A5026868044- Advanced Frequency and Time Standards
- Atomic and Subatomic Physics Research
- Scientific Measurement and Uncertainty Evaluation
- Cold Atom Physics and Bose-Einstein Condensates
- GNSS positioning and interference
- Geophysics and Sensor Technology
- Spectroscopy and Laser Applications
- Cardiovascular Syncope and Autonomic Disorders
- Geophysics and Gravity Measurements
- Advanced Fiber Laser Technologies
- Advanced Electrical Measurement Techniques
- Time Series Analysis and Forecasting
- Advancements in Materials Engineering
- Historical Geography and Cartography
- Scientific Research and Discoveries
- Structural Engineering and Materials Analysis
- Radioactive Decay and Measurement Techniques
- Structural Engineering and Vibration Analysis
- Geological Formations and Processes Exploration
- Optical Network Technologies
- Civil and Structural Engineering Research
- Semiconductor Lasers and Optical Devices
- Mechanical and Thermal Properties Analysis
- Advanced Photonic Communication Systems
- Probability and Statistical Research
Centrum Badań Kosmicznych
2003-2024
Bilfinger (Germany)
2018
Poznan Supercomputing and Networking Center
2016
Bureau international des poids et mesures
2003-2014
University of Virginia Health System
2013
Polish Academy of Sciences
2004
Ośrodek Badawczo-Rozwojowy Urządzeń Mechanicznych (Poland)
2002-2003
Central Office of Measures
2003
In-Q-Tel
2001
Abstract We report a stability below 7 × 10 −17 of two independent optical lattice clocks operating with bosonic 88 Sr isotope. The value (429 228 066 418 008.3(1.9) syst (0.9) stat Hz) the absolute frequency 1 S 0 – 3 P transition was measured an comb referenced to local representation UTC by 330 km-long stabilized fibre link. result verified series measurements on and agrees recommendation Bureau International des Poids et Mesures.
In Poland, an accurate two-way optical fibre time transfer (TWOTT) baseline of 420 km has been developed with a standard uncertainty 112 ps. Meanwhile, the BIPM engaged in pilot project to reduce UTC GNSS calibrations from 5 ns approximately 1.5 ns, for which it calibration scheme, named METODE, associated integrated portable station. The TWOTT and METODE respectively represent world's most advanced method facility.
Absolute frequencies of unperturbed (12)C(16)O transitions from the near-infrared (3-0) band were measured with uncertainties five-fold lower than previously available data. The frequency axis spectra was linked to primary standard. Three different cavity enhanced absorption and dispersion spectroscopic methods various approaches data analysis used estimate potential systematic instrumental errors. Except for a well established frequency-stabilized ring-down spectroscopy, we applied...
The quality of Very Long Baseline Interferometry (VLBI) radio observations predominantly relies on precise and ultra-stable time frequency (T&F) standards, usually hydrogen masers (HM), maintained locally at each VLBI station. Here, we present an operational solution in which the are routinely carried out without use a local HM, but using remote synchronization via stabilized, long-distance fibre-optic link. T&F reference signals, traceable to international atomic timescale (TAI), delivered...
Two-way satellite time and frequency transfer (TWSTFT) is a primary technique for the generation of coordinated universal (UTC). About 20 timing laboratories around world continuously operate TWSTFT using ranging equipment (SATRE19) modems remote comparisons in this context. The precision SATRE as observed today limited by an apparent daily variation pattern (diurnal) results. peak-to-peak have been found high 2 ns some cases. Investigations into origins diurnals so far provided no complete...
Abstract The recently concluded collaborative European project “Robust optical clocks for international timescales” (ROCIT) tackled some of the key challenges on roadmap towards a redefinition SI second. This paper gives an overview progress made improving robustness and automation verifying their uncertainty budgets through coordinated comparison campaigns. It also presents work incorporation into time scales, covering both use to steer local physical scales evaluations hydrogen masers...
We report on the design, assembly, testing, and delivery of a series new cesium fountain primary frequency standards built through commercial scientific collaboration with international users. The based proven National Physical Laboratory solutions, improves reliability, simplicity operation, transportability. complete system consists novel physics package, specially developed optical dedicated electronics for control. present results showing that despite their simplified more compact...
The Polish independent atomic timescale TA(PL) was officially started on 4 July 2001. It is currently based the indications of nine clocks from several laboratories and Lithuania. at are compared using TTS-2 multi-channel GPS receivers developed in cooperation with Bureau International des Poids et Mesures (BIPM). participating institutions linked to Central Office Measures (GUM) Warsaw. computed as a weighted average clocks. This paper presents clock ensemble, data processing outline, some...
Abstract We report a remote, intercontinental frequency comparison between 171 Yb (NMIJ) and 88 Sr (UMK) optical lattice clocks. The frequencies were compared via the Global Positioning System Precise Point technique over period from 10 March 2020, 00:00 UTC until 15 UTC. of clocks yields results with relative uncertainty <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:mrow> <mml:mn>6.3</mml:mn> <mml:mo>×</mml:mo> <mml:msup> <mml:mn>10</mml:mn>...
To continue and improve the earlier studies by different authors [1-4], in 2011 BIPM launched a pilot study on accurate calibration for UTC time links [5]. The goal is to unify link uncertainties ≤ 2 ns. This attainable with `one all' METODE scheme dedicatedly designed travelling calibrator (StdB). result (CM) can be easily converted classic equipment internal delays INTDLY(P1/P2). Nine laboratories participated project [6-16]. An operational guideline drafted used guide tours data...
The OPTIME project creates an ultra-precise time and frequency signals dissemination system based on telecommunication networks. End users obtain access to these without incurring huge costs for the purchase of their own atomic clocks, receive service related laboratories generating international scales, which any precise must be referred. is three main elements: reference laboratories, local repositories fiber optical network with specialized transmission equipment transfers between end...
In the paper we present and briefly characterize methods of remote synchronization atomic clocks. Two groups technical solution are presented, namely employing satellites, especially GPS Common View Way Satelite Time Frequency Transfer group systems, which employs ground-base fiber optic networks. The unidirectional bidirectional time/frequency transfer schemes considered, theirs main limitations pointed out. Finally, newly established clock signals distribution network called Optime is...
The Fidelity consortium is currently implementing and will operate the Galileo Time Service Prototype Facility (GTSPF) in order to deliver Coordinated Universal (UTC) services satellite system during its in-orbit validation phase (due begin 2008). A key element of this plan integrate timing activities into wider time frequency community, including Bureau International des Poids et Mesures (BIPM). main function GTSPF provide parameters for steering System (GST), as realized at Precise Timing...
The OPTIME project creates an ultra-precise time and frequency signals dissemination system based on telecommunication networks. End users obtain access to these without incurring huge costs for the purchase of their own atomic clocks, receive service related laboratories generating international scales, which any precise must be referred. This document describes final stage - developed a self-calibrating, high precision reference optical fiber links ELSTAB devices at AGH University.
Unlike GPS, the GLONASS P-code is broadly accessible. This paper discuss capabilities and prospects in terms of precise time transfer. We have tested common-view transfer using C/A- P-code, over links varying length from about 800 km to 9200 km. The raw GPS data were collected 3S navigation receivers, corrected IGS orbit ionosphere maps. It proposed that be calculated monthly, initially as backup for TAI calculation, later possible official
Two-Way Satellite Time and Frequency Transfer (TWSTFT or TW for short) is one of the primary techniques realization Coordinated Universal (UTC), which computed by International Bureau Weights Measures (BIPM). TWSTFT carried out continuously about 20 timing laboratories around world. One limiting factor performance daily pattern (diurnals) in data. Their peak-to-peak variations were observed as up to 2 ns some extreme cases. They must be attributed equipment on ground satellite transponder,...
The remote synchronization of a Very Long Baseline Interferometry (VLBI) station with "virtual" atomic clock delivered via an optical fiber is described. time and frequency signals are provided from UTC(AOS) laboratory located at distance 345 kilometers the VLBI station. Evaluation carried out by Joint Institute for ERIC presented. To our best knowledge, this first operational fiber-optic link synchronizing observations.
The OPTIME project creates a long range dissemination system for transfer ultraprecise time scale and the references frequency signals in telecommunication networks. highest accuracy signal is available only on fiber optical networks, but other type of networks can be used to with lower adapt it needs different user groups. Article also describes experience gained during an over-a-year experiment connection between Central Office Measures (GUM) Warsaw Astrogeodynamic Observatory (AOS) Borowiec.
Several Polish scientific and commercial institutions are equipped with caesium frequency standards, which can be used for the establishment of a national atomic time scale. The scale will computed from weighted average readings these clocks. All participating laboratories multi-channel GPS C/A code Time-Transfer unit. structure this unit is described in brief: method improves stabilty transfer compared single-channel method. results such comparisons presented.
In this work the clock parameters determination of several timing receivers TTS-4 (AOS, PL), ASHTECH-Z-XII3T (PTB, USNO) and SEPTENTRIO POLARX4TR (ORB,) by use Precise Point Positioning (PPP) technique were presented. The determined for time links based on data delivered frequency laboratories mentioned above. computations cover period from June 1 2012 to May 31, 2013 performed in two modes with 7-day one-month solution all links. All RINEX files which include phase code GPS recorded...
Accurate time transfers are now fully based on space techniques. The recently developed optical fibre technique is expected to be used in the UTC generation future. Some labs operate links using different approaches. In particular, here called Two-Way Optical Fibre Time (and Frequency) Transfer (TWOFT/TWOTFT) of special interest. symmetry propagation conditions both directions allows substantially reducing instability due fluctuations propagation, and its capability self-calibration. first...