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-rw-r--r--vorlagen/thesis/src/kapitel_x.tex58
1 files changed, 35 insertions, 23 deletions
diff --git a/vorlagen/thesis/src/kapitel_x.tex b/vorlagen/thesis/src/kapitel_x.tex
index aa08a4a..d173620 100644
--- a/vorlagen/thesis/src/kapitel_x.tex
+++ b/vorlagen/thesis/src/kapitel_x.tex
@@ -389,7 +389,7 @@ user's position.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.60]{img/NAV-Message.pdf}
- \caption{One frame of 1500 bits on L1 frequency carrier}
+ \caption{One frame of 1500 bits on L1 frequency carrier. Image courtesy of \citep{harper2010server-side}.}
\label{img:gpsframe}
\end{figure}
Each subframe can be divided into three fields of data,
@@ -494,7 +494,7 @@ $(1500 \, \mathrm{bits per frame}\, \cdot \, 25 \, \mathrm{frames}) / (50 \,\mat
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/GPS-Modulation.pdf}
- \caption{Modulation of the GPS signal L1}
+ \caption{Modulation of the GPS signal L1. Image courtesy of \citep{harper2010server-side}.}
\label{img:gpsmod}
\end{figure}
@@ -759,7 +759,7 @@ in figure \ref{img:multCAPhase}.
phase not, in this case the phase is shifted for $\pi$, then
$d_{C/A}$ is inverted (second figure).
If the phase shifts with time, then the amplitude and phase of $d_{C/A}$
- shall vary as well (third figure).}
+ shall vary as well (third figure). Image courtesy of \citep{diggelen2009a-gps}.}
\label{img:multCAPhase}
\end{figure}
@@ -785,7 +785,7 @@ section \ref{sec:Carrierdemod}.
\centering
\includegraphics[scale=0.50]{img/PRN-ChipRate.pdf}
\caption{Comparison between the original C/A code generated on the
- GPS satellite with two synthesized PRN codes with a different phase shift on the receiver.}
+ GPS satellite with two synthesized PRN codes with a different phase shift on the receiver. Image courtesy of \citep{understandGPS}.}
\label{img:prnCodeCompare}
\end{figure}
For the particular example, the matching phase shift was achieved with
@@ -827,7 +827,7 @@ $+5=(+1)\cdot(+1)+(-1)\cdot(-1)+(+1)\cdot(+1)+(+1)\cdot(+1)+(-1)\cdot(-1)$.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/Correlation.pdf}
- \caption{Cross-correlation on three different signals}
+ \caption{Cross-correlation on three different signals. Image courtesy of \citep{understandGPS}.}
\label{img:correlatingSignals}
\end{figure}
The same principle applies to the transmitted C/A and
@@ -913,7 +913,7 @@ unknown frequency to be in range of $10 \, \mathrm{kHz}-25 \, \mathrm{kHz}$.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.70]{img/2D-SearchSpaceInk.pdf}
- \caption{Segment of the frequency/code delay search space for a single GPS satellite}
+ \caption{Segment of the frequency/code delay search space for a single GPS satellite. Image courtesy of \citep{diggelen2009a-gps}.}
\label{img:prnSearchSpace3d}
\end{figure}
@@ -974,7 +974,7 @@ in figure \ref{img:SearchSpace2d}.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/2DSearchSpace.pdf}
- \caption{The total search space}
+ \caption{The total search space.}
\label{img:SearchSpace2d}
\end{figure}
@@ -990,7 +990,7 @@ first time the GPS receiver is turned on. It is known under the name of cold sta
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/frequencySearch.pdf}
- \caption{Idea of the frequency searching algorithm}
+ \caption{Idea of the frequency searching algorithm.}
\label{img:freqSearch}
\end{figure}
@@ -1025,7 +1025,7 @@ known location.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/Localization.pdf}
- \caption{Basic distance estimation principle for one satellite}
+ \caption{Basic distance estimation principle for one satellite. Image courtesy of \citep{understandGPS}.}
\label{img:SatLocalization}
\end{figure}
In figure \ref{img:SatLocalization}, an example concept can be seen, where $\vec{u}=(x_u,y_u,z_u)$ represents the unknown
@@ -1051,7 +1051,7 @@ geometric distance $r$ is computed, as given in equation \eqref{eq:rDist}.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/TimingLoc.pdf}
- \caption{Estimating the distance by phase shift $\Delta t =t_2 - t_1 =\tau$}
+ \caption{Estimating the distance by phase shift $\Delta t =t_2 - t_1 =\tau$. Image courtesy of \citep{understandGPS}.}
\label{img:TimingLoc}
\end{figure}
\begin{equation}
@@ -1425,7 +1425,8 @@ GSM1800&1710 - 1785&1805 - 1880& 512 - 885\\\bottomrule
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/GSMUpDownFreq.pdf}
- \caption{Frequency ranges of uplink and downlink channels in the GSM900 band. Each box represents a frequency band (channel).}
+ \caption{Frequency ranges of uplink and downlink channels in the GSM900 band. Each box represents a frequency band (channel).
+ Image courtesy of \citep{konrad} and \citep{dennis}.}
\label{img:GSMFreqRangChannel}
\end{figure}
\par Aside from using different frequency channels, each frequency channel is split up into eight time slots.
@@ -1452,7 +1453,7 @@ without disturbing users on different time slots.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/GSMFreqTime.pdf}
- \caption{Each frequency channel is split into 8 time slots. More GSM users can be served at the ``same'' time.}
+ \caption{Each frequency channel is split into 8 time slots. More GSM users can be served at the ``same'' time. Image courtesy of \citep{0890064717}.}
\label{img:GSMFreqTime}
\end{figure}
@@ -1467,7 +1468,7 @@ SCH channels \citep[Chapter 4]{0470030704}.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.70]{img/GSMHierarchy.pdf}
- \caption{Hierarchy of the GSM frames.}
+ \caption{Hierarchy of the GSM frames. Image courtesy of \citep{0890064717}.}
\label{img:GSMHierarchy}
\end{figure}
@@ -1486,7 +1487,7 @@ was defined due to internal synchronization of the GSM network and cyphering bet
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/GSMBig.pdf}
- \caption{Basic GSM network block diagram.}
+ \caption{Basic GSM network block diagram. Image courtesy of \citep{konrad} and \citep{dennis}.}
\label{img:GSMBig}
\end{figure}
\label{sec:GSMNetStruct}
@@ -1618,7 +1619,7 @@ radio link control messages (signal strength and synchronization data) on the SA
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/SDCCHRequest.pdf}
- \caption{Initializing an successful SDCCH channel..}
+ \caption{Initializing an successful SDCCH channel. Image courtesy of \citep{0470844574}.}
\label{img:SDCCHReq}
\end{figure}
@@ -1671,7 +1672,8 @@ connected to the GSM network.}.
\centering
\includegraphics[scale=0.50]{img/RRLPRequest.pdf}
\caption{RRLP Request protocol. Assistance data can be sent before the request is made. If the assistance
- data are sent, their reception acknowledgement is sent as a response from the MS.}
+ data are sent, their reception acknowledgement is sent as a response from the MS.
+ Image courtesy of \citep{harper2010server-side} and \citep{04.31V8.18.0}.}
\label{img:RRLPReqProt}
\end{figure}
@@ -1918,7 +1920,7 @@ folowing section \ref{sec:rrlpassistance} more details of how assistance data ar
\centering
\includegraphics[scale=0.80]{img/RRLPReqExplained.pdf}
\caption{An example RRLP request. Constructing a binary RRLP request in PER from ASN.1. Yellow zero bits
- are extension markers or spare bits. }
+ are extension markers or spare bits. Image courtesy of \citep{harper2010server-side}.}
\label{img:RRLPReqExplained}
\end{figure}
@@ -2076,13 +2078,13 @@ Longitude is encoded as second compliment binary number \citep{3gppequations}.
\centering
\includegraphics[scale=0.5]{img/ElipsoidPoint.pdf}
\caption{Reference location is a 14 octet stream built according to the given rule as
- specified in the standard \citep{3gppequations} under section \textit{7.3.6}.}
+ specified in the standard \citep{3gppequations} under section \textit{7.3.6}. Image courtesy of \citep{3gppequations}.}
\label{img:refLocStandard}
\end{figure}
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.5]{img/EarthElipsoid.pdf}
- \caption{World Geodetic System 1984}
+ \caption{World Geodetic System 1984. Image courtesy of \citep{harper2010server-side}.}
\label{img:earthElipsoid}
\end{figure}
The altitude is encoded as it is where one bit increments represent one meter incerements.
@@ -3150,7 +3152,7 @@ database but notices by the author.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.38]{img/googlemapsResults.pdf}
- \caption{Test rooms as well as the results delivered by the smart phones.}
+ \caption{Test rooms as well as the results delivered by the smart phones. Image courtesy of Google Maps.}
\label{img:googlemapsResults}
\end{figure}
@@ -3406,9 +3408,9 @@ be connected into a path and displayed where the GSM user spends his time. Along
described method, a machine learning algorithm could be developed to predict the
movement of GSM users \citep{predictMovements}.
-Tests could be performed if it possible if it can be tricked out by the software Dennis mentioned (protect my privacy)!
+%Tests could be performed if it possible if it can be tricked out by the software Dennis mentioned (protect my privacy)!
-\chapter{Summary and security issues}
+\chapter{Summary and discussion}
This thesis has investigated how difficult it is to integrate mobile assisted GPS localization in GSM
Networks. The aim of this work was set out to implement the ``first'' working open source RRLP
implementation in GSM networks, as well as to determine and evaluate the limits of this localization
@@ -3424,7 +3426,17 @@ consideration no information are sent to the GSM user and is a gray area from th
\citep{silentPolice1}. "The state found that it was not one, since there is no content. This is useful,
because if it is not a communication, it does not fall under the framework of the inviolability of
telecommunications described in Article 10 of the German Constitution." said Mathias Monroy from
-Heise Online \citep{silentPolice1}.
+Heise Online \citep{silentPolice1}. The development of a working RRLP application and obtained
+results from this work enhance the understanding of AGPS receivers and may be further used to
+better understand how the assistance data influence the obtained results.
+Finally, a number of important limitations in the obtained results need to be considered.
+Not all assistance data were available and the tests have been performed at different time points of the day.
+The amount of tested cell phones was not representative enough. However, this work has thrown up some
+questions in need of further investigation but it is only a tip of the iceberg! A future study
+investigating if further assistance data are provided to the cell phones would be very interesting.
+The produced RRLP software and obtained results may be used to develop new strategies aimed at
+protecting privacy of cell phone users.
+