Add new plots to sampling mesh monitor chapter

chapter-sampling-mesh-monitor/chapter.tex

@@ -753,7 +753,47 @@ its switching happens in the short period between its input differential voltage
 combined forward voltage of the Schottky diodes. Thus, while the \partno{74LVC} might produce slow edges overall, its
 large output swing results in a high slew rate in the critical region around the zero crossing.
 
-We observed the best result overall with the \partno{PI3HDX12211} redriver, resulting in a rise time of
+\begin{figure}
+    \begin{center}
+        \begin{subfigure}{0.45\textwidth}
+            \centering
+            \includegraphics[width=\textwidth]{edge_sampling_pulse_scope.pdf}
+            \vspace*{-5mm}
+            \caption{Sampling pulse}
+            \label{fig_osc_risetime_samp}
+        \end{subfigure}
+        \unskip\begin{subfigure}{0.45\textwidth}
+            \centering
+            \includegraphics[width=\textwidth]{edge_stimulus_pulse_scope_normalized.pdf}
+            \vspace*{-5mm}
+            \caption{Stimulus pulse}
+            \label{fig_osc_risetime_stim}
+        \end{subfigure}
+    \end{center}
+    \vspace*{-5mm}
+    \caption[Pulse risetime oscilloscope measurements]{Oscilloscope measurements of the sampling pulse probed
+        differentially (left) and of the stimulus pulse probed single-ended and normalized (right). The 74LVC pulse is
+        plotted on the right Y axis in the left plot due to its large amplitude. In the right plot, it is not shown
+        since our measurement setup did not allow for a measurement of this amplitude.}
+    \label{fig_osc_risetime}
+\end{figure}
+
+Figure~\ref{fig_osc_risetime} shows the sampling and stimulus pulse edges measured using a Siglent SDS7404A
+\qty{4}{\giga\hertz} oscilloscope. The stimulus pulse was directly measured single-ended, and the sampaling pulse was
+measured differentially through a Siglent SAP2500D \qty{2.5}{\giga\hertz} active differential probe. These measurements
+support the conclusion from Figure~\ref{fig_spec_risetime} that in raw edge risetime, \partno{MAX3748} and
+\partno{TDP0604} perform fastest, with \partno{PI3HDX12211} being slightly slower. They also exhibit the large
+differences in amplitude that we expect cause the differences in actual measurement performance as shwon in
+Figure~\ref{fig_edge_risetime}. Note that due to the differences in measurement methodology, a direct comparison of the
+rise times is not possible between these plots. The spectrum measurements do not convey amplitude information and
+discard low-frequency content, but due to the very large bandwidth of the spectrum analyzer used, they will represent
+the true risetime the closest. In both the self-characterization and the oscilloscope measurements, the displayed
+risetime is contaminated by the measurement system. In case of the self-characterization, the stimmulus rise time is
+folded into the measurement result, leading in the displayed risetime being slower by a factor of $\sqrt{2}$. Similarly,
+in the oscilloscope measurements, the combined risetime of the oscilloscope frontend and active probe contaminate the
+results.
+
+We observed the best overall performance with the \partno{PI3HDX12211} redriver, resulting in a rise time of
 \qty{264}{\pico\second}. In this test specimen, we fed the pulse through the amplifier twice since we had two unused
 channels, and we used \qty{200}{\pico\second} clip lines on the amplifier's output for pulse shaping. We only used clip
 lines here and for \partno{TDP0604} since the other amplifiers' output did not contain sufficient harmonic content.

chapter-sampling-mesh-monitor/figures/sampling-mesh-monitor

@@ -1 +1 @@
-Subproject commit b4dc58286d039b1d0f70ea86f9e1f2cc538d8fbb
+Subproject commit cd33cff0e8b3284f26a4b87c9c9d40ae226dceed