Dual band electrically small non-uniform pitch ellipsoidal helix antenna for cardiac pacemakers

A dual band electrically small folded ellipsoidal helix antenna (EHA) is designed for the wireless data communication and wireless power transferring functions of an artificial cardiac pacemaker. In this design, a spatially non-uniform pitch ellipsoidal helix structure is used to tune the dual resonant frequencies to the desired bands at 900 MHz and 2.4 GHz. Measurement on an wire antenna fabricated using selective laser sintering shows more than 10% relative bandwidth at each frequency band.