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fist version of time and freq transfer section

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papers/ISPCS2018/wrApplicationsOverview.bib
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......@@ -291,4 +291,116 @@ howpublished = "{\url{http://accelconf.web.cern.ch/AccelConf/icalepcs2017/paper
@Misc{biblio:spdevices,
title = "ADQ7DC - Data Acquisition Unit - Digitizer: 14-bit, 10 GSPS digitizer platform, 1-2 channels",
howpublished = {\url{https://spdevices.com/products/hardware/14-bit-digitizers/adq7dc}},
}
@Misc{biblio:MIKES,
title = "VTT MIKES Metrology",
howpublished = {\url{ https://www.mikes.fi/ }},
}
@Misc{biblio:VSL,
title = "VSL",
howpublished = {\url{ }},
}
@Misc{biblio:LNE-SYRTE,
title = "LNE-SYRTE",
howpublished = {\url{ }},
}
@Misc{biblio:NLP,
title = "NLP",
howpublished = {\url{ }},
}
@Misc{biblio:NIST,
title = "NIST",
howpublished = {\url{ }},
}
@Misc{biblio:INRIM,
title = "INRIM",
howpublished = {\url{ }},
}
@Misc{biblio:KRIS,
title = "KRIS",
howpublished = {\url{ http://www.kriss.re.kr/eng}},
}
@Misc{biblio:WR-LJD,
title = "WRS Low Jitter Daugherboard",
howpublished = {\url{https://www.ohwr.org/projects/wrs-low-jitter/wiki/wiki}},
}
@ARTICLE{biblio:MIKES+VSL,
author={E. F. Dierikx and A. E. Wallin and T. Fordell and J. Myyry and P. Koponen and M. Merimaa and T. J. Pinkert and J. C. J. Koelemeij and H. Z. Peek and R. Smets},
journal={IEEE Transactions on Ultrasonics, Ferroelectrics, and Frequency Control},
title={White Rabbit Precision Time Protocol on Long-Distance Fiber Links},
year={2016},
volume={63},
number={7},
pages={945-952},
keywords={Global Positioning System;clocks;local area networks;optical fibre communication;protocols;time measurement;GPS precise point positioning;bidirectional paths;chromatic dispersion;delay asymmetry;distance 950 km;initial calibration;long-distance fiber links;synchronous Ethernet optical fiber networks;time transfer;white rabbit precision time protocol;Clocks;Delays;Optical fiber networks;Optical fibers;Optical switches;Synchronization;Clocks;White Rabbit;optical fiber networks;precision time protocol (PTP);time dissemination;timing},
doi={10.1109/TUFFC.2016.2518122},
ISSN={0885-3010},
month={July},}
@inproceedings{biblio:MIKES-50km,
author = "Anders Wallin and Mattia Rizzi and Guifré Molera Calvés and Thomas Fordell and Jyri Näränen",
title = "{Improved Systematic and Random Errors for Long-Distance Time-Transfer Using PTP White Rabbit }",
booktitle = "{32nd European Frequency and Time Forum 2018}",
year = "2018",
}
http://www.epapers.org/eftf2018/ESR/paper_details.php?PHPSESSID=t03vf3ur1ksr5rafkq24fe8k64&paper_id=7160
@INPROCEEDINGS{biblio:SYRTE-LNE-25km,
author={N. Kaur and P. Tuckey and P. E. Pottie},
booktitle={2016 European Frequency and Time Forum (EFTF)},
title={Time transfer over a White Rabbit network},
year={2016},
volume={},
number={},
pages={1-4},
keywords={frequency standards;optical fibre networks;time measurement;transfer standards;Allan deviation;LNE-SYRTE;White Rabbit network;frequency dissemination;long haul telecommunication network;optical fiber spool;time dissemination;time transfer;Chromatic dispersion;Optical fiber dispersion;Optical fiber networks;Rabbits;Time measurement;Time-frequency analysis;Wavelength division multiplexing;Chromatic dispersion;Long haul time and frequency dissemination;White Rabbit},
doi={10.1109/EFTF.2016.7477793},
ISSN={},
month={April},}
@INPROCEEDINGS{biblio:SYRTE-LNE-500km,
author={N. Kaur and F. Frank and P. E. Pottie and P. Tuckey},
booktitle={2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF/IFCS)},
title={Time and frequency transfer over a 500 km cascaded White Rabbit network},
year={2017},
volume={},
number={},
pages={86-90},
keywords={atomic clocks;data acquisition;optical fibre communication;synchronisation;White Rabbit link;active telecommunication networks;cascaded White Rabbit network;commercial White Rabbit equipment;distance 500.0 km;frequency dissemination;frequency transfer stability;integration time;long distance optical fiber links;software parameters;time transfer stability;unidirectional link setup;Clocks;Optical switches;Rabbits;Temperature measurement;Thermal stability;Time-frequency analysis},
doi={10.1109/FCS.2017.8088808},
ISSN={},
month={July},}
@inproceedings{biblio:WR-ultimate-limits,
author = "Rizzi, Mattia and Lipinski, Maciej and Ferrari, Paolo and Rinaldi, Stefano and Flammini, Alessandra",
title = "{White Rabbit clock synchronization: ultimate limits on close-in phase noise and short-term stability due to FPGA implementation}",
booktitle = "{Transactions on Ultrasonics, Ferroelectrics, and Frequency Control}",
year = "2018",
}
@Misc{biblio:WR-LJD-switch,
title = "ASTERICS: PRODUCTION OF ULTRA-LOW-NOISE WHITE RABBIT SWITCHES",
howpublished = {\url{https://www.asterics2020.eu/article/production-ultra-low-noise-white-rabbit-switches}},
}
@Misc{biblio:optical-amplifier,
title = "OPNT's quasi bidirectional optical amplifiers",
howpublished = {\url{http://www.opnt.nl/\#timing}},
}
@inproceedings{biblio:WR-NIST,
author = "J. Savory and J. Sherman and S. Romisch",
title = "{White Rabbit-Based Time Distribution at NIST}",
booktitle = "{IEEE International Frequency Control Symposium 2018}",
year = "2018",
}
@Misc{biblio:wr-sfps,
title = " SFP transceiver and fibre type to use for White Rabbit",
howpublished = {\url{https://www.ohwr.org/projects/white-rabbit/wiki/SFP}},
}
@inproceedings{biblio:WR-INRIM,
author = "G. Fantino and G. Cerretto and R. Costa and D. Calonico",
title = "{White Rabbit Time Transfer on Medium and Long Fibre Hauls at INRIM}",
booktitle = "{Proceedings of the 46th Annual Precise Time and Time Interval Systems and Applications Meeting}",
year = "2014",
}
@Misc{biblio:WR-INRIM-400km,
title = "WR-based time transfer between INRIM and Milano",
howpublished = {\url{https://www.top-ix.org/en/2018/03/22/the-time-as-service-service-becomes-operational/}},
}
\ No newline at end of file
papers/ISPCS2018/wrApplicationsOverview.tex
View file @ 91793574
......@@ -132,7 +132,7 @@ IEEE1588 standard and conclude in Section~\ref{sec:conclusions}
\label{sec:wrElements}
WR network elements are openly available on the Open Hardware Repository
(OHWR) \cite{biblio:OHWR} and available off-the-shelf from companies, see Figure~\ref{fig:WRN}.
(OHWR) \cite{biblio:OHWR} and available off-the-shelf from companies. %, see Figure~\ref{fig:WRN}.
While all of the WR networks use the same design of
WR switch \cite{biblio:wr-switch},
the design of WR nodes depends on application. Thus, WR node design is available
......@@ -152,13 +152,13 @@ Such a variety of WR nodes facilitaties
implementations of WR applications described in the following sections
\begin{figure}[!ht]
\centering
\vspace{0.1cm}
\includegraphics[width=0.45\textwidth]{misc/zoo-v2.jpg}
\caption{White Rabbit Network.}
\label{fig:WRN}
\end{figure}
% \begin{figure}[!ht]
% \centering
% \vspace{0.1cm}
% \includegraphics[width=0.45\textwidth]{misc/zoo-v2.jpg}
% \caption{White Rabbit Network.}
% \label{fig:WRN}
% \end{figure}
......@@ -178,39 +178,126 @@ implementations of WR applications described in the following sections
\section{Time and Frequency Transfer (TF)}
\label{sec:time-and-freq}
\subsection{Basic Concept}
The most basic application of WR is a transfer of time and/or frequency. The time
is provided as an output Pulse Per Second (PPS) signal and an information about the
number of seconds since the epoch. The frequency is provided as an output clock
signal (CLK) with the frequency of either 10 MHz or one of the WR base frequencies:
62.5MHz or 125MHz. The source of time and frequency in a WR network is the
Grandmaster (WR switch or node). Such Grandmaster is usually connected to a Cesium
or Rubidium frequency standard and Global Positionig System (GPS), thus providing
International Atomic Time (TAI) and frequency traceable to a
standard, both transferred from the Grandmaster to all the WR switches and WR
Nodes. The PPS and CLK can be provided to applications by WR switches
(via front panel outputs) and WR node (via output signals of an FMC
\cite{biblio:fmc-dio-5cha}\cite{biblio:fmc-dio-del}) . All of WR applications are
based on the precise transfer of time and
frequency. Yet, in practice mostly national time laboratories
(see Section~\ref{sec:timelabs}) use these signals directly. Most of the applications benefit
from functionalities that are built using the transferred time and/or frequency.
Such functionalites are described in the following subsections.
The most basic application of WR is the transfer of time and frequency from the
Grandmaster WR switch/node (Grandmaster) to all other WR switches/nodes in
the WR network. WR ensures that the Pulse Per Second (PPS) outputs of all the
WR switches/nodes in the WR network are aligned to the PPS output of the
Grandmaster with sub-ns accuracy and picoseconds precision. WR switches and
nodes use and can output clock signal (e.g. 10MHz, 125MHz) that is traceable to that
of the Grandmaster.
In most applications, Grandmaster is connected to a clock reference. Typically,
it is a Cesium or Rubidium oscillator disciplined by a global
navigation satellite system (GNSS), e.g. Global Positionig System (GPS).
In such case, the time and frequency transferred by WR are traceable to
International Atomic Time (TAI).
Although all of WR applications are based on precise transfer of time and
frequency, most of these applications benefit from functionalities that are
built on top of it and described in the subsequent sections. For example, the
precise timestamping functionality (Section~\ref{sec:timestamping}) can be
either integrated into WR nodes or provided by external devices (e.g. digitizers)
synchronized using PPS \& 10MHz provided by WR.
\subsection{Example Applications}
Time and Frequency distribution for AD\\
Finland (MIKES)\\
Netherlands (VSL)\\
France (LNE-SYRTE)\\
UK (NLP)\\
Italy (INFRIM)\\
White Rabbit Industrial Timing Enhancement (WRITE))\\
\\
\\
\\
\\
\\
\\
Time and frequency transfer is used by National Time Laboratories to
disseminate official UTC time and compare clocks. Laboratories in
Finland (VTT MIKES \cite{biblio:MIKES}),
Netherlands (VSL \cite{biblio:VSL}),
France (LNE-SYRTE \cite{biblio:LNE-SYRTE}),
UK (NLP \cite{biblio:NLP}),
USA (NIST \cite{biblio:NIST}),
Italy (INRIM \cite{biblio:INRIM})
and South Korea (KRIS) have WR installations. MIKES and INRIM
use WR to provide their realization of UTC to clients, e.g. UTC(MIKE) over 50km
to Metsähovi Observatory \cite{biblio:MIKES-50km} for applications in geodesy (International GNSS Service,
Very-long-baseline interferometry and satellite laser ranging), UTC(INRIM) over
400km to financial district of Millano. NIST uses WR to distribute UTC(NIST)
within their campus. All
laboratories are studing WR with different types of fiber links and attempt to
increase its performance. These studies showed that the jitter of the off-the-shelf
WR switch is 1e-11 (similar to typical frequency counter e.g. Keysight 53230A)
and can be improved.This prompted development of the Low-Jitter Daughterboard (LJD)
\cite{biblio:WR-LJD} that improves 1e-12 performance of the WR switch without any
modifications to the WR-PTP Protocol, see
\cite{biblio:MIKES-50km}\cite{biblio:SYRTE-LNE-500km}\cite{biblio:WR-ultimate-limits}.
The improved WR Switches are now commercially available \cite{biblio:WR-LJD-switch}.
The results from time laboratories studies are summarized in Table~\ref{tab:timelabs}.
\begin{table}[!ht]
\caption{}
\centering
\scriptsize
\begin{tabular}{
| p{0.7cm} | p{0.75cm} | p{2.3cm} | p{0.5cm} | p{1.5cm} | c | } \hline
\textbf{Time} & \textbf{Link} & \textbf{Link } & \textbf{Time } & \textbf{Time} & \textbf{Ref} \\
\textbf{Lab} & \textbf{Len } & \textbf{Type } & \textbf{Error} & \textbf{Stability} & \textbf{} \\ \hline
VTT & 950km & unidir. in DWDM & $\pm$2ns & 20ps@1000s & \cite{biblio:MIKES+VSL} \\ \cline{2-6}
MIKES & 50km & bidir. on adjacent ITU DWDM channels & $<$1ns & ~2e-12@1s (*) & \cite{biblio:MIKES-50km} \\ \hline
VSL & 2x137km & bidir. on CWDM (1470\&1490nm)(\#) & $<$8ns & 10ps@1000s & \cite{biblio:MIKES+VSL} \\ \hline
& 25km & unidir. at 1541nm & 150ps & 1-2ps@1000s & \cite{biblio:SYRTE-LNE-25km} \\ \cline{2-6}
LNE- & 25km & bidir. at 1310\&1490nm & 150ps & 1-2ps@1000s & \cite{biblio:SYRTE-LNE-25km} \\ \cline{2-6}
SYRTE & 125km & unidir. in the C-band or close OSC & 2.5ns & 1ps@1s (**) & \cite{biblio:SYRTE-LNE-500km} \\ \cline{2-6}
& 4x125km & unidir. in the C-band or close OSC & 2.5ns & 5.5ps@1s (**) & \cite{biblio:SYRTE-LNE-500km} \\ \hline
NIST & $<$10km & bidir. standard WR (1210\&1490nm \cite{biblio:wr-sfps}) & below 200ps & 20ps@1s & \cite{biblio:WR-NIST} \\ \hline
NPL & & & & & \\ \hline
& 50km & bidir. in WDM & 800ps $\pm$56ps& & \cite{biblio:WR-INRIM} \\ \cline{2-6}
INRIM & 70k m & bidir. in WDM & 610ps $\pm$47ps& & \cite{biblio:WR-INRIM} \\ \cline{2-6}
& 400km & unidir. in DWDM & & & \cite{biblio:WR-INRIM-400km} \\ \hline
\multicolumn{6}{|l|}{WDM = Wavelength Division Multiplexing} \\
\multicolumn{6}{|l|}{DWDM = Dense Wavelength Division Multiplexing} \\
\multicolumn{6}{|l|}{CWDM = Coarse Wavelength Division Multiplexing} \\
\multicolumn{6}{|l|}{\#~ Dedicated and commercial quasi-bidirectional optical amplifiers are used \cite{biblio:optical-amplifier}} \\
\multicolumn{6}{|l|}{*~ Low Jitter Daughterboard was used to enhance performance \cite{biblio:WR-LJD} } \\
\multicolumn{6}{|l|}{** Input stage of the Grandmaster was improved, the bandwidth of } \\
\multicolumn{6}{|l|}{~~~~WR switches/node was increased to 70Hz, PTP message rate was increased } \\ \hline
\end{tabular}
\label{tab:timelabs}
\end{table}
At CERN, the General Machine Timing controller of the Antiproton Decelerator (AD)
is synchronized with WR link to a similar controller of the LHC Injection
Chain (LHC) that provides the beam also for AD. Such a WR link provides traceability
to UTC and it is used instead of a GPS receiver.
%
% MIKES operates a 950km WR link \cite{} over unidirectional paths in a dark channel
% of active Dense Wavelength Division Multiplexing (DWDM) network and and a 50km
% link using optical DWDM transceivers on adjacent ITU DWDM channels (optical carrier
% spacing 100 GHz). VSL operates a 137km link in an active telecommunication network
% on a Coarse Wavelength Division Multiplexing band. LNE-SYRTE uses 125km
% uni-directional fiber links and long range SFPs in the C-band or OSC channels close
% to the C-Band cascading 4 WR switches to provide synchronization over 500km.
%
% The link uses
% identical Small Form-factor Pluggables (SFPs) on ITU-T DWDM channel \#60 (196.00 THz).
% After initial calibration of link asymmetry using GPS, a time transfer error within
% $\pm$2 ns was measured over 4-month operation while the time stability was as
% low as 20 ps at 1000 seconds of integration time. MIKES operates also a link
% of 50km to provide UTC(MIKE) to Metsähovi Observatory. The link uses optical DWDM
% transceivers on adjacent ITU DWDM channels (optical carrier spacing 100 GHz).
% The link takes advantage of the recently developed Low Jitter Daughterboard (LJD)
% that enhances the performance of the WR Switch without any modifications to the
% WR-PTP protocol.The results show performance at the 1e-12 level (at 1s, with
% 0.5 Hz BW).
%
% Time and Frequency distribution for AD\\
% Finland (MIKES)\\
% Netherlands (VSL)\\
% France (LNE-SYRTE)\\
% UK (NLP)\\
% Italy (INFRIM)\\
% White Rabbit Industrial Timing Enhancement (WRITE))\\
% \\
% \\
% \\
% \\
% \\
% \\
\newpage
\section{Time-Triggered Control (TC)}
......
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