An Integrated Flexible Antenna With a Four-Element Parasitic Array for Multibeam Radiation and Solar Energy Harvesting

This communication introduces a flexible multibeam solar antenna integrated with flexible perovskite solar cells (FPSCs), presenting a novel solution for self-powered wearable wireless communication systems. The key innovation of this work is the dual-functional role of the FPSCs, which serve not only as efficient energy harvesters but also as functional radiating elements of the antenna itself. This integration is achieved virtually without compromising the unshaded cell area ratio or electromagnetic performance, all within a fully flexible structure. Fabricated on a polyimide substrate, the antenna features a cross-shaped microstrip coupling feed line that electromagnetically excites four parasitic patches, enabling beam steering in the 5.8 GHz industrial, scientific, medical (ISM) band (5.7–5.82 GHz), generating five distinct beams across two diagonal planes. This capability significantly expands the communication coverage for wearable devices. Measurement results demonstrate a gain range of 5.73–7.28 dBi at 5.8 GHz. The integrated FPSCs provide a stable output voltage of 4.26 V, underscoring the self-sustaining potential of the system. This design establishes a promising paradigm for flexible and self-powered wearable electronics, simultaneously offering dynamic beam control and autonomous power generation.