Fundamental wave phase-locked dual-band push-push DRO using out-of-phase Wilkinson power combiner

A new push-push phase-locked dielectric resonator oscillator (PLDRO) with dual-band (C/Ku) output capability is presented. An out-of-phase Wilkinson power combiner is used to provide the fundamental (f ₀) output. The phase-locking is implemented at f ₀ as an alternative to direct locking the push-push output frequency (2f ₀) using prescalers. The push-push PLDRO has shown a fundamental suppression of 35.12 dBc and a second-harmonic suppression of 34.77 dBc at the 2f ₀ output and the f ₀ output, respectively. Experimental results also indicate a maximum spur level of -77.4 dBc, and phase noise values of -109.6 and -143 dBc/Hz at 10 kHz and 1 MHz offsets, respectively, from a 12.6 GHz carrier.