Ultra-high performance millimeter-wave oscillator and metrology

We report a new class of millimeter-wave oscillators spanning 250 GHz to 400 GHz. Based on photomixing of two optical lines generated by a 75 m long fiber-ring cavity, record low power spectral density of phase noise is achieved reaching − 118 dBc/Hz at 1 MHz Fourier frequency for a 300 GHz millimeter-wave carrier. Together with a state-of-the-art oscillator we have implemented experimental tools to characterize the noise performance of ultra-low noise millimeter-wave oscillator to unprecedented levels, without the need for a microwave local oscillator.