Wireless and batteryless blood pressure sensor

A low-power invasive blood pressure transducer has been designed. It is based on a structure of four high resistive strain gauges in a full Wheatstone bridge configuration. For obtaining the required sensitivity, the gauge was allocated performing a careful mechanical simulation of the membrane behaviour. The electronic conditioning circuit and the ADC were optimized to compensate the noise introduced by the high resistive gauges. A batteryless RFID tag designed to incorporate and to supply the sensor was fabricated and measured. It power supplies the sensor at a distance longer than 50 cm from a standard reader, while the reported ranges -to the best of our knowledge- are shorter than 10 cm. This wireless and batteryless sensor is especially suitable for surgery rooms and intensive care units.