Physics

Microstrip

Bandwidth (computing)

Turnstile antenna

Optics

Computer graphics (images)

Planar

Physical chemistry

Circular polarization

Patch antenna

Microstrip antenna

Antenna (radio)

Chemistry

Polarization (electrochemistry)

Axial ratio

Computer science

Broadband

Telecommunications

Coaxial antenna

IEEE Transactions on Antennas and Propagation

We propose a low-profile broadband planar circularly polarized folded transmitarray antenna (CPFTA) based on well-designed top and bottom metasurfaces (MSs). The top MS is employed to reflect the x-polarized wave as a ground and, at the same time, to convert the y-polarized wave into circularly polarized waves with arbitrary phase shifts in the operation band. A bottom MS is applied to reflect the incident wave and twist its polarization by 90°. The whole CPFTA, including the feeding source of microstrip antenna, and the top and bottom MSs can be fully integrated and fabricated using low-cost printed circuit board technology. Both simulated and measured results demonstrate significant advantages of the proposed antenna, including broad bandwidth, high gain, lower profile, planar geometry, and easy integration. The fabricated sample shows 3 dB axial ratio (AR) bandwidth of 23.2%, 3 dBi gain bandwidth of 11.6%, and the maximum gain of 22.8 dBi at 10.3 GHz with the antenna efficiency of 21.8%. The proposed CPFTA is promising for applications in satellite communications with circularly polarized antennas.

Folded Transmitarray Antenna With Circular Polarization Based on Metasurface