An ultra low-power wakeup receiver for energy-efficient wireless senor network

An ISM band sub-100μW Wake-Up Receiver (WuRx) has been presented in this study. Issues regarding tradeoffs between system architectures for Ultra-Low Power (ULP) WuRx are analyzed and compared. Push-Pull Current Re-Use (PPCRU) topology with programmable bias-controlled technique has been proposed for maximum conversion gain requirement for minimum power consumption. The chip of WuRx is 0.79 mm in size and has been implemented in a 0.18-μm CMOS technology. Measurement shows this technique increases conversion gain by 4.8 dB without extra core current consumption which comes the result of 3.7 dB figure-of-merit (FOM) improvement. Minimum power consumption of WuRx is 88.8 μW from 1.2-V supply. When operating at 100 kbps data rate, the sensitivity is -63 dBm (10^-3 BER) with 888-pJ/b energy consumption. Owing to gain improvement function in RF front end, the optimum FOM of -183.4 dB can be achieved. Therefore, the proposed gain-improved technique fulfills optimum system performance between power consumption and conversion gain requirement.