A millimeter-wave circular reflectarray antenna for future 5G cellular networks

A new broadband millimetre-wave reflectarray antenna structure utilizing novel polarization insensitive multi resonant unit cells is proposed. The design frequency of the RA is set at 30 GHz, and it consists of 20×20 polarization independent insensitive resonant unit cells (UCs), which are illuminated by pyramidal horn antenna. The unit cell of this array contains two concentric rings combined with a cross loop and cross strips inside for bandwidth enhancement. For maximum aperture efficiency and realized gain, a pyramidal horn antenna placed at F to obtain F/D=0.4. The simulation results show that the obtained maximum gain is 25.1 dB with a slight variation over the operating frequency range and a good cross-polarization level.