A 19-μW Blocker-Tolerant Wake-Up Receiver With −90–dBm Energy-Enhanced Sensitivity

Abstract

A 915-MHz energy-enhanced wake-up receiver (EE WuRx) is proposed for wireless energy-harvesting (WEH) systems based on a modified legacy device. With the presented frequency-hopping two-tone modulation (FH TTM), the receiver converts the in-band harvesting energy (HE) from the legacy device into the data power with reduced constraint to the HE frequency. Fabricated in a 65-nm CMOS process, the proposed wake-up receiver (WuRx) achieves a <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 90-dBm EE sensitivity when receiving a continue-wave (CW) energy of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 25 dBm and gives a sensitivity improvement of 26.4 dB compared with the case without HE, while consuming 19 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\mu$</tex-math> </inline-formula> W at a 5-kb/s data rate. Upon the <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$-$</tex-math> </inline-formula> 90-dBm EE sensitivity, the WuRx performs 46.5-and 22-dB tolerances to a 100-kb/s amplitude-modulated (AM) blocker and an 8-MS/s quadrature-AM blocker, respectively.