Study on electromagnetic protection of hand-held transceivers

This paper studies how to reduce electromagnetic radiation of hand-held transceivers to humans with shielding theory, and how this method effects the far-field characteristics which reflects the communication performance. It calculates and analyzes near-field electromagnetic protection of transceivers by four shielding cases with the finite difference time domain software system developed by authors, and far-field characteristics of the two cases. It shows that the effects of near-field electromagnetic protection will be better when the shielding plane is bigger or it connects with the RF/logic plane, and that the effect is obtained at the cost of the far-field characteristics; the maximum of the electric field decreases 3.33 dB and 4.27 dB respectively, the electric field decreases 2.92 dB and 8.45 dB respectively at the position of the ear correspondingly.