Abstract: This paper presents a novel modified cross-coupled differential-drive (CCDD) rectifier designed for Radio Frequency Energy Harvesting (RFEH) applications. The proposed design incorporates MOSFET-modeled capacitors to reduce area consumption while maintaining a high power conversion efficiency (PCE).Acomprehensive mathematical modelwas developed to analyze the behavior of the circuit, and the Walrus Optimization Algorithm (WaOA) was employed to optimize the transistor aspect ratios. The simulation results demonstrate that the modified rectifier achieves a maximum PCE of 93.24% at an input power of −17.5 dBm, significantly outperforming both the conventional and dual MOSFET-based configurations, particularly at low input power levels. Notably, the proposed design achieves a wide power dynamic range of 25 dB and occupies an ultra-compact area of 35.22μm2, making it suitable for ambient RFEH scenarios. This work represents a significant advancement in RFEH technology, offering a more efficient and compact solution for powering low-energy devices such as Internet of Things (IoT) sensors and wearable electronics.