Towards Ultra-Low Power Transceivers for Pico-IoT

This article provides a comprehensive review of ultra-low power receivers for Pico-IoT applications. The application scenarios and specification requirements of the receivers used in IoT systems are introduced. In addition, the evolution of the receiver's architecture and the key techniques are presented in the article. The advantages of different topologies are analyzed. Specifically, the receiver based on micro-electromechanical systems (MEMS) are presented. The challenges and bottleneck of the receivers for pico-IoT are illustrated. This article aims to reveal the significance and future trends of the ultra-low power transceivers. In addition, a low-power and high sensitivity wake up receiver (WuRX) working in ISM band is designed and fabricated in this work. A high-Q MEMS resonator is employed to improve the selectivity and interference rejection. The MEMS is co-designed with the low noise amplifier (LNA) for resonant noise matching (RNM) technique which provides passive gain to reduce the input-referred noise of the receiver. Furthermore, an energy super-regenerative (ESR) receiver is proposed which reduced the power consumption through replacing the power-hungry oscillator in traditional super-regenerative receiver with an ESR loop. The proposed MEMS-based receiver is implemented in a TSMC 65nm CMOS technology. The measurement results show that the receiver achieves -70dBm sensitivity at 10-3 BER while consuming only 2.83 µW power consumption at 1-V power supply. In addition, -20-dB SIR is obtained at 2-MHz offset from the center frequency.