Lte Planning and Specific Propagation Model Selection (1)

8/18/2019 Lte Planning and Specific Propagation Model Selection (1)

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LTE Planning and Specific Propagation

Model Selection

Prepared by: Khawla Daraghmeh

Ola Mashaqi

Suhad Malayshi

Submitted inPartial Fulfillment requirements of BSc of Degree in

Telecommunication Engineering

Supervisor: Dr. YousefDamaAn-Najah National University

2015


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AbstractLTE Planning and Specific Propagation Model Selection

Key words: LTE, Propagation Model, Link budget, Capacity, Coverage, Path Loss,

Received Power

The whole world tends to use the high rates multimedia applications. High-speed data over

cellular networks will enable a rich suite of multimedia services. LTE is the latest mobile

generation that achieves the required data demand. The number of LTE subscribers worldwide is

rising rapidly and we will catch it in the near future.

The project aims to design LTE network and to specify very accurate and efficient propagation

model. In our case, the area under test is Nablus city. Our project includes numerous steps. At

the beginning, Mobile Planning Process was discussed. Then, we calculate link budget using

Jawwal Company dimensioning tool and specifications that leads us to start in coverage

planning, after that we use some statics provided by Jawwal Company used to complete the work

on capacity dimensioning .After finding number of LTE sites From Coverage and Capacity

Dimensioning, these sites will be simulated by allocating it on a map tool provided by Jawwal

and show received Power level and minimum achievable data rate.

Also in this project, we provide a general theoretical overview of LTE optimization features as

an important phase in any network planning.

An important issue to discuss is site specific propagation model, because all planning procedures

are based on which propagation model is used. In this part of our project we will build a model

similar to Nablus city using Wireless InSite tool considering path loss and received power graphs

for each model. We also make a simulation of propagation path and spread time for Full 3D

propagation model.


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Acknowledgments

First of all, we would like to thank Allah who has given us the power to complete this project.

We would using this opportunity to express our gratitude to everyone who supported us

throughout the project, gratefully and sincerely thank Dr. YousefDamaa for his guidance,

understanding, patience, and most importantly during our graduation project.

A special thanks to Eng.AntarSalim, Eng. ZaidAlkilani and Jawwal Company for all the timeand help they provided

We would like also to thank our parents for their support .Lastly, we offer our regards and

blessing to all of those who inspired us during the completion of this project


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Disclaimer Statement

This report was written by students at the Telecommunication Engineering Department, Faculty

of Engineering, An-Najah National University. It has not been altered or corrected, other than

editorial corrections, as a result of assessment and it may contain language as well as content

errors. The views expressed in it together with any outcomes and recommendations are solely

those of the students. An-Najah National University accepts no responsibility or liability for the

consequences of this report being used for a purpose other than the purpose for which it was

commissioned


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ContentsAbstract ......................................................................................................................................................... 2

Acknowledgments ......................................................................................................................................... 3

Disclaimer Statement .................................................................................................................................... 4

Contents ........................................................................................................................................................ 5

List of Figures ............................................................................................................................................... 8

List of Tables .............................................................................................................................................. 10

List of Abbreviations .................................................................................................................................. 11

1Introduction ............................................................................................................................................... 14

1.1 Amis and objectives .......................................................................................................................... 14

1.2 Motivation ......................................................................................................................................... 15

1.3 Report structure ................................................................................................................................. 15

2 Standards and Constrains ......................................................................................................................... 16

2.1 Standards ........................................................................................................................................... 16

2.2 Constrains ......................................................................................................................................... 17

3 LTE network dimensioning and planning ................................................................................................. 18

3.1 Planning process ............................................................................................................................... 18

3.2 Pre-Planning phase: Dimensioning of LTE Network ....................................................................... 19

3.3 Planning phase .................................................................................................................................. 19

3.4 Optimization phase ........................................................................................................................... 20

4 Coverage and Cell Capacity Planning ..................................................................................................... 21

4.1 Coverage Planning ............................................................................................................................ 21

4.2 Cell Capacity planning ...................................................................................................................... 22

4.3 Dimensioning Tool ........................................................................................................................... 23

4.4 Coverage and Capacity Planning Results ......................................................................................... 24

4.4.1 Coverage Planning Results ........................................................................................................ 244.4.2 Cell Capacity Planning Results .................................................................................................. 25

5 LTE Sites Allocation ................................................................................................................................ 27

5.1 Introduction to LTE Sites Allocating ................................................................................................ 27

5.2 LTE Network Architecture ............................................................................................................... 27

5.3 Site Allocation Procedures ................................................................................................................ 29


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5.2.1 Tool Description ........................................................................................................................ 30

5.3 Simulation Parameters ...................................................................................................................... 30

5.3.1 Antenna parameters.................................................................................................................... 30

5.3.2 Cell power parameters ............................................................................................................... 32

5.4 Site Allocation Results ...................................................................................................................... 33

5.4.1 Rx level ...................................................................................................................................... 33

5.4.2 Maximum achievable data rate for each user ............................................................................. 35

6 LTE KEY SON Features ......................................................................................................................... 39

6.1 Introduction to LTE Optimization .................................................................................................... 39

6.2 SON in 3GPP .................................................................................................................................... 39

6.3 SON Framework ............................................................................................................................... 40

6.3.1 SELF-Configuration................................................................................................................... 40

6.3.2 Self ‐Optimization ....................................................................................................................... 40

6.3.3 SELF-HEALING ............................................................................................................................ 41

6.4 SON Use Cases ................................................................................................................................. 41

6.4.1 Coverage and Capacity Optimization (CCO) ............................................................................ 41

6.4.2 Mobility Robustness Optimization (MRO) ................................................................................ 42

6.4.3 Mobility Load Balancing Optimization (MLB) ......................................................................... 42

6.4.4 Intra-LTE Handover Feature ...................................................................................................... 43

6.4.5 Automated Neighbor Relations (ANR) ...................................................................................... 44

6.4.6 PCI Conflict Reporting .............................................................................................................. 45

6.4.7 16-QAM uplink and 64-QAM Downlink .................................................................................. 47

6.4.8 Dual Band Support ..................................................................................................................... 47

6.4.9 Support for 15km CPRI Link ..................................................................................................... 47

6.4.10 System Information Modification ............................................................................................ 47

6.4.11 Enhanced Observability ........................................................................................................... 48

7 Site Specific Propagation Model .............................................................................................................. 49

7.1 propagation models ........................................................................................................................... 49

7.1.1 Hata Model (Okumura Hata Model) .......................................................................................... 49

7.1.2 Cost Hata Model ........................................................................................................................ 50

7.1.3 Full 3D Propagation Model ........................................................................................................ 50

7.2 Tool Description ............................................................................................................................... 52


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7.2.1 Features ...................................................................................................................................... 53

7.2.2 Study areas ................................................................................................................................. 53

7.2.3 Transmitters ............................................................................................................................... 53

7.3.4 Receivers .................................................................................................................................... 53

7.3.5 Materials .................................................................................................................................... 53

7.3.6 Antennas .................................................................................................................................... 54

7.3.7 Waveforms ................................................................................................................................. 54

7.3.8 Requested Output ....................................................................................................................... 54

7.3.9 Output ........................................................................................................................................ 54

7.3 Design Description ............................................................................................................................ 54

7.3.1 Features and Environment Layout ............................................................................................. 55

7.3.2 Materials .................................................................................................................................... 55

7.3.3 Waveforms ................................................................................................................................. 55

7.3.4 Antennas .................................................................................................................................... 56

7.3.5 Transmitters and Receivers ........................................................................................................ 57

7.3.6 Study Areas ................................................................................................................................ 58

7.4 site specific propagation model results ............................................................................................. 58

7.4.1Comparison to Path Loss Measurements for Each Propagation Model ...................................... 58

7.4.2 Comparison between Received Powers of Propagation Models ................................................ 72

7.4.3 Full 3D propagation path and delay spread................................................................................ 80

7.4.4 Effects of number of reflections and retransmissions on path loss ............................................ 82

8 Effects of the Project on Health society and Economy ............................................................................ 85

8.1 LTE and economy ............................................................................................................................. 85

8.2 LTE and society ................................................................................................................................ 85

8.3 LTE and Health ................................................................................................................................. 85

9 Conclusion and Limitations ..................................................................................................................... 87

9.1 Conclusion ........................................................................................................................................ 87

9.2 Limitation .......................................................................................................................................... 87

References ............................................................................................................................................... 88

Appendices .................................................................................................................................................. 90


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List of FiguresFigure 3-1 mobile planning process ............................................................................................................ 18

Figure 4.1 typical link budget example ....................................................................................................... 21

Figure 4.2 Coverage Planning Proccess....................................................................................................... 22

Figure 4.3 Cell Capacity Planning Process ................................................................................................... 23

Figure 4.4 dimensioning tool logo .............................................................................................................. 23

Figure 5.1: LTE Network Architecture ......................................................................................................... 28

Figure5.2: some of sites distribution over a google earth .......................................................................... 29

Figure5.3: Mentum Planet Tool Logo ......................................................................................................... 30

Figure5.5: Antenna simulation Parameters ................................................................................................ 32

Figure5.6: Cell Power Parameter ................................................................................................................ 33

Figure5.8 RSSI color levels .......................................................................................................................... 34

Figure 6.1 Mobile Planning Process ............................................................................................................ 39

Figure 6.2 Coverage gap optimization ........................................................................................................ 41Figure 6.3: interfaces involved in intra LTE Handover ................................................................................ 43

Figure 6.4: the process to detect and add intra-frequency LTE Handover ................................................. 45

Figure 1-5 Physical Cell ID Deployment ...................................................................................................... 46

Figure 7.1 Wireless InSite elements ............................................................................................................ 52

Figure 7.2: Environment Layout .................................................................................................................. 55

Figure7.3: Material Feature ........................................................................................................................ 55

Figure 7.4 waveform properties ................................................................................................................. 56

Figure 7.5 Antenna Specifications and Pattern........................................................................................... 57

Figure 7.6 Transmitter Configuration ......................................................................................................... 57

Figure 7.7 Transmitter and Recovers Location ........................................................................................... 58Figure 7.8 Study areas ................................................................................................................................. 58

Figure7.9: Hata Path Loss along route 1 and 2 using Wireless InSite Tool ................................................. 59

Figure7.10: Path Loss Color Levels For Hata model .................................................................................... 59

Figure7.11: Hata Model area Coverage Prediction ..................................................................................... 60

Figure7.12: Hata Path Loss along each rout vs distance using matlab ....................................................... 61

Figure7.13: Rx grid around rout 1 ............................................................................................................... 62

Figure7.15: Cost Hata Path Loss along rout 1 and 2 using Wireles InSite Tool .......................................... 63

Figure7.16: Path Loss Color Levels For Cost Hata model ............................................................................ 63

Figure7.17: Cost Hata Model area Coverage Prediction ............................................................................. 64

Figure7.18: Cost Hata Path Loss along each rout vs distance using matlab ............................................... 65Figuree7.19: each Rx grid path loss around rout 1 using Matlab (Cost Hata ) ........................................... 66

Figure 7.20: Full 3D Path Loss along rout 1 and 2 using Wireles InSite Tool .............................................. 67

Figure 7.21: Path Loss Color Levels For Full 3D model ............................................................................... 67

Figure 7.22: Full 3D Model area Coverage Prediction ................................................................................ 68

Figure 7.23: Full 3DPath Loss along each rout vs distance using matlab ................................................... 69

Figure7.24: each Rx grid path loss around rout 1 using Matlab (Full 3D) ................................................... 70


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Figure7.25: Hata Path Loss along rout 1 for all models vs distance .......................................................... 71

Figure7.26: Hata Path Loss along rout 2 for all models vs distance .......................................................... 71

Figure 7.27Hata received Power along rout 1 and 2 using wireless InSite tool ......................................... 72

Figure7.29: received Power prediction calculated by Hata Model ............................................................ 73

Figure7.31: Cost Hata received Power along route 1 and 2 using wireless InSite tool .............................. 75

Figure7.32: received Power Color Levels for Cost Hata model .................................................................. 75

Figure7.33: received Power prediction calculated by Cost Hata Model .................................................... 76

Figure7.34: Cost Hata along received Power vs distance for each rout using matlab .............................. 76

Figure7.35: Full 3D received Power along rout 1 and 2 using wireless InSite tool ..................................... 77

Figure7.36: received Power Color Levels For Full 3D model ..................................................................... 77

Figure 7.37: received Power prediction calculated by Hata Model ........................................................... 78

Figure 7-38Full 3D received Power vs distance for each rout using matlab ............................................... 78

Figure 7.39 received power along rout one for all models using matlab ................................................... 79

Figure7.41: Full 3D Propagation Path (rout 1) ........................................................................................... 81

Figure7.42: Full 3D propagation path pn a Rx Point ................................................................................... 81

Figure7.43: Full 3D delay spread ................................................................................................................. 82

Figure7.44: Full 3D Path Loss with different number of reflection ............................................................ 83

Figure7.45: Full 3D Path Loss with different number of retransmissions .................................................. 84


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List of Tables

Table 1.4 Maximum allowable Path Loss without considering clutter ....................................................... 24

Table 4.2 maximum allowable path loss considering clutter ..................................................................... 24

Table 4.3 cell range ..................................................................................................................................... 24

Table 4.4 site count ..................................................................................................................................... 25

Table 4.5 coverage parameters .................................................................................................................. 25

Table 4.6 DL Site Capacity (Mbps)............................................................................................................... 25

Table 4.7 UL Site Capacity ........................................................................................................................... 26

Table 1.8 number of capacity sites ............................................................................................................. 26

Table 5.1 RSSI ranges and percentages ...................................................................................................... 35

Table 5.2 DL Data rate Percentages ............................................................................................................ 37


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List of Abbreviations

Abbreviation Stands for

LTE Long Term Evaluation

2G The second generation

3G The third generation

4G The fourth generation

3GPP The third generation partnership generation

RF Radio Frequency

GSM Global System for Mobile

CDMA Code Division Multiple Access

WCDMA Wideband Code Division Multiple Access

SON Self Organization Network

UMTS Universal Mobile Telecommunication System

E-UTRA Evolved Universal Terrestrial Radio Access

UTRAN Evolved Universal Mobile Telecommunications System Terrestrial RadioAccess Network

UE User Equipment

MIMO Multiple Input Multiple Output

CoMP Coordinated Multiple Point

BSs Base Stations

dBm Decibel-mill watts

dBi Decibel isotropic

dB Decibel

QPSK Quadrature Phase Shift Keying

MAPL Maximum Allowable Path Loss


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DL Downlink

UL Uplink

eNB Evolved Node B

MME Mobility Management Entity

RRM Radio Resource Management

NAS Non-Access Stratum

CN Core Network

PDN Packet Data Network

S-GW Serving Gateway

QoS Quality of Service

P-GW Packet Data Network PDN Gateway

IP address Internet Protocol address

EPC Evolved Packet Core

PDCCH Physical Downlink Control Channel

EIRP Effective Isotropic Received Power

PDSCH Physical Downlink Shared Channel

SS Synchronization Signal

RSSI Received Signal Strength Indicator

ITU International Telecommunication Union

OPEX Operational Expenditure

ANR Automatic neighbour relations

PCI Physical Cell Identity

CGID Cell global ID

CAPEX Capital Expenditure

MDT Minimization of Drive Tests


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CCO Coverage and Capacity Optimization

MRO Mobility Robustness Optimization

RLF Radio Link Failures

MLB Mobility Load Balancing

RATs Radio Access Technologies

RBS Radio Base Stations

NRT Neighbour Relation Table

TAC Tracking Area Code

PLMN available Public Land Mobile Network

NR Networks Relation

HO HandOver

QAM Quadrature Amplitude Modulation

DUL Digital Unit

SFPs Factor Plugins

CPRI Common Public Radio Interface

SBR Shooting and Bouncing Rays

LOS Line Of Sight

Tx/Rx Transmitter/Receiver

VSWR Voltage Signal to Wave Ratio

WHO the world Health organization


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1Introduction

LTE or Long Term Evolution is the next generation of mobile 4G for both Global System

Mobile communication 2G and Code Division Multiple Access 3G cellular carriers. It was

defined by the 3G partnership project in 3GPP Release 10 specification. LTE uses a different air

interface and packet structure than the previous systems.

In this chapter we show the aims and objectives for the project, motivations and overview of the

report structure.

1.1 Amis and objectives

This project aims to design LTE network for Nablus city through planning tools provided by

Palestine Cellular Communications Company (Jawwal) and specify an accurate propagationmodel. The main objectives of project may describe as follows:

1. To provide a general theoretical overview of mobile network planning process.

2. To calculate LTE link Budget using Jawwal Company dimensioning tool and

specifications.

3. To develop LTE coverage and capacity planning.

4. To allocate the sites on Nablus plane using Jawwal MP Tool.

5. To provide a general theoretical overview of LTE SON features.

6. To provide a general theoretical overview of site specific propagation model.7. To build a model similar to Nablus city using Wireless InSite tool.

8. To draw a path loss and received power graphs for each propagation model under

discussion.

9. To simulate propagation path and spread time for Full 3D propagation model

10. To Write The report


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1.2 Motivation

The world eye today is working strongly to deploy LTE networks. Most of the developmentcountries now have LTE. By the year of 2016, LTE subscribers will be around one billion. The

main motivations of working strongly to have LTE are summarized as below:

1. Need to ensure the continuity of competitiveness of the 3G system for the future

2. User demand for higher data rates and quality of service

3. Packet Switch optimized system

4. Continued demand for cost reduction

5. Low complexity

6. Avoid unnecessary fragmentation of technologies for paired and unpaired band operation

1.3 Report structure

This report contains nine chapters , the first chapter introduction to our work, the second chapter

includes standards of LTE , the third and fourth chapter describes LTE planning processes for

Nablus city and coverage , capacity dimensioning, the fifth chapter shows LTE site allocation

on Nablus map was done. Then we discussed in chapter six some of LTE SON feature, then in

chapter seven we compared between propagation models which are Hata, Cost_Hata and full 3D.The next chapter the effect of our project on economy, society and environment. Finally the last

chapter contains the conclusion and limitations.


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2 Standards and ConstrainsLong Term Evolution (LTE) standardization is being carried out in the 3rd Generation

Partnership Project (3GPP), as was also the case for Wideband CDMA (WCDMA), and the later

phase of GSM evolution. This chapter illustrate the standards for which LTE is based and the

constrains of LTE networks.

2.1 Standards

LTE is based on standards developed by the 3rd Generation Partnership Project (3GPP). LTE

may also be referred more formally as Evolved UMTS Terrestrial Radio Access (E-UTRA) and

Evolved UMTS Terrestrial Radio Access Network (E UTRAN). Even though 3GPP created

standards for GSM/UMTS family, the LTE standards are completely new, with exceptions where

it made sense [1].

LTE-Advanced was required to deliver a peak data rate of 1000 Mbps in the downlink, and 500Mbps in the uplink. In practice, the system has been designed so that it can eventually deliver

peak data rates of 3000 and 1500 Mbps respectively, using a total bandwidth of 100MHz that is

made from five separate components of 20MHz each. Note, as before, that these figures are

unachievable in any realistic scenario [1].

The specification also includes targets for the spectrum efficiency in certain test scenarios.

Comparison with the corresponding figures for WCDMA implies a spectral efficiency 4.5 to 7

times greater than that of Release 6 WCDMA on the downlink, and 3.5 to 6 times greater on the

uplink. Finally, LTE-Advanced is designed to be backwards compatible with LTE, in the sense

that an LTE mobile can communicate with a base station that is operating LTE-Advanced and

vice-versa [1].

3GPP has held a number of discussions on LTE-Advanced during 2008, and the technologies to

be investigated include [2]:


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1. Relay nodes. These are targeted for extending coverage by allowing User Equipment

(UE) further away from the base station to send their data via relay nodes that can hear

the eNodeB better than, for example, UE located indoors.

UE dual transmit antenna solutions for uplink Single User MIMO (SU MIMO) and diversity

MIMO.

2. Scalable system bandwidth exceeding 20 MHz, potentially up to 100 MHz. In

connection with this, the study has been investigating aspects related to multiple access

technology with up to 100 MHz system bandwidth, and it is foreseen to be based strongly

on the existing LTE solutions with extensions to larger bandwidths. How to extend the

bandwidth (and how that is reflected in the multiple access) is the first topic where

conclusions are expected in LTE-Advanced studies.

3.

Nomadic/Local Area network and mobility solutions.

4. Flexible Spectrum Usage.

5. Automatic and autonomous network configuration and operation.

6. Coordinated Multiple Point (CoMP) transmission and reception, which is referring to

MIMO transmission coordinated between different transmitters (in different sectors or

even different sites in an extreme case).

2.2 Constrains

Jawwal Company uses bandwidth of 4.8 MHz to support GSM900 which is a very narrow

bandwidth deploys LTE. The installation of LTE network on such bandwidth is not applicable

since there is no license .In current project, 10 MHz bandwidth is used to design the LTE

network which is not licensed yet making LTE network inapplicable in Palestine.


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3LTE network dimensioning and planning In the context of mobile and cellular communication systems, RF Planning is the process of

assigning frequencies, transmitter locations and parameters of a wireless communications system

to provide sufficient coverage and capacity for the services required .This chapter illustrates the

process of planning LTE network.

3.1 Planning process

The flowchart for the network planning process is shown in figure 3.1. After detailed planning

the network is ready for commercial launch, but the post-planning phase continues the process

and targets the most optimal network configuration. Actually the network planning process is a

never ending cycle due to changes in the design parameters [3].

Figure 0-1 mobile planning process

The four main steps in the network planning process are: pre-planning, planning, detailed

planning and optimization. The input for the preplanning phase is the network planning criteria.

The main activity is dimensioning, which gives the initial network configuration as a result. The

first step in the planning phase is nominal planning; it provides the first site locations in the map

based on input from the dimensioning phase. The process continues with more detailed coverage


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planning after site hunting and transmission planning. Detailed Capacity planning is also

included in the planning phase. Detailed planning covers frequency, neighbor and parameter

planning. After detailed planning the network is ready for verification and acceptance, which

finishes the prelaunch activities. After the launch the activities continue with optimization [3].

3.2 Pre-Planning phase: Dimensioning of LTE Network

Dimensioning is the initial phase of network planning. It provides the first estimate of the

network element count as well as the capacity of those elements. The purpose of dimensioning is

to estimate the required number of radio base stations needed to support a specified traffic load

in an area [4].

Dimensioning exercise gives an estimate which is then used for detailed planning of the network.

Once the network is completely planned, network parameters are optimized maximizing the

efficiency of the system.

In the following are listed basic inputs for dimensioning [3]:

1. coverage requirements, the signal level for outdoor, in-car and indoor with the coverage

probabilities;

2. quality requirements, drop call rate, call blocking;

3. frequency spectrum, number of channels, including information about possible needed

guard bands;

4. subscriber information, number of users and growth figures;5. traffic per user, busy hour value;

6. Services.

3.3 Planning phase

The planning phase takes input from the dimensioning, initial network configuration. This is the

basis for nominal planning, which means radio network coverage and capacity planning with a

planning tool [3].

The nominal plan does not commit certain site locations but gives an initial idea about the

locations and also distances between the sites. The nominal plan is a starting point for the site

survey, finding the real site locations. The nominal plan is then supplemented when it has

information about the selected site locations; as the process proceeds coverage planning becomes

completed [3].


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The target for the coverage planning phase is to find optimal locations for BSs to build

continuous coverage according to the planning requirements. Coverage planning is performed

with a planning tool including a digital map and a tuned model for propagation. The propagation

model tuning measurements have been performed with good accuracy [3].

In the capacity planning phase the final coverage plan including composite and dominance

information is combined with the user density information; in this way the capacity can be

allocated. Boundary conditions for capacity allocation are agreed with the customer earlier, i.e.

the maximum RX number per base station. The known capacity hot spots are treated with extra

care and special methods can be used to fulfill the estimated need [3].

3.4 Optimization phase

After the network has been launched the planning and optimization related activities do not end

because network optimization is a continuous process. For the optimization the needed input is

all available information about the network and its status. The network statistic figures, alarms

and traffic itself are monitored carefully. Customer complaints are also a source of input to the

network optimization team. The optimization process includes both network level measurements

and also field test measurements in order to analyses problem locations and also to indicate

potential problems [3].


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4 Coverage and Cell Capacity Planning This chapter gives brief view of how coverage and capacity planning done.

4.1 Coverage Planning

Coverage planning depends on link budget calculation. 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 cell range to be estimated with a suitable

propagation model, such as Hata [5] figure 4.1 shows a typical example of a radio link budget.

Figure 0.1 typical link budget example

Figure 4.2 is flowchart shows the process we follow in coverage planning:


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Figure 4.2 Coverage Planning Proccess

We worked in coverage planning in two considerations: clutter and without clutter.

Without the consideration clutter we found maximum allowable path loss and mapped into cell

count. For 43 dBmeNodeB transmitted power and 18dBi antenna gain and 23 dBm UE

transmitted power assumed to have an isotropic antenna gain.

4.2 Cell Capacity planning

To find the number of sites due to capacity which depends on population density and mobile phone penetration and operator market share. The following chart shows the process of cell

capacity planning

Figure 4.3 shows cell capacity planning flowchart


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Figure 4.3 Cell Capacity Planning Process

4.3 Dimensioning Tool

We worked in coverage and capacity planning using dimensioning tool provided by Jawwal

Company. The tool is” RNT_LTE_Dim v2.3.6 Approved for RL10 / RL20 / RL30 / RL15TD /

RL25TD”. the figure shows tool logo 4.4

Figure 4.4 dimensioning tool logo


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4.4 Coverage and Capacity Planning Results

These Results obtained using dimensioning tool described previously

4.4.1 Coverage Planning Results

The maximum allowable path loss is shown in table 4.1

UL DL

Maximum Allowable Path Loss (dB) (clutter not

considered)

149.7 156.66

Table 4.1 Maximum allowable Path Loss without considering clutter

The consideration of clutter depends on the use of propagation model. Jawwal company use

Macro COST231 (Okumura-Hata) for QPSK modulation and 2 transmitter, 2 receiver MIMO

configuration the maximum allowable path loss is shown in table 4.2

Mapping the MAPL into cell range depending in propagation model using dimensioning tool

leads to cell rang and number of sites

So cell range shown in table 4.3 and site count in table 4.4

Dense urban urban Sub-urban Rural

Cell Range (km) 0.185 0.367 0.992 4.927

Table 4.3 cell range

Dense

urban

urbanSub-

urban

Rural

Maximum Allowable Path Loss (dB)121.27 129.33 132.1 136.92

(clutter considered)

Table 4.2 maximum allowable path loss considering clutter


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Dense urban Urban Sub-urban Rural

Site Count 9 78 4

Table 4.4 site count

Other parameters determined by dimensioning Tool that used in site allocation shown in table

4.5

Dense urban Urban Sub-urban Rural

Cell Area (km2) 0.022 0.088 0.640 15.780

Site Area (km2) 0.066 0.263 1.920 47.341

Inter Site Distance (km) 0.277 0.551 1.489 7.391

Deployment area (km2) 0.550 20.470 6.900 0.019

Site Count 9 78 4 1

Table 4.5 coverage parameters

According to these results, the sites will be allocated and optimized

4.4.2 Cell Capacity Planning Results

According to Jawwal, we assumed that the population number (GSM subscriber) of Nablus city

in 2014 around 163000. Also, we assumed that the Penetration Rate is 30 % of population

number. The Avg. Data Volume per Subscriber per BH is 5.000 MB according to these

assumptions site capacity is calculated in DL Table 4.6 and UL table 4.7.

DL Site Capacity (Mbps)

Dense Urban 59.824

Urban 56.288Suburban 39.835

Rural 30.194

Table 4.6 DL Site Capacity (Mbps)


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Depending on assumed number of subscribers the number of sites due to capacity in uplink and

downlink shown in table 4.8:

#Sites (Capacity DL)

Dense Urban 5

Urban 3

Suburban 3

Rural 1

Table4.8: number of capacity sites

UL Site Capacity (Mbps)

Dense Urban 29.282

Urban 26.985

Suburban 16.441

Rural 8.732

Table 0.7 UL Site Capacity


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5 LTE Sites AllocationThis chapter illustrates the work on site allocation. First, an introduction to site allocation work,

then a brief view of LTE network architecture, the third section demonstrate procedure we

follow to continue the work, section four describes simulation parameters related to antenna and

cell power parameters, finally the results we obtained.

5.1 Introduction to LTE Sites Allocating

After we finished coverage and capacity planning, we obtained the number of sites that have to

be allocated for Nablus city. The site allocations plan will identify sites to ensure that coverage

and data rate is available in appropriate locations.

Site allocation gives an indication of how the network behavior will be after deployment, so it is

an important step in LTE network planning.

5.2 LTE Network Architecture

The LTE network architecture is illustrated in figure 5.1. The data are exchanged between the

UE and the base station (eNB) through the air interface. The eNB is part of the E-UTRAN where

all the functions and network services are conducted. Whether it is voice packets or data packets,

the eNB will process the data and route it accordingly [6].


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Figure 0.1: LTE Network Architecture

The main components of such a network are [5]:

User Equipment (UE): This is the user device that is connected to the LTE network via

the RF channel through the BS that is part of the eNB subsystem.

Evolved NodeB (eNB): The eNB functionalities include radio resource management

(RRM) for both uplink (UL) and downlink (DL), IP header compression and encryptionof user data, routing of user data, selection of MME, paging, measurements, scheduling,

and broadcasting.

Mobility Management Entity (MME): This portion of the network is responsible for

non-access stratum (NAS) signaling and security, tracking UE, handover selection with

other MMEs, authentication, bearer management, core network (CN) node signaling, and

packet data network (PDN) service and selection. The MME is connected to the S-GW

via an S11 interface.

Serving Gateway (S-GW): This gateway handles eNB handovers, packet data routing,

quality of service (QoS), user UL/DL billing, lawful interception, and transport level

packet marking. The S-GW is connected to the PDN (Packet Data Network) gateway via

an S5 interface.


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PDN Gateway (P-GW): This gateway is connected to the outside global network

(Internet). This stage is responsible for IP address allocation, per-user packet filtering,

and service level charging, gating, and rate enforcement.

Evolved Packet Core (EPC): It includes the MME, the S-GW as well as the P-GW.

5.3 Site Allocation Procedures

Our work on site allocation goes through three stages:

1. Allocate sites on Google Earth.

Using Google earth, we allocate 92 sites, each site with three sectors. We take into account a lot

of simulation parameters as clutter (dense urban, urban, suburban, rural), inter site distance, cell

area, total deployment area and antenna specification. Figure 5.2 shows some of sites distribution

for dense areas on Google earth. In appendix 1 attached 92 sites coordinates

Figure5.2: some of sites distribution over a google earth

2. Site coordinates uploaded to Mentum Planet tool.

After sites pointing in Google earth we upload these sites into MP tool that gives the

simulation of Rx level and data rate.


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5.2.1 Tool Description

Site allocation done by a tool provided by Jawwal Company, the tool is Mentum planet planning

tool.

Mentum Planet® is a robust and easy-to-use Windows-based software solution that helps

operators, integrators and equipment vendors plan, manage and improve the performance of

wireless access networks. Mentum Planet supports all major wireless access standards including

LTE-Advanced and Wi-Fi. It addresses all stages of the network lifecycle from strategic

planning to ongoing management of network performance. During the last few years, the

development focus has been on providing operators with outstanding support for the planning of

small cells and heterogeneous networks (HetNets), both in 2D and in 3D. Maximize your

investment, increase revenue, improve profitability and accelerate time-to-market with Mentum

Planet, the world‟s most innovative and advanced wireless access network planning,

management and optimization platform [7]. Figure 5.3 shows tool logo

Figure5.3:Mentum Planet Tool Logo

3. Simulation parameters settings: after site distribution on a MP tool, we set the parameters

for each site. Simulation parameters explained in next section.

5.3 Simulation Parameters

In our work we use many simulation parameters for site allocation

5.3.1 Antenna parameters

The base station is required to have 3 antennas (type 739623,739632,739634) of the following

transmission specifications:

1. Front to back ratio = 28 dB

2. Horizontal eam width 66.5 3. Vertial eam width4.3


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4. Default Azimuth and tilting .antenna tilt0, antenna azimuth 0 , 120 , 240 .

5. Antenna height = 16 m.

The pattern shown in figure 5.4 and antenna simulation parameters 5.5

Figure 5.4 Antennas Pattern


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Figure5.4: Antenna simulation Parameters

5.3.2 Cell power parameters

After mapping sites on Google earth, and for more efficient coverage of power for each site,

power parameters should be set clearly. Power parameters which we are concerned on are: EIRP,

reference signal, Synchronization signal power and average power per PDCCH and per PDSCH.

Figure 5.6 shows cell power parameters.


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Figure5.5: Cell Power Parameter

1. PA power = 43dB.

2. EIRP (dBm) : The EIRP is the effective power transmitted from BS, after variable gains

and attenuations, which can be calculated as the following formula

EIRP = 57.34 dBm

3. Synchronization signal power: The Synchronizing Signal (SS) from LTE base station is a

powerful tool for helping network operators understands the downlink signal quality for

LTE networks.

5.4 Site Allocation Results

The main indicators of network quality are Rx level and cell capacity

5.4.1 Rx level

The power strength (RX Level) for Nablus city after sites allocation is shown figure 5.7 received

signal strength indicator (RSSI).


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Figure 5.7 RSSI (Rx Level)

The most of the region in the city covered by pink color which give us and indicate about the

signal strength is around -55 dB, however there are another colors (Rx levels) at the edges of the

city which are green, yellow and orange sequentially, these colors mean less signal strength than

the pink color, the received signal strength are -56, -75, -85 dB for green, yellow and orange as

shown in figure 5.8.

Figure5.6 RSSI color levels

Table 5.1 shows the area of each range and it's percentage from the total area


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RSSI Ranges Area (km²)Percentage

Sub Area

Percentage

Total Area

-200 ~ -95 0 0 0

-95 ~ -85 0.57409996 1.5381153 0.45506856

-85 ~ -75 1.4869 3.9836679 1.17861271

-75 ~ -65 2.63259983 7.0532002 2.08676815

-65 ~ -55 2.6431 7.081332 2.095091

-55 ~ 0 27.4273 73.48258 21.7406445

Outside range 2.5609 6.861104 2.02993417

Table 0.1: RSSI ranges and percentages

So the percentages of the areas which represent each signal strength level to the total area versus

the signal strength levels are shown in figure 5.9, that the higher percentage of the total area iscovered by the highest signal strength power level

Figure 5.9 RSSI percentage

5.4.2 Maximum achievable data rate for each user

The maximum achievable data rate for each user after sites allocation is shown figure 5.10.

Black has downlink data rate 2.500 MbPs, blue has downlink data rate 5MbPs, green has


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downlink data rate 10 MbPs, yellow has downlink data rate 15 MbPs, orange has downlink data

rate 20MbPs, red has downlink data rate 30 MbPs as shown in figure 5.11.

Figure 5.10- Maximum Achievable Data rate for each user


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Figure 5.11 Data Rates Color levels

Table 5.2 shows the area of each downlink data rate range and it's percentage from the total area.

Figure 5.12 show that most areas have a rate between 5 to 30 MbPs.

Downlink Data

Rate ranges

Area

(km²)

Percentage

Sub Area

Percentage

Total Area

0 ~ 1 0 0 0

1 ~ 5 3.5546 9.523402 2.817605

5 ~ 10 12.4517 33.3603 9.870018

10 ~ 30 16.879 45.22182 13.37938

30 ~ 40 1.8787 5.033369 1.489178

40 ~ 285.8343 0 0 0

Outside range 2.5609 6.861104 2.029934

Table 5.2 DL Data rate Percentages


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Figure 5.12 Downlink rates percentages

0

2

4

6

8

10

12

14

16

Percentage Total Area

Percentage Total Area


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6 LTE KEY SON FeaturesThis chapter illustrated the key SON features of LTE network, the first section is optimization

description the second section reviews in brief SON in 3GPP.Section three discuses LTE SON

framework that includes self-configuration, optimization and healing categories. The fourth

section discusses general basic optimization Features related to mobility and handover.

6.1 Introduction to LTE Optimization

As discussed in chapter one, LTE planning process is consecutive steps as shown in figure 6.1.

Optimization is very important step in LTE network planning which is the last one. The LTE

specification inherently supports SON features.

Figure 0.1 Mobile Planning Process

6.2 SON in 3GPP

3GPP is an alliance and a standards body that works within the scope of the International

Telecommunication Union (ITU) to develop 3rd Generation (3G) and 4th Generation (4G)


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specifications based on evolved Global System for Mobile communications (GSM) standards

[8].

Reduction of cost and complexity is a key driver for Long Term Evolution (LTE), since with its

deployment the new network layer needs to coexist with legacy systems without additional

operating cost. Thus, it is of vital interest for operators to introduce automated engineering

functions that minimize Operational Expenditure (OPEX) and, at the same time, increase

network performance by dynamically adjusting the system configuration to the varying nature of

wireless cellular networks [8].

Deploying and operating cellular networks is a complex task that comprises many activities, such

as planning, dimensioning, deployment, testing, prelaunch optimization, post launch

optimization, comprehensive performance monitoring, failure mitigation, failure correction and

general maintenance. Today, such critical activities are extremely labor intensive and, hence,

costly and prone to errors, which may result in customer dissatisfaction and increased churn [8].

6.3 SON Framework

SON solutions can be divided into three categories: Self-Configuration, Self-Optimization and

Self-Healing.

6.3.1 SELF-Configuration

This is the dynamic plug-and-play configuration of newly deployed eNBs. The eNB will by itself

configure the Physical Cell Identity, transmission frequency and power, leading to faster cell

planning and rollout [9].

The interfaces S1 and X2 are dynamically configured, as well as the IP address and connection

to IP backhaul. To reduce manual work ANR (Automatic neighbour relations) is used. Dynamic

configuration includes the configuration of the Layer 1 identifier, Physical cell identity (PCI) and

Cell global ID (CGID) [9] [10].

Self-configuration mechanism is desirable during the pre-operational phases of network elements

such as network planning and deployment, which will help reduce the CAPEX [11].

6.3.2 Self

Optimization


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Utilization of measurements and performance indicators collected by the User and the base

stations in order to auto-tune the network settings. This process is performed in the operational

state [8] [11].

Self-optimization mechanism is desirable during the operational stage so that network operators

get benefits of the dynamic optimization, e.g., mobility load balancing to make network more

robust against environmental changes as well as the minimization of manual optimization steps

to reduce operational costs

6.3.3 SELF-HEALING

Features for automatic detection and removal of failures and automatic adjustment of parameters

are mainly specified in Release 10. Coverage and Capacity Optimization enables automatic

correction of capacity problems depending on slowly changing environment, like seasonal

variations. Minimization of drive tests (MDT), is enabling normal UEs to provide the same typeof information as those collected in drive test. A great advantage is that UEs can retrieve and

report parameters from indoor environments [8] [9].

6.4 SON Use Cases

This section discuss general basic optimization Features

6.4.1 Coverage and Capacity Optimization (CCO)

This optimization aims at maximizing the system capacity and ensuring there is an appropriate

overlapping area between adjacent cells as shown in figure 6.2. The optimal parameter setting is

acquired by cooperatively adjusting antenna tilt and pilot power among the related cells. This

optimization should operate with some effect even if the measurement reports from UE do not

include their data on their own location [12].

Figure 6.2 Coverage gap optimization


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3GPP specifies the following requirements on CCO [12]:

Coverage and capacity optimization shall be performed with minimal human

intervention.

Operator shall be able to configure the objectives and targets for the coverage and

capacity

Operator shall be able to configure the objectives and targets for the coverage and

capacity

Optimization functions differently for different areas of the network.

The collection of data used as input into the coverage and capacity optimization function

shall be automated to the maximum extent possible and shall require minimum possible

amount of dedicated resources

6.4.2 Mobility Robustness Optimization (MRO)

Mobility Robustness Optimization (MRO) encompasses the automated optimization of

parameters affecting active mode and idle mode handovers to ensure good end-user quality and

performance, while considering possible competing interactions with other SON features such

as, automatic neighbor relation and load balancing. Incorrect handoff parameter settings can

negatively affect user experience and waste network resources due to handoff and radio link

failures (RLF). While handoff failures that do not lead to RLFs are often recoverable and

invisible to the user, RLFs caused by incorrect handoff parameter settings have a combined

impact on user experience and network resources [13].

In addition to MRO, intra-frequency Mobility Load Balancing (MLB) objective is to intelligently

spread user traffi aross the system‟s radio resoures in order to optimize system apaity while

maintaining quality end-user experience and performance. Additionally, MLB can be used to

shape the system load according to operator policy, or to empty lightly loaded cells which can

then be turned off in order to save energy. The automation of this minimizes human intervention

in the network management and optimization tasks [13].

There are multiple approaches towards load balancing for MLB. One of the approaches is

described here and other approaches may exist that supplement this approach [13].

6.4.3 Mobility Load Balancing Optimization (MLB)

Self-optimization of the intra-LTE and inter-RAT mobility parameters to the current load in the

cell and in the adjacent cells can improve the system capacity compared to static/non-optimized


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cell reselection/handover parameters and can minimize human intervention in the network

management and optimization tasks[14].

The load balancing shall not affect the user QoS negatively in addition to what a user wouldexperience sat normal mobility without load-balancing. Service capabilities of RATs must be

taken into account, and solutions should take into account network deployments with overlay of

high-capacity and low-capacity layers where high-capacity layer can have spotty coverage.

Objective: Optimization of cell reselection/handover parameters to cope with the unequal traffic

load and minimize the number of handovers and redirections needed to achieve the load

balancing [14]

6.4.4 Intra-LTE Handover Feature

Intra-LTE Handover is the basic mobility function for UEs in active mode. When one or more

neighbor cells are better than current serving cell the UE is ordered to handover to best cell. Best

cell evaluation is based on measurements of neighbor cells, serving cell and evaluation algorithm

controlling parameters set by eNodeB [15].

Figure 6.3 shows interfaces involved in intra-LTE handovers.

Figure 6.3: interfaces involved in intra LTE Handover

The benefits of the Intra-LTE Handover feature are the following [15]:

• Network apaity is maximized y ensuring that UE are served y the est availale ell.

• Data rates to individual UE within the network are maximized y ensuring that the UE is

served by the best cell.


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• Connected mode mobility within the network is possible with minimal interruptions to data

flows during the handover process

6.4.5 Automated Neighbor Relations (ANR)

Mobile devices can report cells that are not in the neighbor list to the base station they are

currently served by. This information can then be used by the network to automatically establish

neighbor relationships for handovers [16]

The Automated Neighbor Relation (ANR) feature in the RBS removes the need for initial

configuration of neighbor relation lists and greatly simplifies the optimization of them. The

feature will execute autonomously in the RBS and automatically

The process to detect and add a new intra frequency LTE neighbor is outlined below [16]:1. The eNodeB sends each connected UE a list of neighbor PCIs with their cell individual offsets

(Ocn) and configures the conditions that will trigger the events associated to the corresponding

measurements.

2. When the UE detects that the received signal of a given cell becomes stronger than that of the

serving cell by more than a certain offset, the PCI of that cell is reported to the eNodeB, together

with the associated measurement report. UEs carry out this procedure independently of whether

the reported PCIs are part of the NRT.

3. If a reported PCI is not in the NRT, the eNodeB orders the UE to decode the ECGI of the

newly discovered PCI, as well as the Tracking Area Code (TAC) and all available Public Land

Mobile Network (PLMN) IDs. For this to happen, the eNodeB may schedule idle periods to

allow the UE to read the ECGI that is broadcasted by the new neighbor associated with the

detected PCI.

4. After this process has been completed, the UE reports the ECGI of the new neighbor to the

eNodeB.

5. The eNodeB processes this information and may decide to update its NRT. Eventually, it may

setup (if needed) a new X2 connection towards the new neighboring eNodeB. This new NR has

its default attributes configured in such a way that HO, X2 connection setup and ANR actions to

remove this NR are allowed

The process is summarized in figure 6.4


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Figure 6.4: the process to detect and add intra-frequency LTE Handover

6.4.6 PCI Conflict Reporting

Every LTE cell has a PCI that is used during the cell search procedure to distinguish the

transmissions of several cells on the same carrier from each other. Only 504 IDs are available

and neighboring base stations should use a certain combination for easier detection. As it is

sometimes difficult to predict all cell neighbors, auto-configuration functionality is highly

desirable. The mobile is required to report to the network as to which cells it looks out for the

automated configuration process [16].

When a new eNB is established, it needs to select Ph-IDs for all the cells it supports. The Ph_ID

of one cell should satisfy the following two criteria so that no confusion is caused [9].

The Ph_ID of one cell should not be the same as those of his neighbor cells.

The Ph_IDs of the neighbor cells should not be the same.

Figure 6.5 shows an example of Physical Cell ID deployment. In this example, the eNB with

red color is the one that is newly introduced. The automatic configuration of the physical Cell

ID for the new cell proceeds as follows:

1. When the procedure starts, the new cell starts a timer for this configuration phase.


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2. A set of Physical Cell IDs is defined as a set of temporary Physical Cell IDs. The new

cell picks one temporary Physical Cell ID randomly.

3. According to ANR (Automatic Neighbor Relation) function, UE reports those detected

cells with their Physical Cell IDs to its serving cell. So the cells around the new cell

receive the report of the new cell and the new cell receives the report of its surrounding

cells. By ANR function, they also get the Global Cell ID of those reported cells.

Figure 0-5 Physical Cell ID Deployment

Figure 6.5: Physical Cell ID deployment

4. The new cell adds those reported cells to its neighbour cell list. It also looks up the IP

addresses of those neighbor cells and establishes the X2 connection if necessary.

5.

Those cells, which receive the report of the new cell, adds the new cell in their neighborcell list, look up the IP address of the new cell and establish the X2 connections if

necessary. Which trigger the X2 connection setup, the new cell or the surrounding cells,

depends on which one detects the neighborhood relation first.

6. After X2 connection is set up, the surrounding cells exchange their neighbor cell lists

with the new cell. As a result, the new cell also gets the neighbor relation information of

its neighbor cells.

7. When the timer times out, the new cell collect all the information it gets, which includes

its neighbor cell list and the neighbor cell lists of its neighbor cells. Then the new cell

selects one Physical Cell ID that satisfies the two criteria, which has been explained

before.8. The new cell informs its neighbor cells that it has changed its Physical Cell ID .Those

neighbor cells updates their neighbor relation table accordingly. During the configuration

phase, some collisions may also happen. For example, two new cells select the same

temper Physical Cell ID and they are neighbors. The collision will be detected during the

configuration procedures and one of the configuration procedures will be restarted.


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6.4.7 16-QAM uplink and 64-QAM Downlink

Under ideal transmission conditions, for example, when clear LOS exists between sender and

receiver over very short distances, 64-QAM is used, which codes six bits on a single subcarrier.

Under harsher conditions, less demanding modulation schemes like 16-QAM [6].

Higher-order modulation enables high peak data rates to be achieved in scenarios with high SIR,

such as in indoor hotspot cells. Multiple-input multiple-output (MIMO) antenna operation

making HSDPA the first standardized cellular system to support the transmission of multiple

data streams to each UE by means of multiple antennas at each end of the radio link. MIMO

aims to exploit spatial multiplexing gain by making positive use of the multiple propagation

paths to separate different data streams transmitted simultaneously using the same frequency and

code [6].

6.4.8 Dual Band Support

Enables the use of spectrum resources on two bands with one Digital Unit (DUL), it supports

the configuration of up to 6 cells with two different carrier frequencies and bandwidths, for

example Band 4 and Band 7 .

6.4.9 Support for 15km CPRI Link

CPRI Link Increases support for long optical fiber between Radio and Baseband to 15 km. When

using optical fiber and optical Small Form Factor Plugins (SFPs) the length of the optical fiber

between the DUL and the radio can be up to 15 km long. It is possible to mix long and short

fibers as long as no fiber distance exceeds the maximum distance [13].

6.4.10 System Information Modification

This feature makes it possible to modify the System Information broadcasted in the cell without

doing a lock/unlock operation on the cell [13].

An operator will need to tune the LTE coverage when building it out and hence change neighbor

relations and re-selection thresholds. With this feature, such changes can be done withoutdisturbing the service .This gives the operator the possibility to change parameters in the system

information, for example, cell selection related parameters, without affecting the in service

performance [6].


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6.4.11 Enhanced Observability

This feature provides the operator with increased visibility in network performance statistics,

enabling more diverse monitoring of the LTE RAN.

The statistical granularity, including averages, peak/min values and distributions of key events

and procedures, is increased within in the areas of Accessibility, Retain ability, Integrity,

Mobility and Availability. New utilization type measurements, such as procedure times and

processor load, are also introduced [17]


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7 Site Specific Propagation ModelIn previous chapters we have complete LTE planning using Cost Hata propagation model. Other

propagation models can be used which are more efficient and accurate than cost Hata. Models

that will be studied are Hata and full 3D propagation model. This chapter includes four sections

the first section is dissection about Hata, Cost and Full 3D model, the second one is a description

for the tool that we used ,then in the third section our design description finally in the last sectionsummarize our results .

7.1 propagation models

Propagation models have been developed to be able to estimate the radio wave propagation as

accurately as possible. Models have been created for different environments to predict the path

loss between the transmitter and receiver. How much power needs to be transmitted using the

BTS to be able to receive certain power level from the MS? The complexity of the model affects

the applicability as well as the accuracy. Two well-known models are those of Okumura – Hataand cost Hata. The first mentioned is created for large cells, i.e. for rural and suburban areas [3],

while the CostHata model is an enhanced version of Okumura hat model that includes 1800_

1900 MHZ [18].

7.1.1 Hata Model (Okumura Hata Model)

Hata's propagation model is the basis for several widely used propagation models in the cellular

industry. The main attraction of Hata's model is its simplicity, and its main drawback is its

constraints on the ranges of some parameters [19].

The Okumura-Hata model is a well- known propagation model, which can be applied for a

macro cell environment to predict median radio signal attenuation. Having one component the

model uses free space loss. The Okumura-Hata model is an empirical model, which means that it

is based on field measurements [3]. Hata derived empirical formulas for propagation path loss

based on Okumura's report containing graphs such as median field strength versus distance. This


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empirical model simplifies calculation of path loss because it is a closed-form formula and is not

based on empirical curves for the different parameters [19].

Hata's basic model includes path loss for an urbanenvironment and provides correction factors

for other environments, such as suburbanand open areas. Caution should be exercised while

using Hata's model because it isvalid only for specific cases. Hata's model makes the followingassumptions: pathloss is between isotropic antennas and the terrain is quasi-smooth and regular

[19].

7.1.2 Cost Hata Model

Hata's basic model is valid in the frequency range of 150-1500 MHz. European COST 231

extended the validity of Hata's model to higher frequencies by analyzing Okumura's propagation

graphs in the upper frequency band [19]

CostHata model is also known as COST-231 Hata model. It is the extension of Hata model

(Okumura Hata model) and it can be used for the frequencies up to 2000 MHz [20].

This model predicts the signal strength from empirical formulas which uses different correction

factors for different environments which is based on field measurements taken by Okumura in

Japan. Statistical formulas and correction factors of the model were derived from observation

and analysis of the measured propagation data. From the measurements, Okumura generated a

family of curves to predict propagation loss for various situations. Okumura also included

various loss factors to account for urban losses: street orientations, terrain, mixed land and sea

paths. Sometimes, it is not reliable to use these curves due to inherent vagueness of the

conditions of the correction factors. Despite their simplicity the curves are cumbersome to use

wireless system planning. In a subsequent study, Hata was able to fit empirical formulas to

Okumura's curves to efficiently incorporate them into computer programs [20].

The COST-Hata model is valid for small and large macrocells in which the BS antenna heights

are above rooftop levels in the vicinity of the BS. This model is widely used in the industry for

cell coverage area prediction and for cellular system performance analysis. This model is

unsuitable for microcells [19].

7.1.3 Full 3D Propagation Model

The Full 3D model is the only one of Wireless InSite‟s propagation models whih plaes no

restriction on object shape; it allows buildings to have sloped roofs. It is also the only model


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which includes transmission through surfaces. For this reason, it is the only ray-based model

which can be applied to indoor environments. When transmissions are included, all facets, except

those comprising the terrain and foliage, should typically be doubled-sided [21].

Full 3D model Take into account number of reflections, diffractions and transmissions .but other

models not.

The following are the specification of Full 3D Model [21]

Maximum reflections: 30 (assuming no transmissions)

Maximum transmissions: 30 (assuming no reflections)

Maximum diffractions: 4 (SBR), 3 (Eigenray)

Environments: all

Terrain: all

Urban: all

Foliage: direct waves, no lateral wave

Objects: all

Range: depends on application

Antenna heights: all

Antenna types: all

Ray tracing: SBR or Eigenray

Minimum frequency: 100 MHz

Maximum frequency: depends on application

7.1.3.1 Cell ular Propagation Mechanisms

As mentioned previously Full 3D model Take into account number of reflections and diffractions

, this sub-section explain these mechanisms.

In cellular communications, the actual path loss experiencedby a cellular radio signal is usually

much higher than the free-space path loss. Raytheory is widely used for analyzing radio wave

propagation. Several rays can beviewed as a single entity. As this single entity or a set of rays

propagates from thetransmitter to the receiver, four basic mechanisms influence the overall path

lossexperienced by the radio signal: reflection, diffraction, scattering, and absorption

orpenetration [19].

1. Reflection

When an electromagnetic wave encounters an object that has large dimensions comparedto the

wave's wavelength, reflection occurs. The receiver in such a case couldreceive a direct LOS


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signal and a reflected path from the transmitter. The buildingsin an urban environment, the

mountains in an open environment, and the earth'ssurface are examples of objects that cause

reflections of the RF wave. When the RFwave traveling in one type of medium (e.g., the air)

impinges upon an object thatrepresents another type of medium, part of the energy may be

reflected back into thefirst medium, part of the energy may be absorbed by the second medium,

and partof the energy may continue to flow in a wave propagating into the second medium [19].

In a cellular radio environment, a propagation model that considers a direct pathand a ground-

reflected path, gives a more accurate predictionthan the model that considers only the direct path

[19].

2. Diffraction

When an electromagnetic wave encounters an object with sharp irregularities, such as edges, it

bends around the object. This effect is called diffraction, and it enables signal propagation in the

absence of LOS and behind obstacles. The signal strength starts to decrease quickly in theshadowed region behind obstacles, the points on a wavefront encountering an obstacle act as

sources of secondary waves that become a new wavefront, facilitating propagation in thein

theshadowed region [19].

7.2 Tool Description

The tool we used to obtain our results is Wireless InSite .This section provide a brief description

of the tool [21].

Wireless InSite is a powerful electromagnetic modeling tool for predicting the effects of

buildings and terrain on the propagation of electromagnetic waves. It predicts how the locations

of the transmitters and receivers within an urban area affect signal strength. Wireless InSite

models the physical characteristics of the rough terrain and urban building features, performs the

electromagnetic calculations, and then evaluates the signal propagation characteristics [21].

Important elementsof a Wireless InSite project shown in figure 7.1 are explained below

Figure 7.1 Wireless InSite elements


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7.2.1 Features

A feature comprises all the building or terrain data loaded from a single file. Each feature is

subdivided into structure groups, structures, sub-structures and faces. In addition to the

geometrical data, features also contain data on the material properties of each face. The set ofmaterial properties are referred to olletively as “material types,” and the properties and editing

options for these can be accessed from the Main window or the Project [21].

7.2.2 Study areas

This tab lists all study areas in the project. Study areas serve several purposes. First, they can be

used to define a region of the modeled environment and then to limit all computations to the

buildings, terrain features and Tx/Rx locations within the study area. Different propagation

models can then be applied within each study area. Second, as an organizational tool they makeit possible to keep predictions made with different parameters separate from each other. The user

can create as many study areas as desired [21].

7.2.3 Transmitters

Transmitter locations and properties are defined by transmitter sets. Transmitter sets contain one

or more transmitter locations. In addition to the geographical location of the site, the transmitter

set also includes antenna type, the direction of the antenna beam, the radiated power and the

waveform assigned to each set. The types of transmitter sets are points, routes, circular arcs,rectangular grids, polygons, circular cylinders, vertical surfaces and user-defined data files [21].

7.3.4 Receivers

Receiver locations and properties are defined by receiver sets. Receiver sets also includes

antenna type, the direction of the antenna beam, and the waveform assigned to each set. The

types of receiver sets are points, routes, circular arcs, rectangular grids, polygons, circular

cylinders and user-defined data files [21].

7.3.5 Materials

The electromagnetic interactions of each face are determined by the material properties assigned

to the face. The display properties, such as the color and in some cases the thickness, are also

part of the material definition [21].


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7.3.6 Antennas

To perform propagation calculations using Wireless InSite, the model requires both transmitters

and receivers, each with an associated waveform, and antenna. When an antenna is added to a

project and its parameters are set using the Antenna Properties dialog box. An antenna can beused in multiple instances by associat

Lte Planning and Specific Propagation Model Selection (1)

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