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Search Publications by: Craig Nelson (Fed)

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Displaying 76 - 100 of 188

Common-Arm Counter-Propagating Interferometer for Fiber Vibration Measurements

November 1, 2011
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
We propose and demonstrate a novel technique to measure the vibration sensitivity of two-port fiber-based optical components. It uses a common-arm counter-propagating frequency-shifted interferometer that cancels the vibration induced phase noise of the

5 MHz Phase Detector With Low Residual Flicker

September 15, 2011
Author(s)
Corey A. Barnes, Archita Hati, Craig W. Nelson, David A. Howe
The measurement of close-to carrier phase modulation (PM) noise of state-of-the-art oscillators is always challenging. Quite often the residual noise of the phase detector used in these measurements is the source of difficulty. In particular at Fourier

Limited Live-time Measurements of Frequency Spectra

July 31, 2011
Author(s)
David A. Howe, Neil Ashby, Danielle G. Lirette, Archita Hati, Craig W. Nelson
Frequency-difference-of-arrival (FDOA) can be used to monitor and track an emitter’s location by observing Doppler frequency shifts of the carrier during short pulsed transmissions. This specific application needs to consider two frequency-stability levels

Residual PM Noise Evaluation of Radio Frequency Mixers

July 31, 2011
Author(s)
Corey A. Barnes, Archita Hati, Craig W. Nelson, David A. Howe
Direct observation of phase modulated (PM) noise is often difficult due to the high dynamic range that exists between the carrier and the modulated sidebands. A common tool used to reduce the dynamic range is the phase detector, which removes the carrier

Vibration Sensitivity of Optical Components: A Survey

July 31, 2011
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We propose and demonstrate a novel technique to measure the vibration sensitivity of two-port fiber-based optical components. It uses a common-arm counter-propagating frequency-shifted interferometer that cancels the vibration induced phase noise of the

Low Vibration Sensitivity Fiber Spools for Laser Stabilization

May 2, 2011
Author(s)
Archita Hati, T Li, B. Argence, A. Haboucha, H. Jiang, J. L. Dornaus, D Kone, A. Clairon, P. Lemonde, G. Santarelli, Craig W. Nelson, E. Burt
Mechanical vibration induced frequency noise is dominated at low Fourier frequencies in a fiber spool stabilized laser. Environmental vibration causes mechanical deformations in the fiber which induce phase fluctuations and then convert into excess

Characterization of Power-to-Phase Conversion in High-Speed P-I-N Photodiodes

February 1, 2011
Author(s)
Jennifer A. Taylor, Shubahshish Datta, Archita Hati, Craig W. Nelson, Franklyn J. Quinlan, Abhay Joshi, Scott A. Diddams
Fluctuations of the optical power incident on a photodiode can be converted into phase fluctuations of the resulting electronic signal due to nonlinear saturation in the semiconductor. This impacts overall timing stability (phase noise) of microwave

High Spectral purity oscillator at 40 GHz: Design using air-dielectric Cavity

June 2, 2010
Author(s)
Archita Hati, Craig W. Nelson, Billy F. Riddle, David A. Howe
We describe the design of a low-PM noise 40 GHz oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator to clean up the PM noise of a commercial 10 GHz dielectric resonator oscillator (DRO) multiplied by four. The

Phase Noise in the Photodetection of Ultrashort Optcial Pulses

June 2, 2010
Author(s)
Jennifer A. Taylor, Franklyn J. Quinlan, Archita Hati, Craig W. Nelson, Scott A. Diddams, Shubahshish Datta, Abhay Joshi
Femtosecond laser frequency combs provide an effective and efficient way to take an ultra-stable optical frequency reference and divide the signal down into the microwave region. In order to convert optical pulses into a usable rf signal, one must use high

Phase noise suppression in frequency comb generators

June 2, 2010
Author(s)
Craig W. Nelson, Archita Hati, J F. Nava-garcia, David A. Howe
We propose an idea to suppress the flicker (1/f) noise in radio frequency (RF) multiplier based frequency comb generators. Comb generators are often used for frequency multiplication in frequency synthesis. In general, comb generators apply high power to a

Phase-lock Loops in Vibration Environments

November 16, 2009
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
A popular scheme for achieving low phase noise across a large range of offset frequencies is to employ an oscillator at an output frequency with low far-from-carrier noise that is phase-locked to a reference that has low close-to-carrier noise. We

Vibration-induced PM and AM noise in microwave components

October 1, 2009
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
The performance of microwave components is sensitive to vibrations to some extent. Among them, microwave cables and connectors, bandpass filters, mechanical phase shifters and some non-linear components are the most sensitive. The local oscillator is one