This paper presents the design, optimization, and performance evaluation of a 2.4/6 GHz radio frequency (RF) energy harvesting system. The energy harvesting system, implemented on an FR-4 substrate with distributed dual-band impedance matching network, and rectifier system optimized for 2.4-and 6-GHz frequency bands with input power levels of −30 to +30 dBm. RF energy harvesting, which utilizes ambient electromagnetic radiation, has emerged as a promising solution for powering low-power electronic devices. In this work, we focus on optimizing the design parameters of an RF energy harvesting system operating at the widely available 2.4-GHz and 6-GHz frequency band. Through simulation, we investigate the influence of various design factors such as antenna design, matching network configuration, and rectifier efficiency on the overall performance of the system. Our goal is to maximize the harvested power while ensuring compatibility with typical IoT devices. The findings of this study provide valuable insights into the design considerations and optimization strategies for developing efficient RF energy harvesting systems for practical applications. The best conversion efficiency (PCE) of 80% at 2.4 GHz is obtained with HSMS-282x diode, while HSMS-286x diode achieves an efficiency of 79% diodes, both diodes from Avago Technology.