A Mutually Decoupled Coil System to Improve Sensitivity of Inductively Coupled Communication

To improve the sensitivity of inductively coupled communication, a mutually decoupled transmitter and receiver coil (MDC) system are proposed in this paper. The proposed communication system is intended to be mounted on the frame of a spectacle and used to communicate through weak inductively coupling with an implant measuring intraocular pressure (IOP). The implant consists of a coil that resonates with a capacitor. The capacitance of this capacitor is designed to change with the IOP, thus leading to a change in the self-resonant frequency of the implant. The transmitter coils excites the implant, while the decoupled receiver coil continuously monitors the self-resonant frequency of the implant. The induced voltage across the receiver coil is used to determine the IOP. Simulation results show that a 1.43% change in the sensor capacitance leads to a one mV change in the voltage induced across the receiver coil.