A Ku band oscillator array using positive feedback type push-push oscillators

In this paper, an oscillator array using push-push oscillators and a directional phase shifters for the coupling circuits is presented. In the oscillator array, push-push oscillators are connected via the coupling circuits consisting of directional couplers and a phase shifter. The phase shifter consists of a π/2 hybrid circuit and varactor diodes. An oscillation signal of the push-push oscillator is injected into the adjoining push-push oscillator through the coupling circuit. The push-push oscillators are synchronized by the signal. The phase shifts between the signals of the oscillators are obtained by the phase shifters. In experiment, the phase shift about 140 degrees is obtained between the output signals of adjoining oscillators in Ku band.