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.