A high frequency push-push oscillator is disclosed. The high frequency push-push oscillator includes a resonant circuit, including tank transmission lines or an inductor capacitor (LC) tank circuit, for generating a differential signal having a resonant frequency, and a Gm-core circuit for converting the differential signal to an output signal having an output frequency that is higher than the resonant frequency. The Gm-core circuit includes cross-coupled first and second transistors having first and second gates, drains, and sources, respectively, and first and second gate transmission lines. The first and second drains are in electrical communication with the resonant circuit. The first gate transmission line is joined with the first gate and the resonant circuit and the second gate transmission line is joined with the second gate and the resonant circuit. The Gm-core circuit includes a differential transmission line positioned between the first and second gates of the first and second transistors.