Human Presence Detection and Energy Harvesting Using SWIPT

This paper presents an innovative architecture for human presence detection within the Simultaneous Wireless Information and Power Transfer (SWIPT) framework, enabling seamless energy harvesting alongside human body detection. Two architectural designs are outlined: Design 1 leverages the PowerCast concept for energy harvesting, albeit with specific limitations, while Design 2 focuses on enhancing capacitor charging voltage at similar distances. Both designs feature an always-on microcontroller that transitions from sleep mode to transmit data upon detecting a person, subsequently returning to sleep mode. Design 2 is particularly suited for longer distance sensing. The booster, a pivotal component, establishes a constant output voltage, enabling connected capacitors to charge steadily without impeding the open-circuit voltage of the input circuit. Through comprehensive testing, the SWIPT-based sensor demonstrates the ability to differentiate between various walking speeds (slow, normal, fast) by analyzing signal drop times in the central processor.