Research Article Compact and High-Efficiency Rectenna for Wireless Power-Harvesting Applications Dalia H. Sadek , 1 Heba A. Shawkey , 2 and Abdelhalim A. Zekry 1 1 Faculty of Engineering, Ain Shams University, Cairo, Egypt 2 Electronics Research Institute (ERI), Giza, Egypt Correspondence should be addressed to Dalia H. Sadek; doly_sadek@hotmail.com Received 6 October 2021; Accepted 6 December 2021; Published 15 December 2021 Academic Editor: Gino Sorbello Copyright©2021DaliaH.Sadeketal.isisanopenaccessarticledistributedundertheCreativeCommonsAttributionLicense, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. A compact, single-layer microstrip rectenna for dedicated far-ﬁeld RF wireless power-harvesting applications is presented. e proposed rectenna circuit conﬁgurations including multiband triple L-Arms patch antenna with diamond slot ground are designed to resonate at 10, 13, 17, and 26 GHz with 10 dB impedance bandwidths of 0.67, 0.8, 2.45, and 4.3 GHz, respectively. Two rectiﬁer designs have been fabricated and compared, a half wave rectiﬁer with a shunted Schottky diode and a voltage doubler rectiﬁer. e measured and simulated maximum conversion eﬃciencies of the rectiﬁer using the shunted diode half-wave rectiﬁer are 41%, and 34%, respectively, for 300 Ω load resistance, whereas they amount to 50% and 43%, respectively, for voltage doubler rectiﬁer with 650 Ω load resistance. Compared to the shunted rectiﬁer circuit, it is signiﬁcant to note that the voltage doubler rectiﬁer circuit has higher eﬃciency. Both rectiﬁer’s circuits presented are tuned for a center frequency of 10GHz and implemented using 0.81mm thick Rogers (RO4003c) substrate. e overall size of the antenna is 16.5 × 16.5mm 2 , and the shunted rectiﬁer is only 13.3 × 8.2mm 2 and 19.7 × 7.4 mm 2 for the voltage doubler rectiﬁer. e antenna is designed and simulated using the CST Microwave Studio Suite (Computer Simulation Technology), while the complete rectenna is simulated using Agilent’s ADS tool with good agreement for both simulation and measurements. 1. Introduction anks to microsystems and wireless communications, wireless sensor networks (WSN) have expanded in many applications with energy independence as one of the fun- damental challenges in the implementation of WSN in the real world. Recently, energy harvesting has become popular and wireless power harvesting devices look to be a promising technique for powering sensors’ nodes that can be equipped with powering modules that can convert received electro- magnetic energy into a DC current that can be utilized to charge the local battery. Rectenna, or “rectifying antenna,” is the crucial component that determines the entire system performance. Diﬀerent types of rectennas have been de- veloped for high-power applications. e construction of energy conversion circuits to capture energy from a low power RF dedicated source at high frequencies has recently been the focus of study in wireless power transfer (WPT) [1]. In fact, the higher frequency bands provide a number of advantages, including smaller area, faster transmission rates, better signal penetration, and greater bandwidth [1]. e main challenges for building an eﬃcient rectenna are low intercepted power levels, losses in the matching circuit, diode nonlinearity, and changes in circuit performance with input power level, input frequency, and termination load. All of these issues have been addressed in various literatures during the last few years. A lot of research has gone into developing high-eﬃciency rectennas. Most previous art designs, on the contrary, perform best at high input power, such as greater than 0 dBm [2–5]. Zbitou et al., in [2], have designed an antenna array with eﬃciency 65% for 25 dBm power input. In [3], Hagerty et al. designed a rectenna array, where 20 percent eﬃciency was reached for a power density of 62 μW/cm 2 or equivalently, a power input of 13.27 dBm (for rectenna geometric area of (19 × 23cm 2 ). In [4], Fal- kenstein et al. designed a rectenna with eﬃciency of 54% Hindawi International Journal of Antennas and Propagation Volume 2021, Article ID 1109850, 8 pages https://doi.org/10.1155/2021/1109850