Oscillation is a common phenomenon to virtually all areas of science. Many products in the marketplace use oscillators as a means of keeping time such as the quartz crystal used in modern watches. These oscillators, while commonly used, exhibit a variety of instabilities resulting from aging, noise, and frequency changes caused by factors such as: temperature, acceleration, ionizing radiation, power supply voltage, shock, and vibration. These instabilities impart noise to the circuit resulting in numerous adverse effects on system performance.
Researchers at Rutgers have developed a system and method for reducing noise and improving the quality factor of resonators used in precision oscillators. Noise reduction and quality factor improvement (Q) of the frequency source come from using a lower harmonic mode. Using the lower harmonic mode has the benefits of 1)a quality factor that is nominally three times higher than the next higher overtone mode,2) reduces the bandwidth of the lower mode resonance curve, and (3) increases the slope of the lower harmonic phase frequency curve. These three characteristics of the lower harmonic mode when coupled nonlinearly to the higher harmonic mode improve the quality factor and reduce the noise of the higher harmonic mode. The method is applicable to all resonators that (a) have symmetric boundary conditions, (b) are excited either symmetrically or anti-symmetrically, and (c) have nonlinear elastic constants. For example, their method could be used in quartz crystal resonators that employ thickness shear vibrations, (b) flexural vibrations, or (c) extensional vibrations if the said vibrations are either symmetric or anti-symmetric, and the said vibrations could be excited into the nonlinear regime.
- Precision Oscillators
- Global Positioning System
- Radar Systems
- Frequency Controlled applications
- Reduces Noise
- Improves Quality Factor
Intellectual Property & Development Status:
Patent pending. Available for licensing and/or research collaboration.