Wireless patient monitorization using full passive devices

Abstract

There is a strong motivation for the implementation of electronic identification systems and wireless sensors in hospitals. This work presents a sensor enabled passive RFID tag for patient monitorization. Special attention is paid to the analog FE, which has been designed and implemented in a low cost 0.35µm CMOS standard process. The proposed front-end architecture allows the implementation of power management techniques that, together with the power optimized blocks and the use of Schottky diodes in the voltage multiplier, achieves a long reading range. The fabricated analog front-end, assembled to a matched dipole antenna, is able to provide a wireless communication up to 2.4m from a 2W EIRP output power reader to a digital module+sensor with an average power consumption up to 37.5µW. The system has been tested with a temperature sensor. Successful ID and temperature communication with a commercial RFID reader over a distance of approximately 2m has been reported. The results demonstrate the capacity of the proposed system for wireless patient monitorization.