Reconfigurable Pixel Antennas Meet Fluid Antenna Systems: A Paradigm Shift to Electromagnetic Signal and Information Processing

Traditionally, antennas and wireless communication technologies have been developed separately. While antennas focus on maximizing the received or transmitted signal strength, communication technologies optimize performance through coding, signal processing, and resource allocation. However, strong antenna signals do not guarantee high-quality communication due to factors such as channel fading and interference. Recently, the fluid antenna system (FAS) has emerged as a paradigm that treats the radiating aperture as a flexible, reconfigurable physical-layer resource and integrates it into the physical-layer design, broadening the scope of system and network optimization and inspiring next-generation reconfigurable antennas. This paradigm naturally couples electromagnetic signal and information processing (ESIP). A key enabler is the reconfigurable pixel antenna (RPA), which offers high degrees of reconfigurability via pixel-level switching. This article explores the integration of RPA into the FAS concept and highlights the unique ESIP opportunities and associated challenges. Experimental results are presented to demonstrate the significant potential of RPA-enabled FAS.