Study on the interactions between electromagnetic fields and biological tissue at high frequency band is an important aspect in the area of wireless communications. The use of millimeterwave frequency band for fifth Generation (5G) devises involves new challenges in terms of Radio Frequency Electromagnetic Field Exposure (RF-EMF) limits and compliance assessment since the basic restrictions for limiting human exposure change from the Specific Absorption Rate (SAR) to the power density. The Electromagnetic Field Exposure to the human head has been studied based on power density by means of numerical simulation for the frequency band of 10 GHz. Study on radio frequency energy absorption has been done based on radiation from a printed monopole antenna at frequency of 10 GHz, transmitting directly towards the human head tissue model. Human head model is constructed from magnetic resonance images with frequency dependent tissue electrical properties. It is shown that at millimeter wave frequency, i.e. 10 GHz, with realistic source (20 mW) and head-source separation distance (10 mm), the amount of power density is in the range of regulatory limits and requirements on EMF exposure. The obtained results might provide valuable information for the design of 5G handheld devices and EMF compliance assessment.
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