Impedance

On-chip implantable antennas for wireless power and data transfer in a glaucoma monitoring SoC

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Loïc Marnat, et al., "On-chip implantable antennas for wireless power and data transfer in a glaucoma monitoring SoC" IEEE Antennas and Wireless Propagation Letters (11), 2012, 1671. Abstract: For the first time, separate transmit and receive on-chip antennas have been designed in an eye environment for implantable intraocular pressure monitoring application. The miniaturized antennas fit on a 1.4-mm 3 CMOS (0.18 μm) chip with the rest of the circuitry. A 5.2-GHz novel inductive-fed and loaded receive monopole antenna is used for wirelessly powering the chip and is conjugately matched to the

Impedance matching through a single passive fractional element

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Ahmed Radwan, et al., "Impedance matching through a single passive fractional element." In Proceedings of the 2012 IEEE International Symposium on Antennas and Propagation, 2012, 1. For the first time, a generalized admittance Smith chart theory is introduced to represent fractional order circuit elements. The principles of fractional order matching circuits are described. We show that for fractional order α ; 1, a single parallel fractional element can match a wider range of load impedances as compared to its series counterpart. Several matching examples demonstrate the versatility of

5.2-GHz RF Power Harvesting Module in 0.18 μm CMOS for Biomedical Implantable Sensors

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Mahmoud H. Ouda, et al., "5.2-GHz RF Power Harvesting Module in 0.18 μm CMOS for Biomedical Implantable Sensors" IEEE Transactions on Microwave Theory and Techniques 61, (5), 2013, 2177. Abstract: A first fully integrated 5.2-GHz CMOS-based RF power harvester with an on-chip antenna is presented in this paper. The design is optimized for sensors implanted inside the eye to wirelessly monitor the intraocular pressure of glaucoma patients. It includes a five-stage RF rectifier with an on-chip antenna, a dc voltage limiter, two voltage sensors, a low dropout voltage regulator, and MOSCAP based on