The Effect of Miniaturized Circular Antennas on the SAR Reduction for Wireless Applications

This work, presents the design and realization of two new miniaturized circular antennas as well as their effects on the human body. The first step consists in simulation each bi-band antenna at 2.5 GHz and at 5.2 GHz for wireless applications using the simulators HFSS and CST Microwave studio. The second step is manifested by the type of permeability substrates, the modifications of the radiating element and the ground plane as well as the modification of the feeding technique. All these miniaturization methods were used to limit the peak of specific absorption rate (SAR) in the human body. The SAR is calculated on a 1 and 10 g tissue mass respectively. The performed tests show that the SAR rate, which affects the human body tissues and obtained by the antenna with a full ground plane, is lower than that provided by the antenna with a truncated ground plane. Furthermore, the SAR rate observed in the different frequency bands for the antenna 2 complies with the standards proposed by the international commission on non-ionizing radiation protection.