Full Band CP Ferrite-Based Satellite Feed Structure for LEO Satellite Applications

Circular polarization (CP) systems are vital in modern satellite communication. They reduce multipath interference, maintain the purity of polarization, and ensure reliable signal transmission and reception across a wide range of frequencies. Low Earth Orbit (LEO) satellites are becoming popular in the wireless communications field. They will play a significant role in future wireless communication networks. At the center of these systems, orthomode transducers (OMTs) and polarizers are essential components. They efficiently separate and convert orthogonal modes into right-hand and left-hand circularly polarized signals. However, conventional OMT and polarizer designs often struggle to achieve a compact size, a wide bandwidth, and high isolation simultaneously. This paper combines a high-performance OMT with a ferrite-based polarizer optimized for the 19.5–29.5 GHz band. The proposed OMT demonstrates low insertion loss, high return loss, and a small footprint. These features tackle the limitations of traditional twofold designs. The ferrite polarizer, made of segmented slabs and matching posts, provides a flat phase response and excellent thermal stability. Experimental measurements of the built OMT closely match the simulations. When paired with the ferrite polarizer, the overall CP system shows improved bandwidth, axial ratio, and isolation, making it a strong candidate for future satellite communication systems.