# A Broadband MS-Based Circularly Polarized Antenna Array Using Sequential-Phase Feeding Network

## TL;DR

This paper presents a compact, high-gain, broadband circularly polarized antenna array for C-band satellite communication.

## Contribution

The design introduces a metasurface-based antenna array with a sequential-phase feeding network for enhanced bandwidth and gain.

## Key findings

- The antenna achieves a 20% operating bandwidth with a peak broadside gain of 10.5 dBi.
- The design overlaps a 29.8% impedance bandwidth with a 20% axial ratio bandwidth.
- The proposed array is more compact and efficient compared to recent similar designs.

## Abstract

This paper introduces the design of a circularly polarized metasurface-based antenna array for C-band satellite applications that owns broadband operation and high gain characteristics. The single radiating element comprises a Y-shape patch and an above-placed 2 × 2 unit-cell metasurface. Further improvement in operating bandwidth and broadside gain is achieved by arranging four single elements in a 2 × 2 configuration and a sequential-phase feed network. A prototype has been fabricated and measured to validate the feasibility of the proposed antenna array. The measured operating bandwidth is 20% (4.50–5.50 GHz), which is an overlap between a −10 dB impedance bandwidth of 29.8% (4.50–5.99 GHz) and a 3 dB axial ratio bandwidth of 20% (4.50–5.50 GHz). Across this operating band, the peak broadside gain is 10.5 dBi. Compared with the recently published studies, the proposed array is a prominent design for producing a wide operating bandwidth and relatively high gains while maintaining the overall compact dimensions.