Results 261 to 270 of about 4,057,523 (305)

Measurement of optical frequencies and frequency ratios

Measurement Science and Technology, 2003
This paper reviews the history of the phase-coherent measurement of optical frequencies, its present status and future prospects. The development of frequency measurement of optical frequency standards with respect to the frequency of the Cs atomic clock is described.
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Optical refractive synchronization frequency sampling ratio amplitude ratio between the clock frequency and the modulated frequency

SPIE Proceedings, 2000
Abstract This paper addresses the equations necessary to evaluate the required samplingfrequency as a function of the ratio of amplitudes between the clock frequencies and thefrequencies that are modulated onto the respective clock frequencies. A key ingredient thatis also involved in the appropriate selection of the sampling frequency is the base ...
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Discrimination of Frequency Ratios

The Journal of the Acoustical Society of America, 1968
It is well known that our natural musical scale is built up out of tones whose frequencies are related by simple whole numbers. A sequence of tones in this scale seems to sound “natural,” while sequences of tones whose frequencies form a more complicated ratio sound “strange” or “unnautral.” The purpose of this research was to determine experimentally ...
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A 65 nm CMOS Statistical Frequency Ratio Calculator for Frequency Measurement

IEEE Transactions on Industrial Electronics, 2021
In this article, the frequency ratio calculator (FRC) based on the statistical algorithm is proposed to obtain the integer and fractional frequency ratios of an input signal and a reference signal. The function of FRC can be used for fast frequency measurement of an unknown signal.
Yun-Chih Lu, Chi-Hung Wu, Yi-Jan Emery Chen   +2 more
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Allowable frequency multiplication ratios in synchrotrons

The Soviet Journal of Atomic Energy, 1958
The energy dependence of the amplitude of synchrotron oscillations due to radiation fluctuations is investigated. A simple stationary solution for the phase equation is obtained; this equation can be applied, with accuracy sufficient for practical purposes, to all large synchrotrons.
E. M. Moroz, M. S. Rabinovich
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Dual-band frequency selective structure with large frequency band ratio

2013 IEEE MTT-S International Microwave Workshop Series on RF and Wireless Technologies for Biomedical and Healthcare Applications (IMWS-BIO), 2013
A dual-band bandpass frequency selective structure (FSS) with large frequency band ratio is presented in this paper. The proposed FSS consists of an array of three-layer printed circuit boards and a number of inserted metallic rods and plates. Under a linearly polarized incident wave with its electric field perpendicular to the printed circuit boards ...
Bo Li, Zhongxiang Shen
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UNCOUPLED FREQUENCY RATIO IN ASYMMETRIC BUILDINGS

Earthquake Engineering & Structural Dynamics, 1996
Structural eccentricity and Uncoupled Frequency Ratio (UFR) are two system parameters that strongly influence the elastic response of eccentric structures. The opinions differ regarding their influence on the inelastic response. Different investigators arrived at contradictory conclusions on the influence of uncoupled frequency ratio.
S. ANNIGERI, A. K. MITTAL, A. K. JAIN
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Miniaturization of dual frequency RFID antenna with high frequency ratio

2007 IEEE Antennas and Propagation Society International Symposium, 2007
We have presented a novel design for dual frequency RFID antenna with high frequency ratio. This antenna works well in both the HF and UHF bands for RFID operation with a single feed. Comparisons between the new design and the previous design are made and the new design is shown to be less than half of the size of the previous design while offering ...
Kin Seong Leong, null Mun Leng Ng, Peter H. Cole   +2 more
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Dual-Frequency Folded-Parallel-Plate Antenna With Large Frequency Ratio

IEEE Transactions on Antennas and Propagation, 2016
This communication investigates a new compact dual-frequency antenna with a large frequency ratio, which consists of a pair of folded parallel plates. It integrates the microwave parallel-plate waveguide resonator antenna (WRA) with the millimeter-wave Fabry-Perot resonator antenna (FPRA), with their resonant frequencies independent of each other.
Li Ying Feng, Kwok Wa Leung
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Simple Frequency Ratios Naturally Make Precisely Perceived Melodies

Current Biology
Almost all human music is built on discrete scales of pitch.1 Culturally prominent scales, such as the diatonic major scale of Western music, make use of the simple frequency ratios 2:1, 3:2, and 4:3 between notes.2 It is generally believed that these ratios were chosen to optimize the consonance of simultaneous notes.3,4,5,6,7 Alternatively, or in ...
Laurent Demany, Catherine Semal, Daniel Pressnitzer   +2 more
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