Ring-coupled-oscillator sequentially rotated active antenna

In this paper, an active four-element patch antenna, backed by four GaAs monolithic-microwave integrated-circuit (MMIC) 4.4-GHz oscillators, self-locked by mutual coupling through a lumped capacitive ring MMIC network, has been designed, fabricated, and tested. The sequentially rotated arrangement given here when augmented with a lumped capacitive coupling network suggests that in-phase oscillator entrainment is guaranteed so that spatial power combination by the antenna array occurs with circular polarization characteristics.