Design of a Wideband Circularly Polarized ARMA Antenna Using Characteristic Mode Analysis for SATCOM Applications

A wideband, circularly polarized (CP) agile radiating matrix antenna (ARMA) composed of single elements called pixel is proposed in this article. A pixel is a single-fed cavity-backed antenna made of a microstrip patch and a frequency selection surface (FSS) with specific shaped metasurfaces (MTS). The pixel antenna is designed for operation in the X-/Ku-band and achieve good operation bandwidth of 10.51%. This AR bandwidth is achieved thanks to the combination of the CP patch and CP FSS. The rectangular patch is used as a driving element to generate CP polarized wave. Then the rectangular MTS structure is used to enhance the CP. The compact size of a pixel makes it suitable for beam-scanning in SATCOM applications. Use in matrix of several elements, the matrix antenna achieves better than 3 dB scan loss to ±40° and offers AR below 3 dB over the entire proposed scan range.