A 136μW Over 800m Range Backscatter-Like UHF Band Transceiver

Backscatter transceivers are often used in ultra-low-power Internet of Things (IoT) applications. However traditional backscatter transceiver (TRX) cannot actively control the transmitted power, which greatly limits the communication distance. This paper introduces a novel backscatter TRX operating in the ultra-high frequency (UHF) band, with a low power consumption of only 136μW and an impressive communication range surpassing 800 meters. Unlike the backscatter, the received continuous wave (CW) is not reflected via impedance modulating at the antenna but is directed into the TRX to be modulated and amplified. This technique significantly extends the communication range at a low power consumption. A coupler serves to prevent the direct entry of transmitted signals into the receiving path, ensuring the received CW remains unaffected to be modulated. Implemented in TSMC 40nm CMOS, the proposed TRX core occupies 0.7 mm
²
and works under a 0.7V supply voltage with the -54.6dBm input power and -20dBm output power.