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diff --git a/vorlagen/thesis/src/kapitel_x.tex b/vorlagen/thesis/src/kapitel_x.tex
index c4d2711..eb8bec9 100644
--- a/vorlagen/thesis/src/kapitel_x.tex
+++ b/vorlagen/thesis/src/kapitel_x.tex
@@ -2680,7 +2680,7 @@ configuration the power supply port is not used. The following port is for the e
connection with 48 V DC power supply. This port is connected to a power supply
that is supplied with the nanoBTS. It extends the ethernet connection with 48 V DC
for the normal operation mode of the nanoBTS which is in the range between 38-50 V DC.
-The power consumtion of the nanoBTS is 13 W. More details on how to interconnect the cables
+The power consumption of the nanoBTS is 13 W. More details on how to interconnect the cables
shall be given in section \ref{sec:hardwareConfig}. In the middle of the five port region,
the mini USB port can be found. It is used by the manufacturer to write the firmware software
to the nanoBTS. The last two ports are the TIB-IN and TIB-OUT port\footnote{TIB stands
@@ -2825,9 +2825,9 @@ were obtained. Analysis of the results by the time required to perform a
localization of a GSM user and the geographical dislocation error using
Google maps are going to be discussed. Smart phones used
for the test are going to be introduced and followed by the location
-of the tests. After the results have been presented,
+of the tests. After the results have been provided,
a section with criticism demonstrates all the obstacles that may have appeared
-while the tests have been performed and why some of the results may biased. The criticism
+while the tests have been performed and why some of the results may be biased. The criticism
section is a vital part of this thesis, aside from the given theoretical and
mathematical perspective of how AGPS works and why lack of time synchronization inside
GSM can be of critical value to correctly evaluate the results. It gives an additional
@@ -2880,7 +2880,12 @@ first only an RRLP request without any
assistance data was sent. The second test included an RRLP request with almanac, UTC model, ionospheric model and
reference location data. The last test was an RRLP request with almanac, ephemeris, UTC model,
ionospheric model and reference location data. The stated requests have been sent in an
-reverse order, to observe if the smart phones can actually make an usage of the assistance data.
+reverse order, to observe if the smart phones can actually make an usage of the assistance data.
+The RRLP requests were manually sent from the telnet interface from OpenBSC after they have been
+implemented by the author. Results delivered by the MS were stored in the database and the
+following analysis is based on them and on the time out results which were not stored in the
+database but notices by the author.
+
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.38]{img/googlemapsResults.pdf}
@@ -2909,6 +2914,28 @@ $G1$ may not know how to employ the ephemeris data because it is one of the firs
market. Later on it can be seen other smart phones that are even older than the $G1$ can not employ any of the
assistance data.
+\begin{figure}
+ ~ %add desired spacing between images, e. g. ~, \quad, \qquad etc.
+ %(or a blank line to force the subfigure onto a new line)
+ \centering
+ \begin{subfigure}[b]{0.3\textwidth}
+ \centering
+ \includegraphics[width=\textwidth]{img/smartPhoneWindow.jpg}
+ \caption{Smart phones on the window.}
+ \label{fig:window}
+ \end{subfigure}
+ ~ %add desired spacing between images, e. g. ~, \quad, \qquad etc.
+ %(or a blank line to force the subfigure onto a new line)
+ \begin{subfigure}[b]{0.3\textwidth}
+ \centering
+ \includegraphics[width=\textwidth]{img/smartRoomTable.jpg}
+ \caption{Smart phones on the table.}
+ \label{fig:table}
+ \end{subfigure}
+ \caption{Test room 2 with the positions of the smart phones}\label{fig:animals}
+ \label{img:smartphonepositions}
+\end{figure}
+
The second tests took place in Test room 2. Test room 2 is located in the basement of the
computer pool, with the following coordinates: latitude 48\textdegree 0'13.12"N and
longitude 7\textdegree 50'53.50"E. The fact tests took place in the basement adds
@@ -2936,18 +2963,12 @@ The majority of the performed tests in this work were performed in this room.
Smart phones have been tested on the table which is $3 m$ away from the windows
and on the window itself, as shown in figure \ref{img:smartphonepositions}.
These small changes in position of the smart phone did not make any difference
-in the resulting estimated position. To find out if the delivered
-results are taken from the cache or some other memory in the
-smart phone, the same test have been performed in the basement hallway where no
-windows exist just after the smart phones delivered successfully their position
-in Test room 2. This test did not deliver any position but only time outs
-or errors. This test provided and confirmed that the smart phones are always
-performing a postion estimation at the moment when an RRLP request is sent
-to the MS. The smart phones tested in Test room 2 were all the listed ones
-in table \ref{tbl:smartphones}. One unanticipated finding was that
-the ``newer generation'' smart phones did not deliver their
-position in any case but rather requested more assistance data like $iPhone$ $4$,
-$Galaxy$ $S2$ and $Galaxy$ $S3$. There are two possible explanations for this result.
+in the resulting estimated position. The smart phones tested in Test
+room 2 were all the listed ones in table \ref{tbl:smartphones}. One
+unanticipated finding was that the ``newer generation'' smart phones did not
+deliver their position in any case but rather requested more assistance data
+like $iPhone$ $4$, $Galaxy$ $S2$ and $Galaxy$ $S3$. There are two possible
+explanations for this result.
This might be because the newer AGPS devices require more assistance data
by relying on the network providers to have synchronized GSM systems or it is an
security protection of the smart phone user. No information on the AGPS receiver
@@ -2963,67 +2984,123 @@ the tests. At the time point when they were released by Nokia the firmware for t
might not have been fully evolved and developed since both models are from the
same company.
+The third test took place in Test room 3, as shown in figure \ref{img:googlemapsResults}
+by the yellow dot. The smart phones were placed on the windows.
+In this room the smart phones tested did not deliver any positions but only errors about
+missing assistance data and time outs. While no MS delivered its position, the room was
+tested if a GPS position can be obtained with an external GPS receiver.
+The test was successful and after 12 minutes the position was obtained but the signal
+strength was weak according to the delivered GPS output. An implication emerging from
+this finding may be related to the GPS receiver high sensitivity (-160 dBm $10^{−16}$ mW)
+and an active patch antenna with a size of 2x2 cm \citep{ubxDatasheet}.
+The GPS receivers employed in smart phones have to be small in size to fit into the device
+and use a passive antenna because active antennas have an additional power consumption
+\citep{gpsAntenna}.
+
+To determine if the delivered results are taken from the cache or some other memory in the
+smart phone, the same test have been performed in the basement hallway where no
+windows exist just after the smart phones delivered successfully their position
+in Test room 2. This test did not deliver any position but only time outs
+or errors containing information that no satellites are visible.
+This test provided and confirmed that the smart phones are always performing a
+postion estimation at the moment when an RRLP request is sent to the MS.
+
+The last test has been performed outside of the computer pool building.
+This test was conducted to confirm the argument that precision of the estimated
+position is related to the received GPS signal strength and number of visible satellites.
+As it can be seen in figure \ref{img:googlemapsResults}, the tests were performed
+at the blue dot and around it and the estimated positions were 1-5 m off of
+the real position. The estimated positions are shown in a blue rectangle with an O
+in the left corner of it.
+\begin {table}[ht]
+\caption{Smart phone RRLP test results}
+\label{tbl:resultsByTest}\centering
+%\rowcolor{2}{light-gray}{}
+\scriptsize\fontfamily{iwona}\selectfont
+\begin{tabular}{lllll}
+\toprule
+%$D$&&$P_u$&$\sigma_N$\\
+Cell phone model&RRLP(E)&RRLP(A)&RRLP&Type of error (or missing data)\\\toprule
+$Defy$&No&No&No&No response (time out) \\\midrule
+$iPhone$ $4$&No&No&No&Reference time, Navigation Model,\\
+&&&&Reference Location\\\midrule
+$iPhone$ $3GS$&Yes&Yes&No&/\\\midrule
+$G1$&No&Yes&Sometimes&/\\\midrule
+$Galaxy$ $S2$&No&No&No&Acquisition Assistance\\\midrule
+$Galaxy$ $S3$&No&No&No&Reference Location, Reference Time,\\
+&&&&Acquisition Assistance, Navigation Model\\\midrule
+$Galaxy$ $Nexus$ $i9250$&No&No&No&Did not respond, only ACKs\\\midrule
+$E71$&No&No&Yes&/\\\midrule
+$N95$&No&No&Yes&/\\\midrule
+$Desire$ $S$&Yes&No&No&/\\\midrule
+$Blade$&No&No&Yes&/
+\\\bottomrule
+\end {tabular}
+\end {table}
+In table \ref{tbl:resultsByTest} the list of all results is shown. The abbreviations
+used in the table are explained in this paragraph. RRLP indicates the MS has delivered its
+position only when an RRLP position request without any assistance data has been sent.
+RRLP(E) indicates the MS has delivered its position only when an RRLP request contained
+almanac, ephemeris, UTC model, ionospheric model and reference location data has been sent.
+RRLP(A) indicated the MS has delivered its position only when an RRLP request contained
+almanac, UTC model, ionospheric model and reference location data has been sent (the difference
+from RRLP(E) is in the fact that no ephemeris data are included). If there is no error description
+then the stated data were requested to be delivered to the MS. If the position was delivered the
+position estimation by the smart phones took never longet than 3 minutes. The waiting time period
+of 3 minutes for the result is not discouraging provided that the assistance data like
+reference time (exact time, explained in section \ref{sec:rrlpassistance}) and
+acquisition assistance data (phase and Doppler effect frequency required by the AGPS,
+explained in section \ref{sec:rrlpassistance}) were not delivered to the MS. It is important
+to mention the strange behaviour by $Galaxy$ $Nexus$ $i9250$, the MS responded only with
+acknowledgements while the assistance data have been sent but after the reception it
+immediatelly closed the SDCCH channel. The $Blade$ closed the SDCCH channel after 4 transmitted
+assistance packets for the RRLP(E) test. The $Defy$ by Motorola did not produce any output at
+all and behaved like a 2G cell phone without a GPS receiver. To eliminate any doubts and
+suspicion if the SDCCH channel was properly working and not producing the time outs,
+2G phones (Nokia 3310 and Siemens M50) have been used to perform tests. An SDCCH channel
+has been initialized 10 times at different days with the 2G phones and left open for 10
+minutes. The 2G phones reported the signal strengths of the initialized channel according
+to the defined standard. This provides a proof for the cases where the time out appeared,
+it was not produced by the BTS but rather by the smart phone. One important remark related
+to the tests ought to be mentioned. While the $iPhone$ $3GS$ and $G1$ provided the results in
+the tests, sometimes it was the case they did not deliver the results the first time
+the RRLP request was executed but an time out. Second time the same RRLP request was sent,
+the smart phones delivered their positions. This unexpected behaviour raises a suspicion that
+the smart phones do not behave according to the RRLP standard where it is well defined how much
+time they have to perform the localization. However, the previous statement ought to be considered
+with some uncertainty since it can not be proved without access to the firmware of the smart phones.
+The combination of described findings in this chapter and in table \ref{tbl:resultsByTest}
+provides some support for the premise that the RRLP standard is not yet a fully implemented
+standard by all the manufacturers that claim AGPS functionality. Does it dependt on the AGPS chipset
+or RRLP itself, remains an open question.
-\begin{figure}
- ~ %add desired spacing between images, e. g. ~, \quad, \qquad etc.
- %(or a blank line to force the subfigure onto a new line)
- \centering
- \begin{subfigure}[b]{0.3\textwidth}
- \centering
- \includegraphics[width=\textwidth]{img/smartPhoneWindow.jpg}
- \caption{Smart phones on the window.}
- \label{fig:window}
- \end{subfigure}
- ~ %add desired spacing between images, e. g. ~, \quad, \qquad etc.
- %(or a blank line to force the subfigure onto a new line)
- \begin{subfigure}[b]{0.3\textwidth}
- \centering
- \includegraphics[width=\textwidth]{img/smartRoomTable.jpg}
- \caption{Smart phones on the table.}
- \label{fig:table}
- \end{subfigure}
- \caption{Test room 2 with the positions of the smart phones}\label{fig:animals}
- \label{img:smartphonepositions}
-\end{figure}
-
-Comparing the two results, it can be seen that
-
-Motorola Defy Nothing
-Samsung Galaxy S2 H
-Nokia E71
-Nokia N95 4810 error
-iPhone 4 D,G,F
-iPhone 3GS
-Google phone G1
-HTC Desire S
-ZTE Blade
-Samsung Galaxy S3
-Samsung Galaxy Nexus i9250
-
-\newpage
\section{Criticism of performed tests}
Perhaps the most serious weakness of the presented results
is that the author had no access to the firmware of the MS while the
tests have been performed. This would allow the author to see what type
and how the assistance data are employed by the AGPS in the MS. If access
could be gained, to the internal operation of the AGPS receiver,
-all bias could be eliminated whether the AGPS receiver uses the transmitted
-assistance data or it may be the case that they are from the memory in the
-smart phones. The whole system represents a black box where an input is
+all doubts and bias about the deduced hypotheses could be eliminated.
+The whole system represents a black box where an input is
delivered and an output is expected. Another drawback was the lack of
-the hardware information inside the MS. This does not allow an exact
-comparison between different cell phone models.
-
+hardware information about the hardware inside of the MS (AGPS receivers and
+antennas). This does not allow an exact comparison between different
+cell phone models and if they can acquire any GPS signal in weak signal
+strength conditions.
Difficulties arise in assessment and comparing the results in this
-thesis with other relevant studies due to the lack of expensive
-hardware equipment used in the studies. In addition, no research has
-been found that surveyed the amount of time required to get a
-position response from a MS where only almanac, ephemeris, UTC model,
-ionospheric model and reference location data have been delivered to
-the MS.
+thesis with other relevant studies due to the lack of any research
+studies compleyed using the equivalent hardware and type of
+assistance data. In the relevant studies different
+hardware test equipment is used while this thesis was carried
+out without that test equipment \citep{agpsTests} \citep{agpsTests1}
+\citep{gpsTest2}.
+In addition, no research has been found that surveyed the amount of
+time required to get a position response from a MS where only
+almanac, ephemeris, UTC model, ionospheric model and reference
+location data have been delivered to the MS.
Another limitation of the evaluated results lies in the fact that it has
only been applied to the stated cell phones and it could not be tested
@@ -3033,18 +3110,37 @@ rather in serial manner in time. In other words a satellite visible at
the moment while the first test is being performed may not be visible
the second time when the test is executed. GPS signal strength is a vital
measurement information, where the signal levels are lower than a
-predefined acquisition sensitivity even assistance data can not always help.
+predefined acquisition sensitivity even assistance data can not help.
Antenna polarization and the position of the cell phone matter as well.
Correctness of assistance data in almanac and ephemeris data can not be
verified. The author had to rely and trust NASA and Trimble as sources
although errors were confirmed by different studies in \citep{Stanford-Ephem-Errors}
\citep{NASA-Ephem-Errors}. Errors can be confirmed by the author in
-ephemeris data as well (URA values were out of range specified by the standard).
+ephemeris data as well (URA values were out of range specified by the standard).
+These errors were not continual but appeared occasionally and these errors
+were inside of the assistance data provided by NASA.
\section{Future work}
-
-Test if it can be tricked out by the software Dennis mentioned (protect my privacy)!
+The system could be extended with a GPS device that delivers raw GPS data
+instead of using the data provided by NASA and Trimble. Obtained data by the GPS
+could be compared to the data provided by NASA or other GPS observation stations
+and verified for errors. By having more redundant sources of same information,
+mistakes in the output could be eliminated. More sources of redundant data could
+indicate the correctness of assistance data.
+
+Another idea to extend this work would be to use an LMU and provide the
+reference time and acquisition assistance data. This feature would enhance the
+complete system. However, one ought to understand it would require great changes
+in the OpenBSC source code and interoperability between the BTS and LMU.
+
+Additionally a position tracking system could be built. By adding a timer that will
+execute an RRLP request every few minutes. The successfully estimated positions could
+be connected into a path and displayed where the GSM user spends his time. Along the
+described method, a machine learning algorithm could be developed to predict the
+movement of GSM users \citep{predictMovements}.
+
+%Test if it can be tricked out by the software Dennis mentioned (protect my privacy)!
\chapter{Summary}