360° Beam-Steering Reconfigurable Wideband Substrate Integrated Waveguide Horn Antenna

A novel beam-steering reconfigurable substrate integrated waveguide (SIW) horn antenna is presented. By employing p-i-n diodes as tuning mechanisms, the states of copper posts of the SIW horn can be electronically controlled. Accordingly, the aperture direction of the horn can be switched, and a 360° beam-scanning ability is realized. A pair of bowl-shaped reflectors is introduced for achieving a wide impedance bandwidth and good directional radiation patterns. A fully functional prototype with a 26.2% impedance bandwidth is developed and tested, demonstrating the antenna with a measured gain varying between 8 and 10 dBi and a radiation efficiency of approximately 75% over the impedance band. Moreover, owning to its symmetrical structure, the proposed antenna is capable of steering the radiation beam every 22.5° with identical radiation patterns in the H-plane.