Second Harmonic Beam Scanning of Active Antenna Array

In order to not only obtain a higher frequency radiation but also scan its beam more widely, an active phased array using second harmonic generation is investigated. The active antenna consists of a FET oscillator which plays two roles in fundamental oscillation and frequency multiplying, and the patch antenna resonated at the second harmonic frequency. In the experiments, the radiated beam of the second harmonic wave from the two element active antenna array was scanned more widely than that in the case of the fundamental wave radiation.