WakeDroid: A Remote Boot Trigger for Android Devices as IoT Nodes

WakeDroid is an external power manager which can wake up "completely off-state" smartphones by remote control via a wireless link. Users just need to plug a WakeDroid USB dongle consisting of a rectifier and an antenna to the USB charging port of the smartphone. The WakeDroid USB converts input microwave signals into DC and charges up the internal capacitor. Then the energy is used to kick-start the smartphone. No hardware modification on the smartphone is required. Instead, we take advantage of the Android OS's battery charge management software that starts up automatically when connected to a charger. WakeDroid can boot smartphones within 35 m from a 0.48 W transmitter. WakeDroid drastically widens the activity area of smartphones by giving them "second life" as IoT nodes.