On the human exposure to radio frequency radiations expected from future small connected objects

Abstract

This paper investigates the human exposure to radio frequency radiations expected from future connected objects. The paper focuses on small objects of around ten centimeters. The study takes into account very recent advances on the design of compact antenna arrays. The specificities of the physical layer of wireless communication standards such as Orthogonal Frequency Division Multiplex waveform and Multiple Input Multiple Output techniques are also taken into account. The Specific Absorption Rate is measured for an object using time reversal based spatial focusing (or equivalently Maximum Ratio Transmission beamforming) as a multi-antenna technique and 8 port micro-structured antennas or 8 port patch antennas as compact antenna solutions.