Miniaturized Broadband Antenna for Implantable Biomedical Devices

ABSTRACT A miniaturized broadband antenna for implantable biomedical devices is proposed, operating at the Industrial, Scientific and Medical(ISM) 2.45 GHz band. By employing slots and short‐pins, a compact size of 0.026λ × (0.025λ) 2 × 0.021λ is realized, which is the smallest radius among circular patch antennas currently. Meanwhile, the multimode resonance method is utilized to help achieve bandwidth expansion. Furthermore, compared with circular patch antennas of the same radius, the relative bandwidth of this antenna is up to 55.87%, ranging from 2.18 to 3.87 GHz. To verify the performance of the antenna, the fabricated prototype is placed in pork and its bandwidth is measured to be 1.02 GHz.