On the geometry, impedance matching and quality factor of implantable planar dipole antennas

Design and performance of implantable planar dipole antennas from a) current phase and metallization, b) impedance matching, and c) quality factor point of view are discussed here. Antennas are built for wireless biotelemetry applications in the Medical Implant Communications Service (MICS) frequency band (402-405 MHz). As shown, implementing detailed analysis with emphasis on current phase, significant miniaturization can be achieved. Also, impedance matching with lumped elements proves to be inferior to the use of metallization. Further, the quality factor of two planar dipole antennas is assessed using exact and approximate expressions. As demonstrated, deep knowledge of design techniques is important for obtaining an optimum miniature antenna.