\documentclass[showdate=false]{beamer} \usepackage[british]{babel} \usepackage{amsmath} \usepackage{hyperref} \usepackage[backend=bibtex,style=trad-plain]{biblatex} \usepackage{graphicx} \graphicspath{{.}{../../figures/}} \addbibresource{../../../bibliotheca/bibliography.bib} %%%%%% % Disable Captions %%%%% \setbeamertemplate{caption}{\raggedright\small\insertcaption\par} \newcommand\blfootnote[1]{% \begingroup \renewcommand\thefootnote{}\footnote{#1}% \addtocounter{footnote}{-1}% \endgroup } %\addtobeamertemplate{navigation symbols}{}{% % \usebeamerfont{footline}% % \usebeamercolor[fg]{footline}% % \hspace{1em}% % \insertframenumber %} %%%%%%%% Outline %%%%%%%% % % - Timing Mechanisms % % - White Rabbit % % - Fourier and Phase information % % \title[Timing Accuracy]{Timing Accuracy in Air Shower Detectors} \date{February 03, 2022} \author{E.T. de Boone} \begin{document} \frame{\titlepage} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Timing Mechanisms in Detectors} \begin{frame}{Timing Mechanisms} {Timing Mechanisms} \begin{itemize} \item GNSS (online) \item Beacon (offline) \end{itemize} \vspace{2em} \begin{itemize} \item More accurate reference timing needed to characterise/improve current mechanisms. \end{itemize} \end{frame} %%%%%%%%%%%%% \begin{frame}{Timing Mechanisms: GNSS} \begin{block}{} \begin{itemize} \item Accuracy $\sim 5 ns$ \end{itemize} \end{block} \end{frame} %%%%%%%%%%%%% \begin{frame}{Timing Mechanisms: Beacon} \begin{itemize} \item Beating between frequency signals indicate timing \item PA: located in physics band $\mapsto$ offline analysis, \\ corrects for GPS drift. \item different frequency responses for antenna models \end{itemize} \begin{columns} \begin{column}{.5\textwidth} \begin{figure} \includegraphics[width=\textwidth]{beacon/auger/1512.02216.figure2.beacon_beat.png} \caption{Four beacon frequencies create a well-defined beating. From \cite{PierreAuger:2015aqe}} \end{figure} \end{column} \begin{column}{.5\textwidth} \begin{figure} \includegraphics[width=\textwidth]{beacon/auger/1512.02216.figure4.ads-b.png} \caption{Automatic Dependent Surveillance Broadcasts (ADS-B) intercepts. From \cite{PierreAuger:2015aqe}} \end{figure} \end{column} \end{columns} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Experimental Setup: White Rabbit} \begin{frame}{Precision Time Protocol} \begin{itemize} \item Time synchronisation over (long) distance between (multiple) nodes \end{itemize} \begin{figure} \includegraphics[width=0.4\textwidth]{white-rabbit/protocol/ptpMSGs-color.pdf} \caption{Precision Time Protocol messages. From \cite{WRPTP}}. \end{figure} \end{frame} %%%%%%%%%%%%% \begin{frame}{White Rabbit} \begin{columns} \begin{column}{.5\textwidth} White Rabbit: \begin{itemize} \item SyncE ($f=125\textrm{MHz}$) (shared oscillator) \item PTP (synchronisation) \end{itemize} \vspace{2em} Factors: \begin{itemize} \item device ($\Delta_{txm}$, $\Delta_{rxs}$, ...) \item link ($\delta_{ms}$, ...) \end{itemize} \begin{figure} \makebox[\textwidth][c]{\includegraphics[width=1.2\textwidth]{white-rabbit/protocol/delaymodel.pdf}} %\caption{From \cite{WRPTP}}. \end{figure} \end{column} \begin{column}{.5\textwidth} \begin{figure} \makebox[\textwidth][c]{\includegraphics[width=1.1\textwidth]{white-rabbit/protocol/wrptpMSGs_1.pdf}} \caption{From \cite{WRPTP}}. \end{figure} \end{column} \end{columns} \end{frame} %%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%% \section{Fourier and Phase information} \begin{frame}{Discrete Fourier and Phase} \begin{block}{} \begin{equation*} u(t) = \exp(2i\pi ft + \phi_t) \end{equation*} \begin{equation*} N_{required} := f_{sample\_rate} / f_{signal} \end{equation*} \end{block} \includegraphics[width=\textwidth]{fourier/02-fourier_phase-f_max_showcase.pdf} \end{frame} %%%%%%%%%%%%% \begin{frame}{Phase reconstruction??} \begin{block}{} \begin{equation*} u(t) = \exp(2i\pi ft + \phi_t) \end{equation*} \end{block} \begin{figure} \makebox[\textwidth][c]{\includegraphics[width=1.4\textwidth]{fourier/02-fourier_phase-phi_f_vs_phi_t.pdf}}% \end{figure} \begin{block}{} Phase reconstruction is easy if sample rate ``correct'' \end{block} \end{frame} %%%%%%%%%%%%% \begin{frame}{Phase reconstruction??} \begin{block}{} What if sample rate ``incorrect''? \end{block} \begin{figure} \makebox[\textwidth][c]{\includegraphics[width=1.4\textwidth]{fourier/02-fourier_phase-phi_f_vs_f_max_increasing_N_samples.pdf}}% \end{figure} \end{frame} %%%%%%%%%%%%% \begin{frame}{Phase reconstruction??} \begin{block}{} What if sample rate ``incorrect''? \\ Linear interpolation ({\small $f_\mathrm{max}$, $f_\mathrm{submax}$, $\phi_\mathrm{max}$ and $\phi_\mathrm{submax}$}) \end{block} \begin{figure} \makebox[\textwidth][c]{ \includegraphics[width=\textwidth]{fourier/02-fourier_phase-phase_reconstruction-unfolded.pdf} } \end{figure} \end{frame} %%%%%%%%%%%%% \begin{frame}{} \begin{block}{} \begin{equation*} A_1 / A_2 \end{equation*} \end{block} \begin{figure} \makebox[\textwidth][c]{\includegraphics[width=1.4\textwidth]{fourier/02-fourier_phase-relative_amplitudes_vs_N_samples.pdf}}% \end{figure} \end{frame} \end{document}