MEMS Energy Harvesting Powered Wireless Biometric Sensor

Abstract

One of the main challenges in developing wireless biometric sensors is the requirement for integration of various systems into a very compact device. Such systems include sensing units, conditioning electronics, transmitters and power supplies. In this work, a novel system integration architecture is presented. A unique feature of this new architecture is that the sub-systems are selected and designed for direct output-to-input connection. An array of active pH sensors is used to transform a pH level to an electrical potential in the range of 0 - 2 Volts. This signal is amplified by an electrostatic energy harvester suitable for human motion operation. The amplified signal drives a custom LC transmitter specially designed to suit the harvester output. A system of notable simplicity is achieved and may serve as a demonstrator for other wireless sensors.