Search Results - "Galleani, Lorenzo"

Time–frequency analysis of the Galileo satellite clocks: looking for the J2 relativistic effect and other periodic variations by Formichella, Valerio, Galleani, Lorenzo, Signorile, Giovanna, Sesia, Ilaria

“…When observed from the ground, the frequency of the atomic clocks flying on the satellites of a Global Navigation Satellite System is referred to as apparent…”
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Time-Frequency Analysis of the Impulse Response by Galleani, Lorenzo

“…The impulse response is a key function for the analysis and design of systems, therefore understanding its properties is a fundamental problem. To investigate…”
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The Corrected Allan Variance: Stability Analysis of Frequency Measurements With Missing Data by Galleani, Lorenzo, Sesia, Ilaria

“…Atomic clocks are essential elements in a variety of applications, such as global navigation satellite systems. Consequently, monitoring their performances is…”
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Time-Frequency Representation of MIMO Dynamical Systems by Galleani, Lorenzo

“…Many deterministic and random physical signals can be modeled as the output of a multi-input-multi-output (MIMO) dynamical system. Since physical signals are…”
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Robust Detection of Fast and Slow Frequency Jumps of Atomic Clocks by Galleani, Lorenzo, Tavella, Patrizia

“…This paper presents a frequency jump detector for atomic clocks. The detector considers both fast frequency jumps, which are abrupt variations of the clock…”
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Response of Dynamical Systems to Nonstationary Inputs by Galleani, Lorenzo

“…We obtain the time-frequency response of the output of a dynamical system when the input belongs to a class of common nonstationary signals, namely, an…”
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The Dynamic Allan Variance V: Recent Advances in Dynamic Stability Analysis by Galleani, Lorenzo, Tavella, Patrizia

“…The dynamic Allan variance (DAVAR) measures the stability variations of precise clocks and oscillators. When an anomaly occurs, the DAVAR changes with time,…”
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The dynamic Allan Variance IV: characterization of atomic clock anomalies by Galleani, Lorenzo, Tavella, Patrizia

“…The number of applications where precise clocks play a key role is steadily increasing, satellite navigation being the main example. Precise clock anomalies…”
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Nonstationary vibration analysis in the smoothed Wigner domain by Galleani, Lorenzo

“…Dynamical systems represent fundamental models for vibration analysis. When the input of such dynamical systems is nonstationary also the output is…”
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The Transient Spectrum of a Random System by Galleani, Lorenzo

“…The frequency spectrum is a fundamental quantity for the analysis and design of a system. When a system is turned on or off, the frequency spectrum of its…”
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The dynamic Allan Variance III: Confidence and detection surfaces by Galleani, Lorenzo

“…The dynamic Allan variance (DAVAR) is a surface which describes the stability of a high-precision clock with respect to time. When the DAVAR is evaluated from…”
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Nonlinear Transformation of Differential Equations into Phase Space by Cohen, Leon, Galleani, Lorenzo

“…: Time-frequency representations transform a one-dimensional function into a two-dimensional function in the phase-space of time and frequency. The…”
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The dynamic Allan variance II: a fast computational algorithm by Galleani, L.

“…The stability of an atomic clock can change with time due to several factors, such as temperature, humidity, radiations, aging, and sudden breakdowns. The…”
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Decomposition of the instantaneous spectrum of a random system by Galleani, Lorenzo

“…We characterize the nature of the instantaneous spectrum of a random system. We define the instantaneous spectrum as the Wigner spectrum of the state of the…”
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Approximation of the Wigner Distribution for Dynamical Systems Governed by Differential Equations by Galleani, Lorenzo, Cohen, Leon

“…: A conceptually new approximation method to study the time-frequency properties of dynamical systems characterized by linear ordinary differential equations…”
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Detection of atomic clock frequency jumps with the Kalman filter by Galleani, L., Tavella, P.

“…Frequency jumps are common anomalies in atomic clocks aboard navigation system satellites. These anomalous behaviors must be detected quickly and accurately to…”
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Approximating the time-frequency output of a dynamical system for an arbitrary nonstationary input by Galleani, Lorenzo

“…We obtain the approximate analytic time-frequency spectrum of the output of a dynamical system when the input is an arbitrary finite-energy nonstationary…”
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Tracking noise in noise by Cohen, Leon, Galleani, Lorenzo

“…Very often one wants to track one type of noise embedded in another noise. In addition, the noises may be nonstationary. For example, suppose one wants to…”
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The dynamic Allan variance by Galleani, L., Tavella, P.

“…We present and discuss the dynamic Allan variance, a measure of the time-varying stability of an atomic clock. First, the dynamic Allan variance is…”
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Year-long optical time scale with sub-nanosecond capabilities by Formichella, Valerio, Signorile, Giovanna, Thai, Tung Thanh, Galleani, Lorenzo, Pizzocaro, Marco, Goti, Irene, Condio, Stefano, Clivati, Cecilia, Risaro, Matias, Levi, Filippo, Calonico, Davide, Sesia, Ilaria

“…An atomic time scale is a method for marking events and the passage of time by using atomic frequency standards. Thanks to the superior performance of atomic…”
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