Indonesian Journal of Electrical Engineering and Computer Science Vol. 24, No. 1, October 2021, pp. 338~346 ISSN: 2502-4752, DOI: 10.11591/ijeecs.v24.i1.pp338-346  338 Journal homepage: http://ijeecs.iaescore.com Compact dual-band RF rectifier for wireless energy harvesting using CRLH technique Marwa Jasim Alhily, Nasr Al-Khafaji, Salim Wadi Communications Department, Engineering Technical Collage-Najaf, Al-Furat Al-Awsat Technical University, Najaf, Iraq Article Info ABSTRACT Article history: Received May 4, 2021 Revised Jul 30, 2021 Accepted Aug 4, 2021 In this paper, a new dual-band radio frequency (RF) rectifier was designed. The proposed design is a low-profile structure with dimensions of 5×5.5 mm 2 owing to the use of lumped elements rather than the conventional transmission lines which occupy large footprints. This property can be potentially exploited to use the proposed rectifier in high dense rectenna arrays to generate high output direct current (DC) voltages. Furthermore, the proposed design adopts the composite right/left-handed composite right left- handed (CRLH) technique to realize the dual-band structure at frequencies of 1.8 and 2.4 GHz. Afterward, the matching circuit was optimized to make sure that it offers good matching. The frequency response shows good matching at both bands which are about -22 and -25 dB respectively. Eventually, the simulated circuit has a conversion efficiency of 52% and output voltages of 0.5 V at -5 dBm for the two bands. Keywords: CRLH matching network Dual-band rectifier RF energy harvesting This is an open access article under the CC BY-SA license. Corresponding Author: Marwa Jasim Alhily Communications Department, Engineering Technical Collage-Najaf Al-Furat Al-Awsat Technical University, Najaf, Iraq Email: marwah@atu.edu.iq 1. INTRODUCTION Energy harvesting is a promising technology since the environment of the internet of things (IoT) network depends highly on sensors, which in turn, they need continuous power sources. This is by itself is a big challenge because batteries should be replaced from one time to another, resulting in a task that is a heavy burden. Thus, looking for an alternative source that constantly provides the required power becomes in high demand. One of the solutions is to scavenge the radio frequency radio frequency (RF) power which is always available in space [1]. Also, there are other types of energy sources which are thermal energy [2], solar energy [3], and vibrations energy [4], and each type has advantages over others. The RF power density in space is 0.2nW/cm 2 -1µW/cm 2 [5]. This power is very low if it is compared to other sources. However, this does not prevent researchers from using the RF because of its continuous availability as mentioned before [6]. The RF power is categorized as indoor (e.g., Wifi) and outdoor (e.g., broadcasting, global system for mobile communication (GSM) and digital television (TV)) [7]. A lot of research has been done in this field of power transmission and energy harvesting, but it is rare to see a rectifier design working simultaneously at more than one frequency band with a small footprint [8]. Both these difficulties will be addressed in this paper to come up with a very compact design, capable to harvest the RF power at 1.8 and 2.4 GHz (i.e., a dual-band structure). As a consequence, the proposed design will be potentially a good candidate to work within an array of rectennas to harvest more power from the atmosphere as much as we can. Various research on single-band matching networks is reported. In [9], a full-wave bridge rectifier is adopted in their design. It is matched only at one single frequency band which is 2.45 GHz and the power is