Non-stationary statistics with amplitude probability density function for exposure and energy density reporting near a mobile phone running 4G applications

Abstract

Present contribution introduces, for the first time, the description of human exposure dynamics to mobile phone radiation by implementing the use of in-air integrated energy density (IED) evolution in time. Using the amplitude probability density (APD) function capability of a real-time spectrum analyzer, we demonstrate the differences in exposure due to five different mobile applications running in Long Term Evolution (LTE) standard, based on energy deposited in air: voice call; voice over LTE (VoLTE); video call, file download and live streaming. This exposimetric method will be of great interest also for the new 5G communication standard. The superiority of the approach has three branches: a) integrated APD allows a sample rate of the order of 0.6 × 108/s which is equivalent to an extremely agile tracing of the power level change in LTE communication standard (happening at every 6.67 µs); b) momentary and mean IED accumulation rate can be computed, and minute differences between mobile applications may be observed during their running time; c) the superficial tissue temperature increase may be rapidly estimated after the period of use of one specific wireless application in the GHz frequency range. The method implemented here also provides the means for rapid usage profile expectancy assessment of a mobile phone user.