This paper provides a comprehensive survey of wireless networks with radio frequency (RF) energy harvesting capabilities, known as RF energy harvesting networks (RF-EHNs). The authors first overview the system architecture, RF energy harvesting techniques, and existing applications of RF-EHNs. They then delve into the circuit design, including antenna design, matching networks, and rectifiers. The paper also reviews communication protocols specifically designed for RF-EHNs and discusses key design issues in various network types, such as single-hop, multi-antenna, relay, and cognitive radio networks. Finally, the authors envision future research directions and practical challenges in RF-EHNs. The paper highlights the advantages of RF-EHNs, such as sustainable power supply and the ability to support applications with quality of service (QoS) requirements, while addressing the challenges of RF energy harvesting, including energy efficiency, power transfer distance, and system complexity.This paper provides a comprehensive survey of wireless networks with radio frequency (RF) energy harvesting capabilities, known as RF energy harvesting networks (RF-EHNs). The authors first overview the system architecture, RF energy harvesting techniques, and existing applications of RF-EHNs. They then delve into the circuit design, including antenna design, matching networks, and rectifiers. The paper also reviews communication protocols specifically designed for RF-EHNs and discusses key design issues in various network types, such as single-hop, multi-antenna, relay, and cognitive radio networks. Finally, the authors envision future research directions and practical challenges in RF-EHNs. The paper highlights the advantages of RF-EHNs, such as sustainable power supply and the ability to support applications with quality of service (QoS) requirements, while addressing the challenges of RF energy harvesting, including energy efficiency, power transfer distance, and system complexity.