A 925 MHz 1.4μW wireless energy-harvesting circuit with error-correction ASK demodulation for RFID healthcare system

This paper presents a low-power energy-harvesting circuit with error-correction demodulation for radio-frequency identification (RFID) application. This circuit uses the new structure to demodulate ASK signals and includes the power unit with a wake-up circuit and a power-on-reset controller. The energy-harvesting circuit proposed by this paper can substantially decrease the capacitance used in the demodulator circuit and the wake-up circuit, and the capacitance is 14 pF only. Moreover, a detection circuit and a correcting circuit are adopted to enhance bit error rate of decoding. The chip was implemented in CMOS 0.18 μm technology. The sensitivity of this work is -13 dBm. The pulse width error can be reduced to less than 1% to fit the EPC Gen-2 standard by error-correction demodulator.