Switched beam patch array antenna using SPDT GaN HEMT switches

In this paper, a single-fed four-panel 4×1 patch array antenna operating at 2.43 GHz with switched beam capability is proposed. The design allows the beam to be switched between four discrete directions giving 360° coverage. The antenna beam is switched over the azimuth plane for Φ = 0°, Φ = 90°, Φ = 180°, and Φ = 270°. The beam control is achieved by using GaN-based HEMT SPDT switches. Only three SPDT switches are integrated directly into the structure, allowing its nature to be electrically controlled over the desired four directions. Simulated and measured reflection coefficients and radiation patterns for the four cases are presented and discussed, showing good agreement. The antenna gain is around 3.8 dB including switches losses at 2.43 GHz.