Improved performance of highly compact CP implantable antenna using slots.

A highly miniaturized miniaturised meander-shaped implantable antenna is proposed for biomedical applications. The antenna has a volume of 12.29 mm3 and is designed with slots only. Using only slots on patch and ground surface, the fabrication of proposed implantable antenna is quite effortless unlike using techniques of sorting pin, metamaterial, and multiple patch stacking. The analysis shows that the proposed antenna has excellent impedance bandwidth of 140 MHz (2.39 GHz to 2.53 GHz) with resonating frequency of 2.41 GHz, circular polarisation with an axial ratio bandwidth of 80 MHz (2.45 GHz to 2.53 GHz), gain of −23.45 dB, acceptable SAR 901 W/KG in industrial, science and medical band (ISM). The detail parametric study of the designed antenna with substrate/superstrate materials, different human body tissues, different depth of penetration in human tissues, and thickness of substrate/superstrate have been analysed successfully. For the authenticity purpose, the results are correlated with the prepared skin mimicking gel (saline solution) in vitro model. The fabricated antenna indicates similar performance as provided by the proposed simulated antenna design. [ABSTRACT FROM AUTHOR]