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www.DigiTrainee.com Company Confidential
LTE RF Planning & Optimization Procedure
Section-1
www.DigiTrainee.com Company Confidential
Contents LTE Planning
Charter 1 LTE Network Planning
----- Frequency Planning
----- Coverage Planning
----- Capacity Planning
Charter 2 LTE RNP Solutions
Page 2
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Frequency Reuse 1*3*1
Page 3
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SFR (Soft Frequency Reuse)1*3*1
Page 4
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SFR 1*3*1 Vs FFR 1*3*1
Page 5
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Frequency reuse mode 1*3*3
Page 6
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Charter 1 LTE Network Planning
----- Frequency Planning
----- Coverage Planning
----- Capacity Planning
Charter 2 LTE RNP Solutions
Page 7
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Link Budget Procedure
Page 8
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Link Budget Model: Uplink
Page 9
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Link Budget Model: Downlink
Page 10
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Link Budget Principle
Page 11
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MAPL Calculation Process
Page 12
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Coverage Planning Comparison LTE/CDMA /WiMAX
Page 13
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Charter 2 LTE Network Planning
----- Frequency Planning
----- Coverage Planning
----- Capacity Planning
Charter 3 LTE RNP Solutions
Page 14
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Capacity Analysis Concept
Page 15
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Capacity Estimation Realization Process
Page 16
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Key performance baseline
Page 17
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LTE TA Planning
Page 18
TA: Similar to the location area and routing area in 2G/3G networks, the tracking area (TA) is used for paging. TA planning aims to reduce location update signaling caused by
location changes in the LTE system.
TA list : A list of TAIs that identify the tracking areas that the UE can enter without performing a tracking area updating procedure. The TAIs in a TAI list assigned by an MME to a
UE pertain to the same MME area. In LTE system, if an UE changes the TAs in the TAI list, TA update wont be triggered.
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Network Scenario 1 Los Angeles
Page 19
In the Los Angles, there are several independent density area that connected by
the main road (like island) . The UE may go across the different area through
this road.
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TA Planning Solution
Page 20
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Network Scenario 2 London
Page 21
In this scenario, users are average
distributed in each area
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TA Planning Solution
Page 22
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Rules TA Planning
Page 23
-A TA coverage should be proper setting according to the capability of
EPC
-When the suburban area and urban area are covered discontinuously, an
independent TA is used for the suburban area.
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Rules TA Planning (contd)
Page 24
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Neighbor Cell Planning
Page 25
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ANR & Neighbor Cell Planning
Page 26
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PCI Planning
Page 27
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Scrambling Overview
Page 28
PCI: Physical Cell ID, is used to generate
scrambling code to identify the different cell
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Scrambling Overview (Contd)
Page 29
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PCI Planning Principle
Page 30
Differences between a scrambling code and a PCI: The scrambling code ranges from 0 to 511 whereas the PCI ranges from 0 to
503. In addition, the protocols do not have specific requirements for scrambling code planning. Therefore, only the reuse distance
needs to be ensured in scrambling code planning. For PCI planning, however, 3GPP protocols require that the value of PCI/3
should be 0, 1, or 2 in each eNB.
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Reference Signal in LTE
Page 31
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Reference Signal in LTE
Page 32
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Example of cross antenna interference
Page 33
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Reference Signal in LTE
Page 34
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PCI Planning Modulo 3
Page 35
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Cyclic Prefix Size Decision
Page 36
A CP is a copy of the end of an OFDM symbol to the start position of the
symbol. Each CP generates a guard interval between two OFDM symbols.
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Cyclic Prefix Size Decision (contd)
Page 37
A CP is a copy of the end of an OFDM symbol to the start position of the
symbol. Each CP generates a guard interval between two OFDM symbols.
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Cyclic Prefix Size Decision (contd)
Page 38
The symbol energy that can be captured by the OFDM receiver depends on the CP length:
If the CP is longer than the multipath delay of an OFDM symbol, the OFDM receiver can capture all energy of the
symbol.
If the CP is shorter than the multipath delay of an OFDM symbol, the OFDM receiver can capture only some
energy of the symbol.
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Random Access Preamble Format Decision
Page 39
The random access procedure is used in various scenarios, including initial access, handover, or
re-establishment. Like other 3GPP systems the random access procedure provides a method for
contention and non-contention based access. The PRACH (Physical Random Access Channel)
includes RA (Random Access) preambles generated from ZC (Zadoff-Chu) sequences.
There are five preamble formats defined which four of them are for FDD
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Random Access Preamble Format Decision (Contd)
Page 40
Other preamble formats then Format 0 and Format 4 (TDD) are available only with the LOFD-001009
Extended Cell Access Radius feature.
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U2000 Parameter
Page 41
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Preamble Format & PRACH Configuration Index
Page 42
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Config Index
Page 43
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Root Sequence Index Planning
Page 44
* in fact, with the lowest configuration,
where we assume maximum cell radius of
790m we assign only one value per cell.
Further explanation on following slides.
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PRACH Parameters
Page 45
PRACH configuration is defined by the following parameters
Root sequence, setting in the eNodeB
Ncs: Automatically setting based on the cell radius configuration
PRACHfrequency offset: Scheduled by eNodeB
High speed flag: Indicate whether the cell is for high speed
All the parameters all carried by SIB Type 2
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NCS Selection
Page 46
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Calculation Max Cell Radius for given Ncs
Page 47
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Table Calculation
Page 48
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Ncs Selection Example
Page 49
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Addition TD-LTE Planning
Page 50
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Addition TD-LTE Planning (Contd)
Page 51
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Contents LTE Optimization
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RF Optimization in Site Rollout Flowchart
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LTE RF Optimization Objects
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RSRP (Referense Signal Received Power) and SINR (Signal to Interference plus Noise Ratio)
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RF Optimization recommend baseline
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RF Optimization Methods
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RF Optimization Flowchart
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Contents
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Technical Knowledge and Tool Preparation
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Pre-condition and start for RF Optimization
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Preparations for RF Optimization
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Contents
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Classification of Coverage Problems (RSRP)
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Factors Affecting Coverage
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Resolving Weak Coverage
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Case : Find Weak Coverage Area by Scanner or Drive Tests
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Lack of a Dominant Cell
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Lack of a Dominant Cell
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Resolving Prblems with Lack of a Dominant Cell
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Case : An Area Without a Dominant Cell
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Cross Coverage
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Resolving Cross Coverage Problems
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Case : Cross Coverage Caused by Improper Tilt Settings
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Case-Reverse Connection of The Antenna
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Contents
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Signal Quality (SINR is mainly involved)
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Resolving Signal Quality Problems Caused by Improper Parameter Settings
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Case : Adjusting Antenna Azimuths and Tilts to Reduce Interference
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Case : Changing PCIs of Intra-frequency Cells to Reduce Interference
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Case : Handover Failure Caused by Severe Interference
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Drive Test Route & Justification
Page 82
Each blocking access should be proven by
photo and match with actual condition
(Google Street View)
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Baseline Drive Test
Page 83
RSRP
SINR
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Bad Spot Analysist (Weak Coverage)
Page 84
In this bad spot we will re-orientation from site which have LOS condition much better
from Cluster Condet 1 (Site Jalan Pancoran)
Not Yet ON AIR
Hotel High Building
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Bad Spot Analyst Contd
Page 85
Not Yet ON AIR
Hotel High Building
Jalan Pancoran Mc-P-GF (TA)
Sect1 (10 Deg to 330
Deg) and Uptilt (-2
M.Tilt)
Sect3 (240 Deg to
230 Deg)
In this bad spot we will re-orientation from site which have LOS condition much better
from Cluster Condet 1 (Site Jalan Pancoran)
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Bad Spot Check Result
Page 86
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Bad Spot Analysist (Cross Coverage)
There is overshoot from site Soepomo Dalam need to adjut
M.Tilt
More LOS
Menteng Dalam M-S-GF
Soepomo Dalam Mc-S-GF
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Soepomo Dalam Mc-S-GF (TA)
Sect1 (+3 M.Tilt)M.Tilt (+3/+6/+4)
Menteng Dalam M-S-GF (TA)
Bad Spot Analysist (Cross Coverage)
After Reducing Coverage of Soepomo Dalam
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Bad Spot Analysis (Too Dominant PCI)
Page 89
In order to reduce too many dominant PCI across Kota Dalam Sect1 Main Lobe, Site
Tebet Selatan Sect1 will be change direction to Tebet 4
F2
F2
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Bad Spot TA Analysis (Too Dominant PCI)
Page 90
Kota Dalam Mc-F-GF
Azimuth (340/90/NA)
E.Tilt (+2/+3/NA)Sect3 (220 Degree)
And M.Tilt (-3 Degree)
Tebet Selatan Mc-M-RT
Azimuth (NA/110/230)
M.Tilt (+2/+4/+2)
Abdullah Syafei M-T-RT
M.Tilt (NA/+3/+6)
Asem Baris Mc-P-GF
Tebet 2D Mc-T-GF
Azimuth (340/90/NA)
E.Tilt (+2/+3/NA)
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Bad Spot Check Result
Page 91
F2
F2
Before After
In order to solve one badspot due to too many dominant PCI, required to re-plan new
azimuth and proper tilt configuration and make one PCI more dominant than before.
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Cross Feeder Analysist
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Overview of X-Feeder Troubleshoot
Page 93
For LTE Network SON Feature (PCI Optimization), everyday PCI will be changing. So
during drivetest if not following daily Engineering Parameter from system. Common
people will see there is cross feeder issue. Actually on PCI Optimizer there is no exact
rule lower number of PCI should be correlated with lower number of Local Cell ID.
The general rule of PCI Optimizer one LTE Site should use same SSS ID, and PSS ID
can be randomly as long the system can arrange not facing with the same PSS ID from
the other site.
Whatever the PCI on the implementation, we should be able to analyze the cell
footprint from LTE Broadcast Channel on SIB Type 1. Which contains PLMN ID,
TAC, eNB ID and the Important thing is Cell ID. Cell ID should following rule
clockwise numbering, from the smaller to the higher.
How to breakdown CellIdentity into Cell ID:
= (28. _) + _
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Sector 1
Page 94
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Sector 2
Page 95
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Sector 3
Page 96
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Mapping Problem & Troubleshoot
After we understand above description, left picture showing actual
condition of Cell ID placement, and we can assign related team to swap
CPRI/Feeder according to condition of cross feeder issue exist.
Page 97
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Contents
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Handover issue with coverage
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Handover Problem Analysis
Page 100
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Case: Service Drops Caused by MissingNeighboring Cell Configuration
Page 101
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Summary
Page 102
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End of Section
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