With the growing demand for compact, high-performance and reconfigurable antenna systems in mid-band 5G communication (3.3–6 GHz), polarization agility has become essential for improving link reliability and spectral efficiency. This paper presents the design, simulation and experimental validation of a polarization reconfigurable microstrip patch antenna capable of dynamically switching between vertical (VP) and horizontal (HP) linear polarization states using a single RF excitation port. The antenna employs two orthogonal microstrip feedlines connected via PIN diode switches to a common feed, enabling selective excitation of adjacent patch edges. This facilitates activation of the fundamental TM01 or TM10 mode, producing vertical or horizontal polarization, respectively. Fabricated on an FR4 substrate, the antenna features a low-profile, planar configuration ideal for compact RF systems. Simulated and measured resonances occur at 5.31/5.40 GHz (VP) and 5.27/5.33 GHz (HP), respectively. The antenna achieves –10 dB impedance bandwidths of 3.52% (VP) and 6.01% (HP), peak gains of 2.48 dBi and 2.76 dBi and axial ratios above 48 dB, confirming high polarization purity and low cross-polarization. Radiation patterns show good agreement with simulations. The proposed design offers a compact and efficient solution for applications demanding polarization reconfigurability, making it well-suited for advanced wireless communication systems.
Saikia et al. (Thu,) studied this question.