Design of multiband implantable loop antenna for in body applications

In this paper, a flexible loop implantable antenna is proposed for in body applications. The proposed antenna covers the Med Radio band (401-406MHZ) which is the standard band for Bio Implantable applications, ISM bands at 433-434.8MHz and 902-928MHz. The antenna is made of biocompatible loss free polyamide hollow cylindrical substrate of relative permittivity 3.5 having a size of 3.3 mm radius, height of 15 mm and thickness of 0.0254mm. The patch is wrapped over the cylindrical polyimide substrate. The simulated antenna is having two bands 272 - 458MHz resonates at 347 MHz and also covers bandwidth range 751 - 1015MHz having proper VSWR throughout the bandwidth. The Radiation pattern of this antenna is unidirectional having a gain of -32.15dB at 404.5MHz.