RF energy harvesting chip powered sensor node

Abstract

This work demonstrates a BLE compatible battery-less Wireless Sensor Mote, powered by an RF Energy Harvesting (RFEH) Chip. The chip integrates Energy Harvesting and Power conditioning circuits. RF-Energy is harvested from UHF RFID receiver (i.e, 865–868 MHz) and is stored in an external capacitor bank. This energy is utilized to run a microcontroller + radio SoC, wherein data from a sensor (analog temperature sensor) is read and broadcasted as BLE advertisement packets. An android app was developed to process and display the sensor value. The designed chip harvests at power level of −12 dBm and above. Whereas the complete system works at a power level of −8dbm. The maximum BLE packet transmission interval at the specified power level is about 30 minutes. To the best of our knowledge, this is the first work to demonstrate BLE broadcast with RF Harvesting.