Sensing With Wireless Power and Data Transfer—Design of a Multisensor Augmented RFID

The radio frequency identification (RFID) sensors featuring simultaneous wireless power and data transfer (WPDT) have provided promising potentials for flexible sensing and communication in future industrial applications. The performance of RFID sensors regarding the number of integrated sensors and interrogation distance is constrained by the efficiency of radio frequency energy harvesting (RF-EH) and the power management techniques for efficient power utilization. This investigation presents a design methodology for multisensor augmented RFID sensor focusing on the RF-EH efficiency, power management, and the system’s overall performance. The contributions include: 1) a multisensor augmented RFID design scheme to improve the efficiency of RF-EH and power utilization; 2) design of a planar inverted-F antenna (PIFA) and a differential feed Greinacher rectifier to improve the RF-EH efficiency; and 3) a power management optimization method to improve the power utilization efficiency based on the budgeting and analysis of the components’ consumption. A prototype system integrating temperature, humidity, and illuminance sensors is developed and experimentally verified. The presented techniques are proven a good reference for the research and practice of power-efficient sensing.