The Uliss exceptional frequency performances essentially comes from our deep expertise in the Sapphire Whispering Gallery Mode Resonator technology that has been gained through research and development activities leaded in the Femto-ST Institute since more than 15 years.
To achieve the required oscillator frequency stability, the oscillator's sapphire resonator must be maintained in a cryogenic environment that is sufficiently free of mechanical vibration and where the resonator's temperature is uniform and precisely controlled at a specific value.
A 2.5 GHz Dielectric Resonator Oscillator (DRO) chosen for its low phase noise is frequency multiplied by 4 and mixed with the CSO's signal. The resultant beatnote is compared to the signal coming from a DDS. The resulting error signal is used to phase lock the DRO to the CSO. Frequency dividers complete the system to generate the 100 MHz and 10 MHz frequencies from the 10 GHz signal.