ii
Dedicated to our beloved country YEMEN

iii
ACKNOWLEDGMENTS
First and foremost, we thank God who assisted us to reach this success.
Then, we express our profuse thanks and valuable esteem for our supervisor Dr. Redhwan
Qasem Shaddad, to give us the confidence in ourselves and for his guidance and valuable time
spent on those numerous discussions that we had at the office. It is in those fruitful
discussions that we learned many more things apart from project it and we are sure that those
will be helpful in future. Thanks for everything.
Finally, we express our esteem for generous parents who have supported us along period
of study and did all of the above and more. Without them, none of this work would have been
carried out.

iv
ABSTRACT
In the world of modern wireless communications, planning and optimization of a cellular
network is the most important phase in its life cycle. The aim of this operation is to minimize
the cost of the radio link and the network infrastructure, taking into account the distribution of
subscribers, the location of the area to cover and the quality of service constraints. Planning of
Long Term Evolution (LTE) network determines the estimation of traffic handled, and defines
the traffic carried in a cell. The planning is influenced by the number of subscribers in a cell,
the type of application and the interference due to wave propagation in the air.
For a planning network, a careful optimization of the network is necessary. The analytical
data is collected and practical design methodologies are used to obtain an optimum network to
increase the network performance, while reducing the time and expenses required for
network implementation. Network planning and optimization are the most significant parts of
the network design, which should be considered from three different perspectives: service,
coverage and capacity.
In this project, the coverage and capacity planning, and optimization are proposed for the
urban areas at Taiz city.
The major problem in the obtained result is that these results don't represent the real values
but in order to make this Radio Access Network (RAN) planning stage more accurate, the
inclusion of the terrain model has to be considered in simple manners, so that improvement in
the result is obtained while the simplicity of the process is still maintained.
This project involves hands-on simulation exercise on planning of Radio Frequency (RF)
network with the help of ATOLL planning software tool. The main aim of radio network
planning is to provide a cost effective solution for the radio network in terms of coverage,
capacity and quality. Using Spectrum flexibility very preciously to cater many user in a vast
area with good quality, coverage, and without interference.

v
ARABIC ABSTRACT
‫المستخلص‬
‫تعتبر‬‫شبكة‬LTE‫من‬‫ال‬‫شبكات‬‫ذات‬ ‫الالسلكية‬‫ال‬ ‫النطاق‬،‫واسع‬‫الو‬ ‫نقل‬ ‫على‬ ‫قادرة‬ ‫وهي‬‫المتعددة‬ ‫سائط‬‫شبكة‬ ‫برج‬ ‫بين‬
‫ال‬‫جيد‬ ‫باعتمادية‬ ‫والمستخدمين‬ ‫محمول‬.‫ة‬‫لك‬ ‫يؤهلها‬ ‫المتعددة‬ ‫الوسائط‬ ‫نقل‬ ‫على‬ ‫الشبكة‬ ‫هذه‬ ‫مقدرة‬ ‫إن‬‫من‬ ‫العديد‬ ‫في‬ ‫تستخدم‬ ‫ى‬
‫التطبيقات‬،‫تعتبر‬‫شبكة‬LTE‫بداية‬.‫المحمول‬ ‫لشبكات‬ ‫الرابع‬ ‫الجيل‬
‫عالم‬ ‫في‬‫وتحسين‬ ‫تخطيط‬ ،‫الحديثة‬ ‫الالسلكية‬ ‫االتصاالت‬‫ا‬‫ه‬ ‫الخلوية‬ ‫لشبكة‬‫ما‬‫أهم‬‫ال‬‫مر‬‫ا‬‫حل‬‫ه‬ ‫من‬ ‫والهدف‬ .‫حياتها‬ ‫دورة‬ ‫في‬‫ذه‬
‫تكلفة‬ ‫تقليل‬ ‫هو‬ ‫العملية‬‫وصلة‬،‫المشتركين‬ ‫توزيع‬ ‫االعتبار‬ ‫بعين‬ ‫األخذ‬ ‫مع‬ ،‫للشبكة‬ ‫التحتية‬ ‫والبنية‬ ‫الراديو‬‫وموقع‬‫ال‬‫منطقة‬
‫ا‬‫لمغطاة‬‫الخدمة‬ ‫جودة‬ ‫وقيود‬.‫التخطيط‬ ‫يتأثر‬ ‫و‬‫ب‬‫خلية‬ ‫في‬ ‫المشتركين‬ ‫عدد‬‫معينة‬‫النتشار‬ ‫المناسب‬ ‫والتدخل‬ ‫التطبيق‬ ‫ونوع‬ ،
.‫الهواء‬ ‫في‬ ‫الموجات‬
‫شبكة‬ ‫لمخطط‬ ً‫ا‬‫ضروري‬ ً‫ا‬‫أمر‬ ‫الدقيق‬ ‫التحسين‬LTE،‫جمع‬ ‫يتم‬‫وتستخدم‬ ‫التحليلية‬ ‫البيانات‬‫على‬ ‫للحصول‬ ‫عملية‬ ‫منهجيات‬
‫أداء‬ ‫لزيادة‬ ‫محسنة‬ ‫شبكة‬‫وكفاءة‬‫لتنفي‬ ‫الالزمة‬ ‫والنفقات‬ ‫الوقت‬ ‫من‬ ‫الحد‬ ‫مع‬ ،‫الشبكة‬‫ه‬ ‫الشبكة‬ ‫وتحسين‬ ‫تخطيط‬ .‫الشبكة‬ ‫ذ‬‫ما‬‫أهم‬
‫مرحلتين‬.‫والسعة‬ ‫والتغطية‬ ‫الخدمة‬ :‫مختلفة‬ ‫زوايا‬ ‫ثالث‬ ‫من‬ ‫فيها‬ ‫النظر‬ ‫ينبغي‬ ‫والتي‬ ،‫الشبكات‬ ‫تصميم‬ ‫من‬
‫من‬ ‫الغرض‬‫هذا‬‫و‬ ‫تخطيط‬ ‫هو‬ ‫المشروع‬‫تحسين‬‫ا‬‫لمن‬‫طقة‬‫الحضرية‬‫ل‬‫ح‬ ‫من‬ ‫تعز‬ ‫مدينة‬.‫والسعة‬ ‫التغطية‬ ‫يث‬
‫النت‬ ‫في‬ ‫الرئيسية‬ ‫المشكلة‬‫ائج‬‫تمثل‬ ‫ال‬ ‫النتائج‬ ‫هذه‬ ‫أن‬ ‫هي‬ ‫عليها‬ ‫نحصل‬ ‫التي‬‫و‬ ‫الحقيقية‬ ‫القيم‬‫ذلك‬‫بسبب‬‫الجغرافية‬ ‫الطبيعة‬
‫للمنطقة‬‫التي‬‫تتغير‬‫باستمرار‬‫والشوارع‬ ‫المباني‬ :‫المثال‬ ‫سبيل‬ ‫على‬‫والسكان‬.
‫ا‬ ‫هذا‬ ‫ويشمل‬‫العملي‬ ‫التدريب‬ ‫لمشروع‬‫شبك‬ ‫تخطيط‬ ‫على‬ ‫محاكاة‬( ‫الراديو‬ ‫ترددات‬ ‫ة‬RF‫البرمجية‬ ‫التخطيط‬ ‫أداة‬ ‫بمساعدة‬ )
ATOLL.
‫ت‬ ‫من‬ ‫الرئيسي‬ ‫الهدف‬‫حسين‬‫الراديو‬ ‫شبكة‬‫هو‬‫توفير‬‫حل‬‫كفؤة‬ ‫ول‬‫ل‬‫شبكة‬.‫والجودة‬ ‫والسعة‬ ‫التغطية‬ ‫حيث‬ ‫من‬ ‫الراديو‬‫وذلك‬
‫ب‬‫الطيف‬ ‫مرونة‬ ‫استخدام‬‫الترددي‬‫ج‬ ‫نوعية‬ ‫مع‬ ‫واسعة‬ ‫منطقة‬ ‫في‬ ‫المستخدمين‬ ‫من‬ ‫العديد‬ ‫احتياجات‬ ‫لتلبية‬‫وتغطية‬ ،‫يدة‬‫شاملة‬،
.‫تدخل‬ ‫أي‬ ‫ودون‬

vi
TABLE OF CONTENTS
ACKNOWLEDGMENTS .............................................................................................................. III
ABSTRACT .................................................................................................................................IV
ARABIC ABSTRACT ....................................................................................................................V
TABLE OF CONTENTS ...............................................................................................................VI
LIST OF FIGURES ...................................................................................................................... IX
LIST OF TABLES ........................................................................................................................ XI
LIST OF ABBREVIATIONS ........................................................................................................ XII
CHAPTER 1 ................................................................................................................................. 1
INTRODUCTION ......................................................................................................................... 1
1.1 INTRODUCTION ....................................................................................................................... 1
1.1.1 Background of Study ......................................................................................................... 1
1.1.2 Main Idea........................................................................................................................ 2
1.1.3 Methodology.................................................................................................................... 2
1.2 STATEMENT OF PROBLEM.......................................................................................................... 3
1.3 OBJECTIVES ........................................................................................................................... 3
1.4 SCOPE OF STUDY ..................................................................................................................... 4
1.5 REPORT OUTLINE .................................................................................................................... 4
CHAPTER 2 ................................................................................................................................. 6
LITERATURE REVIEW ............................................................................................................... 6
2.1 INTRODUCTION ....................................................................................................................... 6
2.2 ARCHITECTURE OF LTE ............................................................................................................ 6
2.2.1 User Equipment (UE) ........................................................................................................ 7
2.2.2 The Access Network .......................................................................................................... 7
2.2.3 The Core Network............................................................................................................. 8
2.2.4 The Interfaces .................................................................................................................. 9
2.3 LTE RADIO INTERFACE ARCHITECTURE ....................................................................................... 9
2.3.1 Non-Access Stratum Layer (NAS)........................................................................................10
2.3.2 Radio Resource Control Layer (RRC) ..................................................................................11
2.3.3 Packet Data Convergence Protocol Layer (PDCP( ...............................................................11
2.3.4 Radio Link Control Layer (RLC).........................................................................................11
2.3.5 Medium-Access Control layer (MAC) ..................................................................................12
2.3.6 Physical Layer (PHY).......................................................................................................13
2.4 TECHNOLOGIES FOR LTE .........................................................................................................14
2.4.1 MIMO Transmission ........................................................................................................14
2.4.2 Spectrum Flexibility .........................................................................................................16
2.4.3 Bandwidth Flexibility .......................................................................................................16
2.4.4 Transmission Schemes ......................................................................................................17
2.5 INTER-CELL INTERFERENCE COORDINATION (ICIC) TECHNOLOGY ...................................................19
2.6 NETWORK PLANNING ..............................................................................................................22
2.6.1 LTE Dimensioning Process................................................................................................22

vii
2.6.2 LTE Coverage Process .....................................................................................................22
2.6.3 LTE Capacity Planning...................................................................................................25
2.7 LTE OPTIMIZATION ................................................................................................................27
2.7.1 LTE Key Performance Indicators (KPIs) ..............................................................................27
2.7.2 Network Optimization.......................................................................................................28
2.8 COMPARISON OF OUR STUDY AND ELSE STUDY ............................................................................34
2.9 SUMMARY ............................................................................................................................35
CHAPTER 3 ................................................................................................................................37
METHODOLOGY........................................................................................................................37
3.1 INTRODUCTION ......................................................................................................................37
3.2 NETWORK PLANNING ..............................................................................................................38
3.3 COVERAGE AND CAPACITY PLANNING.......................................................................................41
3.4 ATOLL MODELING ................................................................................................................42
3.4.1 Area of Planning .............................................................................................................42
3.4.2 Designing of LTE Network.................................................................................................42
3.5 SIMULATION AND ANALYSIS .....................................................................................................45
3.5.1 Coverage Prediction by DL Transmitters..............................................................................45
3.5.2 Coverage Prediction by DL Signal level...............................................................................46
3.5.3 Overlapping Zone ............................................................................................................46
3.5.4 Coverage by C/(I+N) Downlink..........................................................................................46
3.5.5 Coverage Prediction by DL+UL throughput .........................................................................49
3.5.6 Traffic Distribution on the Map ..........................................................................................50
3.6 NETWORK OPTIMIZATION.........................................................................................................51
3.7 SUMMARY ............................................................................................................................52
CHAPTER 4 ................................................................................................................................53
RESULTS AND DISCUSSIONS.....................................................................................................53
4.1 INTRODUCTION ......................................................................................................................53
4.2 PEAK RLC CUMULATED DL+UL THROUGHPUT (KBPS) ..................................................................53
4.3 CONNECTION SUCCESS RATE (%)...............................................................................................54
4.4 PEAK RLC CUMULATED DL THROUGHPUT (KBPS) FOR SERVICE ......................................................55
4.5 PRECENTAGE OF USER APT TO BE SERVED ...................................................................................55
4.6 COVERAGE PREDICTION ON OVERLAPPING ZONES .........................................................................57
4.7 COVERAGE PREDICTION BY DL SIGNAL LEVEL .............................................................................58
4.8 COVERAGE PREDICTION BY DL THROUGHPUT ..............................................................................58
4.9 AUTOMATIC CELL PLANNING (ACP) ..........................................................................................59
4.10 PERFORMANCE ANALYSIS OF PLANNED NETWORK.......................................................................62
4.11 SUMMARY...........................................................................................................................63
CHAPTER 5 ................................................................................................................................64
CONCLUSIONS AND FUTURE WORKS.......................................................................................64
5.1 INTRODUCTION ......................................................................................................................64
5.2 CONCLUSIONS........................................................................................................................64
5.3 FUTURE WORKS .....................................................................................................................65
REFERENCES.............................................................................................................................66

ix
LIST OF FIGURES
Figure (2.1) The EPS network elements……………………………………………... 6
Figure (2.2) LTE protocol stack…………………………………………….….......... 10
Figure (2.3) MIMO technology……………………………………………………... 14
Figure (2.4) Flexibility in duplex arrangement: FDD and TDD…………………….. 15
Figure (2.5) OFDMA downlink multiple access…………………………………….. 17
Figure (2.6) Transmission of 4 modulation symbols using OFDMA and SC-
FDMA………………………………………………………………… 19
Figure (2.7) Inter-Cell Interference Coordination (ICIC) technology…………….... 21
Figure (2.8) Frequency reuse schemes……………………………………………… 21
Figure (2.9) Static partition based schemes………………………………………… 22
Figure (2.10) LTE dimensioning process…………………………………………….. 23
Figure (2.11)
Figure (2.12)
Link budget scheme…………………………………………………….
Optimization framework………………………………………………..
24
31
Figure (3.1) Planning an LTE network – workflow…………………………………. 39
Figure (3.2) Map of the study region………………………………………………… 43
Figure (3.3) Digital map of Taiz urban…………………………………………….... 43
Figure (3.4) Ortho map of Taiz urban………………………………………………. 44
Figure (3.5) Clutter class and vectors map of Taiz urban…………………………… 44
Figure (3.6) Urban area of Taiz city with sites and transmitter……………………… 45
Figure (3.7) Simulation an LTE network –flowchart ……………………………….. 47
Figure (3.8) Coverage prediction by transmitter…………………………………….. 48
Figure (3.9) Coverage prediction by dl signal level…………………………………. 48
Figure (3.10) Coverage prediction on overlapping zones…………………………….. 48
Figure (3.11) PDCCH coverage prediction On C/(I+N) downlink…………..………. 49
Figure (3.12) Coverage prediction on DL throughput………………………………… 49
Figure (3.13) The traffic distribution in urban area according to service…………….. 50
Figure (3.14) The traffic distribution in urban area according to terminal types……... 50
Figure (3.15) The traffic distribution in urban area according to mobility type……… 51
Figure (4.1) Peak RLC cumulated DL+UL throughput (kbps)……………………… 54
Figure (4.2) Connection success rate (%)..................................................................... 54

x
Figure (4.3) Max DL+UL throughput for service before optimization……………… 55
Figure (4.4) Peak RLC cumulated DL throughput (kbps) for service after
optimization…………………………………………………………….. 55
Figure (4.5) Statistic of simulation by user………………………………………….. 56
Figure (4.6) Overlapping zone before optimization…………………………………. 57
Figure (4.7) Overlapping zone after optimization…………………………………… 57
Figure (4.8) Coverage by DL signal level before optimization……………………… 58
Figure (4.9) Coverage by DL signal level after optimization………………………. 58
Figure (4.10) Coverage by DL throughput before optimization……………………… 59
Figure (4.11) Coverage by DL throughput after optimization………………………... 59
Figure (4.12) Statistics of optimization result………………………………………… 60
Figure (4.13) Graph of optimization result……………………………………………. 60
Figure (4.14) Point analysis tool – Profile tab………………………………………… 63

xi
LIST OF TABLES
Table (2.1) The LTE UE categories……………………………………………… 7
Table (2.2) Logical channels of the LTE………………………………………… 12
Table (2.3) Transport channels of the LTE………………………………………. 12
Table (2.4) Physical channels of the LTE……………………………...………… 13
Table (2.5) Number of PRBs for the allocated bandwidths……………………… 19
Table (2.6) Example for a link budget of downlink….…………………………... 24
Table (2.7) Site coverage area and inter _site distance…………………………... 24
Table (2.8) LTE 2600 MHz cell average throughput with different bandwidth…. 26
Table (2.9) Maximum number of active users per cell…………………………... 27
Table( 2.10)
Table (3.1)
Comparison of our study and last study……………………………..
Planning parameters for downlink and uplink of the proposed LTE
network…………………………………………………………….....
35
40
Table (4.1) ACP optimization……………………………………………………. 61
Table (4.2) Success and fail coverage ratio………………………………………. 62
Table (4.3) Link budget Obtained from point analysis tool of Cairo Castle_1…... 63

xii
LIST OF ABBREVIATIONS
3GPP
AFP
Third Generation Partnership Project
Automatic Frequency Planning
ACP Automatic Cell Planning
APN Access Point Name
BCCH Broadcast Control Channel
BCH Broadcast channel
BL Body Loss
BLER Block Error Rate
BW Bandwidth
CCCH Common Control Channel
CDF Cumulative Distribution Function
CDMA Code Division Multiple Access
CFI Control Format Indicator
CINR Carrier-to-Interference plus Noise Ratio
CP Cyclic Prefix
CW Continuous Wave
DCCH Dedicated Control Channel
DCI Downlink Control Information
DL Downlink
DL-SCH Downlink Shared Channel
DRS Demodulation Reference Signal
DTCH Dedicated Traffic Channel
DTM Digital Terrain Model
E-ICIC Enhanced Inter-Cell Interference Coordination
EIRP Effective Isotropic Radiated Power
EMM EPS Mobility Management
eNBs evolved Node Bs
EPC Evolved Packet Core
EPS Evolved Packet System
eRAN evolved Ran

xiii
E-UTRAN Evolved UMTs Terrestrial Radio Access Network
FDD Frequency-Division Duplex
FDMA Frequency Division Multiplexing Access
FFR Fractional Frequency Reuse
FTP File Transfer Protocol
GGSN Gateway GPRS Support Node
GGSN Gateway GPRS Support Node
GPRS General Packet Radio System
GSM Global System for Mobile
HARQ Hybrid Automation Repeat Request
HeNB Home eNB
HI Hybrid ARQ Indicator
HSS Home Subscriber Server
ICI Inter-Carrier Interference
ICIC Inter-Cell Interference Coordination
ID Identification
IM Interference Margin
IP Internet Protocol
Kbps Kilobits per second
KPIs Key Performance Indicators
LTE Long Term Evolution
LTE-A Long Term Evolution-Advance
MAC Medium Access Control
MAPL Maximum Allowed Path Loss
MBMS Multimedia Broadcast Multicast Service
Mbps Megabits per second
MCCH Multicast Control Channel
MCH Multicast Channel
MCS Modulation and Coding Schemes
ME Mobile Equipment
MIMO Multiple-Input Multiple-Output
MME Mobility Management Entity
MSs Mobile stations

xiv
MT Mobile Termination
MTCH Multicast Traffic Channel
NAS Non-Access Stratum Layer
NSN Nokia Simense Network
OBE Overbooking Factor
OFDM Orthogonal Frequency Division Multiplexing
OFDMA Orthogonal Frequency Division Multiplexing Access
PAPR Peak-to-Average-Power Ratio
PBCH Physical Broadcast Channel
PCCH Paging Control Channel
PCEF Policy Control Enforcement Function
PCFICH Physical Control Format Indicator Channel
PCH Paging Channel
PCRF Policy Control and charging Rules Function
PDCCH Physical Downlink Control Channel
PDCP Packet Data Convergence Protocol
PDN Packet Data Network
PDSCH Physical Downlink Shared Channel
PDUs Protocol Data Unit
Pen Loss Penetration Loss
PFR Partial Frequency Reuse
P-GW PDN Gateway
PHICH Physical Hybrid ARQ Indicator Channel
PHY Physical
PMCH Physical Multicast Channel
PRACH Physical Random Access Channel
PRBs Physical Resource Blocks
PSS Primary Synchronization Signal
PUCCH Physical Uplink Control Channel
PUSCH Physical Uplink Shared Channel
QAM Quadrature Amplitude Modulation
QoS Quality of Service
QPSK Quadrature Phase Shift keying

xv
RACH Random Access Channel
RAN Radio Access Network
RF Radio Frequency
RLC Radio Link Control
RRC Radio Resource Control
RRM Radio Resource Management
RS Reference Signal
RSRP Reference Signal Received Power
RX Receiver
SAE System Architecture Evolution
SC-FDMA Single Carrier FDMA
SDUs Service Data Units
SFR Soft Frequency Reuse
S-GW Serving Gateway
Sh Margin Shadowing Margin
SINR Signal to Interference pulse Noise Ratio
SM Session Management
SNR Signal to Noise Ratio
SON Self-Optimizing Networks
SRS Sounding Reference Signal
SSS Secondary Synchronization Signal
TBs Transport Blocks
TDD Time-Division Duplex
TE Terminal Equipment
TMA Tower-Mounted Amplifier
TX Transmitter
UCI Uplink Control Information
UE User Equipment
UICC Universal Integrated Circuit Card
UL Uplink
UL-SCH Uplink Shared Channel
UMTS Universal Mobile Telecommunication
USIM Universal Subscriber Identity Module

1
CHAPTER 1
INTRODUCTION
1.1 Introduction
The Long Term Evolution (LTE) & LTE-Advance (LTE-A) are rapid development of
wireless communication and multi-media applications such as Internet browsing, interactive
gaming, mobile TV, video streaming and audio streaming. The mobile communication
technology needs to meet different requirements of mobile data, mobile calculations and
mobile multi-media operations. In order to accommodate the increasing mobile data usage
and the new multimedia applications, the LTE and the LTE-A technologies have been
specified by the Third Generation Partnership Project (3GPP) as the emerging mobile
communication technologies for the next generation broadband mobile wireless networks [1].
The LTE system is designed to be a packet-based system containing less network elements,
which improves the system capacity and coverage. LTE system provides high performance in
terms of high data rates, low access latency, flexible bandwidth operation and seamless
integration with other existing wireless communication systems [2]. The LTE-A system
specified the 3GPP LTE Release 10 enhances the existing LTE systems to support much
higher data usage, lower latencies and better spectral efficiency. In addition, both of the LTE
and LTEA systems support flat IP connectivity, full interworking with heterogeneous wireless
access networks and many new types of base stations such as pico, femto base stations and
relay nodes in a macro-cellular network [1]. These and other significant performance
achievements rely on recently introduced physical layer technologies, such as Orthogonal
Frequency Division Multiplexing Access (OFDMA), Multiple-Input Multiple-Output
(MIMO) systems and smart antennas.
1.1.1 Background of Study
To address the growing demanded data capacity, the recent deployment of LTE has
highlighted the need and value of self-organizing capabilities within the network that permit
reductions in operational expenses during deployment as well as during continuing

2
operations. Self-optimizing capabilities in the network will lead to higher end user quality of
experience thus allowing for overall improved network performance [3].
3GPP initiated the work towards standardizing self-optimizing and self-organizing
capabilities for LTE, in Release 8 and Release 9. The standards provide network intelligence,
automation and network management features in order to automate the configuration and
optimization of wireless networks [4]. This effort has continued in Release 10 with additional
enhancements in each of the above areas and new areas allowing for inter-radio access
technology operation, enhanced Inter-Cell Interference Coordination (e-ICIC), coverage and
capacity optimization, energy efficiency and minimization of operational expenses through
minimization of drive tests [15].
Key Performance Indicators (KPI's) are indicators for if a device or equipment meets a
certain reliability criteria for being ready for deployment. The following KPI's are defined as
accessibility, retainability, integrity, availability and mobility [4].
1.1.2 Main Idea
To meet customer requirements for high-quality networks, the LTE trial networks must be
optimized during and after project implementation. Radio Frequency (RF) optimization is
necessary in the entire optimization process. Once LTE networks are deployed, they also need
to be optimized for service assurance, which translates to seamless connectivity and optimal
data rates. This process is fundamentally based on network analysis. It includes the gathering
of statistics and measurement results from the network management system. It allows the
provider to make the corrections and adjustments to the network.
1.1.3 Methodology
LTE is a new technology, largely in the state of standardization. Mostly, 3GPP
standardization documents and drafts have to be relied up on [1]. The work passed in several
steps:
 Preliminary study of the LTE.
 Specifications of the work area.
 Problem specific study and review of the related works.
 Theoretical understanding about input and output specifications.

3
 Work on LTE dimensioning and tool such as Nokia Simense Network (NSN) and
ATOLL simulation software.
 Calculate the coverage and capacity planning to estimate the number of sites.
 Drive test results (such as service drop points and handover failure points) in the
current area.
 Reference Signal Received Power (RSRP) coverage diagram.
 Signal to Interference plus Noise Ratio (SINR) distribution diagram.
 Measured handover success rates.
 Areas to be optimized can be determined by comparing the distribution of RSRPs,
SINRs, and handover success rates with the optimization baseline.
Finally, this step is done for Taiz urban area by using ATOLL simulation software.
1.2 Statement of Problem
After the completion of all steps of planning for the wireless communications network
(coverage and capacity) and the creation of the network infrastructure at the target urban area
in Taiz city, many of the problems are affecting the performance of the network. The first
problem relates to the used techniques and devices. The other problem relates to the
geographical nature of the area where it is continuously changing, for example, buildings and
streets.
Base on the mentioned two problems, the KPI of the network will not be compatible with
the specifications and standards that have been identified in advance by the operator for each
coverage, capacity and quality. Also the KPI may be far from the standards defined by the
local authorities. Optimization of RF is still the most important challenges facing any wireless
communication network.
1.3 Objectives
The overall objective of this project is to optimize the LTE network after the planning
process. Radio network optimization involves the activities such as data collection and data
analysis of the implemented network and checking of the causes which affect the network
operation quality. By modifying the parameters and some methods, the network optimization

4
ensures that the network performance and resources are optimized and provides appropriate
suggestions for future network maintenance and planning.
The objectives of this project can be summarized as:
- To analyze the implemented LTE network in the urban area at Taiz city.
- To optimize the overall performance of the proposed LTE network.
- To investigate the quality of the optimized LTE network by achieving the required
KPI.
1.4 Scope of Study
This report will views and discussed the project according to the following points:
 The basics concepts of LTE system are reviewed.
 The LTE network is planned and then optimized in the urban areas at Taiz city.
 The optimization for coverage and capacity of the proposed LTE network is analyzed
by ATOLL simulation software.
 The target KPI must be achieved for the proposed LTE network.
 Finally, the report is concluded.
1.5 Report Outline
The remaining of this project report includes four chapters as follows:
CHAPTER 2: LITERATURE REVIEW:
We discussed the LTE architecture and LTE layers. There are two duplexing in LTE
system FDD and TDD duplexing. LTE uses three types of modulation QPSK, 16-QAM, 64-
QAM. The new techniques used in LTE are MIMO technique, OFDMA technique in the
downlink and SC-FDMA technique in the uplink. Additionally, described the ICIC
Technology. Then, the main topic of this the planning of coverage and capacity are used for
calculate the number of site in network. Finally we discussed the LTE optimization.
CHAPTER 3: METHODOLOGY:
We discussed the planning of LTE FDD duplexing starting from the coverage planning to
optimization of the system. The new techniques in LTE system increase coverage and
throughput of the system. Simulations for planning LTE network by Atoll program were

5
performed on. The total numbers of cells are 95 cells in 2110 MHZ frequency band, 95 cells
operating on 20 MHZ channel bandwidth.
CHAPTER 4: RESULTS:
We discussed the optimization to increase cell edge throughput, signal level, coverage and
reduce overlapping between cell by using some manner, such as ACP, AFP, Monte- Carlo
algorithm and neighbor planning.
CHPATER 5: CONCLUSIONS AND FUTURE WORKS:
We summarize the conclusions of the thesis and refer to the recommended future work.
The thesis is terminated with the references.

6
CHAPTER 2
LITERATURE REVIEW
2.1 Introduction
This chapter describes the basic functionality of an evolved packet system (EPS) network,
the technologies and planning behind it. First, a quick look on the background and
standardization is given. Next the network architecture, the interfaces and protocols between
the elements are discussed. Then the technologies MIMO, OFDMA, and Single Carrier
FDMA (SC-FDMA); and its bandwidth (BW) are discussed. Finally, the planning (of
coverage and capacity) is presented.
2.2 Architecture of LTE
Figure 2.1 reviews the high-level architecture of the evolved (EPS). There are three main
components, namely the user equipment (UE), the evolved Universal Mobile
Telecommunication System (UMTS) terrestrial radio access network (E-UTRAN) and the
evolved packet core (EPC). The interfaces between the different parts of the system are
denoted Uu, S1 and SGi [2].
Figure 2.1: The EPS network elements.

7
Table 2.1: The LTE UE categories
Class 1 Class 2 Class 3 Class 4 Class 5
Peak rate
DL/UL
10/5
Mbps
50/25 Mbps 100/50
Mbps
150/50
Mbps
300/75
Mbps
RF bandwidth 20 MHz 20 MHz 20 MHz 20 MHz 20 MHz
Modulation DL 64QAM 64QAM 64QAM 64QAM 64QAM
Modulation UL 16QAM 16QAM 16QAM 16QAM 64QAM
Rx diversity Yes Yes Yes Yes Yes
BS Tx diversity 1-4 Tx 1-4 Tx 1-4 Tx 1-4 Tx 1-4 Tx
MIMO DL Optional 2x2 2x2 2x2 4x4
2.2.1 User Equipment (UE)
The internal architecture of the UE is identical to a Mobile Equipment (ME). The ME
comprises of the following important modules:
 Mobile Termination (MT): This handles all the communication functions.
 Terminal Equipment (TE): This terminates the data streams.
 Universal Integrated Circuit Card (UICC): This is also known as the SIM card for
LTE equipment. It runs an application known as the Universal Subscriber Identity
Module (USIM) [5].
To support different hardware capabilities, different user equipment categories or classes
are defined as shown in Table 2.1. The categories are distinguished through the maximum
supported data rates for downlink and uplink. In addition, the maximum number of data layers
(or streams) may differ depending on UE category [6].
2.2.2 The Access Network
The access network of the LTE, E-UTRAN, simply consists of a network of evolved
nodeBs (eNBs), as illustrated in Figure 2.1. The eNBs are normally inter-connected with each

8
other by means of an interface known as X2, and to the EPC by means of the S1 interface –
more speciﬁcally, to the MME by means of the S1-MME interface and to the S-GW by means
of the S1-U interface. The E-UTRAN provides air-interface user-plane and control-plane
protocol management for the users. It supports the following functions: radio resource
management, measurements, access-stratum security, IP header compression and encryption
of the user data stream, MME election, user-plane data routing to the S-GW, scheduling and
transmission of paging messages, broadcast information, and public warning system messages
[2].
The use of small cells is becoming increasingly important due to their ability to provide
increased system capacity compared to a homogeneous network of macrocells. Small cells
can generally be characterized as either picocells controlled by a pico eNodeB, or femtocells,
controlled by a Home eNB (HeNB) [7].
2.2.3 The Core Network
The EPC is responsible for the overall control of the UE and the establishment of the
bearers. The main logical nodes of the EPC are:
 Mobility Management Entity (MME).
 Serving Gateway (S-GW).
 Packet Data Network (PDN) Gateway (P-GW).
Below is a brief description of each of the components shown in the above architecture [8]:
 The MME controls the high-level operation of the mobile by means of signaling
messages and Home Subscriber Server (HSS(.
- HSS component has been carried forward from (UMTS) and Global System for
Mobile (GSM) and is a central database that contains information about all the
network operator's subscribers.
 The S-GW acts as a router, and forwards data between the base station and the PDN
gateway.
 The P-GW communicates with the outside world which is the PDN, using SGi
interface. Each packet data network is identified by an Access Point Name (APN(. The
PDN gateway has the same role as the General Packet Radio System (GPRS) support
node (GGSN) and the serving GPRS support node (SGSN) with UMTS and GSM.

9
 The Policy Control and Charging Rules Function (PCRF) are responsible for policy
control decision-making, as well as for controlling the flow-based charging
functionalities in the Policy Control Enforcement Function (PCEF) which resides in
the P-GW. The PCRF provides the QoS authorization.
2.2.4 The Interfaces
Along with the air interface treated in the next section there are two other interfaces of
interest from the radio point of view:
 X2 interface
Logical interface between eNodeBs since it does not need direct site-to-site
connection. It can be routed via core network as well. It is used during inter
eNodeB handovers avoiding the involvement of the core network during the
handover and forwarding the data between source and target eNodeB. It is also
involved in the radio resource management (RRM) functions like e.g. exchange of
load information between neighbouring eNodeBs to facilitate the interference
management.
 S1 interface
The S1 interface is divided in two interfaces:
o S1-U interface: User plane interface between the eNodeB and the S-GW
Dedicated only to user data.
o S1-MME interface: Control plane interface between the eNodeB and the
MME for the exchange of non-access stratum messages between MME and
UE (e.g. paging, tracking area updates, and authentication(.
2.3 LTE Radio Interface Architecture
The radio interface in LTE is developed according to the requirements of spectrum
flexibility, spectrum efficiency and cost effectiveness, robustness against time dispersion has
influenced the choice of transmission technique in both UL and DL.The EPS bearer is carried
by the E-UTRAN radio bearer service in the radio interface. The E-UTRAN radio bearer is
carried by the radio channels. The radio channel structure is divided into logical, transport and

10
physical channels. The logical channels are carried by transport channels, which in turn are
carried by the physical channels as illustrated in Figure 2.2 [7]. The main functionalities
carried out in each layer are summarized in the following sections:
2.3.1 Non-Access Stratum Layer (NAS)
The NAS consists of the Session Management (SM), EPS Mobility Management (EMM)
and NAS security layers. The following are examples of functions are performed by NAS :
 Mobility management for idle UEs.
 UE authentication.
 EPS bearer management.
 Configuration and control of security.
 Paging initiation for idle UEs.
Figure 2.2: LTE protocol stack.

11
The NAS messages are transported by the Radio Resource Control (RRC) layer. There are
two ways to transport the NAS messages by RRC, either by concatenating the NAS messages
with other RRC messages, or by including the NAS messages in dedicated RRC messages
without concatenation [9].
2.3.2 Radio Resource Control Layer (RRC)
The RRC manages the radio resources of the UE and the eNodeB use. It is extremely
important from the mobility point of view, since it provides the management tools and
information required for handover and cell selection [9].
2.3.3 Packet Data Convergence Protocol Layer (PDCP(
This layer processes the RRC messages in the control plane and Internet Protocol (IP)
packets in the user plane. Depending on the radio bearer, the main functions of the PDCP
layer are header compression, security (integrity protection and ciphering), and support for
reordering and retransmission during handover. For radio bearers which are configured to use
the PDCP layer, there is one PDCP entity per radio bearer [7].
2.3.4 Radio Link Control Layer (RLC)
The main functions of the RLC layer are segmentation and reassembly of upper layer
packets in order to adapt them to the size which can actually be transmitted over the radio
interface. For radio bearers which need error-free transmission, the RLC layer also performs
retransmission to recover from packet losses. Additionally, the RLC layer performs reordering
to compensate for out-of-order reception due to Hybrid Automatic Repeat request (HARQ)
operation in the layer below. There is one RLC entity per radio bearer [7].

12
2.3.5 Medium-Access Control layer (MAC)
The MAC layer is the lowest sub-layer in the Layer 2 architecture of the LTE radio
protocol stack. The connection to the physical layer below is through transport channels, and
the connection to the RLC layer above is through logical channels. The MAC layer therefore
performs multiplexing and de-multiplexing between logical channels and transport channels.
The MAC layer in the transmitting side constructs MAC Protocol Data Unit (PDUs), known
as Transport Blocks (TBs), from MAC Service Data Unit (SDUs) received through logical
channels. In the receiving side, the MAC layer recovers MAC SDUs from MAC PDUs
received through transport channels [7].
The MAC layer provides a data transfer service for the RLC layer through logical
channels, which are either Control Logical Channels (for the transport of control data such as
RRC signaling), or Traffic Logical Channels (for user plane data). These are listed in Table
2.2 [2].
Table 2.2: Logical channels of the LTE
DirectionInformation carriedNameReleaseChannel
UL, DLUser plane dataDedicated traffic channelR8DTCH
UL, DLSignaling on SRB 1 & 2Dedicated control channelR8DCCH
UL, DLSignaling on SRB 0Common control channelR8CCCH
DLPaging messagesPaging control channelR8PCCH
DLSystem informationBroadcast control channelR8BCCH
DLMBMS signalingMulticast control channelR8MCCH
DLMBMS dataMulticast traffic channelR9MTCH
Table 2.3: Transport channels of the LTE
ULUplink data and signallingUplink shared channelR8UL-SCH
ULRandom access requestsRandom access channelR8RACH
DLDownlink data and signallingDownlink shared
channel
R8DL-SCH
DLPaging messagesPaging channelR8PCH
DLMaster information blockBroadcast channelR8BCH
DLMBMSMulticast channelR8/R9MCH

13
Table 2.4: Physical channels of the LTE
ULUL-SCH and/or UCIPhysical uplink shared channelR8PUSCH
ULRACHPhysical random access channelR8PRACH
DLDL-SCH and PCHPhysical downlink shared channelR8PDSCH
DLBCHPhysical broadcast channelR8PBCH
DLMCHPhysical multicast channelR8/R9PMCH
ULUCIPhysical uplink control channelR8PUCCH
DLCFIPhysical control format indicator
channel
R8PCFICH
DLHIPhysical hybrid ARQ indicator
channel
R8PHICH
DLDCIPhysical downlink control channelR8PDCCH
Data from the MAC layer is exchanged with the physical layer through transport channels.
Data is multiplexed into transport channels depending on how it is transmitted over the air.
The transport channels are listed in Table 2.3 [2].
2.3.6 Physical Layer (PHY)
The physical layer is responsible for coding, PHY_HARQ processing, modulation, multi-
antenna processing, and mapping of the signal to the appropriate physical time–frequency
resources. It also handles mapping of transport channels to physical channel. The physical
layer provides services to the MAC layer in the form of transport channels. Data transmission
in downlink and uplink use the DL-SCH and UL-SCH transport-channel types respectively.
A physical channel with a corresponding transport channel, there are also physical
channels without a corresponding transport channel. These channels, known as L1/L2 control
channels, are used for downlink control information (DCI), providing the terminal with the
necessary information for proper reception and decoding of the downlink data transmission,
and uplink control information (UCI) used for providing the scheduler and the hybrid-ARQ
protocol with information about the situation at the terminal [10]. The physical channels are
listed in Table 2.4 [2].
The final information streams are the physical signals, which support the lowest-level
operation of the physical layer. In the uplink, the mobile transmits the demodulation reference
signal (DRS) at the same time as the Physical uplink shared channel (PUSCH) and Physical

14
uplink control channel (PUCCH), as a phase reference for use in channel estimation. It can
also transmit the sounding reference signal (SRS) at times configured by the base station, as a
power reference in support of frequency-dependent scheduling.
The downlink usually combines these two roles in the form of the cell specific reference
signal (RS). The UE specific reference signals are less important and are sent to mobiles that
are using beamforming in support of channel estimation. The specifications introduce other
downlink reference signals as part of Releases 9 and 10. The base station also transmits two
other physical signals, which help the mobile acquire the base station after it first switches on.
These are known as the primary synchronization signal (PSS) and the secondary
synchronization signal (SSS).
2.4 Technologies for LTE
2.4.1 MIMO Transmission
Multiple antenna solutions can be used in order to increase the spectrum efficiency as well
as the peak data rates. Different approaches aim for different purposes, e.g. traditional
beamforming and transmitter diversity techniques increase the coverage and capacity. Spatial
multiplexing, a technique which requires multiple antennas at both transmitter and receiver,
increases the peak data rates and spectrum efficiency up to several hundred percent, is shown
in Figure 2.3.
Figure 2.3: MIMO technology.

15
There use of multiple antennas to improving the Signal to Noise Ratio (SNR). This means
where the SNR is low, improving the SNR is the way to go. This can be achieved by the use
of beamforming, transmitter (Tx) diversity and/or receiver (Rx) diversity. Beamforming
concentrates the transmitted (and/or received) energy in desired direction(s). Tx diversity
achieves diversity against the channel fading by transmitting the information at different times
and/or from different antenna locations. Open Loop Tx diversity does not exploit any channel
information (no feedback from receiver) while closed loop Tx diversity uses feedback from
the UE in order to maximize the performance. When the SNR is high, the data rate and
spectrum efficiency can be increased such as increasing the modulation order (e.g. going from
16-QAM to 64-QAM). This gives us more bits/s/Hz. However, the improvement in
throughput and spectrum efficiency as a function of the SNR is logarithmic. This means that
the throughput saturates at high SNRs, resulting in an excessive need for power/link budget in
order to reach high data rates [7].
For LTE MIMO, multiple antenna technology opens the door to a large variety of features,
but not all of them easily deliver their theoretical promises when it comes to implementation
in practical systems. Multiple antennas can be used in a variety of ways, mainly based on
three fundamental principles [7]:
• Diversity gain: Use of the spatial diversity provided by the multiple antennas to improve
the robustness of the transmission against multipath fading.
• Array gain: Concentration of energy in one or more given directions via precoding or
beamforming. This also allows multiple users located in different directions to be served
simultaneously (so-called multi-user MIMO).
• Spatial multiplexing gain: Transmission of multiple signal streams to a single user on
multiple spatial layers created by combinations of the available antennas.
Figure 2.4: Flexibility in duplex arrangement: FDD and TDD.

16
2.4.2 Spectrum Flexibility
A high degree of spectrum flexibility is one of the main characteristics of the LTE radio-
access technology. The aim of this spectrum flexibility is to allow for the deployment of LTE
radio access in difference frequency bands with different characteristics, including different
duplex arrangements and different sizes of the available spectrum. One important part of
the LTE requirements in terms of spectrum flexibility is the possibility to deploy LTE-
based radio access in both paired and unpaired spectrum. Therefore, LTE supports both
frequency- and time-division-based duplex arrangements, as illustrated in Figure 2.4.
Frequency-Division Duplex (FDD) implies that downlink and uplink transmission take place
in different and sufficiently separated frequency bands. The Time-Division Duplex (TDD),
implies that downlink and uplink transmission take place in different and non-overlapping
time slots. Thus, the TDD can operate in unpaired spectrum, whereas the FDD requires paired
spectrum [11]. One important part of the LTE requirements in terms of spectrum flexibility is
the possibility to deploy LTE-based radio access in both paired and unpaired spectrum.
Therefore, LTE supports both frequency- and time-division-based duplex arrangements, as
illustrated in Figure 2.4. Frequency-Division Duplex (FDD) implies that downlink and uplink
transmission take place in different and sufficiently separated frequency bands. The Time-
Division Duplex (TDD), implies that downlink and uplink transmission take place in different
and non-overlapping time slots. Thus, the TDD can operate in unpaired spectrum, whereas the
FDD requires paired spectrum [11].
The LTE also supports half-duplex FDD at the terminal (illustrated in the middle of Figure
2.4). In half-duplex FDD, transmission and reception at a specific terminal are separated in
both frequency and time. The base station still uses full-duplex FDD as it simultaneously may
schedule different terminals in uplink and downlink. The main benefit with half-duplex FDD
is the reduced terminal complexity as no duplex filter is needed in the terminal [11].
2.4.3 Bandwidth Flexibility
An important characteristic of the LTE is the possibility for different transmission
bandwidths on both downlink and uplink. The main reason for this is that the amount of
spectrum available for LTE deployment may vary significantly between different frequency
bands. Furthermore, the possibility of operating in different spectrum allocations gives the
possibility for gradual migration of spectrum from other radio-access technologies to LTE.

17
The LTE supports operation in a wide range of spectrum allocations, achieved by a flexible
transmission bandwidth being part of the LTE specifications. To efficiently support very high
data rates when spectrum is available, a wide transmission bandwidth is necessary [11].
2.4.4 Transmission Schemes
2.4.4.1 OFDMA
The basic idea of Orthogonal Frequency Division Multiplexing (OFDM) is to distribute the
sent data to multiple narrow, frequency separated carriers. The concept is close to the
Frequency Division Multiple Access (FDMA). The difference is that the carriers in OFDM
actually overlap each other in the frequency domain, allowing for a much more efficient usage
of the spectrum. Since a time domain rectangular waveform corresponds to a sinusoidal wave
in the frequency domain, the carriers may be spaced so that at the sampling instant of each
carrier the others have a zero value [11].
In addition to the efficient spectrum usage, the OFDM method has also other advantages. It
is resilient against frequency selective fading, since the fading might disturb only a few
carriers while others remain unaffected. Consequently, it allows the usage of frequency
domain scheduling, that is, scheduling the users to the best quality carriers. The bandwidth
may also be increased simply by adding more carriers, without adding large amounts of
complexity to the receiver implementation.
The OFDMA in the LTE uses the OFDM concept, but rather than giving the whole
bandwidth to a one user at a time, multiple simultaneous users are allocated to different
subcarriers. The principle is shown in Figure 2.5.
Figure 2.5: OFDMA downlink multiple access.
Sub-carriers
Sub-frame
Frequency
Time
Time frequency
resource for User 1
Time frequency
resource for User 2
Time frequency
resource for User 3
System Bandwidth

18
The subcarriers are separated by 15 kHz distance in frequency domain. The OFDMA
allows for flexibility in the transmission bandwidth, and LTE is currently specified for
bandwidths of 1.4, 3, 5, 10, 15 and 20 MHz. In release 10 aggregating multiple carriers will
be possible in order to increase the bandwidth if desired. Although the OFDMA has good
spectral properties and resilience against fading, it also has its share of difficulties. As the
orthogonally of the subcarriers depends heavily on the accuracy of the frequency, the
OFDMA is vulnerable to Doppler shifts and local oscillator inaccuracies. However, the 15
kHz subcarrier separation is dimensioned to be sufficient to alleviate these phenomena. A
more severe problem is the high Peak-to-Average-Power Ratio (PAPR) of the OFDMA
signal, which causes difficulties for the amplifier design of the transmitter. High PAPR causes
the transmitter to consume more power, and also makes it more expensive due to power
amplifier linearity requirements. These were the main reasons for not choosing OFDMA as
the technology for the uplink multiple accesses [12].
2.4.4.2 SC-FDMA
Because of the problems described in the previous section, OFDMA was unfit to be used
as the uplink transmission scheme. The multi carrier type of transmission would not work, so
the 3GPP ended up with another kind of scheme which is a Single Carrier FDMA (SC-
FDMA) [12].
In contrast to the OFDMA, the SC-FDMA employs a single carrier transmission scheme.
However, the subcarrier structure is the same as in the OFDMA, and the data is still scheduled
using multiple resource blocks and subcarriers. Instead of changing the subcarrier structure,
some changes are introduced into the transmitter to produce a single carrier transmission.
While in the OFDMA the data symbols are divided into many subcarriers and sent at a
relatively low rate at the same time, the idea of the SC-FDMA is to send the symbols one
after another, but with a high rate. This avoids summing up many independent signals, since
the modulation symbols are sent one at a time. Figure 2.6 illustrates this procedure. If the
terminal is scheduled additional resource blocks, it just increases its sending rate rather than
sending the data in parallel frequencies as in the OFDMA [12].

19
Figure 2.6: Transmission of 4 modulation symbols using OFDMA and SC-FDMA.
Table 2.5: Number of PRBs for the allocated bandwidths
Bandwidth (MHz) 1.4 3 5 10 15 20
Number of PRBs 6 15 25 50 75 100
2.4.4.3 Frame Structure and Scheduling
As mentioned above, the resources are scheduled to the users in blocks of data referred to
as Physical Resource Blocks (PRBs). A PRB consists of 12 subcarriers each sending 6 or 7
modulation symbols in a time of 0.5 ms. Six symbols are sent if the extended Cyclic Prefix
(CP) is used, since the longer prefixes take space from the symbols. Seven symbols is the
normal case used with the normal CP. The dimensions of the resource block are independent
of the bandwidth used, so a 5 MHz band and a 20 MHz band both use the 12 carrier
PRBs.However, the number of resource blocks available for scheduling naturally depends on
the carrier bandwidth. This dependency is summarized in Table 2.5 [12].
2.5 Inter-Cell Interference Coordination (ICIC) Technology
The LTE is designed for frequency reuse 1 to maximize (spectrum efficiency), which
means that all the neighbor cells are using same frequency channels and therefore there is no
cell-planning to deal with the interference issues.
There is a high probability that a resource block scheduled to cell edge user, is also being
transmitted by neighbor cell, resulting in high interference, eventually low throughput or call

20
drops, as shown in Figure 2.7. Traffic channel can sustain up to 10% of Block Error Rate
(BLER) in low Signal-to-Interference plus Noise Ratio (SINR) but control channels cannot
sustain up [11]. The ICIC is introduced in 3GPP release 8 to deal with interference issues at
cell-edge, the ICIC mitigates interference on traffic channels only and it uses power and
frequency domain to mitigate cell-edge interference from neighbor cells.
There are three schemes of ICIC can be reviewed as [13]:
1. One scheme of ICIC is where neighbor eNBs use different sets of resource blocks
throughout the cell at given time i.e. no two neighbor eNBs will use same resource
assignments for their UEs. This greatly improves cell-edge SINR. The disadvantage is
decrease in throughput throughout the cell, since full resources blocks are not being
utilized.
2. In the second scheme, all eNBs utilize complete range of resource blocks for centrally
located users but for cell-edge users, no two neighbor eNBs uses the same set of resource
blocks at given time.
3. In the third scheme (probably the preferred scheme), all the neighbor eNBs use different
power schemes across the spectrum while resource block assignment can be according to
second scheme explained above. For example, eNB can use power boost for cell edge
users with specific set of resources (not used by neighbors), while keeping low signal
power for center users with availability of all resource blocks.
One of the fundamental techniques to deal with the Inter-Carrier Interference (ICI)
problem is to control the use of frequencies over the various channels in the network.
Frequency reuse-based schemes include: conventional frequency planning schemes (Reuse-1
and Reuse-3) and fractional frequency reuse (FFR);
• Conventional Frequency Planning Schemes (Reuse-1 and Reuse-3)
This is simplest scheme to allocate frequencies in a cellular network by using reuse factor
of as shown in Figure 2.8 (a) which leads to high peak data rates. However, in this case,
higher interference is observed on cell edges. The classical interference management is done
by using reuse ratio 3 as shown in Figure 2.8 (b), by using this interference is low but large
capacity loss because only one third of resources are used in each cell [13].

21
Figure 2.7: Inter-Cell Interference Coordination (ICIC) Technology.
Figure 2.8: Frequency reuse schemes.
• Fractional Frequency Reuse (FFR)
To avoid the shortcomings of the conventional frequency reuse schemes, the fractional
frequency reuse (FFR) scheme is introduced to achieve a FFR between 1 and 3. FFR divides
the whole available resources into two subsets or groups, namely, the major group and the
minor group. The former is used to serve the cell-edge users, while the latter is used to cover
the cell-center users. Generally speaking, the FFR scheme can be divided into two main
classes which are show in Figure 2.9.
i. Soft Frequency Reuse (SFR): the cell area is divided into two regions; a central region
where the entire frequency band is available and a cell edge area where only a small
fraction of the spectrum is available. The spectrum dedicated for the cell edge may also
be used in the central region if it is not being used at the cell edge. This is overcome by
allocating high power carriers to the users in this region thus improving the SINR.
ii. Partial Frequency Reuse (PFR): in these schemes a common frequency band is used in all
sectors with equal power, while the power allocation of the remaining sub-bands is
coordinated among the neighboring cells in order to create one sub-band with a low inter-
cell interference level in each sector [13].

22
Figure 2.9: Static partition based schemes.
2.6 Network Planning
The main aim of radio network planning is to provide a cost effective solution for the radio
network in terms of coverage, capacity and quality. Utilizing the available limited bandwidth
very preciously so as to cater to millions in a vast area with good quality, coverage, and
without interference using ATOLL planning tool is the cream of this project [8].
2.6.1 LTE Dimensioning Process
The typical Network requirements that make up the input to the dimensioning process are;
coverage area, number of subscribers, traffic model and UL/DL cell edge throughput. There
are a number of ways to dimension the LTE network to meet these requirements. Figure 2.10
illustrated one LTE dimensioning process that can be followed to produce a final site count
that meets the uplink and downlink coverage and capacity requirements [14, 15].
In a detailed LTE radio network dimensioning procedure (capacity and coverage analysis
link budget preparation link and system level simulation) has been performed in order to
prepare a radio planning guideline considering possible network implementation in Taiz city
[14].
2.6.2 LTE Coverage Process
The main aim of coverage planning is to estimate the coverage distance of a BS with
parameter settings derived from actual cell boundary coverage requirements sequentially to
meet network size requirements. Planning strategies for LTE system coverage can be
classified into uplink edge and downlink edge, uplink edge is essentially applied in coverage.

23
Figure 2.10: LTE dimensioning process.
The uplink coverage radius is calculated using the received power from users to base
station and link budget parameters, then the down link edge is based on the received power at
the users from donor and the interferences power from neighbors cell .
Link budget and coverage planning is calculated, for both cases UL and DL as
following the procedure steps are [16]:
• Step 1: Calculate the Max Allowed Path Loss (MAPL) for DL and UL.
• Step 2: Calculate the DL and UL cell radiuses by the propagation model equation
and the MAPL.
• Step 3: Determine the appropriate cell radius by balancing the DL and UL radiuses.
• Step 4: Calculate the site coverage area and the required sites number.
2.6.2.1 Radio Link Budget
The link budget calculations estimate the maximum allowed signal attenuation,
called path loss, between the mobile and the base station antenna. The maximum path loss
allows the maximum cell range to be estimated with a suitable propagation model, such
as Okumura–Hata. The cell range gives the number of base station sites required to cover the
target geographical area. The link budget calculation can also be used to compare the relative
coverage of the different systems [14]. A link budget scheme is shown in Figure 2.11.

24
Table 2.6: Example for a link budget of downlink
Table 2.7: Site coverage areas and inter-site distance
* Omni 2-sectors 3-sectors
Site area
Inter-site distance
Figure 2.11: Link budget scheme.
Parameter Value Comment
A Max eNB TX power 46 dBm
B Cable loss 3 dB
C TMA loss 1 dB
D eNB antenna gain max 19 dB
E EIRP max 61 dBm = A – B – C + D
BW RX 1.8 MHz
F Noise power -102 dBm
G SNIR min 5 dB
H UE antenna gain 0 dBi
I Min required RX power -97 dBm = F + G – H
J Total path loss 158 dBm = E – I
K Other gains ,losses, margins - 10 dB Shadowing, fast fading, multi-
antenna
L Maximum Allowed
Propagation Loss
148 dBm = J + K
Cell range 3.5 km

25
Propagation data is included in the calculation such as penetration loss (Penloss), Fading
Margin, and Gain against Shadowing (shMargin). The interference margin (IM) and the body
loss (BL) are also considered, so the maximum propagation loss is given by:
( ) ( )
( )
2.6.2.2 Propagation Model
A propagation model describes the average signal propagation, and it converts the
maximum allowed propagation loss to the maximum cell range. It depends on [3]:
 Environment: urban, rural, dense urban, suburban, open, forest or sea.
 Distance.
 Frequency.
 Atmospheric conditions.
 Indoor/outdoor [16].
Table 2.6 summarizes the main features for a link budget of downlink as example.
2.6.2.3 Site Coverage Area and Inter-Site Distance
After determination of cell range (radius) we can estimate the site coverage area as the
following equation [3]:
( ) ( )
Table 2.7 shows an example for that.
2.6.3 LTE Capacity Planning
Capacity planning gives an estimate of the resources needed for supporting a specified
offered traffic with a certain level of QoS (e.g. throughput or blocking probability).
Theoretical capacity of the network is limited by the number of eNBs installed in the network.
Cell capacity in the LTE is impacted by several factors, which includes interference level,
packet scheduler implementation and supported modulation and coding schemes. Capacity
requirements are set forth by the network operators based on their predicted traffic. Average

26
cell throughput is needed to calculate the capacity-based site count. The main indicator of
capacity is SINR distribution in the cell. The SINR distribution can be directly mapped to the
system capacity (data rate). The capacity based on the number of sites is compared with the
result of the coverage and the larger of the two numbers is selected as the number of end sites
[14]. Table 2.8 shows the cell average throughputs for different LTE networks with different
bandwidth.
Traffic model provides the parameter Share of Active Subscribers [%] standing for the
amount of subscribers being active during the busy hour by the following equation [14]:
( )
Table 2.9 gives the maximum number of active users per cell at different bandwidth.
The number of sites (#sites) can be calculated as:
( )
Cell capacity provided from the link level simulation as input to these approaches. The
target date rate also is assumed as #Mbps per subscriber. Since only some of the subscribers
are downloading data simultaneously, an overbooking factor can be used to calculate the
overall data as following [17].
( )
( )
The overbooking factor (OBF) is the average number of users that can share a given
unit of channel.
Table 2.8 LTE 2600 MHz cell average throughput with different bandwidth
Frequency Bandwidth Scenario Cell Average Throughput
DL(Mbps) UL(Mbps)
2100 MHz
5 MHz Urban 8.173 4.715
Suburban 6.266 3.342
10 MHz Urban 16.918 9.761
Suburban 12.971 6.918
15 MHz Urban 25.546 14.739
Suburban 19.587 10.446
20 MHz Urban 34.344 19.814
Suburban 26.332 14.044

27
Table 2.9 Maximum number of active users per cell
2.7 LTE Optimization
An LTE network will have to be optimized after deployment to provide better coverage,
throughput, lower latency and seamless integration as the specification asks for. Based on the
collected data, RF planning engineers analyze the performance and may be decide to
reconfiguration more eNBs and optimization the network by using some manner that
discussed at the following sections.
2.7.1 LTE Key Performance Indicators (KPIs)
With the initial target of downlink peak data rate reaching above 100 Mbit/s, the next-
generation LTE system is developed to meet the increasing demands on higher data rate due
to fast expansion of multimedia applications. For a new wireless system like the LTE, a set of
KPIs are defined for the evaluation of system performance, in particular the performance of
the evolved Radio Access Network (eRAN).
The measurement is made in terms of cells. The KPI value reflects the performance in a
cell or a cluster. The associated counters can be obtained from cell statistics. As LTE is still a
developing technology, it is important to note that as more field trials are carried out and
results validated against LTE network performance goals. The design targets outlined in this
section are subject to change.
The quality of the LTE RF design will be evaluated using Atoll. This will be based on a
combination of area predictions and Monte Carlo simulations. It is important to note that the
emphasis of the design evaluation will be on focusing where demand is and where potential
LTE users are located. The following KPIs are anon comprehensive list of key performance
indicators that will be used to validate the quality of the LTE RF network design.
The KPIs are classified into categories based on the measurement targets: accessibility,
retainability, mobility, service integrity, utilization, availability, and traffic KPIs which are
described as show the following:
Bandwidth 5 MHz 10 MHz 20 MHz
Maximum number of active
users per cell
50 100 200

28
1. Accessibility KPIs: are used to measure the probability whether services requested by
a user can be accessed within specified tolerances in the given operating conditions.
Accessibility KPIs are also used to evaluate accessibility provided by EPS and
network performance such as RRC Setup Success Rate (Service), RRC Setup Success
Rate (Signaling), RRC Setup Success Rate (VoIP) and Call Setup Success Rate.
2. Retainability KPIs: are used to evaluate the network capability to retain services
requested by a user for a desired duration once the user is connected to the services
such as Call Drop Rate (VoIP) and Service Drop Rate.
3. Mobility KPIs: are used to evaluate the performance of E-UTRAN mobility, which
are critical to the customer experience such as Intra-frequency Handover Success
Rate and Inter-frequency Handover Success Rate.
4. Service Integrity KPIs: are indicated the E-UTRAN impacts on the service quality
provided to the end user such as Service downlink and uplink average throughput and
cell downlink and uplink average throughput.
5. Utilization KPIs: are used to evaluate the capability to meet the traffic demand and
other characteristics in specific internal conditions such as Resource Block utilizing
rate.
6. Availability KPIs: is the percentage of time that a cell is available. A cell is available
when the eNodeB can provide EPS bearer services.
7. Traffic KPIs: are used to measure the traffic volume on the LTE (RAN). Based on
traffic types, the traffic KPIs are classified into three categories: radio bearers,
downlink traffic volume, and uplink traffic volume [23].
Definition the KPIs parameters by using eNodeB system and definition the performance of
KPIs based on vendors promise. Verification of KPIs target values that demand from vendor
by using planning and dimensioning tools, either the results KPIs tune with the vendor KPIs
or we will optimize the network parameters unto questioning the vendors KPIs. But defining
KPI and parameter planning has been considered out of the scope of this project.
2.7.2 Network Optimization
Network optimization is a process to improve the overall network quality as experienced by
the mobile subscribers and to ensure that network resources are used efficiently.
Optimization includes:

29
1. Performance measurements.
2. Analysis of the measurement results.
3. Updates in the network configuration and parameters.
The measurements can be obtained from the test mobile and from the radio network
elements. The LTE mobile can provide relevant measurements such as uplink transmission
power, handover rate and downlink BLER. The network performance be will observed when
the network load is high [25].
LTE provides some network self-optimization tools which can be used to optimize some
aspects of the network configuration automatically. These tools are collectively known as
self-optimizing networks (SON). By using this technique, a base station can gather
information about any problems that have arisen due to the use of unsuitable measurement
reporting thresholds. It can then use the information to adjust the thresholds which are used
and to correct the problem.
2.7.2.1 Optimization Procedures
The suitable preamble formats are selected based on many factors: traffic type, dynamic
adjusting of the broadcast power control parameter, antenna type, antenna height, antenna tilt,
antenna azimuth, feeder type, and feeder length. By selecting the most suitable preamble
format, the access success rate can be optimized while it still maintaining a low interference
level. This results in best user experience with fast access and best possible throughput [24].
The technology-specific integration of the optimization procedures with the simulation
platform is shown in Figure 4.1 and described in this section. Within each Monte Carlo
snapshot, the throughput is calculated iteratively until the performance of the system
converges. Because the resources used by one user in one sector may interfere with other
users, the system converges when it is stable in the selection of Modulation and Coding
Schemes (MCS) for communication and assignment of resources. In the outer loop, the first
automatic adjustment of the framework is done, in order to fulfill the service requirements of
the user.
The optimization algorithm tests different configurations for different parameters that have
high reconfiguration costs in a real network evaluation such as site location and number, tilt,
or azimuth. It stops when a cost function based on KPIs meets the needs of the service
provider. With the use of an inner and outer optimization loop, the optimization procedure

30
becomes an integrated two-step method, in which every tested configuration presents an
optimal frequency planning. Efficient capacity calculations that allow intensive system level
simulations are introduced. After the resource allocation is performed, CINR (and throughput)
are calculated for each user whose best server (Si), is interfered in DL by other stations (Sj);
only if Si and Sj are using the same resource for transmission within a distance smaller than
the system reuse distance. The final interference suffered by the user will be the sum of all the
interference rays coming from neighboring base stations (Sj) [26].
Different configurations are searched by a simulated soft algorithm in both the inner and
outer optimization loop. The outer loop gets optimal values for antenna tilt and azimuth, and
Reference Signal (RS) position from a given set of candidate sites, with the optimal
assignment of channels calculated in the inner loop [3]. In order to optimize and improve
system performance, many parameters must be tuned. The section presents some optimization
procedures.
2.7.2.2 Network Consistency Analysis
The cellular network is a complex system, made up of a very large number of components
and elements. Base station deployment might be erroneous and so is the record of the
deployment details within the database describing the network. Wrong cell location, wrong
sector azimuth, weak coverage, weak signal level, Call Setup Failures, Paging Failures, Call
Drops, blocking, and cross feeders (connection of one sector radio equipment to the antenna
of another sector by mistake) are typical examples of such problems. The measurements as
acquired during real and virtual drive tests are an excellent source of information for such
errors. Consider a drive test taken in urban area at Taiz city.
Continuous wave (CW) testing, also called CW drive testing, is essential to the RF
planning process and deployment of cellular networks. A CW test should be conducted to
examine the signal levels in the area of interest: indoor, outdoor, and in vehicle. There are two
types of drive tests:
 CW Drive: A CW drive test is conducted through different routes in the area to be
covered before the network is deployed. A transmit antenna is placed in the location of
interest (future site), and is configured to transmit an un-modulated carrier at the
frequency channel of choice. A vehicle with receiver equipment is used to collect and
log the received signal levels.

31
Figure 2.12: Optimization framework.

32
 Optimization Drive: This drive test is conducted after the cellular network is in
operation (different call durations, data uploads, and data downloads). Thus, the
modulated data signal is transmitted and then collected by the on-vehicle receiver
equipment. The data are then analyzed for different performance parameters such as
reference channels, power measurements and block error rates [26].
2.7.2.3 Optimization by Monte Carlo Algorithm
Monte Carlo simulation is often used in cellular network planning and optimization due to
the high computational load that dynamic simulation would require in an iterative process that
may need thousands of simulations. This kind of simulation is snapshot based and represents
an instant of the network performance with fixed position of MSs. The simulator takes
multiple Monte Carlo snapshots to statistically observe the network behavior.
Monte Carlo simulations are static rather than dynamic. The population of UEs is
redistributed across the simulation area for every simulation snapshot. For each snapshot, the
uplink and downlink transmit power requirements are computed based upon link loss, and the
level of interference. By considering a large number of instants in the time, the simulation is
able to provide an indication of the probability of certain events occurring (for example, the
probability that a UE will be able to establish a connection at a specific location). The
simulation is also able to provide an indication of average performance such as cell
throughput and downlink transmit power. An optimization algorithm iteratively checks the
estimated interference and goes through different possible solutions for channel assignments
before the Radio Resource Management (RRM) process.
Atoll uses Monte Carlo simulations to generate realistic network scenarios (snapshots)
using a Monte Carlo statistical engine for scheduling and resource allocation. Realistic user
distributions can be generated using different types of traffic maps or subscriber data. Atoll
uses these realistic user distributions as input for the simulations.

33
Monte Carlo simulation, or probability simulation, is a technique used to understand the
impact of risk and uncertainty in financial, project management, cost, and other forecasting
models. When you have a range of values as a result, you are beginning to understand the risk
and uncertainty in the model. The key feature of a Monte Carlo simulation is that it can tell
you based on how you create the ranges of estimates likely the resulting outcomes are [19].
The calculations performed during a Monte Carlo simulation include determining the
serving cells for each mobile; performing fractional power control and power adjustment,
calculating the uplink allocated bandwidth, calculating channel throughputs at mobile
locations, scheduling and resource allocation to mobiles, and calculating the user throughputs
depending on the resources allocated to them. Once the project configuration is completed,
traffic density map is imported and configured into the project and path loss is generated;
Monte Carlo simulations can then be run. All the designs in Atoll are just evaluated based on
Monte Carlo simulations and the pre-defined prediction studies [22].
2.7.2.4 Optimization by Neighbor Re-planning
One of the most sensitive processes that take place in a cellular network is the handover
process, by which a mobile switches its serving cell (or cells). The starting point of the
handover process is the neighbor list transmitted by a cell, indicating to all the terminals it
serves which cells can be candidates to handover to. List optimization means trimming out
cells to which the probability of successful handover is low and populating it with cells with
which the serving cell has a large overlapping coverage area. Thus, mobiles and network
resources are not wasted in futile scans and fruitless handover attempts.
The optimization process is based on assessment of the overlap between two cells. This
overlap can be studied both by predictions and by measurements and reports of the mobile
terminals. Proper weighting should be given to predictions versus measurements, and also to
the different types of traffic encountered [26].
2.7.2.5 Optimization by Automatic Frequency Planning
The frequency channels and permutation codes are instruments by which interference from
one cell can be isolated from the other. In LTE, fractional frequency reuse has been adapted,

34
in which the channels are partitioned into non-interfering segments that have to be allocated
as well. In LTE this is done by using different permutations of the OFDMA subcarriers. The
permutation base that governs those permutations must be controlled as well.
Optimization of those parameters is based on the concept of the impact or interference
matrix. An entry in this matrix describes the impact of interference of one cell on the other.
The impact can be described in terms of the area loss or traffic loss at the victim cell as a
function of the frequency channel. The loss can be assessed using measurements results,
predictions a combination of the measurements and predictions. Once a combination is used,
geographical positioning of the measurements is necessary. The planning algorithm then
works to find a frequency and code plan that would reduce the total impact of interference to
minimum [26].
2.7.2.6 Cell Reconfiguration
We mean the set of parameters referring to the antennas and radio deployment. Those
include the number of sectors, antenna types, antenna direction in azimuth and tilt and
antenna heights, as well as the cell transmission power. Tuning each of those parameters is a
trade-off between the coverage of a serving cell and the interference to other cells. Tilting an
antenna down, for instance, reduces the interference to far-away cells but reduces the
coverage in the high floors of a nearby building [26].
For this optimization, positioning the measurements is essential even if the optimization is
based on measurements alone. The effect of a configuration change, such as tilting the
antenna, may depend very strongly on the location of the terminal [3].
2.8 Comparison of Our Study and Else Study
We compare between our study (LTE network optimization for urban area at Taiz city) and
last study (LTE network planning and optimization) [27] which have been approximately
implemented on the same area; as shown in the Table 2.10. Table 2.10 show almost
parameters of the proposed LTE network is enhanced.

35
Table 2.10 : Comparison of our study and last study
Comparative Last Study [27] Our Study
The Ratio Number of Rejected Users 34.50% 8.30%
The Ratio Number of Connected Users 65.50% 91.70%
Peak RLC Cumulated DL Throughput 203.61 Mbps 1,039.73
Mbps
Peak RLC Cumulated UL Throughput 42.11 Mbps 383.61 Mbps
Mobile Internet Access DL Throughput 110.04 Mbps 266.35 Mbps
Mobile Internet Access UL Throughput 19.99 Mbps 59.85 Mbps
Video Conferencing DL Throughput 576 Kbps 59.9 Mbps
Video Conferencing UL Throughput 320 Kbps 57.22 Mbps
VOIP DL Throughput 6.84 Mbps 6.99 Mbps
VOIP UL Throughput 6.31 Mbps 6.91 Mbps
Minimum Connection Success Rate Per Site )%( 69.96 85.36
Maximum Connection Success Rate Per Site )%( 100 99.27
LTE Coverage )%( 57.9 98.04
Maximum CINR (%) 34.03 77.06
2.9 Summary
This chapter presented the basic technologies which form EPS in LTE. The EPS provides
only packet switched, and IP-based connectivity service. Relating to this approach, the
protocols used between the elements have been changed towards the more common Internet
protocols. The network architecture has also been flattened by moving intelligence towards
the base station, which decreases the latency over the network.
The radio interface uses more efficient and spectrally extensible transmission schemes
OFDMA and SC-FDMA. Additionally, the multiple antenna technology MIMO and ICIC
have been introduced to increase data rates in good radio conditions.
The planning of coverage and capacity are used for calculate the number of site in
network. These basic building blocks are important to understand, since they provide the

36
foundation for higher level functions. Such functions include planning of urban area, which is
the main topic of this thesis. The Planning and optimization are discussed in the next chapter.

37
CHAPTER 3
METHODOLOGY
3.1 Introduction
In this chapter, a fixed LTE planning in urban area of Taiz city is provided and the
performance for the basic minimal configuration based on the LTE system profiles is also
supplied. A network dimensioning for the residential market is performed.
The aim of this project is estimation of the approximate number of base stations needed to
fulfill the requirement on the coverage, the capacity and the quality of service. The
assumptions are considered in the geographic features and the different population in urban
area of Taiz city. This chapter also serves as an important basis for the later economic
analysis.
The radio network planning and optimization process can be divided into different phases.
In the preplanning phase, the basic general properties of the future network are investigated,
for example, what kind of mobile services will be offered by the network, what kind of
requirements the different services impose on the network, the basic network configuration
parameters and so on.
The second phase is the planning. A site survey is done about the to-be-covered area, and
the possible sites to set up the base stations are investigated. All the data related to the
geographical properties and the estimated traffic volumes at different points of the area will
be incorporated into a digital map, which consists of different pixels, each of which records
all the information about this point. Based on the propagation model, the link budget is
calculated, which will help to define the cell range and coverage threshold. There are some
important parameters which greatly influence the link budget, for example, the sensitivity and
antenna gain of the mobile equipment and the base station, the cable loss and the fade margin.
Based on the digital map and the link budget, computer simulations will evaluate the different
possibilities to build up the radio network part by using some optimization algorithms. The
goal is to achieve as much coverage as possible with the optimal capacity, while reducing the
costs also as much as possible. The coverage and the capacity planning are of essential
importance in the whole radio network planning. The coverage planning determines the

38
service range, and the capacity planning determines the number of to-be-used base stations
and their respective capacities.
In the third phase, constant adjustment will be made to improve the network planning.
Through driving tests, the simulated results will be examined and refined until the best
compromise between all of the facts is achieved. Then the final radio plan is ready to be
deployed in the area to be covered and served.
A network can be either coverage or capacity limited, so the dimensioning is carried out
both from a coverage perspective and a capacity perspective, respectively. LTE Radio access
network planning refers to analytical approach which is based on algorithmic formulation and
focuses on the radio engineering aspect of the planning process, i.e., on determining the
locations, estimated capacity and size of the cell sites (coverage and capacity planning), and
assigning frequencies to them by examining the radio-wave propagation environment and
interferences among the cells [18].
3.2 Network Planning
The LTE radio network planning simulation is intended to carry out the link budget
calculation, propagation modeling using the terrain model, coverage estimation and capacity
evaluation.
In this project, simulation is used to investigate the Radio Access Network (RAN) nominal
planning of LTE networks as it is done using Atoll simulation environment. In our cases, the
radio link budget calculation was simply done by using Excel Microsoft Program or its
simplicity and its good results. According to the steps followed as shown in Figure 3.1.
These steps involved in planning an LTE network are described below.
1. Open an existing radio-planning document or create a new project.
2. Configure the network by adding network elements and changing parameters, like Site,
transmitter and cell.
3. Carry out basic coverage predictions. In this project, we create coverage predictions to
analyze the following and other parameters for LTE channels in downlink and in uplink:
 Signal levels.
 The Carrier-to-Interference-and-Noise Ratio (CINR).
 Service areas and radio bearer coverage.

39
 Cell capacity and aggregate throughput per cell.
4. Allocate neighbours, Atoll supports the following neighbour types in an LTE network:
- Intra-technology neighbours: which are cells defined as neighbours that also
use LTE. It is chosen it for this project.
Signal-level coverage analysis
(best server, signal-level)
Automatic or manual neighbor allocation
Automatic or manual frequency planning
Automatic or manual physical cell ID
User defined valueMonte-Carlo simulation
Traffic maps
Subscriber lists
Cell load condition
Signal quality and throughput coverage
prediction
Frequency planning
analysis
Coverage prediction
reports
Network configuration
. Configure network parameter
. Add network element
Create new project
Figure 3.1: Planning an LTE network – workflow.

40
Table 3.1: Planning parameters for downlink and uplink of the proposed LTE network
Parameter DL UL
Frequency 2100 MHZ
Bandwidth 20 MHZ
Duplex FDD
Propagation Model Cost-Hata
MIMO Configuration 2x2 MIMO 1x2 MIMO
Tx Power 43 dB 23 dBm
Tx Antenna Gain 18 dBi 0 dB
Body loss 0 dB 0 dB
Feeder Loss 0.4 0.4 dB
Noise Figure 7 dB 2.2
Throughput 1024 kbps 384 kbps
eNB Antenna Height (m) 30
UE Height (m) 1.5
Penetration Loss (dB) 17
Planning Area (km2
) 21.97
Cell Area (km2
) 0.288
Site Area (km2
) 0.864
Inter Site Distance (km) 0.999
#Site 34
- Inter-technology neighbours: which are cells defined as neighbours that use a
technology other than LTE.
5. Allocate frequencies, 2100 MHz is selected.
6. Allocate physical cell IDs.
7. Before making more advanced coverage predictions, Cell load conditions must be defined.
The cell load conditions can be defined in the following ways:
- Realistic cell load conditions can be generated by creating a simulation based
on traffic maps and subscriber lists (Monte Carlo Simulation).
- Cell load conditions can be defined manually either on the Cells (User Defined
Value).
8. Make LTE specific signal quality coverage predictions using the defined cell load
conditions.

41
9. If necessary, modify network parameters to study the network with a different frequency
plan (Frequency Plan Analysis). After modifying the network’s frequency plan, you must
perform steps (Monte Carlo Simulation and User Defined Value) again [19].
3.3 Coverage and Capacity Planning
In this project, the urban areas of Taiz city are chosen. The chosen area is about 21.97 km2
with a population of 510,486 which is distributed into this region with assume the same
densities. After collecting all information about the area of planning which was mainly given
by Taiz Information Center [20], we start to calculate planning parameters using Excel based
tool which is designed by Nokia Simense Network (NSN). Dimensioning tool comprises of
two main parts presented as ‘Link Budget’ and 'Site Count' sheets.
The design parameters listed in the Table 3.1 are the inputs to the NSN Excel based tool and
was chosen carefully according to the type of terrain and city type (urban terrain).
From the coverage planning calculation, we get that sites number as 26 sites. On the other
hand, we got from capacity planning 34 sites. So we chose the largest number as it will
satisfy the requirements of both type of planning. So the sites will be distributed among
regions as determined before and the location of each was set using Hexagonal tool that exist
in Atoll for urban area and considering inter-site distance ( the distance between two site) and
the names of sites. According the output of the tool the expected throughput for DL urban
area is 52 Mbps/site, while the expected throughput for UL urban area is 12 Mbps/site.
From the capacity planning calculation, we chose area of 21.970 km2
with 76,571
subscribers that are chosen according to the population approximately 510,486 in these area
and we assume that 15% subscribers from the total population.
The traffic in urban area is more than others region, because that user behavior in using the
services is different (VoIP, Video conferencing, Web browsing, FTP, High Speed Internet,
Real time gaming, Mobile Internet Access); thus user type is high (no medium or low) also,
corporations, Banks, Hospitals, Offices and vehicle traffic are found. Thus, the high data rates
have been provided here.

42
3.4 ATOLL Modeling
We used the software tool Atoll radio planning and simulation, which has been developed
by the company Forks. With the help of this tool, the design parameters of the network and
relevant simulations will be performed to verify that the objectives. Atoll can predict radio
coverage, manage mobile and fixed subscriber's data, and evaluate network capacity. Atoll
uses Monte Carlo simulations to generate realistic network scenarios (snapshots) using a
Monte Carlo statistical engine for scheduling and resource allocation. Realistic user
distributions can be generated using different types of traffic maps or subscriber data. Atoll
uses these realistic user distributions as input for the simulations [21].
3.4.1 Area of Planning
In this project, we chose the urban area Taiz city. We Define the geographic area to be
covered (in Google earth and atoll), which is estimated at 21.970 km2
with a population of
510,486 which is distributed into Urban region as illustrated in the following Figure 3.2.
3.4.2 Designing of LTE Network
3.4.2.1 Modeled LTE Maps
The LTE project is created by importing the maps for the urban area of Taiz city. There
are many index files of different folders that are grouped charts: Heights (map type altitudes)
Clutter (clutter type classes), Ortho (image) and Vectors (linear). The resolution of the maps
that we used is 50 m, which in principle is sufficient because the target area topography is
fairly uniform and regular.
3.4.2.2 The Digital Terrain Model (DTM)
The Digital Terrain Model (DTM) is a map of heights and contains altimetry and
topographic relief of the work area. The data contained in this map use to compute the
diffraction attenuation of the terrain. The altimetry map used in this study is shown in Figure
3.3.

43
3.4.2.3 Orthogonal Map
Ortho map is simply an aerial photo of the city. It does not use in the calculations, but it
useful for printouts background and visual localization. Figure 3.4 shows the Ortho image of
Taiz city.
Figure 3.2: Map of the study region.
Figure 3.3: Digital map of Taiz urban.

44
Figure 3.4: Ortho map of Taiz urban.
3.4.2.4 Clutter Class and Vectors Map
The clutter map describes the nature of the environment on each point of the area: streets,
vegetation, water, building and free classes that are not predefined but can be set for
particular calculations. The clutter map of the proposed area is shown in Figure 3.5. As
shown in the legend, there are 17 types of zones.
The sites are added to the area, the transmitters previously are calculated and the longitude
and latitude of each site are entered to Atoll. To locate the sites, we start from the center of an
area and then move by 0.999 km in all directions.
Figure 3.5: Clutter class and vectors map of Taiz urban.

LTE NETWORK OPTIMIZATION FOR URBAN AREA AT TAIZ CITY

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