122 lines
3.3 KiB
TeX
122 lines
3.3 KiB
TeX
\documentclass[showdate=false]{beamer}
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\usepackage[british]{babel}
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\usepackage{amsmath}
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\usepackage{hyperref}
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\usepackage[backend=bibtex,style=trad-plain]{biblatex}
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\usepackage{graphicx}
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\graphicspath{{.}{../../figures/}}
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\addbibresource{../../../bibliotheca/bibliography.bib}
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% Disable Captions
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\setbeamertemplate{caption}{\raggedright\small\insertcaption\par}
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% Show Section overview at beginning of section
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%\AtBeginSection[]
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%{
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% \begin{frame}<beamer>{Table of Contents}
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% \tableofcontents[currentsection, currentsubsection, sectionstyle=show/shaded, subsectionstyle=hide]
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% \end{frame}
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%}
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% no to navigation, yes to frame numbering
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\beamertemplatenavigationsymbolsempty
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\setbeamerfont{page number in head/foot}{size=\normalsize}
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\setbeamertemplate{footline}[frame number]
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\title[Grand DU]{Channel delays in the Grand Digitizer}
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\date{May 31, 2022}
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\author{E.T. de Boone}
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\begin{document}
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\frame{\titlepage}
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\begin{frame}{Wireless time distribution}
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\begin{block}{Current Timing Methods}
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\begin{itemize}
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\item GNSS (online)
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\item Beacon (online/offline)
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\end{itemize}
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\end{block}
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\vspace{2em}
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\begin{itemize}
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\item GPS Accuracy $\leq 30 \mathrm{ns}$ for $95$\% time (often better)
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\item Total time accuracy in the order of 5 -- 10~ns
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\end{itemize}
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\vspace{2em}
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\begin{alertblock}{Grand Digitizer Unit}
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\begin{itemize}
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\item Both GNSS and Beacon,
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\item Maybe test GNSS with Beacon?
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\end{itemize}
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\end{alertblock}
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\end{frame}
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\section{Channel Delays in the GRAND DU}
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\begin{frame}{Grand DU before ADC}
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\begin{columns}
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\begin{column}{0.5\textwidth}
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\begin{block}{GRAND Digitizer Unit}
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\begin{itemize}
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\item Four channel ADC
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\item Per-channel Filterchain (might introduce delays)
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\end{itemize}
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\end{block}
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\end{column}
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\begin{column}{0.5\textwidth}
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\begin{figure}
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\includegraphics[width=1\textwidth]{grand/setup/antenna-to-adc.pdf}
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\caption{
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Antennae to the four-channel ADC
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}
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\end{figure}
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\end{column}
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\end{columns}
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\end{frame}
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\begin{frame}{Channel Delays Setup}
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\begin{block}{Channel Delay Setup}
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Single input into two channels
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$\mapsto$ delays due to cabling and filterchain
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\\
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Use correlation or phase differences to determine delay
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\end{block}
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\only<1>{\begin{figure}
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\includegraphics[width=0.8\textwidth]{grand/setup/channel-delay-setup.pdf}
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\caption{Single input to two channels}
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\end{figure}}
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\only<2>{\begin{block}{What signal to put in?}
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\begin{itemize}
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\item Sine $\mapsto$ single frequency response of chain
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\item Pulse $\mapsto$ multiple frequencies to compare
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\end{itemize}
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\end{block}}
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\end{frame}
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\begin{frame}{Channel Delays Result I: Sine}
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\begin{block}{Sine ch1 ch2}
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Length difference: $1.16m \sim 4ns$ delay
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\\
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@50MHz: delay(ch1, ch2) = $46\mathrm{ps} \pm 10$
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\end{block}
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\begin{figure}
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\includegraphics[width=\textwidth]{grand/split-cable/split-cable-delay-ch1ch2-50mhz-200mVpp.pdf}
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%\caption{"@50MHz:
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%$5.643614156919462 \pm 0.010333456331688352$,
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%$-5.598005556921079 \pm 0.012115559927114126$
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% }
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\end{figure}
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\end{frame}
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\begin{frame}{Channel Delays Result II: Pulse}
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\begin{block}{Pulse ch1 ch2}
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Length difference: $1.16m \sim 4ns$ delay
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\end{block}
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\begin{figure}
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\includegraphics[width=\textwidth]{grand/split-cable/split-cable-delays-ch1ch4.pdf}
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\end{figure}
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\end{frame}
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%%%%%%%%%%%%%
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\end{document}
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