Advancements in Antenna and Rectifier Systems for RF Energy Harvesting: A Systematic Review and Meta-Analysis  
[PERSON]  
1 Research Group on Applied Embedded Hardware (GIHEA), Universidad Politecnica Salesiana,  
Cuenca 010102, Ecuador, [EMAIL_ADDRESS](P.A.C.-P.); jordonezo@ups.edue (J.O.O.-O.) [PERSON]  
2 Research Group on Telecommunications and Telematics (GITEL), Universidad Politecnica Salesiana,  
Cuenca 010102, Ecuador, [EMAIL_ADDRESS] (N.A.C.-R.)  
[PERSON]  
2 Research Group on Telecommunications and Telematics (GITEL), Universidad Politecnica Salesiana,  
Cuenca 010102, Ecuador, [EMAIL_ADDRESS] (N.A.C.-R.)  
[PERSON]  
1 Research Group on Applied Embedded Hardware (GIHEA), Universidad Politecnica Salesiana,  
Cuenca 010102, Ecuador, [EMAIL_ADDRESS](P.A.C.-P.); [EMAIL_ADDRESS] (J.O.O.-O.) [PERSON]  
2 Research Group on Telecommunications and Telematics (GITEL), Universidad Politecnica Salesiana,  
Cuenca 010102, Ecuador, [EMAIL_ADDRESS] (N.A.C.-R.)  
Footnote 1: email: [EMAIL_ADDRESS]; Tel. : +593-987053450}  
Footnote 2: email: [EMAIL_ADDRESS]; Tel. : +593-987053450}  
Footnote 3: email: [EMAIL_ADDRESS]; Tel. : +593-987053450}  
Footnote 4: email: [EMAIL_ADDRESS]; Tel. : +593-987053450}  
Footnote 5: email: {jgu  
Among the potential sources for energy harvesting are solar light [4], piezoelectric energy [5], radio frequency (RF) signals [6; 7; 8], and other environmental phenomena such as temperature gradients and vibrations [9]. The collection of ambient electromagnetic energy has gained particular interest for powering small wireless electronic devices due to the ubiquitous nature of RF signals in modern environments [10]. This approach not only provides a sustainable energy source but also reduces dependency on traditional power supplies and batteries, which are often environmentally harmful. Energy harvesting from RF signals, in particular, offers unique advantages due to the widespread presence of RF sources such as television broadcasts, cellular networks, and Wi-Fi signals. This omnipresence makes RF energy harvesting an attractive option for powering a wide range of low-power electronic devices and sensors, especially in urban environments where RF signals are abundant [11]. The potential applications of energy harvesting technology are vast and varied. In the Internet of Things (IoT), for instance, energy harvesting can provide a reliable power source for distributed sensors and devices, reducing the need for battery replacements and maintenance [12]. In wearable technology, energy harvesting can extend the battery life of devices such as smartwatches and health monitors, making them more convenient and user-friendly [13]. Implantable biomedical devices also stand to benefit significantly from this technology, as energy harvesting can potentially eliminate the need for surgical battery replacements, thereby improving patient outcomes and reducing healthcare costs [14]. In this context, this article presents an updated and comprehensive review of works related to the development of antennas focused on energy harvesting. We highlight the most recent innovations in receiver antenna design and high-performance rectifier circuit topologies. Key parameters determining the conversion efficiency of harvesting antennas (also known as rectennas) are analyzed in depth, including antenna gain, bandwidth, and impedance matching [15]. Furthermore, we discuss the integration of these antennas with power management circuits, which are crucial for developing efficient energy harvesting systems [16]. A significant portion of the review is dedicated to miniaturized and high-performance antenna designs, as these are critical for applications where space and weight are limited. Recent advancements in materials science and fabrication techniques have enabled the development of antennas with improved performance metrics such as higher gain, wider bandwidth, and better environmental robustness [2; 5; 17].