This paper proposes a pixel-based reconfigurable antenna (PRA) design for Fluid Antenna Systems (FAS), which aims to enhance wireless communication performance and reduce implementation costs. The PRA-FAS design meets the requirements of FAS, including 12 FAS ports across 1/2 wavelength, and achieves low switching latency with RF switches. The design is based on an E-slot patch antenna and an upper reconfigurable pixel layer with 6 RF switches. Simulation and experimental results at 2.5 GHz demonstrate that the PRA-FAS can meet the FAS requirements, including port correlation with matched impedance. The key contributions of the paper include pattern covariance matrix analysis, achieving 12 FAS ports within a compact volume, achieving μs latency for port switching, and a two-step method for PRA-FAS design optimization. The prototype's performance is validated through simulation and measurement, showing good agreement with theoretical predictions.This paper proposes a pixel-based reconfigurable antenna (PRA) design for Fluid Antenna Systems (FAS), which aims to enhance wireless communication performance and reduce implementation costs. The PRA-FAS design meets the requirements of FAS, including 12 FAS ports across 1/2 wavelength, and achieves low switching latency with RF switches. The design is based on an E-slot patch antenna and an upper reconfigurable pixel layer with 6 RF switches. Simulation and experimental results at 2.5 GHz demonstrate that the PRA-FAS can meet the FAS requirements, including port correlation with matched impedance. The key contributions of the paper include pattern covariance matrix analysis, achieving 12 FAS ports within a compact volume, achieving μs latency for port switching, and a two-step method for PRA-FAS design optimization. The prototype's performance is validated through simulation and measurement, showing good agreement with theoretical predictions.