based approach for EMF exposure testing compared to measurement-based testing. By using the alternative suggested method, i.e., simulation based approach, it would reduce the reliance on time-consuming and costly measurement procedures.