High-Gain Sequentially Rotated LHCP Metasurface Antenna Array for Uplink Ka-Band CubeSat Applications

This paper presents a compact circularly polarized 2 × 2 microstrip antenna array with a metasurface superstrate designed for Ka-band uplink CubeSat communication applications. The proposed antenna array operates at 28 GHz and consists of four-square patch elements arranged in a sequential rotation, connected through a sequential-phase feed network to achieve stable circular polarization. To enhance gain and axial ratio performance, a 6 × 6 rotated plus-shaped metasurface layer composed of periodic unit cells is placed above the antenna array.The antenna structure, with overall dimensions of 22 × 20 × 6.04 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sup>, is designed and simulated using ANSYS HFSS. Simulation results demonstrate an impedance bandwidth of 8.12% (26.74–29.00 GHz) for |S<inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">11</inf>| < -10 dB and a 3-dB axial ratio bandwidth of 1.52% (27.42–27.84 GHz). The antenna array achieves broadside LHCP achieves a maximum gain of 14.8 dBi at 27.5 GHz with a half-power beamwidth of 9° along the Phi = 90° plane. The inclusion of the metasurface layer results in a gain improvement of approximately 5.2 dBi and with a peak gain of 15.5 dBi and a total efficiency greater than 95%.