Characterization of 3-D Loop Antenna to Overcome the Impact of Small Lateral Misalignment in Wirelessly Powered Intracranial Pressure Monitoring System

This communication presents a 3-D loop antenna to overcome the impact of small lateral misalignment of the order of 2 mm between the inductively coupled antennas. This communication is a continuation of our previously reported work. In our previous work, we have successfully activated the pressure monitoring sensor and performed the pressure readout for an intracranial pressure monitoring application. The pressure sensor was activated through wireless inductive near-field powering. Measurement showed that there was significant effect on pressure readout accuracy due to small lateral misalignment between the inductively coupled antennas. In this communication, we demonstrate that the structural properties of a simple 3-D loop antenna help to overcome the pressure readout error caused by small lateral misalignment. We present the design procedure, simulation results, and pressure readout measurement of the proposed 3-D loop antenna. Moreover, the pressure monitoring system shows maximum improvement of 9 mmHg in pressure readout accuracy with the proposed 3-D loop antenna.

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