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Passive phase noise cancellation scheme
Eyal Kenig1, M C Cross, Ron Lifshitz
1Kavli Nanoscience Institute and Condensed Matter Physics, California Institute of Technology, MC 149-33, Pasadena, California 91125, USA.
Physical Review Letters
|September 26, 2012
Summary
We developed a novel passive device using coupled nonlinear resonators to significantly reduce phase noise in oscillators. This method enhances frequency precision by creating a self-oscillating signal immune to driving oscillator noise.
Area of Science:
- Physics
- Electrical Engineering
- Signal Processing
Background:
- Phase noise in oscillators degrades frequency precision.
- Conventional methods for noise reduction often require active feedback systems.
Purpose of the Study:
- Introduce a new passive method for reducing oscillator phase noise.
- Improve the frequency precision of oscillators.
Main Methods:
- Utilized a passive device with coupled nonlinear resonating elements.
- Parametrically drove the resonators with an external oscillator near the sum of linear mode frequencies.
- Investigated self-oscillations above the parametric instability threshold.
Main Results:
- Demonstrated a self-oscillating signal immune to phase noise from the driving oscillator.
- Achieved significant reduction in phase noise, enhancing frequency precision.
- Analyzed the impact of thermal noise on device performance and fundamental limits.
Conclusions:
- The passive coupled resonator device effectively cleans phase noise from oscillators.
- This method offers a promising alternative to active feedback for improving frequency stability.
- Further research on thermal noise effects is crucial for understanding operating limits.
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