Ultra-Low powered wireless sensors using RFID

This project details the design and development of a passive RFID-based smart sensing system, incorporating temperature, humidity, and motion sensors, that eliminates the reliance on batteries through ambient RF energy harvesting. The system leverages passive RFID technology to operate without an internal power source, addressing challenges in low-power embedded system design including sensor integration, serial communication protocol establishment, and energy management circuit optimization. A primary focus is on achieving stable operation under variable RF power availability and maximizing RFID tag performance within the 920-955 MHz band.

Key challenges tackled in this project include the selection and integration of ultra-low power sensors, establishing a robust serial communication link between sensors and the RFID chip, and developing an energy management system capable of efficiently harvesting and distributing RF energy. A software interface will be developed for data acquisition, processing, and graphical representation. Methodology includes PCB fabrication and the design of a user-friendly GUI/web interface for data visualization. The key achievement is the ability to wirelessly transmit sensor data upon interrogation of a passive RFID tag without external power consumption. Future work will explore integration of additional sensors to enhance system applicability in areas such as precision agriculture and human health monitoring.