A Beam-Switchable Self-Oscillating Active Integrated Array Antenna Using Gunn Oscillator and Magic-T

Abstract

Herein, a novel self-oscillating active integrated array antenna (AIAA)is proposed for beam switching X-band applications. The proposed AIAA comprises four linearly polarized microstrip antenna elements, a Gunn oscillator, two planar magic-Ts, and two single-pole single-throw (SPST) switches. The in/anti-phase signal combination approach employing planar magic-Ts is adopted to attain bidirectional radiation patterns in the Φ = 90° plane with a simple structure. The proposed antenna can switch its beam using the SPST switches. The antenna is analyzed through simulations, and a prototype of the antenna is fabricated and tested to validate the concept. The proposed concept is found to be feasible; the prototype has an effective isotropic radiated power of +15.•98 dBm, radiated power level of +4.•28 dBm, and cross-polarization suppression of better than 15 dB. The measured radiation patterns are in good agreement with the simulation results.