A miniature implantable microstrip antenna design for dual-band biotelemetry operations

In this study, an implantable microstrip sandwiched (IMS) antenna for dual-band biotelemetry communication is proposed. The proposed antenna is comprised of a spiral shaped radiating element and a bended microstrip line sections. The radiating element is sandwiched between two thin substrates backed by a rectangular ground plane (GP). In addition, a shorting pin (SP) which connects radiating element to GP is used for miniaturization purpose. By optimizing the proposed antenna in terms of its size, feeding and SP position, the IMS antenna with only 10.6x10x1.27 mm³ offers a dual band performance (VSWR<2) covering medical implant communication services (MICS) 402{405 MHz) and industrial, scientific and medical (ISM) 2.4{2.48 GHz) bands. It is numerically demonstrated that the proposed implant antenna offers 50% and 29% impedance bandwidth at the designated ISM and MICS frequency bands respectively. In the paper, numerical results for the proposed design are presented.