Autonomous RFID sensor platform with highly efficient energy harvesting circuit

An autonomous RFID sensor platform is designed and implemented using off-the-shelf discrete components. It includes a dipole antenna to wirelessly transmit the stored data to a reader according to the EPCglobal Class-1 Gen2 standard. The rectifier operates with received power as low as -10dBm. The microcontroller dissipates below 500nW in sleep mode, allowing an optimal energy harvesting and storage from the RF source. The input impedance is dynamically adapted to respond over a range of input power and loads. The collected power is used to write the data captured by sensors into the user memory of an RFID tag at a user selectable rate. The results demonstrate the feature of the system to perform operations up to a distance of 1.5 m from an RF energy source of 30dbm, thus it is a suitable candidate for use in passively powered sensor networks.