A Dual-Band Wide-Input-Range Adaptive CMOS RF–DC Converter for Ambient RF Energy Harvesting

Abstract

In this paper, a dual-band wide-input-range adaptive radio frequency-to-direct current (RF–DC) converter operating in the 0.9 GHz and 2.4 GHz bands is proposed for ambient RF energy harvesting. The proposed dual-band RF–DC converter adopts a dual-band impedance-matching network to harvest RF energy from multiple frequency bands. To solve the problem consisting in the great degradation of the power conversion efficiency (PCE) of a multi-band rectifier according to the RF input power range because the available RF input power range is different according to the frequency band, the proposed dual-band RF rectifier adopts an adaptive configuration that changes the operation mode so that the number of stages is optimized. Since the optimum peak PCE can be obtained according to the RF input power, the PCE can be increased over a wide RF input power range of multiple bands. When dual-band RF input powers of 0.9 GHz and 2.4 GHz were applied, a peak PCE of 67.1% at an input power of −12 dBm and a peak PCE of 62.9% at an input power of −19 dBm were achieved. The input sensitivity to obtain an output voltage of 1 V was −17 dBm, and the RF input power range with a PCE greater than 20% was 21 dB. The proposed design achieved the highest peak PCE and the widest RF input power range compared with previously reported CMOS multi-band rectifiers.

A 900 MHz, Wide-Input Range, High-Efficiency, Differential CMOS Rectifier for Ambient Wireless Powering

“…It has a compact and small silicon area of 0.0093 mm 2 . In addition, it has a better sensitivity and dynamic range than the voltagethreshold-compensated, DM nested, and adaptive rectifiers [ 12 , 13 , 14 ]. Compared to the low power performance, the proposed design offers the best peak PCE at −35 dBm of 25.5%.…”

“…However, the proposed design increases the circuit complexity and parasitic elements, which degrades the performance of the rectifier at the UHF. The adaptive RF-DC converter is introduced to cover a wide input RF power range in [ 14 ], which varies the number of stages depending on the input power; however, the proposed design still has a limited dynamic range due to the reverse leakage power.…”

High-Performance Multiband Ambient RF Energy Harvesting Front-End System for Sustainable IoT Applications—A Review

“…A low-loss CMOS multiband RFEH system is realized through the narrowband approach [70], [124], [125], [126], [127], [128], [129], [130], [131], [132], [133], [134]. The narrowband impedance matching network focuses on creating a one-to-one matching scenario.…”

“…However, on-chip impedance matching network suffers from low Q-factor for the inductor and capacitor due to high losses in the substrate [135]. To address this issue, several work in employing off-chip inductor and capacitor are proposed [70], [127], [128], [129], [130], [131], [132], [133], [134]. Reference [127] proposed a novel impedance matching network with a 1:100 transformer and a single LC matching network.…”

A Fully-Integrated Ambient RF Energy Harvesting System with 423-μW Output Power

“…Various multi-channel, multi-band RFEH systems adopting discrete elements require off-chip components [1,4,10,[17][18][19][20], which include Schottky diodes [15] and rectenna [21]. Figure 1 presents the simple block diagram of the proposed RFEH system, which includes an on-chip impedance matching network (IMN), a stacked rectifier, and a chargepump-based DC-to-DC converter with the developed shared-auxiliary-biasing ring-voltage-controlled-oscillator (SAB-RVCO).…”