SAR compliance assessment of PMR 446 and FRS walkie-talkies.
The vast amount of studies on radiofrequency dosimetry deal with exposure due to mobile devices and base station antennas for cellular communication systems. This study investigates compliance of walkie-talkies to exposure guidelines established by the International Commission on Non-Ionizing Radiation Protection and the Federal Communications Committee. The generic walkie-talkie consisted of a helical antenna and a ground plane and was derived by reverse engineering of a commercial walkie-talkie. Measured and simulated values of antenna characteristics and electromagnetic near fields of the generic walkie-talkie were within 2% and 8%, respectively. We also validated normalized electromagnetic near fields of the generic walkie-talkie against a commercial device and observed a very good agreement (deviation <6%). We showed that peak localized specific absorption rate (SAR) induced in the oval flat phantom by the generic walkie-talkie is in agreement with four commercial devices if input power of the generic walkie-talkie is rescaled based on magnetic near field. Finally, we found that SAR of commercial devices is within current SAR limits for general public exposure for a worst-case duty cycle of 100%, that is, about 3 times and 6 times lower than the limit on the 1 g SAR (1.6 W/kg) and 10 g SAR (2 W/kg), respectively. But, an effective radiated power as specified by the Private Mobile Radio at 446 MHz (PMR 446) radio standard can cause localized SAR exceeding SAR limits for 1 g of tissue.
Department of Information Technology, iMinds/UGent, Ghent, Belgium.
Günter
G
Vermeeren
Department of Information Technology, iMinds/UGent, Ghent, Belgium.
Wout
W
Joseph
Department of Information Technology, iMinds/UGent, Ghent, Belgium.
Luc
L
Martens
D003198:Computer Simulation; D003257:Consumer Product Safety; D004867:Equipment Design; D004869:Equipment Safety; D011845:Radio / Q000592:standards*; D011846:Radio Waves; D059015:Wireless Technology / Q000295:instrumentation / Q000592:standards*
absorption assessment; exposure; helical antenna; modeling; two-way radio transceiver