BANDWIDTH ENHANCEMENT AND SIZE REDUCTION OF AN IMPLANTABLE PIFA ANTENNA FOR BIOTELEMETRY DEVICES

By means of embedding hook-shaped slots at the edges of the radiating patches for a stacked planar inverted-F antenna (PIFA), functions of bandwidth enhancement and size reduction can be achieved for suitable use in implantable biotelelmetry devices. The designed antenna with overall size of only 8 X 8 X 8 X 1.9 mm(3) provides a monopole-like realization pattern, a radiation efficiency of 0.55%, and a wide 10 dB impedance bandwidth of 122 MHz covering the 402-405 MHz medical-implant-communication-service (MICS) frequency band. Comparing with the reported most compact antennas, the proposed design obtains not only 144% wider bandwidth but also 36% more compact structure size. (C) 2009 Wiley Periodicals Inc. Microwave Opt Technol Lett 51: 755-757, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24142