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Search Publications by: Craig Nelson (Fed)

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Displaying 51 - 75 of 205

Collapse of the Cross-spectral Function

May 22, 2014
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of amplitude and phase conditions

Correlation Measurements between PM and AM Noise in Oscillators

May 22, 2014
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We discuss techniques for measuring the correlation between phase modulated (PM) and amplitude modulated (AM) noise in an oscillator and report results of such correlation in a few selected oscillators of similar size, weight, power consumption and

A collapse of the cross-spectral function in phase noise metrology

February 25, 2014
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of conditions where the detection of

Phase inversion and collapse of the cross-spectral function

December 5, 2013
Author(s)
Craig W. Nelson, Archita Hati, David A. Howe
Cross-spectral analysis is a mathematical tool for extracting the power spectral density of a correlated signal from two time series in the presence of uncorrelated interfering signals. We demonstrate and explain a set of conditions where the detection of

State-of-the-Art RF Signal Generation From Optical Frequency Division

September 2, 2013
Author(s)
Archita Hati, Craig W. Nelson, Corey A. Barnes, Danielle G. Lirette, Tara M. Fortier, Franklyn J. Quinlan, Jason A. DeSalvo, Andrew D. Ludlow, Till P. Rosenband, Scott A. Diddams, David A. Howe
We present the design of a novel, ultra-low phase-noise frequency synthesizer implemented with extremely low noise regenerative frequency dividers. This synthesizer generates eight outputs viz. 1.6 GHz, 320 MHz, 160 MHz, 80 MHz, 40 MHz, 20 MHz, 10 MHz and

Photonic microwave generation with high-power photodiodes

May 14, 2013
Author(s)
Tara M. Fortier, Franklyn J. Quinlan, Archita Hati, Craig W. Nelson, Jennifer A. Taylor, Yang Fu, Joe Campbell, Scott A. Diddams
We utilize and characterize high-power, high-linearity modified uni-traveling carrier (MUTC) photodiodes for low-phase-noise photonic microwave generation based on optical frequency division. When illuminated with 980 nm picosecond pulses from a repetition

Exploiting shot noise correlations in the photodetection of ultrashort optical pulse trains

March 10, 2013
Author(s)
Franklyn J. Quinlan, Tara M. Fortier, Haifeng (. Jiang, Archita Hati, Craig W. Nelson, Yang Fu, J. C. Campbell, Scott A. Diddams
Photocurrent shot noise represents the fundamental quantum limit of amplitude, phase and timing measurements of optical signals. It is generally assumed that non-classical states of light must be employed to alter the standard, time-invariant shot noise

Phase-Noise Measurement System for the Terahertz-Band

November 30, 2012
Author(s)
Jason A. DeSalvo, Archita Hati, Craig W. Nelson, David A. Howe
We present initial phase noise measurements in support of terahertz electronics, in the frequency range generally regarded as 0.1 to 10 THz. Using digital phase noise measurement techniques and an even-harmonic mixer, we achieve a phase noise measurement

Ultra-low noise regenerative frequency divider

November 11, 2012
Author(s)
Archita Hati, Craig W. Nelson, Corey A. Barnes, Danielle G. Lirette, Jason A. DeSalvo, David A. Howe
We designed ultra-low noise regenerative divider-by-2 circuits that operate at input frequencies of 20 MHz and 10 MHz. We achieved residual output-referred single-sideband phase noise below -162 dBc/Hz at 10 Hz offset for a single divider at these

A Sub-Sampling Digital PM/AM Noise Measurement System

September 1, 2012
Author(s)
Craig W. Nelson, David A. Howe
A digital phase/amplitude modulation (PM/AM) noise measurement systems (DNMS) implementing field progammable gate array (FPGA) based digital down converters (DDCs), and 250 MHz analog to digital converters (ADCs) is reported. Measurements in the first

Calibration uncertainty for the NIST PM/AM noise standards

July 31, 2012
Author(s)
Archita Hati, Craig W. Nelson, Neil Ashby, David A. Howe
NIST provides an on-site calibration service of the accuracy of phase modulation (PM) noise, amplitude modulation (AM) noise and noise floor of the measurement systems at a customer's site using one or more portable PM/AM secondary noise standards. In this

Sub-femtosecond absolute timing jitter with a 10 GHz hybrid photonic-microwave oscillator

June 7, 2012
Author(s)
Tara M. Fortier, Craig W. Nelson, Archita Hati, Franklyn J. Quinlan, Jennifer A. Taylor, Haifeng (. Jiang, Chin-Wen Chou, Till P. Rosenband, Nathan D. Lemke, Andrew D. Ludlow, David A. Howe, Christopher W. Oates, Scott A. Diddams
We present an optical-electronic approach to generating microwave signals with high spectral purity. By overcoming shot noise and operating near fundamental thermal limits, we demonstrate 10 GHz signals that have timing deviation from an ideal periodic