F
Fred L. Walls
Researcher at National Institute of Standards and Technology
Publications - 121
Citations - 3780
Fred L. Walls is an academic researcher from National Institute of Standards and Technology. The author has contributed to research in topics: Phase noise & Noise spectral density. The author has an hindex of 31, co-authored 121 publications receiving 3673 citations. Previous affiliations of Fred L. Walls include United States Department of the Army & University of Washington.
Papers
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Proceedings ArticleDOI
A review of sensor sensitivity and stability
John R. Vig,Fred L. Walls +1 more
TL;DR: In this paper, the resonator instabilities that lead to the conclusions that sensitivity expressed as Hz per unit of measurand is not a good measure of sensor quality, and when compared on the bases of accuracy, reproducibility, and resolution capability, "good" low frequency sensors are often superior to high frequency ones.
Proceedings ArticleDOI
Extending the range and accuracy of phase noise measurements
TL;DR: In this article, a survey of traditional precision techniques for measuring phase noise is provided as a basis for comparing relative performance and limitations, and several calibration techniques are developed which, when combined with two previous oscillator techniques, permit one to calibrate all factors affecting the measurements of phase noise of oscillator pairs to an accuracy which typically exceeds 1 dB and in favorable cases can approach 0.4 dB.
Journal ArticleDOI
RF Spectrum of a Signal after Frequency Multiplication; Measurement and Comparison with a Simple Calculation
Fred L. Walls,Andrea Demarchi +1 more
TL;DR: In this paper, the effect of frequency multiplication on the RF spectrum of an oscillator has been studied and a simplified theory is developed and shown to reproduce the experimental results for the relative power in the carrier and noise pedestal, and the shape and the width of the carrier.
Journal ArticleDOI
Origin of 1/f PM and AM noise in bipolar junction transistor amplifiers
TL;DR: This study provides the functional dependence of 1/f AM and PM noise on transistor parameters, circuit parameters, and signal frequency, thereby laying the groundwork for a comprehensive theory of 2/f PM and AM noise in BJT amplifiers.
Journal ArticleDOI
Performance evaluation of an optoelectronic oscillator
TL;DR: Phase noise measurements of an optoelectronic oscillator (OEO) at frequencies less than 10 Ha from the carrier as well as the measured Allan variance are presented for the first time.