Lte radio netwok planning

Long Term Evolution (LTE)
Radio Access Network Planning Guide

Long Term Evolution (LTE)
Radio Access Network Planning Guide
1 How to Use This Guide ..............................................................................................................................1
1.1 Introduction ...............................................................................................................................................1
1.2 General Radio Network Planning Process ....................................................................................................1
1.3 Quick Guide to Content of Each Section .....................................................................................................2
2 LTE Fundamentals Key Technologies .......................................................................................................3
2.1 Overview of Data Market as a Whole ..........................................................................................................3
2.2 3GPP Evolution and Market Expectation .....................................................................................................3
2.3 LTE Modulation Technology Highlight .........................................................................................................4
2.3.1 OFDM Fundamental .....................................................................................................................................................................5
2.3.2 SC-FDMA Fundamental ................................................................................................................................................................7
2.4 LTE Frame Structure ....................................................................................................................................8
2.5 LTE Resource Block Architecture ..................................................................................................................9
2.6 Reference Signal Structure ........................................................................................................................10
2.7 Timing and Sampling Architecture ............................................................................................................11
2.7.1 Normal and Extended Cyclic Prefix .............................................................................................................................................12
2.7.2 Synchronization Channel ............................................................................................................................................................13
2.8 Uplink Physical Channel Structure .............................................................................................................13
2.8.1 FDD Uplink Control, Sounding and Demodulation Reference Signal Structure ............................................................................14
2.9 Multiple Input Multiple Output (MIMO) ....................................................................................................15
2.9.1 3GPP MIMO Mode Definition .....................................................................................................................................................15
2.9.2 Open Loop MIMO ......................................................................................................................................................................16
2.9.3 Closed Loop MIMO ....................................................................................................................................................................17
2.9.4 Pre-coding Matrix ......................................................................................................................................................................18
2.9.5 Beam Forming ...........................................................................................................................................................................20
2.10 LTE FDD vs LTE TDD Main Features Comparison ......................................................................................21
2.11 LTE Channels Hierarchy Overview ............................................................................................................22
2.11.1 Physical Channel Modulation Schemes .....................................................................................................................................22
2.11.2 Downlink Channel Functionality Breakdown .............................................................................................................................23
2.11.3 Uplink Channel Functionality Breakdown .................................................................................................................................23
2.11.4 Channel Functionality Description in Detail ...............................................................................................................................23
2.11.5 Downlink Control Channel and RE Mapping Relationship .........................................................................................................25
2.12 Cell Search, Synchronization Mobility–UE Call Flow View .....................................................................25
2.12.1 Cell Search and Synchronization ...............................................................................................................................................25
2.12.2 UE Procedure for Reporting Channel Quality Indication (CQI), Precoding Matrix indicator (PMI) and rank indication (RI) ...........26
2.12.3 System Information Bit Definition .............................................................................................................................................27
2.12.4 Mobility Management ..............................................................................................................................................................27

2.12.5 EUTRAN Hierarchy and Interface Overview ...............................................................................................................................27
2.12.6 Summary of Handover Call Flow – 3GPP Example TS36.300 .....................................................................................................28
2.13 Example of Peak Data Rate Calculation ...................................................................................................29
3 LTE Frequency and Spectrum Planning .....................................................................................................30
3.1 Frequency Spectrum Overview - FDD ........................................................................................................30
3.2 Frequency Spectrum Overview - TDD ........................................................................................................30
3.3 Channel Bandwidth and Subcarrier Allocation ...........................................................................................31
3.4 Channel Arrangement ...............................................................................................................................32
3.4.1 Channel Spacing ........................................................................................................................................................................32
3.4.2 Channel Raster ...........................................................................................................................................................................32
3.4.3 Carrier Frequency and EARFCN ...................................................................................................................................................33
3.5 Frequency Planning Recommendations .....................................................................................................34
3.5.1 Conventional Frequency Reuse Scheme 1*3*1 ............................................................................................................................34
3.5.2 SFR 1*3*1 – Downlink and Uplink ..............................................................................................................................................35
3.5.3 TDD Specific Frequency Planning Considerations ........................................................................................................................36
3.5.4 Frequency Band Selection ..........................................................................................................................................................37
3.5.5 Cyclic Prefix Planning .................................................................................................................................................................38
3.5.6 Placing Multiple Technologies@Multiple Frequency Band ...........................................................................................................38
4 Link Budget and Coverage Planning .........................................................................................................40
4.1 Conventional Link Budget .........................................................................................................................41
4.2 Propagation Parameters ............................................................................................................................42
4.2.1 Channel Model ..........................................................................................................................................................................42
4.2.2 3GPP Value for Multipath and Doppler Effect .............................................................................................................................43
4.2.3 Propagation Model ....................................................................................................................................................................45
4.2.4 Penetration Loss .........................................................................................................................................................................50
4.2.5 Body Loss ...................................................................................................................................................................................51
4.2.6 Feeder Loss ................................................................................................................................................................................52
4.2.7 Background Noise ......................................................................................................................................................................53
4.3 Equipment-Related Parameters .................................................................................................................53
4.3.1 Transmit Power ..........................................................................................................................................................................53
4.3.2 Receiver Sensitivity .....................................................................................................................................................................54
4.3.3 Noise Figure ...............................................................................................................................................................................54
4.3.4 Antenna Gain .............................................................................................................................................................................54
4.4 LTE-Related Parameters .............................................................................................................................56
4.4.1 MIMO Gains ..............................................................................................................................................................................56
4.4.2 Cell Edge Rate ............................................................................................................................................................................57
4.4.3 Interference Margin ...................................................................................................................................................................59
4.4.4 Beam Forming ...........................................................................................................................................................................59
4.5 System Reliability ......................................................................................................................................60
4.5.1 Slow Fading Margin ...................................................................................................................................................................60
4.5.2 Effect of Earth Curvature ............................................................................................................................................................62
4.5.3 Absence of Fast Fading and Soft Handover Margin ....................................................................................................................62

4.6 Specific Factors in Link Budget Consideration ............................................................................................62
4.6.1 Features Overview ......................................................................................................................................................................62
4.6.2 TTI Bundling ...............................................................................................................................................................................63
4.6.3 Interference Rejection Combining ..............................................................................................................................................63
4.6.4 Reference Signal Power Boosting Gain .......................................................................................................................................65
4.6.5 Remote Radio Unit and eNodeB Portfolio ...................................................................................................................................65
4.7 Summary of Variables inside Link Budget Tools .........................................................................................65
5 Interference and Guard Band Analysis ......................................................................................................69
5.1 Overview ..................................................................................................................................................69
5.1.1 Basic Concepts ...........................................................................................................................................................................69
5.1.2 Analysis of Background Noise ....................................................................................................................................................73
5.1.3 Impact of Interference ...............................................................................................................................................................74
5.2 Interference Between TDD Systems ...........................................................................................................75
5.2.1 Interference between Different Carriers ......................................................................................................................................75
5.2.2 Interference within the Same Carrier ..........................................................................................................................................76
5.2.3 Theoretical Analysis of Interference under Site Sharing ...............................................................................................................77
5.2.4 Theoretical Analysis of Interference: Non Colocated eNodeB .....................................................................................................78
5.3 Guard Band Requirement: LTE-FDD vs GSM/UMTS ....................................................................................79
5.4 GuardBand Requirement: LTE FDD vs LTE TDD ..........................................................................................79
5.5 Spectrum Refarming for LTE ......................................................................................................................80
5.5.1 Summary ...................................................................................................................................................................................80
5.5.2 GSM Spectrum Refarming ..........................................................................................................................................................80
5.5.3 Introduction of Buffer Zone ........................................................................................................................................................81
5.6 Radio Access Technologies Co-location Strategies .....................................................................................82
5.6.1 Overview ...................................................................................................................................................................................82
5.6.2 GSM-LTE Co-Location Examples .................................................................................................................................................82
5.6.3 LTE TDD and WiMAX Systems Co-Location .................................................................................................................................87
6 LTE Access Network Capacity Planning .....................................................................................................89
6.1 Definition of Capacity ...............................................................................................................................89
6.2 3GPP Services Classification ......................................................................................................................91
6.3 EUTRAN Capacity Limiting Factors ............................................................................................................91
6.3.1 Operating Frequency Band .........................................................................................................................................................92
6.3.2 RF coverage - RSRP ....................................................................................................................................................................93
6.3.3 Impact of Interference on Capacity ............................................................................................................................................93
6.3.4 Signal Interference Noise Ratio and Adaptive Coding .................................................................................................................94
6.3.5 Radio (Transmitter) Power Availability .........................................................................................................................................94
6.3.6 Spectrum Bandwidth Availability ................................................................................................................................................94
6.3.7 Base Band Channel Card Processing Capacity .............................................................................................................................94
6.3.8 S1/X2 Capacity ...........................................................................................................................................................................94
6.3.9 Application of Special Antenna Technologies (MIMO/BF/V MIMO) ..............................................................................................94
6.3.10 Scheduling Mode .....................................................................................................................................................................95
6.3.11 Actual Cell Site Placement in Relation to Traffic ........................................................................................................................96

6.3.12 UE Capability ............................................................................................................................................................................96
6.3.13 User Traffic Mix and Call Modelling ..........................................................................................................................................97
6.3.14 Time Slot Allocation for Uplink and Downlink – TDD specific ....................................................................................................97
6.3.15 Cyclical Prefix Allocation ...........................................................................................................................................................98
6.4 S1 Bandwidth Dimensioning Procedure .....................................................................................................98
6.5 X2 Bandwidth Dimensioning Procedure ....................................................................................................99
6.6 Impact of Latency of X2 on Cell Throughput ...........................................................................................100
6.7 Inter Radio Access Technology Handover Considerations ........................................................................100
7 U-Net Simulation and Operation ............................................................................................................103
7.1 Introduction ............................................................................................................................................103
7.2 Simulation Process ..................................................................................................................................103
7.3 Creating Project ......................................................................................................................................104
7.4 Geographical Information .......................................................................................................................104
7.4.1 Quick Import Function .............................................................................................................................................................104
7.4.2 Defining Coordinate Systems ....................................................................................................................................................105
7.4.3 Properties of Clutter Class ........................................................................................................................................................106
7.5 Equipment Parameter .............................................................................................................................107
7.5.1 Overview .................................................................................................................................................................................107
7.5.2 Network Settings .....................................................................................................................................................................107
7.5.3 Equipment ...............................................................................................................................................................................113
7.5.4 Site, Cell and Transmitter Listing ..............................................................................................................................................113
7.5.5 Viewing “Hidden” Parameters ..................................................................................................................................................115
7.5.6 Propagation Model Selection ...................................................................................................................................................115
7.5.7 Clutter Related Modelling ........................................................................................................................................................118
7.5.8 Impact of Parameter Setting on Prediction and Simulation .......................................................................................................118
7.6 Engineering Parameter ............................................................................................................................119
7.6.1 Power Setting ..........................................................................................................................................................................119
7.6.2 Load Setting ............................................................................................................................................................................121
7.6.3 Frequency Planning ..................................................................................................................................................................122
7.6.4 Scheduling Parameters .............................................................................................................................................................125
7.6.5 Antenna Property .....................................................................................................................................................................126
7.6.6 Properties of a Single Transmitter .............................................................................................................................................128
7.6.7 Properties of a eNodeB Template .............................................................................................................................................130
7.7 LTE Traffic Model Parameters ..................................................................................................................132
7.7.1 Overview .................................................................................................................................................................................132
7.7.2 Environments ...........................................................................................................................................................................132
7.7.3 User Profiles .............................................................................................................................................................................133
7.7.4 Terminals .................................................................................................................................................................................134
7.7.5 Mobility Types ..........................................................................................................................................................................135
7.7.6 Services ....................................................................................................................................................................................136
7.7.7 Traffic Map ..............................................................................................................................................................................137
7.8 Prediction and Simulation .......................................................................................................................141
7.8.1 Predictions ...............................................................................................................................................................................141

7.8.2 Simulation ................................................................................................................................................................................145
7.9 Point Analysis Tool ..................................................................................................................................151
7.9.1 Profile ......................................................................................................................................................................................151
7.9.2 Reception ................................................................................................................................................................................151
7.9.3 Signal Analysis .........................................................................................................................................................................152
7.9.4 Result ......................................................................................................................................................................................152
7.10 RF Cell Planning Optimization ...............................................................................................................152
7.11 U-Net Planning Case .............................................................................................................................154
7.11.1 Overview of Planning Area .....................................................................................................................................................154
7.11.2 Site Distribution .....................................................................................................................................................................155
7.11.3 Parameter Configuration and General Assumption .................................................................................................................156
7.11.4 Network Coverage Predictions ...............................................................................................................................................157
7.11.5 Network Capacity Simulation .................................................................................................................................................160
8 LTE Network Key Performance Indicators ...............................................................................................163
8.1 KPI Measurement Methodology ..............................................................................................................163
8.2 KPI Acceptance Procedure ......................................................................................................................163
8.3 Service KPIs and Network KPIs ................................................................................................................164
8.4 Cluster and Test Route ............................................................................................................................164
8.5 Proposed Key Performance Indicators .....................................................................................................165
8.6 Proposed KPIs for Final Acceptance (Stability Acceptance, Optional) .......................................................165
9 Network Planning Checklist ...................................................................................................................166
9.1 Introduction ............................................................................................................................................166
9.2 Checklist Items Consideration .................................................................................................................166
9.2.1 Understanding Customer Spectrum Bandwidth Availability .......................................................................................................166
9.2.2 Actual Frequency Band Allocation for LTE .................................................................................................................................166
9.2.3 Frequency Band Refarming Requirement for LTE ......................................................................................................................167
9.2.4 Location of Customer Coverage Requirement ...........................................................................................................................167
9.2.5 Highway and Tunnel Coverage Requirement ............................................................................................................................168
9.2.6 Evaluate Existing Network Condition for InterRAT ....................................................................................................................168
9.2.7 Terrain and Clutter Database Availability and Accuracy .............................................................................................................168
9.2.8 Scheduler Selection ..................................................................................................................................................................169
9.2.9 Indoor Coverage Requirement .................................................................................................................................................169
9.2.10 Cell Edge Throughput Requirement ........................................................................................................................................169
9.2.11 Call Model and SmartPhone Penetration Growth Considerations ............................................................................................169
9.2.12 Base Station Antenna and Other Co-siting Equipment Selection .............................................................................................170
9.2.13 Interference Protection and Isolation Requirement .................................................................................................................170
9.2.14 Radio Related Equipment Selection ........................................................................................................................................171
9.2.15 Network and Spectrum Evolution Consideration ....................................................................................................................171
9.2.16 MIMO and Beam Forming Implementation ............................................................................................................................171
9.2.17 Cyclic Prefix Planning .............................................................................................................................................................171
9.2.18 Understanding of Current Transmission Backhaul Network Capability .....................................................................................172
9.2.19 UE Distribution and Channel Model : Pedestrian vs High Mobility ...........................................................................................172

9.2.20 TDD Specific Uplink and Downlink Configuration ...................................................................................................................172
9.2.21 Power Boosting Configuration ...............................................................................................................................................172
10 Appendix: RF Antenna Systems ..............................................................................................................174
10.1 Overview ..............................................................................................................................................174
10.2 Antenna Classification ..........................................................................................................................174
10.2.1 Frequency ..............................................................................................................................................................................174
10.2.2 Directivity ...............................................................................................................................................................................174
10.3 Main Specifications of Antenna ............................................................................................................174
10.3.1 Work Band .............................................................................................................................................................................175
10.3.2 Antenna Gain .........................................................................................................................................................................175
10.3.3 Antenna Pattern .....................................................................................................................................................................176
10.3.4 Beamwidth ............................................................................................................................................................................177
10.3.5 Relation between Beamwidth and Gain .................................................................................................................................177
10.3.6 Front-to-rear Ratio .................................................................................................................................................................178
10.3.7 Upper Side Lobe Suppression .................................................................................................................................................178
10.3.8 Polarization Mode ..................................................................................................................................................................179
10.3.9 Down Tilt ...............................................................................................................................................................................179
10.3.10 VSWR (Voltage Standing Wave Ratio) ...................................................................................................................................179
10.3.11 Port Isolation .......................................................................................................................................................................180
10.3.12 Power Capacity ....................................................................................................................................................................180
10.3.13 Input Port of Antenna ..........................................................................................................................................................180
10.3.14 Passive Intermodulation (PIM) ..............................................................................................................................................180
10.3.15 Dimensions and Weight of Antenna .....................................................................................................................................181
10.3.16 Wind Load ...........................................................................................................................................................................181
10.3.17 Work Temperature and Humidity .........................................................................................................................................181
10.3.18 Lightning Protection .............................................................................................................................................................181
10.3.19 Three-proof Capability ..........................................................................................................................................................181
10.3.20 Camouflaged Antenna Scheme for Sites ...............................................................................................................................181
10.3.21 Customized Camouflage ......................................................................................................................................................182
10.3.22 Outlook Camouflage ............................................................................................................................................................183
10.3.23 Antenna Camouflage in Special Environment .......................................................................................................................183
11 References ...........................................................................................................................................184

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1.1 Introduction
The purpose of this document is to provide systems engineers/planners with a set of guidelines and introductions to
LTE deployment planning that may aid the design of a high quality Long Term Evolution (LTE) RF System. In general,
most of the content provided in this planning guide can be applied to LTE system design with field implementation
considerations. Specific RF planning information unique to Huawei’s LTE EUTRAN product is also provided.
Although there are numerous and detailed references made to particular tools, it is not the purpose of this planning
document to replace any product and tools' operating manual/instruction. Please refer to the official publications of
the respective product/tool for their most up to date functionality.
1.2 General Radio Network Planning Process
The flow diagram below shows one of the more common work procedures recommended by the Radio network
planning team. It covers all the major area that requires technical attention from the conceptual beginning of a
network design to the provisioning of final network parameters required for the deployment phases.
1 How to Use This Guide

2
1.3 Quick Guide to Content of Each Section
The LTE RF Planning Guide is a collection of fairly independent chapters covering various aspects of LTE system RF
design and implementation. The table below outlines the key features of each Chapter.
Chapter # Chapter Title Detailed Description
1 How to Use this Guide Understand the contents of this document.
2
LTE Fundamentals
Key Technologies
Learn LTE fundamental which includes PHY and MAC layer technology.
Meanwhile, some key LTE technologies such as MIMO and FFR will be presented
in this section.
3
Frequency and
Spectrum Planning
Overview of LTE Spectrum definition as in 3GPP. Understanding the various reuse
options available to LTE as well as band selection and combination overview
4
Link Budget and
Coverage Planning
Understand the parameters that comprise the LTE RF Link Budget. Learn about
some of the basic propagation models as well as critical features that affect link
budget values.
5
Interference, Guard
band and Refarming
Analysis
Understand some basic concept for interference analyze such as ACS, ACLR, etc.
Learn different interference between two different systems among serials TDD
and FDD system.
6
LTE Access Network
Capacity Planning
Overview of LTE capacity planning as well as highlight all the critical factors and
considerations that will affect capacity for an LTE network.
7
U-Net Simulation and
Operation
Understand U-Net operations. Learn definition of different parameters such as
equipment parameters, engineering parameters, traffic model parameters, etc.
High level view on how to predict and simulate based on U-Net.
8
LTE Network Key
Performance
Indicators
Provide LTE KPIs classification and KPI Acceptance Procedure
9
Network Planning
Checklist
Provide a list of items that Planning engineers need to consider and ideally have
answers from customer before performing any detail planning.
Table 1-1 Quick Guide

3
2 LTE Fundamentals Key Technologies
2.1 Overview of Data Market as a Whole
Challenges: Limited Investment but 500x Capacity Increment
2.2 3GPP Evolution and Market Expectation
Source: Global mobile Suppliers Association – October 2010

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2.3 LTE Modulation Technology Highlight
In Nov. 2004, 3GPP began a project to define the long-term evolution (LTE) of Universal Mobile Telecommunications
System (UMTS) cellular technology. The main goal is to provide
Higher throughput performance••
100 Mbit/s peak downlink, 50 Mbit/s peak uplink••
1G for LTE Advanced••
Higher cell edge performance••
Reduced latency in setup time. Shorter transfer delay, shorter handover latency and interruption time for better••
user experience
Support of variable and scalable bandwidth (1.4, 3, 5, 10, 15 and 20 MHz)••
Backwards compatible with Existing 3G technologies••
Works with GSM/EDGE/UMTS systems••
Utilizes existing 2G and 3G spectrum and new spectrum••
Supports hand-over and roaming to existing mobile networks••
Quality of Service Support.••
Wide application••
TDD (unpaired) and FDD (paired) spectrum modes••
Mobility up to 450km/h••
Large range of terminals (phones and PCs to cameras)••
LTE employs Orthogonal Frequency Division Multiple Access (OFDMA) for downlink data transmission and Single
Carrier FDMA (SC-FDMA) for uplink transmission.
It is also important to remember that LTE systems operate in two separate domains, namely time and frequency as
shown in the figure below for downlink.

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Figure below is the LTE uplink allocation structure from a time and frequency perspective.
2.3.1 OFDM Fundamental
OFDM was selected for the downlink because it can
Improved spectral efficiency••
Reduce ISI effect by multipath••
Provide better Protection against frequency selective fading••
OFDM is a scheme that offers good resistance to multipath and is now widely recognized as the method of choice
for mitigating multipath for broadband wireless. It can be straightforwardly extended to a multi-access scheme called
OFDMA, where each user is assigned a different set of subcarriers.
I. Frequency Spectral Efficiency Improvement
OFDM increases spectral efficiency by incorporating multiple carriers in the same frequency space as a single carrier.

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II. Reducing the Impact by Inter Symbol Interference (ISI)
Improvement of frequency spectral efficiency requires the reduction of Inter symbol interference (ISI). This is achieved
by tighter frequency roll off and alignment of nulls and peaks between different frequencies.
III. Better Protection Against Frequency Fading
Smaller subcarrier and resource block bandwidth increase robustness against frequency related fading
With this smaller carrier bandwidth, the frequency coherence bandwidth is much smaller than 3G systems while and
correlation factor is much higher. As a result, it will also be much easier to implement scheduling algorithm based on
Frequency Selective Scheduling to improve system throughput in the manner shown below.

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2.3.2 SC-FDMA Fundamental
Single Carrier-FDMA is a recently developed single carrier multiple access technique which has similar structure and
performance to OFDMA. SC-FDMA can be viewed as a special OFDMA system with the user’s signal pre-encoded by
discrete Fourier transform (DFT), hence also known as DFT-pre-coded OFDMA or DFT-spread OFDMA. One prominent
advantage of SC-FDMA over OFDMA is the lower PAPR (peak-to-average power ratio) of the transmit waveform for low-
order modulations like QPSK and BPSK, which benefits the mobile users in terms of battery life and power efficiency.
OFDM signals have a higher peak-to-average ratio (PAR)—often called a peak-to-average power ratio (PAPR)—than
single-carrier signals do. The reason is that in the time domain, a multicarrier signal is the sum of many narrowband
signals. At some time instances, this sum is large and at other times is small, which means that the peak value of
Frequency Selective Fading Resistance

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the signal is substantially larger than the average value. This high PAR is one of the most important implementation
challenges that face OFDM, because it reduces the efficiency and hence increases the cost of the RF power amplifier,
which is one of the most expensive components in the radio. The figure below shows the relationship between OFDM
and SC-FDMA in LTE.
The major difference between the downlink and uplink transmission scheme is that each subcarrier in the uplink carries
information about each transmitted modulation symbol as shown in figure below, whereas in downlink each subcarrier
only carries information related to one specific modulation symbol. As a result, the uplink power level due to SC-FDMA
also need to be increased by 2~3dB to compensate for the extra noise due to more spreading.
2.4 LTE Frame Structure
The figure below shows the frame structure for LTE under Time division mode (TDD) Type 2 and Frequency Division
mode (FDD) Type 1. Main differences between the two modes are
Frame 0 and frame 5 (always downlink in TDD)••
Frame 1 and frame 6 is always used as for synchronization in TDD••
Frame allocation for Uplink and Downlink is settable in TDD••
The sampling rate in both FDD and TDD is the same and both technologies operate under a 1-ms sub-frame (TTI-
Transmission Time Interval) and 0.5us timeslot definition.
The first 3 configurations (0-2) for TDD can also be viewed as 5ms allocation due to repetition. The figure below shows
a detailed relationship between rates and frame structure.

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2.5 LTE Resource Block Architecture
The building block of LTE is a physical resource block (PRB) and all of the allocation of physical resource blocks (PRBs) is
handled by a scheduling function at the 3GPP base station (eNodeB). In summary,
One frame is 10ms and it consists of 10 sub-frames••
One subframe is 1ms and contains 2 slots••
One slot is 0.5ms in time domain and each 0.5ms assignment can contain N resource blocks [6 N 110]••
depending on the bandwidth allocation and resource availability.
One resource block is 0.5ms and contains 12 subcarriers for each OFDM symbol in frequency domain.••
There are 7 symbols (normal cyclic prefix) per time slot in the time domain or 6 symbols in long cyclic prefix.••
Resource element is the smallest unit of resource assignment and its relationship to resource block is shown as below
from both a timing and frequency perspective.

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2.6 Reference Signal Structure
Reference signal is the “UMTS Pilot” equivalent and it is used by UE to predict the likely coverage condition on offer for
each of the eNodeB cell received. The figure below shows the locations of the reference signal within each sub-frame
when transmit antennae are used by the cell.

11
As LTE is a MIMO based technology, it can have more than two transmit antennae and in order to avoid reference
signals from the same cell interfering with each other, different antennae will be transmitting reference signal at
different time and frequency and how these are allocated are shown below.
As defined in the standard for TDD operations, the channel-sounding mechanism involves the UE’s transmitting a
deterministic signal that can be used by the eNodeB to estimate the UL channel from the UE. If the UL and DL channels are
properly calibrated, the eNodeB can then use the UL channel as an estimate of the DL channel, due to channel reciprocity.
2.7 Timing and Sampling Architecture
Sampling frequency varies under different bandwidth configuration in LTE and the table below summarizes the possible
combinations.
A quick summary of all the physical layer information for LTE is shown below.

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2.7.1 Normal and Extended Cyclic Prefix
The key to making OFDM realizable in practice is the use of the FFT algorithm, which has low complexity. In order for
the IFFT/FFT to create an ISI-free channel, the channel must appear to provide a circular convolution. Adding cyclic
prefix to the transmitted signal to create a signal that appears to be just like circular convolution and this is done by
copying the last part of each OFDM symbol to the front of each symbol with the length of a guard interval, to form a
cyclic prefix (CP).
Also, to prevent the guard interval from destroying the inter-sub-carrier orthogonality, the delay of each path should
not exceed the guard interval where the number of waveforms within the integral time of the FFT is an integer
The cyclic prefix, although elegant and simple, is not entirely free. It comes with both a bandwidth and power penalty.
Since redundant symbols are sent, the required bandwidth for OFDM also increases. Similarly, an additional symbol
must be counted against the transmit-power budget. Hence, the cyclic prefix carries a power penalty of v dB in addition
to the bandwidth penalty. In summary, the use of the cyclic prefix entails data rate and power losses. The “wasted”
power has increased importance in an interference-limited wireless system, causing interference to neighboring users.

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Where L is the power used for non CP transmission. In the case where there is a large delay spread, e.g. due to large
cell radius, an extended CP option can be used.
2.7.2 Synchronization Channel
The diagram below shows the relative position of Primary Synchronization (PSS) and Secondary Synchronization (SSS)
within the radio frame in a FDD LTE system.
The figure below shows the location of PSS and SSS in LTE-TDD and the major difference from LTE FDD is that LTE TDD
embedding the Primary Sync channel in the DwPTS so the location will not be affected by different DL/UL combination
ratio
2.8 Uplink Physical Channel Structure
It is worth mentioning the physical structure of uplink channel. One uplink Slot is as below.

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2.8.1 FDD Uplink Control, Sounding and Demodulation Reference Signal Structure
The figure below shows the relative position of uplink control channels in the frequency domain in relation to the
entire channel bandwidth. In summary,
1) PUCCH resources are located at the edges of the spectrum
To maximize frequency diversity••
2) Multiple UEs can share the same PUCCH resource block
3) PUCCH is never transmitted simultaneously with PUSCH from the same UE
4) Two consecutive PUCCH slots in Time-Frequency Hopping at the slot boundary

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The Figure below shows respective position of the uplink demodulation reference signal in FDD LTE uplink frame
structure including sounding reference signal position.
For LTE TDD only, SRSs can be transmitted in an ordinary sub-frame or in UpPTS sub-frame to improve spectral
efficiency. Normally, it uses UpPTS sub-frame.
2.9 Multiple Input Multiple Output (MIMO)
MIMO and other transmit spatial diversity scheme is a newer application than receive diversity and has become widely
implemented only in the early 2000s. As the signals sent from different transmit antennas interfere with one another,
processing is required at both the transmitter and the receiver in order to achieve gain while removing or at least
attenuating the spatial interference. By using multiple antenna to transmit multiple path of information to UEs, either
better throughput or lower SINR requirement can be achieved and the frequency selective characteristics of LTE is
perfect for the implementation of such technologies. In general there are two mode of MIMO, open and closed loop.
Additionally, if the multiple antennae are already at the base station for uplink receive diversity, the incremental cost of
using them for transmit diversity is very low. Multiple antennae transmit schemes—both transmit diversity and spatial
multiplexing—are often categorized as either open loop or closed loop. A high level signal processing diagram is
shown below.
2.9.1 3GPP MIMO Mode Definition
The table below shows the 8 definition used by 3GPP for MIMO modes

16
2.9.2 Open Loop MIMO
Open-loop systems do not require knowledge of the channel at the transmitter. As a result, open loop operations
occur when the access network does not have information or feedback from the UE to do coding adjustment or signal
is not good enough.
The figure below shows a possible N Antennae + M input layers setup in spatial multiplexing

17
2.9.3 Closed Loop MIMO
On the contrary, closed-loop systems require channel knowledge at the transmitter, thus necessitating either channel
reciprocity—same uplink and downlink channel, possible in TDD—or more commonly a feedback channel from the
receiver to the transmitter. Hence, unlike open loop, closed loop operations occur when the access network execute
dynamic adjustment based on feedback from the UE. The figure below shows a functional view of closed loop MIMO.
As a result, a more accurate coding application can be applied to the communication with the UE. The figure below
shows where the pre-coding function may exist in a N Antennae with M input layers
In mode 5 (Multi-user MIMO), different UEs are receiving downlink data from different antenna. As a result, the overall
throughput per cell is increased.

18
2.9.4 Pre-coding Matrix
3GPP 36-211 defines the types of matrix need to be used when multiple antennae are to be used for different
conditions. The following is a quick summary of some possible pre-coding matrix combination under different
scenarios
I. Spatial Multiplexing Matrix Using Two Antenna Ports with Cell-Specific Reference Signals
Spatial multiplexing is where multiple independent streams are transmitted across multiple antennas. If the receiver
also has multiple antennas, the streams can be separated out using spatial multiplexing. Instead of increasing
diversity, multiple antennas in this case are used to increase the data rate or capacity of the system. In a rich multipath
environment, the capacity of the system can theoretically be increased linearly with the number of antennas when
performing spatial multiplexing.
Even two appropriately spaced antennas appear to be sufficient to eliminate most deep fades, which paints a
promising picture for the potential benefits of spatial diversity. One main advantage of spatial diversity relative to
time and frequency diversity is that no additional bandwidth or power is needed in order to take advantage of spatial
diversity. The cost of each additional antenna, its RF chain, and the associated signal processing required to modulate
or demodulate multiple spatial streams may not be negligible, but this trade-off is often very attractive for a small
number of antennas,
However, unlike transmit diversity and beam-forming, spatial multiplexing works mainly under good SINR conditions.
A 2 × 2 MIMO system doubles the peak throughput capability of LTE but this is unlikely to be possible for all users in
the cell due to variation in SINR.The capacity, or maximum data rate, grows as when the SINR is large. When the SNR
is high, spatial multiplexing is optimal. On the other hand, when the SINR is low, the capacity maximizing strategy is to
send a single stream of data, using diversity pre-coding. Although capacity gain is much smaller than at high SINR, the
capacity still grows approximately linearly with since capacity is linear with SINR in the low-SINR regime.
If the mobile station has only one antenna, LTE can still support spatial multiplexing by coding across multiple users in
the uplink. This is called Multi-User MIMO (MU-MIMO).
The matrix used for two antennae spatial multiplexing is shown below.

19
II. Transmit Diversity Matrix Using Two Antenna Ports
The following matrix applies to input x is and y is the resulting output using a two antenna output configuration.
III. Spatial Multiplexing Matrix Using Four Antenna Ports with Cell-Specific Reference Signals

20
IV. Transmit Diversity Matrix Using Four Antenna Ports
The following matrix applies to input x is and y is the resulting output under a four antenna output configuration.
2.9.5 Beam Forming
Multiple antennas in LTE may also be used to transmit the same signal appropriately weighted for each antenna
element such that the effect is to focus the transmitted beam in the direction of the receiver and away from
interference, thereby improving the received SINR. The beam-forming weight vector should increase the antenna gain
in the direction of the desired user while simultaneously minimizing the gain in the directions of interferers. Beam-
forming can provide significant improvement in the coverage range, capacity, and reliability. To perform transmit beam-
forming, the transmitter needs to have accurate knowledge of the channel, which in the case of TDD is easily available
owing to channel reciprocity but for FDD requires a feedback channel to learn the channel characteristics so it is not
implemented in LTE Release 8 or 9 yet. As of today, beam forming is specific only to LTE TDD and can operate either
under 4x4 or 8x2 configurations.

21
One popular beam-forming algorithm is based on Direction of Arrival where the incoming signals to a receiver may
consist of desired energy and interference energy—for example, from other users or from multipath reflections. The
various signals can be characterized in terms of the DOA or the angle of arrival (AOA) of each received signal. Each
DOA can be estimated by using EUTRAN signal-processing techniques as requested in 3GPP-TS 36-214. From these
acquired DOAs, a beam-former extracts a weighting vector for the antenna elements and uses it to transmit or receive
the desired signal of a specific user while suppressing the undesired interference signals.
Ideally, the beam-former has unity gain for the desired user and two nulls at the directions of two interferers and can
place nulls in the directions of interferers. The DOA-based beam-former in this case is often called the null-steering
beam-former. The null-steering beam-former can be designed to completely cancel out interfering signals only if the
number of such signals is strictly less than the number of antenna elements.
Typically, there exists a trade-off between interference null and desired gain lost. Thus far, we have assumed that the
array response vectors of different users with corresponding AOAs are known. In practice, each resolvable multipath
is likely to comprise several unresolved components coming from significantly different angles. In this case, it is not
possible to associate a discrete AOA with a signal impinging the antenna array. Therefore, the DOA based beam-former
is viable only in LOS environments or in environments with limited local scattering around the transmitter.
2.10 LTE FDD vs LTE TDD Main Features Comparison
The following table summarizes the major similarity between LTE FDD and LTE TDD
The table below summarizes the difference between the two technologies.

22
2.11 LTE Channels Hierarchy Overview
2.11.1 Physical Channel Modulation Schemes
Supported modulation schemes in LTE are: QPSK, 16QAM, 64QAM. Maximum information block size = 6144 bits and
CRC-24 is used for error detection. Broadcast channel only uses QPSK and are shown below.

23
2.11.2 Downlink Channel Functionality Breakdown
2.11.3 Uplink Channel Functionality Breakdown
2.11.4 Channel Functionality Description in Detail
Physical channels
PDSCH: Physical Downlink Shared Channel••
PBCH: Physical broadcast channel••
PMCH: Physical multicast channel••
PDCCH: Physical Downlink Control Channel••
PCFICH: Physical control format indicator channel••
PHICH: Physical Hybrid ARQ Indicator Channel••

24
Reference Signal (RS)
Cell specific RS••
UE-specific RS••
MBSFN RS••
Synchronization Signal (SCH)
Primary Synchronization Signal (P-SCH)••
Secondary Synchronization Signal (S-SCH)••
SCH used for:
Symbol synchronization••
Frame synchronization••
Cell-ID determination••
BCH indicates:
Basic L1/L2 system parameters••
Downlink system bandwidth••
Reference-signal transmit power••
Multi-media Broadcast over a Single Frequency Network (MBSFN)-related parameters••
Number of transmit antennas••
HARQ resource allocation••
Control region is 1-3 OFDM symbols at the beginning of each subframe, composed of control channel elements (CCEs)
4 Res = Resource element group (REG)••
9 REGs = 1 CCE••
PCFICH – Physical Control Format Indicator Channel
# of OFDM symbols of control region••
PHICH – Physical Hybrid ARQ Channel
ACK/NACK signalling••
PDCCH – Physical Downlink Control Channel
Scheduling••
UL power control••
SCH/BCH each occupy 72 center subcarriers regardless of system bandwidth

25
2.11.5 Downlink Control Channel and RE Mapping Relationship
2.12 Cell Search, Synchronization Mobility–UE Call Flow View
2.12.1 Cell Search and Synchronization

26
2.12.2 UE Procedure for Reporting Channel Quality Indication (CQI), Precoding Matrix
Indicator (PMI) and Rank Indication (RI)
As stated in TS 36-213, the time and frequency resources that can be used by the UE to report CQI, PMI, and RI are
controlled by the eNodeB. For spatial multiplexing, the UE shall determine a RI corresponding to the number of useful
transmission layers. For transmit diversity RI is equal to one. A UE in transmission mode 8 is configured with PMI/RI
reporting if the parameter PMI-RI-Report is configured by higher layer signaling; otherwise, it is configured without
PMI/RI reporting.
CQI, PMI, and RI reporting is periodic or a-periodic. A UE shall transmit periodic CQI/PMI, or RI reporting on PUCCH
as defined hereafter in sub-frames with no PUSCH allocation. A UE shall transmit periodic CQI/PMI or RI reporting
on PUSCH as defined hereafter in sub-frames with PUSCH allocation, where the UE shall use the same PUCCH-based
periodic CQI/PMI or RI reporting format on PUSCH. A UE shall transmit a-periodic CQI/PMI, and RI reporting on PUSCH
if the conditions specified hereafter are met. For a-periodic CQI reporting, RI reporting is transmitted only if configured
CQI/PMI/RI feedback type supports RI reporting. Figure below shows which channels will be used for different CQI
reporting scenario

27
2.12.5 EUTRAN Hierarchy and Interface Overview
2.12.4 Mobility Management
2.12.3 System Information Bit Definition

28
2.12.6 Summary of Handover Call Flow – 3GPP Example TS36.300

29
2.13 Example of Peak Data Rate Calculation

30
3 LTE Frequency and Spectrum Planning
3.1 Frequency Spectrum Overview - FDD
3rd Generation Partnership Project (3GPP) Release 8/9 (3GPP TS36.104-860 Table 5.5-1 E-UTRA frequency bands) has
clearly defined LTE as a system that can operate in various frequency bands into order to suit the need of different
operators in the world. The table below shows the actual frequency range listed per the specification for the Frequency
Division Duplex (FDD) version.
The most popular commercial LTE bands are 2.6GHz (Band 7), AWS (Band 4) and 700MHz (Band 12) while momentum
is being built up also for 1800MHz (Band 3) as well as Public Safety spectrum (Band 14)
According to 3GPP TS 36.104 V9.4.0 (2010-06), Band 6 is no longer applicable and Band 15 and Band 16 are listed as
Reserved.
3.2 Frequency Spectrum Overview - TDD
3GPP Release 8/9 (3GPP TS36.104-860 Table 5.5-1 E-UTRA frequency bands) has also defined the operating frequency
for Time Division Duplex (TDD) based LTE technology in various frequency bands in order to operate in different parts
of the world. The table below shows the actual frequency range listed per the specification for the TDD version.
Figure 3-1 LTE FDD Spectrum Allocation

31
It is worth noting that around the 2.3GHz band (Band 40), there is a significant frequency spectrum overlap (100MHz)
between LTE TDD with WiMAX. To many WiMAX operators currently in this frequency band, it is an ideal opportunity
to evolve their network back into the mainstream LTE technologies.
3.3 Channel Bandwidth and Subcarrier Allocation
According to 3GPP specification, Operators can assign different channel bandwidth to suit their particular needs per
the figure below. The number of RB supported for each bandwidth is equal to number of sub-carriers divided by 12.
Figure 3-2 LTE TDD Spectrum Allocation
Figure 3-3 Transmission bandwidth configuration NRB in E-UTRA channel bandwidths
The channel edges are defined as the lowest and highest frequencies of the carrier separated by the channel
bandwidth, i.e. at FC +/- BWChannel /2.

32
Figure 3-4 Definition of Channel Bandwidth and Transmission Bandwidth Configuration for one E-UTRA carrier
Figure 3-5 Visualizing the Relationship between Channel Bandwidth, NRB and Transmission Bandwidth Configuration
3.4 Channel Arrangement
According to 3GPP specification, operators can assign different channel bandwidth to suit their particular needs per
the table below.
3.4.1 Channel Spacing
The spacing between carriers will depend on the deployment scenario, the size of the frequency block available and
the channel bandwidths. The nominal channel spacing between two adjacent E-UTRA carriers is defined as following:
Nominal Channel spacing = (BWChannel(1) + BWChannel(2))/2
where BWChannel(1) and BWChannel(2) are the channel bandwidths of the two respective E-UTRA carriers. The channel
spacing can be adjusted to optimize performance in a particular deployment scenario.
3.4.2 Channel Raster
The channel raster is 100 kHz for all bands, which means that the carrier centre frequency must be an integer multiple of 100 kHz.

33
3.4.3 Carrier Frequency and EARFCN
The carrier frequency in the uplink and downlink is designated by the E-UTRA Absolute Radio Frequency Channel
Number (EARFCN) in the range 0 - 65535. The relation between EARFCN and carrier frequency in MHz for the downlink
is given by the following equation, where FDL_low and NOffs-DL are given in table 5.7.3-1 and NDL is the downlink EARFCN.
FDL = FDL_low + 0.1(NDL – NOffs-DL)
The relation between EARFCN and carrier frequency in MHz for the uplink is given by the following equation where
FUL_low and NOffs-UL are given in table 5.7.3-1 and NUL is the uplink EARFCN.
FUL = FUL_low + 0.1(NUL – NOffs-UL)
NOTE: The channel numbers that designate central carrier frequencies so close to the operating band edges that the
carrier extends beyond the operating band edge shall not be used. This implies that the first 7, 15, 25, 50, 75 and 100
channel numbers at the lower operating band edge and the last 6, 14, 24, 49, 74 and 99 channel numbers at the upper
operating band edge shall not be used for channel bandwidths of 1.4, 3, 5, 10, 15 and 20 MHz respectively because of
the bandwidth requirement. For example, for a 20MHz carrier, using channel 99 as center frequency will extend the LTE
carrier below the allocated spectrum (99*0.1 = 9.9MHz but actual requirement is 10MHz from lower edge)
E-UTRA
Operating
Band
Downlink Uplink
FDL_low [MHz] NOffs-DL Range of NDL FUL_low [MHz] NOffs-UL Range of NUL
1 2110 0 0 - 599 1920 18000 18000 - 18599
2 1930 600 600 - 1199 1850 18600 18600 - 19199
3 1805 1200 1200 - 1949 1710 19200 19200 - 19949
4 2110 1950 1950 - 2399 1710 19950 19950 - 20399
5 869 2400 2400 - 2649 824 20400 20400 - 20649
6 875 2650 2650 - 2749 830 20650 20650 - 20749
7 2620 2750 2750 - 3449 2500 20750 20750 - 21449
8 925 3450 3450 - 3799 880 21450 21450 - 21799
9 1844.9 3800 3800 - 4149 1749.9 21800 21800 - 22149
10 2110 4150 4150 - 4749 1710 22150 22150 - 22749
11 1475.9 4750 4750 - 4949 1427.9 22750 22750 - 22949
12 729 5010 5010 - 5179 699 23010 23010 - 23179
13 746 5180 5180 - 5279 777 23180 23180 - 23279
14 758 5280 5280 - 5379 788 23280 23280 - 23379
…
17 734 5730 5730 - 5849 704 23730 23730 - 23849
18 860 5850 5850 - 5999 815 23850 23850 - 23999
19 875 6000 6000 - 6149 830 24000 24000 - 24149
20 791 6150 6150 - 6449 832 24150 24150 - 24449
21 1495.9 6450 6450 - 6599 1447.9 24450 24450 - 24599
…
33 1900 36000 36000 - 36199 1900 36000 36000 - 36199
34 2010 36200 36200 - 36349 2010 36200 36200 - 36349

34
Figure 3-6 E-UTRA channel numbers – 3GPP 36104-A10 – Table 5.7.3-1
E-UTRA
Operating
Band
Downlink Uplink
FDL_low [MHz] NOffs-DL Range of NDL FUL_low [MHz] NOffs-UL Range of NUL
35 1850 36350 36350 - 36949 1850 36350 36350 - 36949
36 1930 36950 36950 - 37549 1930 36950 36950 - 37549
37 1910 37550 37550 - 37749 1910 37550 37550 - 37749
38 2570 37750 37750 - 38249 2570 37750 37750 - 38249
39 1880 38250 38250 - 38649 1880 38250 38250 - 38649
40 2300 38650 38650 - 39649 2300 38650 38650 - 39649
41 2496 39650 39650 - 41589 2496 39650 39650 - 41589
42 3400 41590 41590 - 43589 3400 41590 41590 - 43589
43 3600 43590 43590 - 45589 3600 43590 43590 - 45589
NOTE: The channel numbers that designate carrier frequencies so close to the operating band edges that the carrier extends
beyond the operating band edge shall not be used. This implies that the first 7, 15, 25, 50, 75 and 100 channel numbers
at the lower operating band edge and the last 6, 14, 24, 49, 74 and 99 channel numbers at the upper operating band
edge shall not be used for channel bandwidths of 1.4, 3, 5, 10, 15 and 20 MHz respectively.
3.5 Frequency Planning Recommendations
3.5.1 Conventional Frequency Reuse Scheme 1*3*1
Under this scheme, a single frequency will be used for the entire system. Although it eliminates the need of any
frequency planning considerations, it also opens the door for inter-site and inter-sector interference which is
detrimental for urban LTE deployment due to the high site density.
Figure 3-7 Conventional 1*3*1 frequency planning scheme
Application scenario
Limited application scenario in urban and suburban environment without impacting QoS/QoE.••
Possible application in highly isolated rural scenario where users are also highly scattered••

35
Advantage
High spectral efficiency and high throughput per site.••
Easy to deploy.••
No special scheduling algorithm required••
Disadvantage
High level of interference especially on cell edge area••
Low throughput on cell boundary and lower QoS/QoE for users on boundary area.••
Coverage control of cells becomes an important factor in achieving a high throughput level••
3.5.2 SFR 1*3*1 – Downlink and Uplink
SFR (Soft Frequency reuse) is the recommended frequency reuse methodology. Both FDD and TDD can use this interference
reduction method. The SFR concept is based on dividing the entire LTE carrier bandwidth into 3 sub-sections as shown below
Under this configuration, each sector will only use one of the sub-sections, also known as the primary band, which “1/3”
of the entire carrier bandwidth, to serve the cell edge users. As a result, the interference level between sectors can be
reduced, thereby enhancing the throughput of those users.
For those users location near the center of the cell, the other 2 sections, which is the remaining “2/3” of the carrier
bandwidth, also known as the secondary band, will be used to serve these users. The figure below depicts the actual layout
Figure 3-8 SFR 1*3*1 Downlink frequency division scheme
Figure 3-9 SFR 1*3*1 Downlink frequency planning scheme

36
Application scenario
Recommended configuration to satisfy high traffic and high site density requirement.••
Best results will require the introduction of Inter Cell Interference Coordination (ICIC)••
Advantage
Reduce inter-cell interference under a high site density deployment.••
Improve cell edge user throughput and quality of experience.••
3.5.3 TDD Specific Frequency Planning Considerations
It is very common for telecom Operators within the TDD band of LTE have a wider unpaired spectrum than the
bandwidth defined maximum carrier bandwidth of 20MHz. As a result, the selection of carrier bandwidth for multiple
carrier condition is also more complex in TDD than FDD. Moreover, the coexistence of WiMAX within the same TDD
spectrum is also very common and this has further complicated the carrier and bandwidth planning for LTE TDD
network from a carrier planning perspective. Planning engineers need to take all these variations along with customer
throughput and coverage requirement into account when it comes to TDD frequency planning.
Besides, carrier bandwidth, co-frequency and time sharing nature between uplink and downlink in TDD also require
careful selection of guard band and pilot time slot (DwPTS, GP and UpPTS). Failure to include enough separation will
create a lot of co-channel interference which will degrade the throughput performance significantly
Figure 3-10 Uplink-Downlink Pilot Time Slot and Guard band Configuration Schemes
Lastly, for TDD to work properly, all cells must be operating in time synchronous mode to avoid any extra interference
being introduced to the network. IEEE 1588v2 implementation is recommended and will help to ensure the integrity of
time synchronization within the LTE TDD network.

37
3.5.4 Frequency Band Selection
As many Operators worldwide possess spectrum in various frequency bands, choosing which band to use for LTE
is always an important consideration. Parameters that will affect the overall cell coverage will be discussed in the
next chapter. However, it is important to remember many components on the radio path will have slightly different
properties at different frequency bands which will modify the final cell coverage radius. For example, antenna gain,
feeder loss, power amplifier output, propagation characteristics, cell edge user throughput and penetration loss are all
dependent on the operating frequency chosen.
Results shown below are typical comparison in coverage radius between different frequency bands. Final results are
highly dependent on the actual parameters used for customer design.
Figure 3-11 Synchronization Solution based on IPclk or 1588v2
Figure 3-12 Cell Coverage Comparison (UL@128kbps) between various frequency bands
Cell Range in Uplink Case -- Result

38
Cell Range in Downlink Case -- Result
Figure 3-13 Cell Coverage Comparison (DL@1024kbps) between various frequency bands
3.5.5 Cyclic Prefix Planning
Although Cyclic Prefix is not directly related to frequency or spectrum allocation, it will impact the actual cell range that
can be served from a logical and signal processing perspective. By carrying a smaller number of symbols (6), a bigger
cyclic prefix is configured per cell to allow a bigger delay in propagation. This is also known as long CP.
The figure below shows the difference in symbol configurations between the normal, 7 symbols configuration (norma
lCP) against 6 symbols (long CP configuration)
Figure 3-14 Cyclic Prefix Comparison
3.5.6 Placing Multiple Technologies@Multiple Frequency Band
Choosing which technologies for which spectrum is a major challenge for many Operators worldwide. It is highly
dependent on what the Operator already owned and what is their future business plan.
Typically, higher frequency bands are likely to deploy more data centric services for high density area (e.g. CBD). As a
result, LTE is more likely the technology of choice for most Operators looking at launching data services in the higher

39
frequency band. The figure below just some 1 example of what customer may do with multiple technologies and their
evolution in different frequency band. It is the responsibility of the radio planner and account managers to work with
customer to determine the best combination to meet their interest.
SingleSON Solution Benefits:
SingleSON brings synergized automation for GSM, UMTS and LTE••
It can remarkably reduce operational cost and improve efficiency, better user experience.••
Dual-band Network Deployment is a trend
Figure 3-15 Example of Multiple Technologies Deployment to Various Frequency Band

40
Figure 4-1 Radio network coverage pre-planning flow
4 Link Budget and Coverage Planning
Operators are rightfully focused on the service quality of a system and coverage is an important part of the service
quality of a system. The aim of radio network planning is to balance coverage, capacity, quality, and cost so none of
these can be considered in isolation.
Various factors must be considered during LTE system coverage planning and setting of these parameters will affect
coverage radius and the quantity of base stations. Coverage and design requirement must be analyzed in choosing
parameters within the following parameter groups:
Propagation-related••
Equipment-related••
LTE-specific••
System Reliability••
Specific Considerations••
Achievable cell radius can be derived from the Excel based link budget tools. Network planning tool, GENEX U-net, will
provide site deployment specific simulation analysis to obtain the number of required base stations in the target area.
The coverage area offered by a 3 sector and Omni site along with coverage planning flow is shown below

41
This chapter will focus on the RF link budget itself and radio transmission model. System simulation will be described in
Chapter7.
4.1 Conventional Link Budget
The purpose of link budget in LTE network planning is:
To use such factors as building penetration loss, feeder loss, antenna gain, and the interference margin of radio••
links to calculate all gains and losses that will affect the final cell coverage
To estimate the maximum link loss allowed based on the maximum transmit power of the terminal and eNodeB••
transmit power allocation.
Coverage radius of a base station can be obtained according to the maximum link loss allowance under a certain
propagation model. The radius can be used in subsequent design.
Link budget parameters are grouped as follows:
Propagation (Transmission) related parameters, such as the penetration loss, body loss, feeder loss, and background••
noise
Equipment dependent parameters, such as the transmit power, receiver sensitivity, and antenna gain••
LTE-specific parameters, such as the pilot power boosting gain, Multiple Input Multiple Output (MIMO) gain, edge••
coverage rate, repeated coding gain, interference margin, and fast fading margin
System reliability parameters, such as slow fading margin••
Specific features that will affect the final path gain••
The figure below shows factors that will affect the link budget calculation process.

42
Figure 4-2 Link budget model – Downlink and Uplink
4.2 Propagation Parameters
Propagation-related parameters have no relationship with technical systems or equipment vendors. Propagation-related
gains or losses are constant, and are related to the environment of radio wave transmission. Such parameters include
the penetration loss, body loss, feeder loss, and background noise. To obtain an objective value when comparing the
link budget information of two equipment vendors, you must set the propagation parameters to be the same values.
4.2.1 Channel Model
Channel models used for LTE are defined in 3GPP TS 36.101 where the test condition was specified. Items covered
include multi-path conditions, fading, and the terminal motion speed of the channel. Common models include speed
at 3km/h, 30km, 60km and 120km. If required, different speed/condition can also be introduced and simulated
according to specific needs.
EPA3 and ETU3 are applicable to fixed services or pedestrian speed services. ETU30, ETU60, ETU120, EVA30, EVA60
and EVA 120 are applicable to vehicular services. Common channel models in LTE systems include EPA (Extended
Pedestrian A), EVA (Extended Vehicular Model A) and ETU3 (Extended Typical Urban Model at 3km/hr).

43
PDP
Extended Pedestrian A
model
Extended Vehicular A
model
Extended Typical Urban
model
# of Paths 7 9 9
Relative
Path Power
(dB)
Delay (ns)
0.0 0 0.0 0 -1.0 0
-1.0 30 -1.5 30 -1.0 50
-2.0 70 -1.4 150 -1.0 120
-3.0 90 -3.6 310 0.0 200
-8.0 110 -0.6 370 0.0 230
-17.2 190 -9.1 710 0.0 500
-20.8 410 -7.0 1090 -3.0 1600
-12.0 1730 -5.0 2300
-16.9 2510 -7.0 5000
Table 4-1 Typical Propagation Channel Models used for LTE
4.2.2 3GPP Value for Multipath and Doppler Effect
Table below shows some of the propagation conditions that are used for performance measurements in multi-path
fading environment at low, medium high Doppler frequencies
Model Maximum Doppler frequency
EPA 5Hz 5 Hz
EVA 5Hz 5 Hz
EVA 70Hz 70 Hz
ETU 70Hz 70 Hz
ETU 300Hz 300 Hz
Excess tap delay [ns] Relative power [dB]
0 0.0
30 -1.0
70 -2.0
90 -3.0
110 -8.0
190 -17.2
410 -20.8
Table below shows possible variation of received power in multi-path fading environment under the various extended
delay spread conditions listed below
Extended Pedestrian A Model - EPA
0 -1.0
50 -1.0
Extended Typical Urban Model – ETU

44
0 0.0
30 -1.5
150 -1.4
310 -3.6
370 -0.6
710 -9.1
1090 -7.0
1730 -12.0
2510 -16.9
Extended Vehicular A Model – EVA
A separate high speed train model is also defined and the Doppler shift trajectory is shown in the diagram below.
120 -1.0
200 0.0
230 0.0
500 0.0
1600 -3.0
2300 -5.0
5000 -7.0
The assumption for this model is where Ds/2 is the initial distance of the train from eNodeB, and Dmin is eNodeB
Railway track distance, both in meters; V is the velocity of the train in m/seconds.

45
4.2.3 Propagation Model
The radio propagation model plays a key role in the link budget. The coverage radius of a base station is obtained
based on the maximum propagation loss allowance in the link budget. Radio propagation models are classified into
outdoor and indoor propagation models. These two types of propagation models involve different factors. In an
outdoor environment, landforms and obstructions on the propagation path, such as buildings and trees, must be
considered. Signals fade at varying rates in different environments. Propagation in free space gives the lowest fade
rate. The fading of signals is larger than free space when radio waves propagate in open areas/suburban areas and
fading rate is the largest in urban/dense urban areas. Indoor propagation model features low RF transmit power, a
short coverage distance and complicated environmental changes.
Although every planning tool will use slightly different method in their propagation calculation, the propagation
models are generally based around modifying the following K factors.
K1-los
Indicate K1 and K2 in the line-of-sight condition.
K2-los
K1-nlos
Indicate K1 and K2 in the none-line-of-sight condition.
K2-nlos
K3 Indicates a coefficient related to Effective height of Transmitter.
K4 Indicates a coefficient related to diffraction loss.
Method
Method of calculating diffraction includes.
0-No Diffraction••
Do not count the diffraction loss.••
1-Deygout••
This diffraction algorithm calculates the diffraction of a maximum of three obstacles.••
2-Epstein-Peterson••
This calculation method is the same as Deygout, except that the method for calculating the height of••
obstacles is different.
3-Deygout with correction••
Correct the distance based on the Deygout calculation method.••
4-Millington••
This diffraction algorithm calculates the diffraction of only one obstacle.••
Other parameters
K5 Indicates a coefficient related to the propagation distance and the effective height of the transmitter.
K6 Indicates a coefficient related to the receiver height.
Kclutter Indicates a coefficient related to clutter loss.
This section describes the common propagation models in LTE planning.

46
I. Free Space Model
Free space indicates an ideal, even, and isotropic medium of space. When electromagnetic waves are transmitted
in this medium, no reflection, refraction, scattering, or absorption occurs. Propagation losses are caused only by the
energy spread of electromagnetic waves. Satellite communication and microwave line-of-sight (LOS) communication
are typical examples of free space propagation. In certain conditions, the antennae of the base station and terminal
can be mounted at any height. In this case, LOS communication between the base station and the terminal is
implemented. If a clear line of sight (CLOS) exists between the transmit antenna and receive antenna, then path loss
complies with the free space model. The propagation losses in the free space model are as follows:
PL = 32.4 + 20log(d ) + 20log( f )
Where, d indicates the distance between the terminal and the base station. The unit is km. f indicates the carrier
frequency. The unit is MHz. The preceding formula does not consider the impact of ground reflection, and thus often
underestimates propagation loss. This model is applicable to the scenario when the antennas of the base station and
terminal are mounted at considerable height and CLOS exists between the base station and the terminal.
II. Cost231-Hata Model
Cost231-Hata model can be used in macro cells as the propagation model. The application range is as follows:
Frequency band: 1500 MHz to 2000 MHz
Base station height: 30 meters to 200 meters. The base station must be higher than the surrounding buildings.
Terminal antenna height: 1 meter to 10 meters
Distance between the transmitter and receiver: 1 km to 20 km
The Cost231-Hata model can be expressed by the following formula:
Total = L - a(Hss) + Cm
L = 46.3 + 33.9 × lg( f ) - 13.82 × lg(HBS) + (44.9 - 6.55 × lg(HBS)) × lg(d )
Where, f indicates the working frequency of the system. The unit is MHz.
HBS indicates the height of the base station antenna. The unit is m.
HSS indicates the height of the terminal antenna. The unit is m.
d indicates the distance between the terminal and the base station. The unit is km.
a(hss) indicates the terminal gain function. This function is related to the antenna height and working frequency of the
terminal and the environment.
The value of Cm depends on the terrain type. The values of Cm in the standard Cost231-Hata are as follows:
In large cities: Cm = 3 (as defined in Urban - large city in the related protocol)

47
In medium-sized cities: Cm = 0 (as defined in Urban – small city in the related protocol)
In suburban areas: Cm = -2(log( f /28))2
- 5.4dB (as defined in Urban – Suburban in the related protocol)
In rural open areas: Cm = -4.78 × (lg( f ))2
+ 18.33 × lg( f ) -40.94
(As defined in Rural (open) – desert in the related protocol)
In highways: Cm = -4.78 × (lg( f ))2
+ 18.33 × lg( f ) -35.94
(As defined in Rural (quasi-open) – countryside where the terminal is unobstructed for 100 meters in the front in the
related protocol)
Since some of the working frequencies of the LTE networks are 2.3 GHz and 2.6 GHz have exceeded the band range
of the standard Cost 231-Hata model, that is, 150 MHz to 2000 MHz. Therefore, in the actual LTE system design, the
standard Cost231-Hata model must be corrected based on the CW test result. According to the planning experience
and actual CW test results in multiple scenarios, a set of Cm has been created in the experienced model.
III. Standard Propagation Model (SPM)
The standard propagation model is a model (deduced from the Hata formula) particularly suitable for predication
in the 150MHz~3500MHz band over long distance (1Kmd20Km) and is very adapted to GSM900/1800, UMTS,
CDMA2000, WiMAX and LTE technologies. This model uses the terrain profile, diffraction mechanisms (calculated in
several ways) and take into account clutter classes and effective antenna heights in order to calculate path loss.
The model may be used for any technology; it is based on the following formula:
LSPM = K1 + K2 log (d )+ K3 log (H Txeff)+ K4 Diffractio nLoss + K5 log (d )log (H Txeff)+ K6 H Rxeff + K cluttrt f (clutter)
Where:
K1 Constant offset (dB)
K2 Multiplying factor for log(d)
d Distance between the receiver and the transmitter (m)
K3 Multiplying factor for log(HTxeff)
HTxeff Effective height of the transmitter antenna(m)
K4 Multiplying factor for diffraction calculation, K4 has to be a positive number
Diffraction loss Losses due to diffraction over an obstructed path(dB)
K5 Multiplying factor for log(d)log(HTxeff)
K6 Multiplying factor for HRxeff
HRxeff Mobile antenna height (m)
KClutter Multiplying factor for f(clutter)
f(clutter) Average of weighted losses due to clutter
The standard propagation model can be used for propagation model calibration through CW (Continuous Wave) test
by using simulation tools- GENEX U-Net.

48
IV. Okumura-Hata Model
The Hata Model for Urban Areas, also known as the Okumura-Hata model for being a developed version of the
Okumura Model, is the most widely used radio frequency propagation model for predicting the behavior of cellular
propagation in built up areas. This model incorporates the graphical information from Okumura model and develops
it further to realize the effects of diffraction, reflection and scattering caused by city structures. Okumura model was
originally built into three modes, one for urban, suburban and open areas. The model for urban areas was built first
and used as the base for others The Okumura Hata model also has two more varieties for propagation in Suburban
Areas and Open Areas. The original Okumura model for Urban Areas is a radio propagation model that was built using
the data collected in the city of Tokyo, Japan. The model is ideal for using in cities with many urban structures but not
many tall blocking structures. The model served as a base for the Hata Model and the following assumptions apply to
the use of Okumura Hata model.
Frequency: 150 MHz to 1500 MHz
Mobile Station Antenna Height: between 1 m and 10 m
Base station Antenna Height: between 30 m and 200 m
Link distance: between 1 km and 20 km.
The traditional Okumura Hata model formula is shown below:
V. ITU Indoor Model
The IEEE documents provide a propagation loss model in the indoor base station environment. This model is based on
the Cost231 model. The expression of this model is as follows:
Where,

49
LFS indicates the propagation losses in free space.
Lc indicates the constant loss.
kwi indicates the number of walls in type i penetration.
n indicates the number of penetrated floors.
Lwi indicates the loss brought by penetration through walls in i mode.
Lf indicates the loss of neighboring floors.
b indicates the experience parameter.
The value of Lc is often 37 dB. In normal indoor offices, the value of n is 4. For capacity calculations in moderately
pessimistic environments, the value can be changed to 3.
Table 4-2 Weighted average for loss categories
Loss category Description Factor (dB)
Lf
Typical floor structures (i.e. offices)
Hollow pot tiles••
Reinforced concrete••
Thickness typ. 30 cm••
18.3
Lw1
Light internal walls
Plasterboard••
Walls with large numbers of holes (e.g. windows)••
3.4
Lw2
Internal walls
Concrete, brick••
Minimum number of holes••
6.9
Caution:
In an indoor cell, often the antenna height of the base station or terminal is not specified and the deviation of shadow
fading in log-normal distribution is often 12 dB.
VI. Ray Tracing Model
The ray tracing model involves analyzing electric wave propagation by using the ray tracing method and obtaining the
field strength of received signals through theoretical calculation. Some LTE network uses the higher part of the UHF
band such as 2.3 GHz and 2.6 GHz. The wavelength of the radio wave is several centimeters. Therefore, obstructions
in the propagation environment are often larger than the wavelength of the radio wave. In this case, the ray tracing
method can be used to analyze wave propagation. In addition, geological information technologies allow you to
identify each building in a city as a right prism in a high precision degree. Such a right prism is identified by the top
coordinate of the polygon at the bottom and height. The basic idea of the ray tracing method is as follows: Determine
the position of a transmission source. Identify all the propagation routes from the transmission source to each receive
point, that is, the test point, according to the features and layout of the buildings on the 3D map. Determine reflection
and diffraction losses based on the Fresnel equation and the geometrical or uniform theory of diffraction. In this case,

50
the field strength of each route to each test point can be obtained. Perform the same point coherence stacking of field
strengths of all routes to obtain the total received field strength of each test point.
The ray tracing model is integrated in common commercial planning software. Simulation software GENEX U-Net uses
a 3D ray tracing model. This model, however, requires highly precise (at least to within 5 meters) digital maps that
contain 3D building information. The prediction accuracy of the model is closely related to the precision of the digital
maps and accuracy of site engineering parameters, such as the antenna position, height, direction angle, and down-tilt
angle. Due to the cost, the ray tracing model is used only in network planning in densely populated areas of large cities.
4.2.4 Penetration Loss
Penetration loss indicates the fading of radio signals from an indoor terminal to a base station due to obstruction by a
building. For an indoor receiver to maintain normal communications, the signal must be sufficiently strong. The indoor
receiver obtains radio signals in the following scenarios:
The indoor receiver obtains signals from an outdoor transmitter.••
The transmitter and receiver are located in a same building. See Figure below••
The link budget is only concerned with the scenario in which an outdoor transmitter is used and the signals penetrate
only one wall.
The propagation modes of electromagnetic waves are as follows: direct radiation, inverse radiation, diffraction,
penetration, and scattering. In areas where no indoor distributed system is deployed, electromagnetic wave signals
are obtained through diffraction and scattering. Therefore, the indoor penetration loss is related to the incident angle,
building materials, terrain, and working frequency. Table below lists the penetration losses associated with typical
buildings.
Figure 4-3 Indoor propagation scenario
Table 4-3 Typical building penetration losses
Typical Penetration Loss (dB)
Frequency (GHz) Concrete Wall Brick Wall Wooden Floor Thick Glass Wall Thin Glass Wall Lift Door
1.8~2.6 15~30 10 5 3~5 1~3 20-30

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