Development of zero-energy communication sensor tag system using ambient Wi-Fi signal

We propose and design a zero-energy wireless communication sensor tag system using Wi-Fi (802.11a/b/g/n) signal. The proposed method doesn't spend energy in communication because of using modulation the reflected Wi-Fi signal's power from the tag. The tag is possible to be operated without battery because of generating power from Wi-Fi signal. We present a communication sequence for a downlink and an uplink of data between the sensor tag and Wi-Fi device/Wi-Fi AP infrastructure. This system can provide the identification and sensor data of tag on the internet connectivity without needing the wireless communication infrastructure like an additional router. Wi-Fi device like mobile terminal reads the sensor data by detecting the level of the power modulated Wi-Fi packet. This system can be achieved wireless connectivity for batteryless IoT device.