CALCULATION OF THE ELECTROMAGNETIC-FIELDS INDUCED IN THE HEAD OF AN OPERATOR OF A CORDLESS TELEPHONE

This paper shows the capability of the finite difference time domain ( FDTD) method to predict the interaction between the human body and the electromagnetic field generated by a cordless telephone. Both the inf luence of the human head on the performance of the cordless telephone and the energy deposited in the human head have been determined. The i nteraction has been evaluated for a simple dipole model and for an acc urate ''box'' model of the telephone. The FDTD method is a versatile m ethod for refining the antenna model. The results show that the use of the accurate box model in combination with a realistic model of the h ead derived from a nuclear magnetic resonance image is a prerequisite for accurate determination of the near fields induced in the head. The total amount of power absorbed in the head has been compared to the r adiated power. From our calculations we found that about 15% of the an tenna input power at 900 MHz is absorbed in the head.