An increasing number of radar, quantum, and other RF systems are relying on direct sampling to maintain accuracy and speed from the microwave band and beyond. Direct sampling systems require extremely high-speed analog to digital converters and digital to analog converters (ADCs and DACs) to accurately transform data from RF to digital signals. Because ADCs and DACs only experience phase noise contributions from the noise floor and 1/f noise, a burden is put on the local oscillators to optimize phase noise contribution and overall performance. Quartz, SAW, dielectric, and air cavity oscillators have been historically constrained by the noise penalty caused by multiplying the signal up to X-band frequencies. Sapphire-loaded cavity oscillators (SLCOs) can resolve that tradeoff by operating in whispering-gallery mode within a low loss sapphire resonator at 8 to 12 GHz. For system designers, the result is a straightforward path to improved range, resolution, and fidelity for radar, test and measurement, and quantum systems.
In this white paper from Marki Microwave, learn more about different oscillator types, their use cases, and the merits of SLCOs in comparison to different oscillator constructions.
