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In this study, an ultraminiaturized implantable antenna is developed for biotelemetry applications. It has triple-band characteristics in the industrial, scientific, and medical (ISM) bands of 902–928 MHz for data telemetry and 2400–2483.5 MHz for power-saving applications and midfield band (1824–1980 MHz) for wireless power transfer simultaneously. The size of the proposed antenna is 0.068 $\lambda _{g}\,\,\times0.048\,\,\lambda _{g}\,\,\times0.0036\,\,\lambda _{g}$ and it is the smallest size of any triple-band implantable antenna ever devised without using shortening vias. Such a compact size is achieved by meandering the shape of the radiating patch and adding open-ended ground slots. Unlike most miniaturized implantable antennas reported in the available literature, no shortening pin is used and this makes the fabrication of the antenna very easy. The bandwidths measured in minced pork muscles are 14% and 24% in the lower and upper ISM bands, respectively, and 12% in the midfield band. The maximum values of the realized gain of the proposed antenna obtained in the heterogeneous skin phantom at 915, 1900, and 2450 MHz are −27.2, −22.2, and −19.9 dBi, respectively. In addition, specific absorption rates (SARs) in the heterogeneous skin and muscle tissues at the three resonance frequencies are calculated and show compliance with the IEEE standards for ensuring human safety. Finally, the range of the biotelemetry link is evaluated by calculating the wireless communication link budget at data rates of 7 kb/s, 100 kb/s, and 10 Mb/s at resonance frequencies. [ABSTRACT FROM AUTHOR]

An intraoral tongue drive system (iTDS) is an assistive technology that enables paralyzed people to improve their lifestyle by allowing them to navigate their wheelchairs and access computers using tongue gestures. In this paper, we present two dual-band antennas: a meandered dipole antenna and a meandered planar inverted-F antenna (PIFA). We designed the proposed antennas to operate at industrial, scientific, and medical (ISM) bands 433 and 915 MHz to mitigate the external interference issue, which can severely affect frequency bands. Our proposed antenna footprints are $17.25 \times 8 \times 0.635$ mm3 and $42\times 10 \times 0.635$ mm3 for the PIFA and dipole antenna, respectively. Initially, we designed and analyzed the proposed antennas in multilayer mouth models. The performances of the antennas were validated in a realistic human head phantom. We analyzed the performances of the antennas in terms of the reflection coefficient, gain, efficiency, bandwidth, and link budget for wireless communication in four scenarios. Additionally, to address safety concerns, we calculated the specific absorption rates (SARs) for both antennas and found them to be safe according to the IEEE C95.1.2005 guideline. Finally, we measured the reflection coefficient in the more realistic environment of a 26 year-old subject’s mouth. The radiation pattern was measured in a 3-D head model and minced pork muscle, which approximated the open and closed mouth scenarios, respectively. The measurement results were in reasonable agreement with the simulation results. [ABSTRACT FROM AUTHOR]