From 0e53c270dad353f10531039f55beea9672fc2480 Mon Sep 17 00:00:00 2001 From: Eric Teunis de Boone Date: Tue, 31 Oct 2023 15:19:29 +0100 Subject: [PATCH] Thesis: Conclusion: finished --- documents/thesis/chapters/conclusion.tex | 30 ++++++++++++++---------- 1 file changed, 18 insertions(+), 12 deletions(-) diff --git a/documents/thesis/chapters/conclusion.tex b/documents/thesis/chapters/conclusion.tex index 9754953..95c641d 100644 --- a/documents/thesis/chapters/conclusion.tex +++ b/documents/thesis/chapters/conclusion.tex @@ -1,3 +1,4 @@ +% vim: fdm=marker fmr=<<<,>>> \documentclass[../thesis.tex]{subfiles} \graphicspath{ @@ -10,34 +11,39 @@ \chapter{Conclusion} \label{sec:conclusion} +%<<< Using radio antennas to detect \glspl{UHECR} has received much attention recently. The \acrlong{Auger} is currently being upgraded to \gls{AugerPrime} incorporating radio detectors with scintillators and water-cherenkov detectors. Other experiments, such as \gls{GRAND}, plan\Todo{word} to fully rely on radio detection only. \\ % Timing not enough Time information in such large observatories is typically distributed using \glspl{GNSS}, reaching up to $10\ns$ accuracy under very good conditions. -For analysis using radio interferometry to be competitive, this timing accuracy needs to be improved towards the $1\ns$ (see Figure~\ref{fig:}). +For analysis using radio interferometry to be competitive, this timing accuracy needs to be improved towards the $1\ns$ mark. \\ +%>>> -% Beacon introduction +% Beacon introduction %<<< A viable method to obtain this timing accuracy is to incorporate a beacon transmitter into the array. -This (narrow-band) transmitter sends out a special\Todo{word} signal that is picked up by the radio antennas in the array. -With relatively simple techniques, the timing accuracy can be improved to below $1\ns$ (see Figures~\ref{fig:},~\ref{fig:}). +This (narrow-band) transmitter sends out a special signal that is picked up by the radio antennas in the array. +With relatively simple techniques, the timing accuracy can be improved to below $1\ns$. Thus, at a relatively low cost, the (relative) timing of radio arrays can be improved to enable radio interferometry. \\ +%>>> -% +% Passive Beacon %<<< In some circumstances, an external transmitter can be used as a beacon. -For example, in \gls{Auger}, a public TV broadcaster emits its signal at $f = 62.75\MHz$ from \Todo{name} (approximately $75\;\mathrm{km}$ north-west of the array\Todo{verify}). -With the source location and the frequency known, time delays can be calculated and this signal can be used to remove\Todo{word} timing errors smaller than $T = 1/f \sim 16\ns$. -Unfortunately, with the \gls{GNSS} timing accuracy estimated in the same order of magnitude and the signal being periodic, the synchronisation of the antennas can be off by an integer amount of periods $T$.\Todo{rewrite} +For example, in \gls{Auger}, a public TV broadcaster emits its signal at $f = 62.75\MHz$. +With the source location and the frequency known, time delays can be calculated and this signal can be used to account for timing errors smaller than $T = 1/f \sim 16\ns$. +Unfortunately, with the \gls{GNSS} timing accuracy estimated in the same order of magnitude and the signal being periodic, the synchronisation of the antennas can be off by an integer amount of periods $T$. \\ +% >>> +% Combined sine beacon + air shower %<<< Recording an air shower, in addition to such a narrow-band beacon, might provide a method to determine the correct beacon period. Radio interferometeric analysis of the air shower depends on the coherence of the received signals. -Any synchronicity problems in the radio antennas decrease the observed power of the reconstructed air shower. -With a limited set of periods to try\Todo{word}, this power can be maximised \Todo{word} while simultaneously determining the correct beacon period. +Any synchronicity problems in the radio antennas decrease the coherence and thus the power mapping used to derive properties of the air shower. +With a limited set of periods to test, this power can be maximised while simultaneously inferring the correct beacon period. \\ - - +The developed method to synchronise can be directly tested at \gls{Auger}, both with data from \gls{AERA} and the upcoming radio detectors from AugerPrime. +% >>> \end{document}