A 3-Transistor Low Power Rectifier for Wideband RF Energy Harvesting with a Threshold Voltage Compensation Technique using 45 nm Technology

Abstract

With the advent of modern wireless communication technology and increasing requirement of high speed network, network life-time is becoming a major area of concern. The need of network power management is gaining attention with the high data network in place and is making a paradigm shift towards green communication. Hence embedding the RF energy harvesting (EH) capability in a wireless network is becoming inevitable. To make RF EH a reality a high frequency rectifier is indeed indispensable along with other circuits in the system. The RF energy needs to be harvested from the available sources in the ambience. It is also seen that the current generation of RF sources radiates at a very low signal power. So, to successfully convert and store this energy, the rectifier must not only be able to provide a sufficiently higher percentage conversion ratio (PCE) but also be able to cater it at a lower range of signal power. This paper presents the design and analysis of a simplified 3-transistor high frequency rectifier. A threshold voltage compensation technique is also incorporated and it achieves a PCE upto 85% at -2dBm in its single stage implementation. This is observed to be one of the highest in-class efficiency as compared to recently reported designs. From the frequency response it is seen to exhibit wide band performance spanning almost all popular wireless bands. The dynamic power dissipation (DPD) is calculated to be 6.25pW at -2dB, whereas the leakage power (LP) is observed to be zero.