Determinants of exposure to electromagnetic fields from mobile phones

In actual conditions of use, the power radiated from cellular phones changes during conversation depending on several factors. Upon request from the radio base station (RBS), the phone in fact, reduces, its power to a level that is deemed optimum for the quality of conversation. In this study, special phones, which had been modified to allow the continuous logging of power emitted during the calls have been used. Off-line processing of recorded data allowed the analysis of the behaviour of mobile phones under real-use conditions. Further data recorded by operators at selected base stations were used for the purposes of comparison and checking of the effectiveness of the experimental method. The results indicate a high proportion of use of the highest power levels, under any circumstance. Such behaviour is mainly due to frequent handovers requested by the control software to optimise the communication traffic.