A Ku-Band Injection-Locked Push-Push Oscillator Using Two-Wavelength Ring Resonator

This paper presents an injection-locked push-push oscillator which generates the second harmonic signal in Ku-band. Two sub-oscillators operate in-phase at the same fundamental frequency in a two-wavelength ring resonator. Moreover, two external injection signals are placed on the resonator at a half-wavelength between the sub-oscillators. The oscillator does not require additional phase-shift between the injection signals, and this task is done by the resonator and the power combining circuit. The push-push principle is satisfied by synchronization due to the phase relation of the sub-oscillators and the external injection signal source. Phase noise improvement was achieved by the injection locking.