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Thesis: beacon: whitespace removal + parentheses around \Delta
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1 changed files with 17 additions and 17 deletions
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@ -95,9 +95,9 @@ If the time of emitting the signal at the transmitter $\tTrueEmit$ is known, thi
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\phantom{,}
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%$
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(\tTrueArriv)_i
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=
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=
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\tTrueEmit + (\tProp)_i
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=
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=
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(\tMeasArriv)_i - (\tClock)_i
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%$
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,
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@ -113,7 +113,7 @@ In that case, the differences between the true arrival times $(\tTrueArriv)_i$ a
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\label{eq:interantenna_t0}
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\phantom{.}
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\begin{aligned}
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\Delta (\tTrueArriv)_{ij}
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(\Delta \tTrueArriv)_{ij}
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&\equiv (\tTrueArriv)_i - (\tTrueArriv)_j \\
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&= \left[ \tTrueEmit + (\tProp)_i \right] - \left[ \tTrueEmit + (\tProp)_j \right] \\
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%&= \left[ \tTrueEmit - \tTrueEmit \right] + \left[ (\tProp)_i - (\tProp)_j \right] \\
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@ -159,10 +159,10 @@ This can be resolved by knowledge on the $\tTrueEmit$ of the transmitter.
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In general, we are interested in synchronising an array of antennas.
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As \eqref{eq:synchro_mismatch_clocks} applies for any two antennas in the array, all the antennas that record the signal can determine the synchronisation mismatches simultaneously.
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\\
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The mismatch terms for any two pairs of antennas sharing a single antenna $( (i,j), (j,k) )$ allows to find the closing mismatch term for $(i,k)$ since
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The mismatch terms for any two pairs of antennas sharing a single antenna $\{ (i,j), (j,k) \}$ allows to find the closing mismatch term for $(i,k)$ since
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\begin{equation*}
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\label{eq:synchro_closing}
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\Delta (\tClock)_{ij} + \Delta(\tClock)_{jk} + \Delta(\tClock)_{ki} = 0
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(\Delta \tClock)_{ij} + (\Delta \tClock)_{jk} + (\Delta \tClock)_{ki} = 0
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\end{equation*}
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Taking one antenna as the reference antenna with $(\tClock)_r = 0$, the mismatches across the array can be determined by applying \eqref{eq:synchro_mismatch_clocks} over consecutive pairs of antennas and thus all clock deviations $(\tClock)_i$.
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\\
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@ -233,7 +233,7 @@ The strength of the beacon at each antenna must therefore be tuned such to both
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% continuous -> period multiplicity
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The continuity of the beacon poses a different issue.
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Because the beacon must be periodic, differentiating between consecutive periods is not possible using the beacon alone.
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The $\tTrueEmit$ term describing the transmitter time in \eqref{eq:transmitter2antenna_t0} is no longer uniquely defined,
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The $\tTrueEmit$ term describing the transmitter time in \eqref{eq:transmitter2antenna_t0} is no longer uniquely defined,
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\begin{equation}
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\phantom{,}
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\label{eq:period_multiplicity}
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@ -242,7 +242,7 @@ The $\tTrueEmit$ term describing the transmitter time in \eqref{eq:transmitter2a
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\end{equation}
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with $-\pi < \pTrueEmit < \pi$ the phase of the beacon at time $\tTrueEmit$, $T$ the period of the beacon and $k \in \mathbb{Z}$.
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\\
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This changes the synchronisation mismatches in \eqref{eq:synchro_mismatch_clocks} to
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This changes the synchronisation mismatches in \eqref{eq:synchro_mismatch_clocks} to
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\begin{equation}
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\label{eq:synchro_mismatch_clocks_periodic}
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\phantom{.}
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@ -268,7 +268,7 @@ In AERA \cite{PierreAuger:2015aqe} for example, the total beacon repeats only af
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With an estimated accuracy of the \gls{GNSS} below $50 \ns$ the correct beacon period can be determined, resulting in a unique $\tTrueEmit$ transmit time\todo{reword}.
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\\
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% lifing period multiplicity -> short timescale counting +
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% lifing period multiplicity -> short timescale counting +
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Another scheme is using an additional discrete signal to declare a unique $\tTrueEmit$.
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This relies on the ability of counting how many beacon periods have passed since the discrete signal has been recorded.
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@ -296,7 +296,7 @@ Later, a mechanism to lift the period degeneracy using an airshower as discrete
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A continuous beacon can syntonise antennas by correcting for the measured difference in beacon phase $(\Delta \pMeasArriv)_{ij}$.
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The beacon phase can be derived from an antenna trace by applying a Fourier Transform to the data.
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\\
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The trace will contain noise from various sources external and internal to the detector such as
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The trace will contain noise from various sources external and internal to the detector such as
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\begin{figure}[h]
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\begin{subfigure}{0.45\textwidth}
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@ -359,10 +359,10 @@ Known phasor $\vec{s}$ + random phasor $\vec{m} = a e^{i\pTrue}$ with $-\pi < \p
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\begin{equation}
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\label{eq:phasor_pdf}
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p_{A\PTrue}(a, \pTrue; s, \sigma)
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p_{A\PTrue}(a, \pTrue; s, \sigma)
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= \frac{a}{2\pi\sigma^2}
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\exp[ -
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\frac{
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\exp[ -
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\frac{
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{\left( a \cos \pTrue - s \right)}^2
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+ {\left( a \sin \pTrue \right)}^2
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}{
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@ -376,21 +376,21 @@ requiring $ -\pi < 0 \leq pi $ and $a > 0$, otherwise $p_{A\PTrue} = 0$.
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Rician distribution ( 2D Gaussian at $\nu$ with $\sigma$ spread)
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\begin{equation}
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\label{eq:amplitude_pdf:rice}
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p^{\mathrm{RICE}}_A(a; s, \sigma)
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p^{\mathrm{RICE}}_A(a; s, \sigma)
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= \frac{a}{\sigma^2}
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\exp[-\frac{a^2 + s^2}{2\sigma^2}]
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\;
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I_0\left( \frac{a s}{\sigma^2} \right)
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\end{equation}
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with $I_0(z)$ the modified Bessel function of the first kind with order zero.
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No signal $\mapsto$ Rayleigh ($s = 0$);
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No signal $\mapsto$ Rayleigh ($s = 0$);
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Large signal $\mapsto$ Gaussian ($s \gg a$)
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\bigskip
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Rayleigh distribution
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\begin{equation}
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\label{eq:amplitude_pdf:rayleigh}
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p_A(a; s=0, \sigma)
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p_A(a; s=0, \sigma)
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= p^{\mathrm{RICE}}_A(a; \nu = 0, \sigma)
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= \frac{a}{\sigma^2} e^{-\frac{a^2}{2\sigma^2}}
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\end{equation}
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@ -408,7 +408,7 @@ Gaussian distribution
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Rician phase distribution: uniform (low $s$) + gaussian (high $s$)
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\begin{equation}
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\label{eq:phase_pdf:full}
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p_\PTrue(\pTrue; s, \sigma) =
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p_\PTrue(\pTrue; s, \sigma) =
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\frac{ e^{-\left(\frac{s^2}{2\sigma^2}\right)} }{ 2 \pi }
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+
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\sqrt{\frac{1}{2\pi}}
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@ -422,7 +422,7 @@ Rician phase distribution: uniform (low $s$) + gaussian (high $s$)
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with
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\begin{equation}
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\label{eq:erf}
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\erf{\left(z\right)} = \frac{2}{\sqrt{\pi}} \int_0^z \dif{t} e^{-t^2}
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\erf{\left(z\right)} = \frac{2}{\sqrt{\pi}} \int_0^z \dif{t} e^{-t^2}
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\end{equation}
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.
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