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authorRefik Hadzialic2012-08-06 18:00:25 +0200
committerRefik Hadzialic2012-08-06 18:00:25 +0200
commit0fec36e8e79b023c44fbe46d7d755f0ef9f00a5e (patch)
treedfc4594bdaec649b0a0c436caf8d699dd3df2855
parentRRLP Response (diff)
downloadmalign-0fec36e8e79b023c44fbe46d7d755f0ef9f00a5e.tar.gz
malign-0fec36e8e79b023c44fbe46d7d755f0ef9f00a5e.tar.xz
malign-0fec36e8e79b023c44fbe46d7d755f0ef9f00a5e.zip
Started implementation
-rw-r--r--vorlagen/thesis/maindoc.pdfbin6221890 -> 6228809 bytes
-rw-r--r--vorlagen/thesis/src/img/RRLPRequest.pdfbin8992 -> 8918 bytes
-rw-r--r--vorlagen/thesis/src/kapitel_x.tex287
-rw-r--r--vorlagen/thesis/src/maindoc.lof2
4 files changed, 175 insertions, 114 deletions
diff --git a/vorlagen/thesis/maindoc.pdf b/vorlagen/thesis/maindoc.pdf
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--- a/vorlagen/thesis/maindoc.pdf
+++ b/vorlagen/thesis/maindoc.pdf
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diff --git a/vorlagen/thesis/src/img/RRLPRequest.pdf b/vorlagen/thesis/src/img/RRLPRequest.pdf
index 8f523ca..280ee1a 100644
--- a/vorlagen/thesis/src/img/RRLPRequest.pdf
+++ b/vorlagen/thesis/src/img/RRLPRequest.pdf
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diff --git a/vorlagen/thesis/src/kapitel_x.tex b/vorlagen/thesis/src/kapitel_x.tex
index cbdc1fc..4000fef 100644
--- a/vorlagen/thesis/src/kapitel_x.tex
+++ b/vorlagen/thesis/src/kapitel_x.tex
@@ -12,7 +12,7 @@ in 2011 there were
6 billion mobile connections worldwide \citep{gsmConnection}. In the following European
countries, Germany, France, Spain, Italy and UK, 44\% of all GSM users own a smart phone,
whereas in the US and Canada this number is slightly higher, 46\% \citep{smartPhoneUsage}. By the
-statistics of the Blur group 47\% of all the cell phones on the world will be smart phones
+statistics of the Blur group 47\% of all the cell phones on the world shall be smart phones
by 2015 \citep{smartPhone2015}.
An emerging new market of location based services (LBS) have grown out of it and since then
@@ -25,8 +25,8 @@ It has been reported that LBS represent a bonanza opportunity for new startup
companies and Global Industry Analysts project by 2015 a global market
worth of \$21 USD billion ($\approx$ \euro17.142 billion) \citep{Bonanza}.
New ideas and algorithms for tracking,
-navigation solutions, safety, security, local business search and payments will emerge
-from it as well as the new market that will emerge from the results of data mining
+navigation solutions, safety, security, local business search and payments shall emerge
+from it as well as the new market that shall emerge from the results of data mining
user's movement \citep{Bonanza}. LBS have been used for tracking people with dementia, Alzheimer's
disease, as reported in a study performed by the University of Siegen \citep{Muller}.
The Enhanced 911 (E911), an emergency service in the US for linking
@@ -37,13 +37,13 @@ Similar standards exist for Europe's E112 service as well \citep{0849333490}. Ne
networks, long term evolution (LTE) 4G networks, have been designed from the start to have LBS capabilities integrated
in the system and even a better LBS performance as well as accuracy compared to GSM networks \citep{lteLocation}.
In the introductory chapter, some of the most known positioning techniques in
-wireless networks will be presented and analysed, Cell-ID, time of arrival, angle of
-arrival and GPS positioning. Then the author will proceed and describe the goals of his thesis.
+wireless networks shall be presented and analysed, Cell-ID, time of arrival, angle of
+arrival and GPS positioning. Then the author shall proceed and describe the goals of his thesis.
\newpage
\section{Positioning techniques}
-In this section related technologies for estimating the position of a mobile user will be presented
+In this section related technologies for estimating the position of a mobile user shall be presented
and their working principle.
When the GSM network was designed, its primary goal was to enable wireless
full duplex telephony service \citep{gsmTelephony}.
@@ -55,15 +55,15 @@ devolopment of different approaches that differ in complexity and in the degree
However, the user positioning was limited by using existing technology standards
without making extremely expensive cost modifications to the existing network infrastructures. With
regards to costs and existing infrastructure, different ideas have been developed to localize mobile users.
-They will be presented in the following sections but before the details are revealed it is important to
+They shall be presented in the following sections but before the details are revealed it is important to
distinguish three different approaches to positioning mobile user's, handset, network and hybrid-based
approach. The handset based techniques are based on one fact, the handset itself tries to estimate its
position using the available information on its own. In the network based approach the network makes
all the required measurements and the handset itself is passive. The last approach, hybrid based, uses
resources from the handset and network together, both are active participants in the position estimation process. In
the further text with mobile station the target user one wants to locate is ment. A few different methods,
-varying by their complexity and precision, will be presented. First simple and then more advanced techniques
-will be presented in their order.
+varying by their complexity and precision, shall be presented. First simple and then more advanced techniques
+shall be presented in their complexity order.
\subsection{Cell-ID}
Cell-identification method is the simplest known GSM ranging method \citep[Chapter 8]{0470092319}.
@@ -173,7 +173,7 @@ Using the observed time difference, the BTS's can compute the location of the MS
position estimation technique takes place while there is an active call on the MS or the BTS makes a silent call
to the MS where the mobile user is not aware of being tracked \citep{malik2009rtls}. This technique is slightly
less accure than E-OTD, the accuracy lies between 50-300 m \citep{200mRangeEOTD}. Both of these techniques are
-challenged by the nature of the GSM network due to its unsynchronized operation. One microsecond error will produce
+challenged by the nature of the GSM network due to its unsynchronized operation. One microsecond error shall produce
an error of around 300 m. The advantage of UL-TDOA over E-OTD lies in the fact that no extra software modifications
have to be made on the cell phone and this technique works on every cell phone. UL-TDOA is a network based position
estimation technique.
@@ -207,15 +207,15 @@ The theoretical foundation of how GPS and AGPS receivers estimate the position i
in more detail in chatper \ref{gpsTheoryChatper}.
This method does not work on every cell phone as the previously mentioned methods.
It requires the cell phones to be equiped with an AGPS receiver.
-From this point on, cell phones with an AGPS receiver will be refered as smart phones
-since they have another potential use besides the default communication application. The AGPS
+From this point on, cell phones with an AGPS receiver shall be refered as smart phones
+since they have another potential use aside from the default communication application. The AGPS
position estimation technique is a hybrid based technique because the position is estimated
with the help of the handset, that estimates the position, and the network provider since
it delivers the required data for faster acquisition time.
\subsection{Other techniques}
The earlier mentioned localization techniques are not the only existing methods but are the standardized ones.
-In this section, two more techniques will be briefly described, angle of arrival and Google maps WiFi tagging.
+In this section, two more techniques shall be briefly described, angle of arrival and Google maps WiFi tagging.
\begin{figure}[ht!]
\centering
\includegraphics[scale=1.20]{img/AOA.pdf}
@@ -231,7 +231,7 @@ The intersection point represents the location of the MS. The angle is derived b
signal transmitted from the MS and the time difference of arrival for different elements of the burst
signal. Once the angle is computed, it is straightforward to find the intersection point.
This technique requires the BTS's to be synchronized with LMU's and to be in line of sight with the BTS's,
-otherwise this method will develiver poor position results. It belongs to the group of network based
+otherwise this method shall develiver poor position results. It belongs to the group of network based
position estimation techniques.
\begin{figure}[ht!]
@@ -290,22 +290,22 @@ with WiFi& &with Google maps and& &with aid\\
\clearpage
\section{Goals of the thesis}
-In this thesis the author will give an attempt to provide theoretical and practical
+In this thesis the author shall give an attempt to provide theoretical and practical
background knowledge required for building a localization system inside of a 2G GSM network by
taking the advantage of cell phones with AGPS receivers.
-Theoretical knowledge of GPS and AGPS receivers will be provided,
+Theoretical knowledge of GPS and AGPS receivers shall be provided,
as well as of the GSM system. The theoretical concepts of GPS receivers
-will be analysed and discussed in profound depth
-since it will provide strong evidence on the advantages and limitations
-of this method. This will provide the correlation for the observed results.
+shall be analysed and discussed in profound depth
+since it shall provide strong evidence on the advantages and limitations
+of this method. This shall provide the correlation for the observed results.
-Once the GPS and GSM working principles have been explained, the author will proceed with introducing the reader
+Once the GPS and GSM working principles have been explained, the author shall proceed with introducing the reader
to the Radio Resource Location Protocol (RRLP), responsible for obtaining the location
and transmission of the assistance data to the cell phone.
%\footnote{RRLP can be seen as the connection point between the AGPS and GSM subsystems.}
-Furthermore, the reader will be introduced to
-the software development process and the hardware connection schemes will be provided.
+Furthermore, the reader shall be introduced to
+the software development process and the hardware connection schemes shall be provided.
In the last part of this thesis, test results are reported and summary of the entire system is presented.
@@ -332,7 +332,7 @@ the errors that can influence the overall working of the system.
-In this paragraph the general idea will be given how GPS works and how the position is estimated.
+In this paragraph the general idea shall be given of how GPS works and how the position is estimated.
Before all the details are revealed in the following sections,
it is important to understand the basic principle of GPS navigation.
GPS positioning works by using the principle of \textit{trilateration}.
@@ -351,8 +351,8 @@ The blue, yellow and green wireframes below the GPS satellites represent the sph
for a given range, between the satellite and the estimated position of the GPS user
for the given satellite.
By intersecting all the three spheres, the position of the user is estimated.
-In the next sections this general idea will be developed in more details,
-step by step, and the ideas will be verified using the appropriate mathematical
+In the next sections this general idea shall be developed in more details,
+in an step by step approach, and the ideas shall be verified using the appropriate mathematical
models.
\clearpage
@@ -392,14 +392,14 @@ The third segment of the subframe, indicated as rest of data in figure
\ref{img:gpssubframe}, consists of the navigation data. The first subframe
includes data about the satellite accuracy and health as well as parameters
used for the clock corrections on the receiver side. More details on these
-parameters will be given in section \ref{sec:SigDemod}. Subframe two and three
+parameters shall be given in section \ref{sec:SigDemod}. Subframe two and three
are made of \textit{ephemeris data}. Ephemeris
information are precise parameters for predicting the precise orbital
position of the GPS satellite. Using ephemeris data for the specific
system time stamp and the equations given in appendix section \ref{sec:gpsConsAndEq}
the GPS receiver can precisely estimate the position $(x_s,y_s,z_s)$ of
the satellite. The first three subframes are satellite dependent and do not
-change in the transmitted 25 frames beside the system time stamp \citep{GPS-Guide}.
+change in the transmitted 25 frames aside from the system time stamp \citep{GPS-Guide}.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.50]{img/GPSSubframe.pdf}
@@ -413,7 +413,7 @@ These low-precision parameters are used by the GPS receiver to estimate the roug
position of the GPS satellites and to reduce the searching space for the GPS satellite
transmission frequencies\footnote{Although all satellites transmit on the same one frequency,
when the signals are received on Earth, they have a different frequency
-from the transmitted one. This will be further explained in more details in the following sections \ref{sec:Carrierdemod},
+from the transmitted one. This shall be further explained in more details in the following sections \ref{sec:Carrierdemod},
\ref{sec:CAdemod} and \ref{sec:2dSearch}.} and
obtaining the precise ephemeris data.
Ionospheric model and UTC time calculation parameters are required
@@ -438,7 +438,7 @@ These signals travel an average distance of $20200 \, km$ from the satellite to
and are affected by various sources of noise. BPSK modulation is mostly used for satellite links
because of its simplicity and immunity to noise and signal intereference for the price of
transfering data at low speed rates \citep[Chapter 1]{9780849316579}. The demodulation process
-of L1 will be discussed and analysed seperately in section \ref{sec:Carrierdemod}.
+of L1 shall be discussed and analysed seperately in section \ref{sec:Carrierdemod}.
\begin{figure}[ht!]
\centering
@@ -471,7 +471,7 @@ than of the data \citep[Chapter 3]{bensky2008wireless}. Single bits in PRN seque
and the complete sequence as \textit{code} \citep[Chapter 3]{bensky2008wireless}. This newly generated
signal is called direct sequence spread spectrum (DSSS) \citep[Chapter 3]{bensky2008wireless}. In
GPS terminology it is named as Code/Acquisition (C/A) code. C/A code is feed into the BPSK modulation
-process, where it is mixed with the carrier wave and producing the L1 signal. More details will be given in the
+process, where it is mixed with the carrier wave and producing the L1 signal. More details shall be given in the
C/A demodulation section \ref{sec:CAdemod}. Transmission speed of the navigation message is
50 bps, therefore the reception of a complete masterframe requires around $\approx12.5$ minutes, i.e.
$(1500 \, \mathrm{bits per frame}\, \cdot \, 25 \, \mathrm{frames}) / (50 \,\mathrm{bps} \, \cdot \, 60\, \mathrm{s})$.
@@ -492,7 +492,7 @@ amplifier.
\label{eq:GPSSignalReceived1}
S(t) = PD(t)C(t)cos(2\pi f_{c}+\varphi_{GPS})
\end{equation}
-The equation \ref{eq:GPSSignalReceived1} will be rewritten as given in \ref{eq:GPSSignalReceived2}. It
+The equation \ref{eq:GPSSignalReceived1} shall be rewritten as given in \ref{eq:GPSSignalReceived2}. It
represents the same equation but at the GPS receiver after traveling $\approx 20200 \, km$, where $d_{C/A}$
is the C/A data and $n(t)$ is the random noise at moment $t$ influenced by various factors that influence
electromagnetic waves.
@@ -502,7 +502,7 @@ S(t) = \sqrt{\frac{P}{2}}d_{C/A}cos(2\pi f_{c}+\varphi_{GPS}) + n(t)
\end{equation}
The GPS satellites are positioned in orbits so that at every moment at any spot on Earth, at least four satellites are visible
(a spot can be considered as a mountain peak since in the cities GPS signals are blocked by buildings).
-In the next section, more details will be revealed on the process of demodulating the GPS L1 signal and acquiring the
+In the next section, more details shall be revealed on the process of demodulating the GPS L1 signal and acquiring the
correct time and position.
@@ -574,9 +574,9 @@ denoted as $t_{exact}$ and is given in equation \eqref{eq:exactTime}.
%estimate the distance from the satellite
%but is not sufficient to estimate the position of the GPS receiver.
Propagation time is computed by measuring the phase shift of the C/A
-signal, more details will be given in sections \ref{sec:CAdemod}
+signal, more details shall be given in sections \ref{sec:CAdemod}
and \ref{sec:distanceAndPosition}.
-More importantly, $t_{exact}$ time will be later used
+More importantly, $t_{exact}$ time shall be later used
to synchronize various time dependent systems like the
GSM, LTE, GNSS or other communication and ranging systems.
\begin{equation}
@@ -672,7 +672,7 @@ The reason for this is straightforward to understand by looking at the
the synthesized sine wave (multiplication is the function of
a mixer, denoted as $\otimes$ in figure \ref{img:L1Demod}).
For the purpose of easier analysis, cosine waves
-will be used istead of sine waves, the difference between them
+shall be used istead of sine waves, the difference between them
is only in the phase shift, as denoted in equation
\eqref{eq:sineEqCosine}.
\begin{equation}
@@ -726,10 +726,10 @@ with the DC term (zero frequency producing a constant voltage) leaving only $\fr
\Delta \omega = \omega_{1}-\omega_{2} = 0
\end{equation}
However, if the frequencies do not match, $f_{1}\neq f_{2}$,
-then the output signal $\frac{1}{2}d_{C/A}$ will be
+then the output signal $\frac{1}{2}d_{C/A}$ shall be
modified by the residual frequency $f_{1}-f_{2}$,
-and subsequently this will change the demodulated C/A output (also known as phase shift). Under those circumstances
-the correlator will be unable to match the C/A code with the
+and subsequently this shall change the demodulated C/A output (also known as phase shift). Under those circumstances
+the correlator shall be unable to match the C/A code with the
correct PRN code. An illustration of this phenomenon is depicted
in figure \ref{img:multCAPhase}.
@@ -744,7 +744,7 @@ 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 $d_{C/A}$
- will vary as well (third figure).}
+ shall vary as well (third figure).}
\label{img:multCAPhase}
\end{figure}
@@ -754,7 +754,7 @@ in figure \ref{img:multCAPhase}.
\label{sec:CAdemod}
As a result of the previous step, one can continue with
the demodulation of the C/A wave. Demodulating the C/A wave
-with the PRN code will result in the time and navigation data.
+with the PRN code shall result in the time and navigation data.
Each tracked GPS satellite signal is demodulated seperately
using the same PRN code, code chipping rate and carrier frequency-phase
(which was determined above) for the given satellite
@@ -847,13 +847,13 @@ Without the property given in \eqref{eq:prnIdealCaseZero},
the GPS receiver would not be able to smoothly
differentiate between different GPS satellite signals.
Once the phase shift, $\tau$, has been found, the C/A code is modulated
-(XORed) with it. The resulting binary code will be the navigation message.
-The implementation problem of finding correct C/A and carrier wave demodulation will be
+(XORed) with it. The resulting binary code shall be the navigation message.
+The implementation problem of finding correct C/A and carrier wave demodulation shall be
further explained in the following section \ref{sec:2dSearch}.
\subsection{Implementation of the 2D search space problem}
\label{sec:2dSearch}
-In the following paragraphs an introduction will be given on
+In the following paragraphs an introduction shall be given on
the implementation problems of the previously mentioned concepts.
As it can be seen,
from subsections \ref{sec:Carrierdemod} and
@@ -927,7 +927,7 @@ D_{F} = \left\vert \frac{\sin(\pi \Delta fT_{ci})}{\pi \Delta fT_{ci}} \right\ve
The frequency mimsmatch loss sinc function, $D_{F}$, is evaluated in dB,
therefore for a loss of $\approx 0.98 \,\mathrm{dB}$, the frequency mismatch ought to be
$\Delta f = 250\, \mathrm{Hz}$,
-due to the fact that the maximum loss will occur when the frequency is differing
+due to the fact that the maximum loss shall occur when the frequency is differing
by 1/2 of the bin spacing. That is to say, for a bin space of 500 Hz, it is 250 Hz.
``The total range of possible GPS code delays is $1\, ms$. This is because the GPS C/A
@@ -1096,8 +1096,8 @@ compared to linear equations.
There are different techniques to solve sets of nonlinear equations \citep[Chapter 7]{understandGPS}
but in this work the linearization method\footnote{Linear approximation is a technique where a function
is approximated using a linear function.}
-will be presented to find the unknown terms $(x_u,y_u,z_u,t_u)$, i.e. out of an approximate position and clock
-offset the true user position and the true clock offset will be calculated.
+shall be presented to find the unknown terms $(x_u,y_u,z_u,t_u)$, i.e. out of an approximate position and clock
+offset the true user position and the true clock offset shall be calculated.
\begin{equation}
\label{eq:rhoSatsNewFun}
\rho_i= \sqrt{(x_i-x_u)^2+(y_i-y_u)^2+(z_i-z_u)^2} + ct_u = f(x_u,y_u,z_u,t_u)
@@ -1113,7 +1113,7 @@ can be rewritten as an approximate pseudorange \eqref{eq:rhoSatsNewFunApprox}.
\hat{\rho_i}= \sqrt{(x_i-\hat{x_u})^2+(y_i-\hat{y_u})^2+(z_i-\hat{z_u})^2} + c\hat{t_u} = f(\hat{x_u},\hat{y_u},\hat{z_u},\hat{t_u})
\end{equation}
In other words, the unknown true position terms $x_u$, $y_u$, $z_u$ and the clock offset term $t_u$, of the GPS receiver,
-will be expressed by the approximate values and an incremental component as shown in equation \eqref{eq:userCoordinates} \citep{understandGPS}.
+shall be expressed by the approximate values and an incremental component as shown in equation \eqref{eq:userCoordinates} \citep{understandGPS}.
\begin{equation}
\label{eq:userCoordinates}
\begin{array}{l}
@@ -1129,12 +1129,12 @@ as in \eqref{eq:rhoSatsNewFunwithApprox}.
\label{eq:rhoSatsNewFunwithApprox}
f(x_u,y_u,z_u,t_u) = f(\hat{x_u}+\Delta x_u, \hat{y_u}+\Delta y_u, \hat{z_u}+\Delta z_,\hat{t_u}+\Delta t_u)
\end{equation}
-In the next step the pseudorange function will be approximated using Taylor series\footnote{Taylor
+In the next step the pseudorange function shall be approximated using Taylor series\footnote{Taylor
series ``is a representation of a
function as an infinite sum of terms that are calculated from the values of the function's
derivatives at a single point'' \citep[Chapter 11]{taylor}.} (linearization of the nonlinear equation). Taylor
series for a function $f(x)$ is given in equation \eqref{eq:taylor}, where as $a$ approches $x$ the estimation
-error will be smaller and smaller, i.e. $f(x) = f(a)$ when $x=a$. The approximation error
+error shall be smaller and smaller, i.e. $f(x) = f(a)$ when $x=a$. The approximation error
depends on Taylor polynomial degree (the amount of terms or taken derivatives of the function)
and how far away the point $a$ is from $x$ \citep[Chapter 11.9]{taylor}.
The basic idea of the principle can be seen in figure \ref{img:taylorSeries}.
@@ -1229,7 +1229,7 @@ the equation resembles the one given in \eqref{eq:userPosition}.
\Delta\rho_i = \alpha_{xi}\Delta x_u + \alpha_{yi}\Delta y_u + \alpha_{zi}\Delta z_u - c\Delta t_u
\end{equation}
There are four unknowns, $\Delta x_u$, $\Delta y_u$, $\Delta z_u$ and $\Delta t_u$, in equation \eqref{eq:userPosition}.
-By solving this set of linear equations, which will result in finding $\Delta x_u$, $\Delta y_u$, $\Delta z_u$ and $\Delta t_u$,
+By solving this set of linear equations, which shall result in finding $\Delta x_u$, $\Delta y_u$, $\Delta z_u$ and $\Delta t_u$,
the GPS receiver position $(x_u, y_u, z_u)$ and clock offset $t_u$ is computed by replacing the
same into equations in \eqref{eq:userCoordinates}. Equation \eqref{eq:userPosition} can be rewritten for four satellites
in the matrix form as in \eqref{eq:userPositionMatrix}.
@@ -1278,7 +1278,7 @@ to the just derived position values, that is, $\hat{x_u}=x_u$, $\hat{y_u}=y_u$,
$\hat{t_u}=t_u$. This process is repeated until the approximated positions converge to their final
values. It is not necessarily required that the initial positions are very accurate
and the results are usually obtained by 4-5 itterations \citep{pseudorangeError}.
-Risks exist that the solutions will still be corrupted but there are different error avoiding
+Risks exist that the solutions shall still be corrupted but there are different error avoiding
mechanisms to solve these problems, like minimizing the error contribution using more than four satellite
measurements \citep{pseudorangeError} \citep[Chapter 7]{understandGPS}.
@@ -1287,7 +1287,7 @@ measurements \citep{pseudorangeError} \citep[Chapter 7]{understandGPS}.
\newpage
\section{Assisted GPS in Wireless networks}
\label{sec:agps}
-In the following paragraphs Assisted GPS (AGPS) will be presented and how it works.
+In the following paragraphs Assisted GPS (AGPS) shall be presented and how it works.
AGPS receivers work on the equivalent idea as warm/hot start on GPS receivers.
Instead of loading the recently saved data from the EEPROM, an external
information transfer medium is used to deliver the equivalent type of information that are known
@@ -1325,10 +1325,10 @@ an antenna with a gain of $3\, \mathrm{dB}$ with respect to an isotropic (omnidi
\citep[Chapter 2]{diggelen2009a-gps}.} (located near ground) at worst normal orientation''
\citep{GPS-Interface-Specification}.
-A simplified AGPS algorithm given in \citep{springerlink:10.1007/s10291-002-0028-0} will be presented here. This
+A simplified AGPS algorithm given in \citep{springerlink:10.1007/s10291-002-0028-0} shall be presented here. This
algorithm benefits in speed the more assistance data is present. As the first satellites are tracked,
the AGPS algorithm has an estimation of the feasible region where the target AGPS user might be located.
-Consequently, this feasible region will shrink until the location has been fully estimated
+Consequently, this feasible region shall shrink until the location has been fully estimated
\citep{springerlink:10.1007/s10291-002-0028-0}.
\begin{enumerate}[(i)]
\item Visible satellites and their positions are identified and computed out of the delivered ephemeris
@@ -1358,8 +1358,8 @@ be present in the assistance data \citep{998892}.
\chapter{GSM}
\chapter{Radio Resource Location Protocol}
-This chapter will focus on the Radio Resource Location Protocol (RRLP) and a description
-how it works inside of the GSM network will be given. RRLP is a protocol from the family of Location Services (LCS)
+This chapter shall focus on the Radio Resource Location Protocol (RRLP) and a description
+how it works inside of the GSM network shall be given. RRLP is a protocol from the family of Location Services (LCS)
which were not part of the initial GSM standard. It is a widely used protocol in other cellular
networks like UMTS, it was later introduced to the GSM system as well \citep{3GPPTS03.71}. It was
developed by the request of government and rescue organizations to fulfill the wireless enhanced 911
@@ -1369,12 +1369,12 @@ within 100 m in 67\% of cases \citep{E911Accuracy}.
The standard supports three positioning mechanisms: E-OTD, UL-TDOA and AGPS \citep{3GPPTS03.71}.
The LCS process can be divided into two seperate stages, signal measurements and
position estimation from the derived data in the previous stage. In this chapter
-the description will be given on how to make an RRLP request, how to send assistance
-data and then more information will be given on its response.
+the description shall be given on how to make an RRLP request, how to send assistance
+data and then more information shall be given on its response.
\newpage
\section{RRLP Request}
-In this section the RRLP protocol and its request will be reviewed in more detail.
+In this section the RRLP protocol and its request shall be reviewed in more detail.
RRLP represents the connection/protocol between the Serving Mobile Location Center (SMLC)
and the standalone handset, in this case the MS \citep[Chapter 5]{harper2010server-side}.
The SMLC node contains the functionaly to support
@@ -1382,7 +1382,7 @@ location services for the GSM network \citep{3GPPTS03.71}. SMLCs primary functio
the overall coordination and scheduling of resources required to perform the localization of the MS
and it is located on the Base Station Controller (BSC) \citep{3GPPTS03.71}.
SMLC controls the LMU's as well but since in this work no LMU were available this part
-will be skipped as well as the description of E-OTD and UL-TDOA localization.
+shall be skipped as well as the description of E-OTD and UL-TDOA localization.
Before an attempt is made, of requesting the SMLC to initialize an RRLP request, an SDDCH connection
channel has to be initialized to the MS, this connection can not be seen by the MS user\footnote{However,
@@ -1401,7 +1401,7 @@ connected to the GSM network.}.
Data sent inside of a protocol are called Protocol Data Unit (PDU). On different
layer levels PDU's may take a different shape and size because of the encapsulation or splitting \citep{kozierok2005the} \citep{stevens1994tcp/ip}.
In RRLP, the PDU's sent from the SMLC ought to be not greater than 244 bytes\footnote{Bytes of 8 bits!},
-although the standard defines that larger packets will be split in lower layers, in this work the
+although the standard defines that larger packets shall be split in lower layers, in this work the
rule of 244 bytes has been obeyed and each PDU packet is not greater
than 211 bytes \citep{04.31V8.18.0}. In the RRLP standard terms, the messages are entitled
as \textit{components} and fields in the messages (components) are labelled as \textit{information elements} (IE) \citep{04.31V8.18.0}.
@@ -1409,13 +1409,13 @@ The SMLC may send only the request for the position of the MS or it may assist t
required to estimate the position (in case of an AGPS request, these data may be ephemeris, almanac,
accurate timing data and similar data that help to estimate the position in a shorter period of time).
The RRLP protocol is shown in figure \ref{img:RRLPReqProt}. Dashed lines represent optionally transmitted data
-like assistance data according to which an acknowledgement or error will be produced. Once the MS obtains the RRLP request,
-after a period of processing time it will respond to the SMLC with the position of the MS or with an error IE indicating what
+like assistance data according to which an acknowledgement or error shall be produced. Once the MS obtains the RRLP request,
+after a period of processing time it shall respond to the SMLC with the position of the MS or with an error IE indicating what
assistance data are missing or why it can not return the position \citep{04.31V8.18.0} \citep{49.031V8.1.0}. In the response component IE it is exactly indicated
what type of data ought to be sent to the MS so it can complete the RRLP request and give back its
position. To save bandwidth space in the communication between the SMLC and MS, it can be proceeded in such a manner that
first the RRLP request is sent out for the position estimation and then if the MS requires some of the assistance data,
-it will send a request for those data back to the SMLC and then the SMLC can send the required data and expect an
+it shall send a request for those data back to the SMLC and then the SMLC can send the required data and expect an
successful response from the MS. However, in this work the author had a different approach in that sense, that first
all the RRLP assistance data were sent and then the RRLP position request. This way, sending all assistance data,
was choosen over the other idea of waiting for the MS response because in OpenBSC it was not possible to access
@@ -1430,12 +1430,12 @@ for denoting the abstract syntax of data used inside of protocols or data
structures \citep[Chapter 8]{sharp2008principles} \citep{ITU-TX.680}. In other words, using ASN.1 it is possible
to describe data in an indepedent representation of programming languages in which a protocol is implemented.
In this section, only some of the mostly important and used parts of the RRLP protocol
-inside of the thesis will be presented, more details can be found in the
+inside of the thesis shall be presented, more details can be found in the
technical specifications \citep{49.031V8.1.0} \citep{ETSITS144031}. Structure
of the RRLP message encoding for transmission can be seen in listing \ref{lst:RRLP}.
Further details on some of the unknown terms are given in listings
-\ref{lst:RRLPReq} and \ref{lst:RRLPReqData}. An example how to build an RRLP request packet will be given,
-then it will be encoded using Packed Encoding Rules (PER). PER is one of the telecommunication
+\ref{lst:RRLPReq} and \ref{lst:RRLPReqData}. An example how to build an RRLP request packet shall be given,
+then it shall be encoded using Packed Encoding Rules (PER). PER is one of the telecommunication
standards used for encoding and decoding messages inside of protocols specified in the ASN.1
notation \citep{ITU-TX.691}.
\newpage
@@ -1509,7 +1509,7 @@ there are some wasted padding bits which are set to zero if not used according t
packets.
Before proceeding with an example, summary for the used ASN.1 type
-elements will be provided otherwise it is not possible to proceed with an example
+elements shall be provided otherwise it is not possible to proceed with an example
RRLP request. A type of \textbf{SEQUENCE} is used to
reference a ``fixed, ordered list of types (some of which may be declared to be
optional); each value of the sequence type is an ordered list of values,
@@ -1527,7 +1527,7 @@ first element is of value zero. Variables defined by \textbf{INTEGER} are of the
type with distinguished values which are the positive and negative whole numbers,
including zero (as a single value)'' \citep{ITU-TX.691}.
-At this point the meaning of RRLP data elements colored in red, blue and orange from listing \ref{lst:RRLP} will be given.
+At this point the meaning of RRLP data elements marked in red, blue and orange from listing \ref{lst:RRLP} shall be given.
To construct an RRLP PDU sequence (packet) these fields need to be known: \textit{referenceNumber}
and \textit{RRLP-Component}. \textbf{referenceNumber}
specifies the reference number of the request and is used for the purpose of identifying
@@ -1535,10 +1535,10 @@ the response from the MS. It can take any value between 0 and 7, in
PER enocoding this requires at least a three bit representation since with three bits,
eight different values can be represented ($2^3=8$). \textbf{component} is of the type RRLP-Component,
which is a CHOICE list. RRLP-Component is used for defining what type of information the
-packet will include (assistance data, request, response, error, etc.). For this particular example
-one chooses \textbf{msrPositionReq} that is of type MsrPosition-Req (colored in orange in listing \ref{lst:RRLP}),
-with this information the MS will know that its position is requested. MsrPosition-Req is a SEQUENCE,
-consisting out of one mandatory and few optional IE elements. One choice will be only considered,
+packet shall include (assistance data, request, response, error, etc.). For this particular example
+one chooses \textbf{msrPositionReq} that is of type MsrPosition-Req (marked in orange in listing \ref{lst:RRLP}),
+with this information the MS shall know that its position is requested. MsrPosition-Req is a SEQUENCE,
+consisting out of one mandatory and few optional IE elements. One choice shall be only considered,
\textbf{PositionInstruct}, the rest is used later for the assistance data and what
type of information is included inside of the PDU message. \textbf{PositionInstruct} consists
of five elements but four are mandatory: \textit{methodType}, \textit{positionMethod},
@@ -1548,7 +1548,7 @@ position measurements it could perform, how long (time duration) it is allowed t
the position and how many positions it should perform and return in its response.
\newpage
\textbf{methodType} defines where the position estimation calculation ought to be executed,
-will it take place solely on the MS (\textit{msBased}), solely on the server\footnote{With server
+shall it take place solely on the MS (\textit{msBased}), solely on the server\footnote{With server
the BTS location is ment!} (\textit{msAssisted}),
or one is prefered over the other depending if the MS can execute the prefered one
(\textit{msBasedPref} or \textit{msAssistedPref}). The uncertainty of the accuracy
@@ -1618,7 +1618,7 @@ the position measurement time and how many measurements the MS ought to report b
Since in this thesis the author exploits the AGPS method, GPS is choosen for \textbf{PositionMethod}.
\textbf{MeasureResponseTime} is a three bit integer value that corresponds to the time the MS is allowed
to perform the position estimation and to send a respose back to SMLC. Otherwise, if it takes longer the MS
-than the specified time period, it will disconnect the SDDCH channel without responding back.
+than the specified time period, it shall disconnect the SDDCH channel without responding back.
It can be calculated using the equation
given in \eqref{eq:responseTime}, where $N$ is the number of seconds the MS is allowed to perform the
position estimation.
@@ -1631,12 +1631,12 @@ into a binary string. A simple
RRLP request in PER encoded form is shown in figure \ref{img:RRLPReqExplained} and the previous conversion
process might become more clear, different variables have been colored with distinguishable colors to its neighbor
variables so that it is easy to recognize different variables. The five red zeros define what type of data
-will be included in the current RRLP packet. This becomes more understandable by looking at the listing \ref{lst:RRLPReqPER}.
+shall be included in the current RRLP packet. This becomes more understandable by looking at the listing \ref{lst:RRLPReqPER}.
After the concationation it can be converted to the
desired notation system (binary, hexadecimal, etc.). In this particular example the RRLP request to be sent
using the RRLP protocol in hexadecimal notation is: \textbf{400178F8}. This message is transmitted to the MS
via the opened SDDCH channel. However, before sending this request the assistance data can be sent. In the
-folowing section \ref{sec:rrlpassistance} more details of how assistance data are sent will be presented.
+folowing section \ref{sec:rrlpassistance} more details of how assistance data are sent shall be presented.
\begin{figure}[ht!]
\centering
\includegraphics[scale=0.80]{img/RRLPReqExplained.pdf}
@@ -1719,7 +1719,7 @@ on its on \citep[Chapter 4]{harper2010server-side}. This would speed up the proc
position and would help weak signals to be detected which in return would minimize the reception errors.
More information on the assistance data transmitted within the RRLP protocol
-in this work will be presented here. As listed above,
+in this work shall be presented here. As listed above,
almanac, ephemeris, UTC model, ionospheric model and reference location are transmitted to the MS. Reference
location is the location of the BTS and provides the MS with an approximate location which can be used
for the position determination in equations given in section \ref{sec:distanceAndPosition}.
@@ -1735,20 +1735,20 @@ all satellites \citep[Chapter 4]{harper2010server-side}. Navigation data in RRLP
The transmitted assistance data can be seen in the following tables \ref{tbl:utcModel}, \ref{tbl:navMessage},
\ref{tbl:almanacMessage} and \ref{tbl:ionoModel}, on the following pages \pageref{tbl:utcModel},
\pageref{tbl:navMessage} and \pageref{tbl:almanacMessage}. How other
-data are encoded will be given in the implementation chapter, chapter \ref{Implementation}.
+data are encoded shall be given in the implementation chapter, chapter \ref{Implementation}.
The packets are constructed in the same manner as RRLP requests with a slight difference of selecting
different RRLP components and including assistance data. In this particular example,
-only a packet with the reference location will be presented, a ``complete'' 211 bytes PDU packet constructed by author's
+only a packet with the reference location shall be presented, a ``complete'' 211 bytes PDU packet constructed by author's
software would require at least four pages to be shown. Instead of RRLP request (\textit{msrPositionReq})
in \textbf{RRLP-Component} one has to choose assistance data (\textit{assistanceData}) (for the purpose
of better understanding in this listening different colors have been used,
this particular difference was bolded in listing \ref{lst:RRLPAssisPER}). Afterwords one
needs to specify what type of assistance the packet includes, in this case it is GPS assistance
-data (\textit{gps-AssistData}, colored red in listing \ref{lst:RRLPAssisPER}). GPS assistance data were described in the
-two previous paragraphs and therefore will be omitted here. They will be only listed in the order as
+data (\textit{gps-AssistData}, marked in red color in listing \ref{lst:RRLPAssisPER}). GPS assistance data were described in the
+two previous paragraphs and therefore shall be omitted here. They shall be only listed in the order as
specified in the RRLP standard for GPS assistance data, listing \ref{lst:GPSAssisData}: reference time, reference location, DGPS corrections, navigation model,
-ionospheric model, UTC model, almanac, acquisition assistance and real time integrity (all colored blue in
+ionospheric model, UTC model, almanac, acquisition assistance and real time integrity (all marked with blue color in
listing \ref{lst:RRLPAssisPER}). The assistance data one
wants to include in the RRLP packet have to be selected previously.
Selecting is straightforward and one only is required to set
@@ -1785,7 +1785,7 @@ ControlHeader ::= SEQUENCE {
The reference location consists of longitude, latitude, altitude, uncertainty semi-major,
uncertainty semi-minor, orientation of major axis, uncertainty of altitude and confidence
-level. \textbf{S} is sign of the latitude, it is set to one if it is North and zero if
+level. \textbf{S} is sign of the latitude, it is set to zero if it is North and one if
it is South. \textbf{D} is the altitude direction, it is set to zero if the altitude that
follows is height and to one if it is depth. Uncertainty semi-major and uncertainty semi-minor
are uncertainties for longitude and latitude. Orientation of major axis is the orientation angle
@@ -1832,12 +1832,12 @@ What type of reference location is include is defined by the first four bits of
in this case it is $1001$, as it can be seen in figure \ref{img:refLocStandard}. This is an additional
mechanism for error control, if the numbers do not match when the transmitted binary data have been decoded
then the MS can return an error and ask for retransmission of the data. Information related to the reference
-location in the example listing \ref{lst:RRLPAssisPER} are colored in orange. Once the assistance data
-have been transmitted to the MS, it will respond back with an acknowledgement or error depending if the
-data were correctly received and parsed by the MS. The acknowledgement will have the same reference number
+location in the example listing \ref{lst:RRLPAssisPER} are marked with orange color. Once the assistance data
+have been transmitted to the MS, it shall respond back with an acknowledgement or error depending if the
+data were correctly received and parsed by the MS. The acknowledgement shall have the same reference number
as the assistance packet. This can be seen as well in figure \ref{img:RRLPReqProt}.
In the next section more
-details will be given on the RRLP response from the MS.
+details shall be given on the RRLP response from the MS.
\begin{equation}
\label{eq:latLong}
\begin{array}{l}
@@ -2066,19 +2066,19 @@ D9 1101....
\end{lstlisting}
\clearpage
\section{RRLP Response}
-In this section the RRLP response from the MS will be analysed. The RRLP response is
+In this section the RRLP response from the MS shall be analysed. The RRLP response is
constructed in the same manner as the RRLP request and assistance data by following
ASN.1 rules precisely specified in the RRLP standard. RRLP response is produced by the MS itself.
It may include the estimated position, data for estimating the position on the BTS (if MS assisted was
choosen as the prefered method) or errors indicating that some of the
previously mentioned assistance data are missing. Missing data and errors are
-specified inside of the RRLP response. The response data will be PER encoded and require
+specified inside of the RRLP response. The response data shall be PER encoded and require
to be decoded into the ASN.1 notation. In listing \ref{lst:RRLPRespError} an example of an
RRLP response with an error can be seen. The location error bit is set if the location
-of the MS is not present within the message (colored in red). The MS may sometimes supply more
+of the MS is not present within the message (marked in red). The MS may sometimes supply more
information on the error if the MS knows this information (newer models support this).
-In case it does support more information, it will set an optional IE \textit{additionalAssistanceData} bit
-(colored in cyan).
+In case it does support more information, it shall set an optional IE \textit{additionalAssistanceData} bit
+(marked in cyan).
\begin{lstlisting}[label=lst:RRLPRespError,
caption={\textbf{Decoding an error RRLP response from Samsung Galaxy S3}},
backgroundcolor=\color{light-gray},
@@ -2125,13 +2125,13 @@ D0 11010000
.......0 Spare Bits = 0b
\end{lstlisting}
This is followed with a more detailed explanation of the error that not sufficient
-assistance data were present, \textit{LocErrorReason} (colored in blue). There
+assistance data were present, \textit{LocErrorReason} (marked with blue color). There
are other possible location error reasons as well and they are listed in listing
\ref{lst:RRLPPosError}. Depending on the MS model, it can even further specify
-what kind of GPS assistance data are missing. This will be well specified by setting
+what kind of GPS assistance data are missing. This shall be well specified by setting
the IE \textit{gpsAssistanceData} bit, this is shown in listing \ref{lst:RRLPRespError}
-(colored in magenta). If this bit is set, the length of the IE for requested missing assistance
-data will be exactly specified as well as what assistance data are missing (colored in orange).
+(marked with magenta color). If this bit is set, the length of the IE for requested missing assistance
+data shall be exactly specified as well as what assistance data are missing (marked in orange color).
\begin{lstlisting}[label=lst:RRLPPosError,
caption={\textbf{Possible location error reasons}},
backgroundcolor=\color{light-gray},
@@ -2160,13 +2160,27 @@ LocErrorReason ::= ENUMERATED {
\label{img:RequestedGPSAss}
\end{figure}
The first two bytes of the IE \textit{GPSAssistanceData} contain the information for requested
-assistance AGPS data (colored in orange). They can be seen
+assistance AGPS data (marked in orange color). They can be seen
in figure \ref{img:RequestedGPSAss} \citep{49.031V8.1.0}. If one of these bits from A to K is set,
the MS requires more assistance data. The meaning of the bits in figure \ref{img:RequestedGPSAss}
is given in table \ref{tbl:RRLPReqAss}. In this particular example, the first two bytes are: \textbf{E800},
indicating acquisition assistance, reference time, reference location and the navigation model are requsted
by the MS as assistance data. The next RRLP response example, shown in listing \ref{lst:RRLPRespSucc}, is
-a response with successfully estimated position!
+a response with a successfully estimated position! A successful or erroneous position response
+is of RRLP measurement responses type, this can be seein in listing \ref{lst:RRLPRespSucc}
+(bolded, in listing \ref{lst:RRLPRespError} it is bolded as well). It can not be
+distinguished by analysing the first byte of the response stream! In the second byte, two mutually exclusive IE
+contain the information if the response contains the location information or not, \textit{locationInfo} bit must
+be set and \textit{locationError} must be unset (both marked in red color in listing \ref{lst:RRLPRespSucc}).
+If the IE \textit{locationInfo} bit is one and \textit{locationError} bit zero, then the position of the MS is
+included in the response. Aside from the position information, the time when the position measurement
+was performed is included as well however, only the least significant bits in the range of miliseconds. The
+most significant bits shall be derived by the SMLC using the GSM frame number, included in the IE \textit{refFrame}.
+\textit{refFrame} contains the GSM frame number as observed by the MS without the TA factor taken into account \citep{49.031V8.1.0}!
+The time of miliseconds can be found in the IE \textit{gpsTOW}. The included time is
+not in UTC format and would require additional conversions.
+The elements of \textit{locationInfo} can be seen in listing \ref{lst:RRLPLocInfo}. The IE \textit{fixType} contains
+the information if the performed measurement was 2D or 3D.
\begin {table}[ht]
\caption{Requested AGPS assistance data bit meaning}
\label{tbl:RRLPReqAss}\centering
@@ -2190,8 +2204,34 @@ $K$&Ephemeris extension check requested
\\\bottomrule
\end {tabular}
\end {table}
+\begin{lstlisting}[label=lst:RRLPLocInfo,
+caption={\textbf{Structure of data types of location info data in ASN.1}},
+backgroundcolor=\color{light-gray},
+basicstyle=\scriptsize\ttfamily,
+escapechar=@]
+-- Location information IE
+LocationInfo ::= SEQUENCE {
+ refFrame INTEGER (0..65535), -- Reference Frame number
+ -- If refFrame is within (42432..65535), it shall be ignored by the receiver
+ -- in that case the MS should provide GPS TOW if available
+ gpsTOW INTEGER (0..14399999) OPTIONAL, -- GPS TOW
+ fixType FixType,
+ -- Note that applicable range for refFrame is 0 - 42431
+ -- Possible shapes carried in posEstimate are
+ -- ellipsoid point, ellipsoid point with uncertainty circle,
+ -- ellipsoid point with uncertainty ellipse,
+ -- ellipsoid point with altitude and uncertainty ellipsoid
+ posEstimate Ext-GeographicalInformation
+}
-\clearpage
+FixType ::= INTEGER {
+ twoDFix (0),
+ threeDFix (1)
+} (0..1)
+\end{lstlisting}
+The position information is extracted with the inverse process as it was specified for the reference location.
+Equations to return from the bit format to decimal degrees are given in equation \eqref{eq:latLongBack}. %\clearpage
+In the next chapter, more details shall be given on the implementation of the complete system.
\begin{lstlisting}[label=lst:RRLPRespSucc,
caption={\textbf{Decoding a successful RRLP response from iPhone 3GS}},
backgroundcolor=\color{light-gray},
@@ -2214,7 +2254,7 @@ emphstyle={[2]\color{blue}}]
..0..... otd-MeasureInfo = 0 :Absent
...1.... @\textcolor{red}{locationInfo = 1 :Present}@
....0... gps-MeasureInfo = 0 :Absent
- .....0.. locationError = 0 :Absent
+ .....0.. @\textcolor{red}{locationError = 0 :Absent}@
......0. extensionContainer = 0 :Absent
LocationInfo:
.......1 gpsTOW = 1 :Present
@@ -2244,6 +2284,26 @@ B6 1....... FixType = 1 :threeDFix
10 000100..
......00 Spare Bits = 00b
\end{lstlisting}
+\begin{equation}
+\label{eq:latLongBack}
+\begin{array}{l}
+\begin{split}
+ \varphi = \frac{90}{2^{23}}\cdot Lat
+ \end{split}
+\quad\Longleftarrow\quad
+ \begin{split}
+ \mbox{Latitude in decimal degrees}
+ \end{split}\\
+ \\
+\begin{split}
+ \lambda = \frac{360}{2^{24}}\cdot Long
+ \end{split}
+\quad\Longleftarrow\quad
+ \begin{split}
+ \mbox{Longitude in decimal degrees}
+ \end{split}
+\end{array}
+\end{equation}
@@ -2258,6 +2318,7 @@ B6 1....... FixType = 1 :threeDFix
\chapter{Implementation}
\label{Implementation}
+This chapter seeks to give a review of the software implementation in this thesis.
-from rinex conversion\\
explain rinex form \\
@@ -2274,15 +2335,15 @@ the fact that the channel was free, measurements were carried out with a
spectrum analyser built on the USRP hardware.
\chapter{Hardware}
-In the following chapter the author will introduce the reader to the hardware
-components used in the thesis. The hardware components will be presented
+In the following chapter the author shall introduce the reader to the hardware
+components used in the thesis. The hardware components shall be presented
according to their importance of building an operational and
functional GSM network with GPS localization capabilities. Firstly the nanoBTS
-will be introduced since it is the main hardware component used for building a
+shall be introduced since it is the main hardware component used for building a
basic GSM network infrastructure. Then a short insight into the used
-GPS receiver will be given. Additionally the mobile stations used for
-testing of the system will be reviewed. Finally, a hardware connection diagram
-will be given.
+GPS receiver shall be given. Additionally the mobile stations used for
+testing of the system shall be reviewed. Finally, a hardware connection diagram
+shall be given.
\section{GSM BTS - nanoBTS}
In recent years, there has been an increasing interest in deployment of
@@ -2319,7 +2380,7 @@ in this work.\todo{Check for what NWL is}
At the bottom of the nanoBTS there are 5 ports, as seen in Figure \ref{img:nanoBTSPorts}.
The ports from left to right are: voltage supply, ethernet cable with power supply, USB
-port, TIB-IN and TIB-OUT. In the next paragraph a brief overview of each port will be given.
+port, TIB-IN and TIB-OUT. In the next paragraph a brief overview of each port shall be given.
\begin{figure}[ht!]
\centering
@@ -2335,7 +2396,7 @@ 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
-will be given in section \ref{sec:hardwareConfig}. In the middle of the five port region,
+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
for Timing Interface Bus}. These two ports are used if the GSM network operator requires more
@@ -2343,13 +2404,13 @@ than 11 channels to increase the overall capacity of the network.
``Up to 4 nanoBTS can be combined into a multiple TRX cell, increasing the number of
supported users per TRX by up to 200\%. The TIB-OUT from the Master TRX must be connected to
the TIB-IN of the slave TRX. This in turn has its TIB-OUT connected to the next TRX in the chain''
-\citep{multipleTRX}. The multiple TRX cell configuration will not be further discussed in this work
+\citep{multipleTRX}. The multiple TRX cell configuration shall not be further discussed in this work
since the purpose of the work was not to boost the capacity of a GSM network but implementation
and testing of the RRLP protocol.
To determine the working state of the nanoBTS, an indicator status LED is located on the
left side of the five ports region. After the nanoBTS is connected to the power suplly
-with the ethernet cable, it will change its color and blink speed according to the state
+with the ethernet cable, it shall change its color and blink speed according to the state
it is in. The states can be seen in the Table given in \ref{tbl:LEDStatus} \citep{installnanoBTS}.
One of the key limitations of gathering more technical data and the critical aspect of this
@@ -2389,7 +2450,7 @@ are sufficient for reproducing and conducting the RRLP tests described in this t
\newpage
\section{GPS Receiver - NL-402U}
\label{sec:gpsDevice}
-In the next paragraphs the used GPS device will be described.
+In the next paragraphs the used GPS device shall be described.
In contrast to the earlier described hardware, nanoBTS, which the University of Freiburg
already owned, the budget for the GPS receiver was limited and the Navilock NL-402U
was bought considering only the single criterion, the price. The Navilock NL-402U
@@ -2416,7 +2477,7 @@ which are serial communication interfaces.
\section{Cable configuration}
\label{sec:hardwareConfig}
-In the next section, the author will focus on properly connecting the hardware.
+In the next section, the author shall focus on properly connecting the hardware.
At least 4 ethernet cables with RJ45 connectors, on both sides, were required
and one switch or hub connected to the internet. One should
take notice of the cabling between the nanoBTS and the ethernet switch or hub,
diff --git a/vorlagen/thesis/src/maindoc.lof b/vorlagen/thesis/src/maindoc.lof
index f566cdb..d18a8ce 100644
--- a/vorlagen/thesis/src/maindoc.lof
+++ b/vorlagen/thesis/src/maindoc.lof
@@ -13,7 +13,7 @@
\contentsline {figure}{\numberline {2.5}{\ignorespaces Modulation of the GPS signal L1\relax }}{18}{figure.caption.17}
\contentsline {figure}{\numberline {2.6}{\ignorespaces Two equivalent carrier waves with the same frequency but different phase shift\relax }}{21}{figure.caption.18}
\contentsline {figure}{\numberline {2.7}{\ignorespaces Demodulation of the L1 GPS signal\relax }}{21}{figure.caption.19}
-\contentsline {figure}{\numberline {2.8}{\ignorespaces Effects of the low frequency term on the demodulated output C/A wave on the GPS receiver (the explanations and figures are from top to bottom). If the synthesized frequency is correct, $f_{1}=f_{2}$, the low frequency term becomes a DC term and does not modify the output $d_{C/A}$ wave (first figure). If the frequency matches but the 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 $d_{C/A}$ will vary as well (third figure).\relax }}{23}{figure.caption.20}
+\contentsline {figure}{\numberline {2.8}{\ignorespaces Effects of the low frequency term on the demodulated output C/A wave on the GPS receiver (the explanations and figures are from top to bottom). If the synthesized frequency is correct, $f_{1}=f_{2}$, the low frequency term becomes a DC term and does not modify the output $d_{C/A}$ wave (first figure). If the frequency matches but the 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).\relax }}{23}{figure.caption.20}
\contentsline {figure}{\numberline {2.9}{\ignorespaces 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.\relax }}{24}{figure.caption.21}
\contentsline {figure}{\numberline {2.10}{\ignorespaces Cross-correlation on three different signals\relax }}{25}{figure.caption.22}
\contentsline {figure}{\numberline {2.11}{\ignorespaces Segment of the frequency/code delay search space for a single GPS satellite\relax }}{27}{figure.caption.23}