A novel dual-mode design for push-push oscillators with improved phase noise performance

The phase noise of oscillators is related to the loaded Q-factor of the resonator. A novel dual-mode resonator theory has been developed, utilising both even and odd mode by performing internal mode conversions. Thereby the wave is being filtered twice, resulting in steeper phase behaviour than compared to classical mono-mode resonators. This novel resonator concept has been implemented into an oscillator design as a proof of concept. Simulations and first measurements indicate an increased phase noise performance of 6 dB compared to differential mono-mode operation of a push-push oscillator. Simulation results attest outstanding phase noise values 142 dBc/Hz at 1 MHz.