무선 클럭 하베스터와 RF 에너지 하베스터 집적 회로 설계
Design of Wireless Clock Harvester and RF Energy Harvester Integrated Circuit
초록/요약
In this paper, we propose an energy efficient wireless clock harvester and a dual band RF energy harvester with high efficiency over a wide input power range for IoT wireless sensors. Energy efficient wireless clock harvester based injection locked ring oscillator (ILRO) is proposed to generate a 450 MHz clock from a harvested 900 MHz RF signal for RF energy harvesting IoT sensor applications. By optimizing the width of the injection transistor, the locking range is optimized in the ultra-low power consumption operation. Also, the bias voltage of the PMOS current source is optimized to lower the minimum RF input power for locking at 450 MHz output frequency for ambient RF clock harvesting. The cir-cuit is designed in a 65 nm CMOS process, achieves a 23.8 % locking range at -15 dBm input power, and outputs a stable 450 MHz clock at a minimum input pow-er of -34 dBm. The power consumption is 2.03 µW, which is very low for opera-tion with RF energy harvesting. The proposed dual band RF energy harvester is designed with 0.18μm CMOS process. To improve power conversion efficiency, the rectifier circuit is designed using thick oxide MOSFETs, and has adaptive operation to maintain high effi-ciency over a wide input power range. The RF energy harvester can also operate in both single-band and dual-band operation at 0.9 GHz and 2.4 GHz. As a result, a maximum efficiency of 66.7% at -19 dBm and 61.5% at -13 dBm was achieved. It has an input sensitivity of -17 dBm and maintains more than 20% PCE over an input power range of 21 dB.
more목차
Abstract i
Table of Contents iii
List of Figures v
List of Tables viii
Chapter 1. Introduction 1
1.1. Energy harvesting for IoT wireless sensor 1
1.2. Wireless clock harvester 3
1.3. RF energy harvester 4
Chapter 2. Proposed energy efficient wireless clock harvester 5
2.1. Circuit design 5
2.1.1. Optimization of locking range 7
2.1.2. Optimization of the input sensitivity 11
2.2. Simulation results 14
Chapter 3. Proposed dual-band RF energy harvester 20
3.1. Adaptive rectifier design 20
3.2. Matching network de-sign 23
3.3. Simulation re-sults 26
Chapter 4. Conclusion and future work 35
Publications 36
References 37
국문요약 41
