mirror of
https://gitlab.science.ru.nl/mthesis-edeboone/m.internship-documentation.git
synced 2024-11-22 15:03:35 +01:00
Thesis: introduce vim markers into beacon chapter
This commit is contained in:
parent
c3e6e79003
commit
5ee21ea2da
1 changed files with 27 additions and 28 deletions
|
@ -1,5 +1,7 @@
|
|||
% vim: fdm=marker fmr=<<<,>>>
|
||||
\documentclass[../thesis.tex]{subfiles}
|
||||
|
||||
% Local preamble <<<
|
||||
\graphicspath{
|
||||
{.}
|
||||
{../../figures/}
|
||||
|
@ -32,9 +34,10 @@
|
|||
\newcommand{\pProp}{\pTrue_d}
|
||||
\newcommand{\pClock}{\pTrue_c}
|
||||
|
||||
% >>> Local Preamble
|
||||
|
||||
\begin{document}
|
||||
\chapter{Disciplining by Beacon}
|
||||
\chapter{Disciplining by Beacon} %<<<
|
||||
\label{sec:disciplining}
|
||||
Time synchronisation for autonomous stations is typically performed with a \gls{GNSS} clock in each station.
|
||||
The time accuracy supplied by the \gls{GNSS} clock ($\sim 10 \ns$) is not enough to do effective interferometry.
|
||||
|
@ -58,8 +61,7 @@ This influences the tradeoff between methods.
|
|||
In the following, the synchronisation scheme for both the continuous and intermittent beacon are elaborated upon.
|
||||
\Todo{further outline}
|
||||
|
||||
|
||||
\section{Physical Setup}
|
||||
\section{Physical Setup} %<<<
|
||||
|
||||
\begin{figure}
|
||||
\centering
|
||||
|
@ -178,11 +180,10 @@ The nature of the beacon allows for different methods to determine $(\tMeasArriv
|
|||
In the following, two approaches for measuring $(\tMeasArriv)_i$ are examined.
|
||||
\Todo{reword towards next sections?}
|
||||
|
||||
|
||||
%%%%
|
||||
%%%% >>>
|
||||
%%%% Pulse
|
||||
%%%%
|
||||
\section{Intermittent Pulse Beacon}
|
||||
\section{Intermittent Pulse Beacon}% <<<
|
||||
\label{sec:beacon:pulse}
|
||||
If the stability of the clock allows for it, the synchronisation can be performed during a discrete period.
|
||||
The tradeoff between the gained accuracy and the timescale between synchronisation periods allows for a dead time of the detectors during synchronisation.
|
||||
|
@ -293,13 +294,10 @@ Since the filtered signal is sampled discretely, this means the start of the
|
|||
|
||||
% dead time
|
||||
|
||||
|
||||
|
||||
|
||||
%%%%
|
||||
%%%% >>>
|
||||
%%%% Sine
|
||||
%%%%
|
||||
\section{Continuous Sine Beacon}
|
||||
\section{Continuous Sine Beacon}% <<<
|
||||
\label{sec:beacon:sine}
|
||||
% continuous -> can be discrete
|
||||
In the case that the stations need continuous synchronisation, a different route must be taken.
|
||||
|
@ -374,7 +372,7 @@ Later, a mechanism to lift the period degeneracy using an airshower as discrete
|
|||
|
||||
%%
|
||||
%% Phase measurement
|
||||
\subsection{Phase measurement}
|
||||
\subsection{Phase measurement}% <<<
|
||||
A continuous beacon can syntonise an array of antennas by correcting for the measured difference in beacon phases $(\Delta \pMeasArriv)_{ij}$.
|
||||
They are derived by applying a \gls{FT} to the traces of each antenna.
|
||||
|
||||
|
@ -417,9 +415,9 @@ These aspects are examined in the following section.
|
|||
}
|
||||
\label{fig:beacon:ttl_sine_beacon}
|
||||
\end{figure}
|
||||
|
||||
% >>>
|
||||
% DTFT
|
||||
\subsubsection{Discrete Time Fourier Transform}
|
||||
\subsubsection{Discrete Time Fourier Transform}% <<<
|
||||
% FFT common knowledge ..
|
||||
The typical \gls{FT} to obtain spectral information from periodic data is the \gls{FFT} (a fast implementation of the \gls{DFT} \eqref{eq:fourier:dft}).
|
||||
Such an algorithm efficiently finds the magnitudes and phases within a trace $x$ at specific frequencies $f = f_s \tfrac{k}{N}$ determined solely by the number of samples $N$ ($0 \leq k < N$) and the sampling frequency $f_s$.
|
||||
|
@ -485,9 +483,9 @@ With a constant beacon frequency, the coefficients for evaluating the \gls{DTFT}
|
|||
|
||||
% Removing the beacon from the signal trace
|
||||
|
||||
|
||||
% >>>
|
||||
% Signal to noise
|
||||
\subsubsection{Signal to Noise}
|
||||
\subsubsection{Signal to Noise}% <<<
|
||||
|
||||
% Gaussian noise
|
||||
The traces will contain noise from various sources, both internal (e.g. LNA) and external (e.g. radio communications) to the detector.
|
||||
|
@ -587,20 +585,22 @@ Phase distribution: gaussian
|
|||
\label{fig:time_res_vs_snr}
|
||||
\end{figure}
|
||||
|
||||
% Signal to Noise >>>
|
||||
|
||||
|
||||
|
||||
|
||||
\subsection{Period degeneracy}
|
||||
\subsection{Period degeneracy}% <<<
|
||||
% period multiplicity/degeneracy
|
||||
|
||||
% airshower gives t0
|
||||
|
||||
|
||||
|
||||
% Period Degeneracy >>>
|
||||
|
||||
% Continuous Sine Beacon >>>
|
||||
% >>>
|
||||
|
||||
\bigskip
|
||||
\section{Old work on Sine Beacon}
|
||||
\chapter{Old work on Sine Beacon}% <<<
|
||||
\Todo{fully rewrite}
|
||||
The idea of a sine beacon is semi-analogous to an oscillator in electronic circuits.
|
||||
A periodic signal is sent out from a transmitter (the oscillator), and captured by an antenna (the chip the oscillator drives).
|
||||
|
@ -681,17 +681,14 @@ This slower timescale allows to count the ticks of the quicker signal.\todo{Exte
|
|||
\end{figure}
|
||||
|
||||
|
||||
|
||||
|
||||
|
||||
\subsection{Beacons in Airshower timing}
|
||||
\subsection{Beacons in Airshower timing}% <<<
|
||||
To setup a time synchronising system for airshower measurements, actually only the high frequency part of the beacon must be employed.
|
||||
The low frequency part, from which the number of oscillations of the high frequency part are counted, is supplied by the very airshower that is measured.
|
||||
|
||||
|
||||
% >>>
|
||||
|
||||
|
||||
\section{Beacon synchronisation}
|
||||
\section{Beacon synchronisation}% <<<
|
||||
|
||||
As outlined in Section~\ref{sec:time:beacon}, a beacon can also be employed to synchronise the stations.
|
||||
|
||||
|
@ -768,7 +765,7 @@ However, while in a static setup the value of $k$ can be estimated from the dist
|
|||
\\
|
||||
|
||||
|
||||
\subsection{Lifting period degeneracy}
|
||||
\subsection{Lifting period degeneracy}% <<<
|
||||
\begin{figure}
|
||||
\begin{subfigure}[t]{0.5\textwidth}
|
||||
\includegraphics[width=\textwidth]{radio_interferometry/dc_grid_power_time_fixes.py.X400.no_offset.scale4d.pdf}
|
||||
|
@ -795,7 +792,9 @@ However, while in a static setup the value of $k$ can be estimated from the dist
|
|||
\label{fig:grid_power_time_fixes}
|
||||
\end{figure}
|
||||
|
||||
% >>>
|
||||
|
||||
|
||||
|
||||
%>>>
|
||||
\end{document}
|
||||
|
|
Loading…
Reference in a new issue