Tilted-beam MPA with broad-useful bandwidth

A low-profile, beam tilted microstrip patch antenna (MPA) with broad-useful bandwidth and improved gain is presented. The proposed design comprises of a rectangular MPA and a square-loop unit-cell-based metasurface superstrate with different effective refractive index regions. The beam tilting is achieved by the phenomenon of phase difference produced by the superstrate having different refractive index regions. The experimental results display a maximum beam tilt of 27 degrees in the E-plane at 5 GHz with a slight frequency dependability of 0.013 degrees/MHz. The proposed design also offers a broad-useful bandwidth of 11% centred at 4.82 GHz, while maintaining relativel low antenna height of 0.06 Lambda. Moreover, uniform field distribution due to superstrate provides a maximum gain of 8.4 dBi with a variation <= 1.3 dB.