The performance of newer generations of ultra high stability atomic frequency standards based on laser cooled atoms and ions appears to be limited by the local oscillator and the microwave synthesis chain. To improve this performance, the design considerations of microwave synthesizers for Cs hyperfine clock transition at 9.192 GHz that emphasize high resolution, low phase modulation (PM) and a...

Micro and nano electromechanical resonators have been widely used as single or multiple-mass detection sensors. Smaller devices with higher resonance frequencies and lower masses offer higher mass responsivities but suffer from lower frequency stability. Synchronization phenomena in multiple MEMS resonators have become an important issue because they allow frequency stability improvement, there...

We report on the experimental test of a new concept for reducing limitation on short-term frequency stability of passive frequency standards due to local oscillator phase noise. Systems that use sinewave modulation to interrogate a stable resonance are limited in short-term frequency stability by phase noise at the second harmonic of the modulation, f,. This effect limits the fractional frequen...

MICROWAVE signal sources of high fre quency-stability and spectral purity are increasingly important to many fields. These include doppler systems, nuclear spectroscopy measurements, spectrum analyzers, as well as telemetry, radio astronomy, and other com munications-type work. All of these applica tions are characterized by the need for good shortand long-term stability as well as low residual...

this paper presents a cooperative control which is applied to the secondary control of a microgrid controlled via a multi-agent scheme. balancing power that leads to voltage and frequency stability in a microgrid is essential. the voltage and frequency regulations are limiting within the specified limits and conveying them to their nominal values. limiting and conveying the voltage and frequenc...

Islanding operation is one of the main features of a MicroGrid (MG), which is realized regarding the presence of distributed energy resources (DERs). However, in order to deal with the control challenges, which an MG faces during island operation, particularly when the transition is associated with certain excessive load, an efficient control strategy is required. This paper introduces a Centra...

This paper presents a comprehensive review on enhancement of power system stability such as rotor angle stability, frequency stability, and voltage stability by using different FACTS controllers such as TCSC, SVC, SSSC, STATCOM, UPFC, IPFC in an integrated power system networks. Also this paper presents the current status of the research and developments in the field of the power system stabili...

We demonstrate that first-order light shifts can be canceled for an all-optical, three-photon-absorption resonance (N-resonance) on the D1 transition of 87Rb. This light-shift cancellation facilitates improved frequency stability for an N-resonance clock. For example, by using a tabletop apparatus designed for N-resonance spectroscopy, we measured a short-term fractional frequency stability (Al...

A basic measure of an oscillator’s performance is its frequency stability (or instability depending on one’s point of view). In the long term (timescales of days or years), we refer to frequency changes as aging. On moderate timescales (seconds), the stability of an oscillator is often characterized in terms of its Allan variance [1]. On short timescales (usually less than one second), frequenc...

We report on direct stabilization of a femtosecond laser by a high-finesse passive optical cavity. Detailed comparison of two distinct stabilization schemes leads to new understanding of the optimum conditions for cavity stabilization and limitations on the ability to transfer the frequency stability of the cavity to the microwave domain. The stability of the frequency comb is explored in both ...