U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Publications by: David A. Howe (Assoc)

Search Title, Abstract, Conference, Citation, Keyword or Author
Displaying 76 - 100 of 124

W-band dual channel AM/PM noise measurement system - an update

August 29, 2005
Author(s)
Archita Hati, Craig Nelson, J Nava, David A. Howe, Fred L. Walls, Huascar Ascarrunz, Justin Lanfranchi, Bill Riddle
We discuss the performance of a W-band (92-96) GHz amplitude modulated (AM) and phase modulated (PM) noise measurement system. The system uses two nearly identical channels to measure the residual noise in amplifiers in pulsed mode with a duty cycle of 10%

Enhancements to GPS Operations and Clock Evaluations using a Total Hadamard Deviation

August 1, 2005
Author(s)
David A. Howe, Ron Beard, C. A. Greenhall, F. Vernotte, W. J. Riley, Trudi K. Peppler
We describe a method based on the Total deviation approach whereby we improve the confidence of the estimation of the Hadamard deviation that is used primarily in GPS operations. The Hadamard-total deviation described in this paper provides a significant

Low Phase Noise Amplifier and Oscillator Using Feed-Forward Technique at 10 GHz

June 1, 2005
Author(s)
Archita Hati, Craig W. Nelson, David A. Howe
We discuss the performance of a feed-forward amplifier (FFA) at 10GHz. The feed-forward method is primarily used to suppress intermodulation distortion in amplifiers to suppress up-converted near-DC noise. The main amplifier in this configuration is a low

Frequency Stability, ed. by K. Chang

January 1, 2005
Author(s)
David A. Howe
This chapter introduces the concept of frequency stability measurements of oscillators by the Allan Deviation and spectral analysis. Examples and typical results are presented. Physical interpretations of common noise processes are discussed.

Theo1 Confidence Intervals

August 23, 2004
Author(s)
T Tasset, David A. Howe, Donald B. Percival
Theoretical variance #1 (Theo1) has been developed at NIST to improve the estimation of long-term frequency stability. Its square-root (Theo1-dev) has two significant improvements over the Allan deviation XX called ¿Adev" in estimlating long-term frequency

Theo1: Characterization of very long-term frequency stability

August 23, 2004
Author(s)
David A. Howe, T Tasset
Theo1 is the first new species of variance that addresses a particularly difficult measurement problem, namely, obtaining reliable estimation of frequency stability for sample periods that are long compared to the length of a data run. Theo1 has

W-band dual channel PM/AM noise measurement system

August 23, 2004
Author(s)
Archita Hati, Craig Nelson, J Nava, David A. Howe, Fred L. Walls
We discuss the performance of a W-band (92 to 96 GHz) PM and AM noise measurement system. The system uses two nearly identical channels to measure the AM or P M noise added by an amplifier or any passive component. It is principally designed to measure

Clock Jitter Estimation based on PM Noise Measurements

January 1, 2003
Author(s)
David A. Howe, T Tasset
"Jitter" is the noise modulation due to random time shifts on an otherwise ideal, or perfectly on-time, signal transition. In the absence of ultra-high-speed jitter analyzers, spectrum analysis is an alternate noise measurement for timing jitter

High-Spectral-Purity Microwave Oscillator: Design Using Conventional Air-Dielectric Cavity

January 1, 2003
Author(s)
A Sen Gupta, David A. Howe, Craig Nelson, Archita Hati, F L. Walls, J F. Garcia nava
We report exceptionally low PM and AM noise levels from a microwave oscillator that uses a conventional air-dielectric cavity resonator as a frequency discriminator. Our approach is to increase the discriminator's intrinsic signal-to-noise ratio by use of

Noise Figure vs. PM Noise Measurements: A Study at Microwave Frequencies,

January 1, 2003
Author(s)
Archita Hati, David A. Howe, F L. Walls, D. Walker
This paper addresses two issues: (i) it compares the usefulness of phase-modulation (PM) noise measurements vs. noise figure (NF) measurements in characterizing the merit of an amplifier, and (ii) it reconciles a general misunderstanding in using -174 dBc

Measuring Clock Jitter at 100 GHz from PM Noise Measurements

June 3, 2002
Author(s)
David A. Howe
"Jitter" is the noise modulation due to random time shifts on an otherwise ideal, or perfectly on-time, signal transition. This paper presents ways of calculating timing jitter using phase- modulation (PM) and amplitude-modulation (AM) noise measurements