A Miniaturized Flexible Fractal Rectenna for Wireless Communication and Power Transfer

This paper proposes a miniaturized fractal rectenna to address the demands of integration and small size in wireless communication and wireless power transfer (WPT) system. The miniaturized fractal antenna adopts a three-layer symmetric stacked structure, all fabricated by felt material that provide mechanical stability and electromagnetic isolation. The radiation patch layer uses a square patch with slots etched at the centers of its four sides to optimize miniaturization and radiation performance; the transmission line layer employs two vertically placed parallel lines to enhance electromagnetic coupling attenuation and reduce port crosstalk; the ground layer uses a PEC plate matching the substrate size to ensure good grounding and electromagnetic shielding. For the WPT system, a rectifier is integrated to convert the AC power received by the antenna into usable DC power. In terms of performance, the antenna with two ports both resonates at 2.45 GHz, with a high-gain of 3.8 dBi and 3.8 dBi; the integrated WPT system effectively achieves power reception and conversion via the rectenna, enabling 65% conversion efficiency. This miniaturized fractal rectenna can potentially provide structural design references and performance data support in wireless communication fields (e.g., small-scale IoT devices, portable communication terminals) and low-power SWIPT scenarios (e.g., wirelessly powered sensors, wearable electronic devices).