A matched RF charger for wireless RF power harvesting system

Abstract

In this article, special type of RF Charger is proposed for Wireless RF power harvesting system. RF charger is consisted of impedance matching circuit, full bridge CMOS rectifier, active diode, hysteresis switch, and DC–DC booster. The proposed RF charger is to obtain maximum available RF power through adjusting impedance matching circuitries. The proposed RF charger is matched to Korean WCDMA frequency band from 1960 to 1980 MHz. The minimum input RF power for charging 5 V battery is −10 dBm. The RF to DC conversion efficiency of the RF charger is 81% at 30 mA load current with 5 V battery, and the maximum output voltage is 5.5 V. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:1622–1625, 2015

RF power harvesting: a review on designing methodologies and applications

“…Applying RF energy to recharge the batteries is one approach to enhance the lifespan of WSNs [83,84]. Lee et al [85] is an example of an RF charger utilizing WPH technology. The system was able to work with a minimum input power of −10 dBm (0.1 mW) in the frequency range from 1.96 to 1.98 GHz to charge a 5 V super-capacitor.…”

A CMOS voltage-controlled oscillator using a cascode structure

“…Given that the VCO generates a carrier signal in RF systems, the performance of the VCO affects the overall performance of the RF system. Considering the recent rapid development of wireless communications for the Internet of Things (IoT), RF integrated circuits (ICs) with lower power consumption have received considerable amounts of attention [6][7][8]. More recently, many studies related to the CMOS VCO have been conducted in an effort to improve its power consumption and phase noise [9][10][11].…”

“…In recent years, extensive research work has been carried out in the design of broadband microwave components and systems. UWB power splitters are being studied and researched extensively [1][2][3][4][5][6][7][8][9].…”

“…Modern electronic warefare systems, wide band radars, and impulse radio require broadband power splitters. Several researchers had reported various circuit structures in literature [1][2][3][4][5][6][7][8][9] to realize power splitters with wide and broad operating bandwidth. Broadband power splitters have been conventionally realized using Lange couplers and multistage Wilkinson splitters [1][2][3].…”

“…Although Lange coupler is broadband in nature, the critical issue is the bonding between alternate arms of couplers which limits the frequency of operation. On the other hand, multistage power splitters connected in series are easy to design, but these are lengthy and occupy more space [4][5][6][7][8][9]. However, amplitude ripples were observed in the transmission co-efficient.…”