Wireless Telemetric Technique for Resistive Sensors in Biomedical Applications

The measurement of different quantities inside the human body has considerable difficulties due to various factors, including the characteristics of the environment itself, which may not allow the proper use of electronics or cabled connections between the inside and outside of the human body. The proposed solution is given by a passive telemetric system consisting of a passive sensor positioned within the human body and an external readout unit. In this paper, the passive sensor is a resistive sensor connected to an inductor, while the readout unit is connected to a second inductor positioned externally the measurement environment. No batteries are requested inside the human body, avoiding maintenance and risks for the subject. The proposed telemetric technique is based on a measurement of the impedance at the readout inductor's terminals and on a mathematical processing that extracts the sensor resistance value. Further experimental results are in progress.