Simulation and design of broadband W-band flaps antenna

A novel broadband W-band Flaps antenna phase-shifting element which the crossed-dipole with annulus patches is proposed in this paper. Compared to the conventional sing-layer Flaps antenna element, the novel elements can realize much larger phase variation range and higher precision of phase shift as well as expand the bandwidth of the antennae effectively. Based on this element, a single-layer reflectarray antenna operating at 94 GHz is designed. The simulation exhibits perfect performance in the bandwidth and directivity, the 1-dB gain bandwidth which is close to 10.6% is obtained and the peak gain of the center frequency is 18.2 dBi. This proposed element offers a new way to design single-layer millimeter-wave reflectarray antenna.