A System for Wireless Power Transfer and Data Communication of Long-Term Bio-Monitoring

A system for wireless power transfer and data communication of implantable bio-monitoring systems is presented. The proposed solution uses a servo-controlled power transmitter moved under the animal moving space. An x-y movable magnetic coil transmits the required power with a level able to keep constant the received energy by the bio-sensor system. The power is transferred via the optimized remote powering link at 13.56 MHz. The received ac signal is converted to dc voltage with a passive full-wave integrated rectifier and the voltage regulator supplies 1.8 V for the implantable sensor system. The sensor control and readout circuit measures the current on the bio-sensors and transmit the data to the transmitter. The sensor data are transmitted to an external reader by a low-power OOK transmitter and received by a custom designed receiver at 869 MHz. The results are shown in a tablet computer in real time continuously. The long-term characterization of the implantable system is verified by a fully bio-compatible packaged implant with 30 days measurement. A complete prototype is also presented to prove the overall system performance with the experimental in vitro measurement.