This document provides technical training on optimizing LTE downlink throughput. It discusses:
1. The increasing commercial adoption of LTE networks and rapid growth of LTE users.
2. Challenges in optimizing LTE networks including insufficient analysis capabilities and experience-based adjustments.
3. A proposed optimization scheme involving in-depth analysis of issues like weak coverage, interference and throughput problems to identify root causes and targeted optimization suggestions.
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LTE Large-Scale Commercial Application, Fast Network Construction
2 16
46
148
263 274
0
50
100
150
200
250
300
2009 2010 2011 2012 2013 2014.2
According to GSA, the number of TD-LTE UE types has increased to
304 by January 30, 2014, among which 63 were smart UEs,
exceeding 20% of the total number. The LTE TDD UE industry chain
is mature.
The number of commercial LTE networks has reached 274 (28 LTE
TDD networks) by February 17, 2014
UE Quantity 5 million 10 million 100 million
2G
2 years
(1992–1994)
3 years
(1992–1995)
6 years
(1992–1998)
3G
2 years
(2001–2003)
3 years
(2001–2004)
6 years
(2001–2006)
4G
1.8 years
(Jan 2010–Oct 2011)
2 years
(Jan 2010–Jan 2012)
3.3 years
(Jan 2010–Apr 2013)
The number of LTE users exceed 100 million in 3.3 years, doubling
the growth rate of 2G or 3G UEs.
The commercial application of LTE networks speeds up; the terminal industrial chain matures in
2014; and the number of UEs increased dramatically.
Increasing rapidly
since 2012
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Insufficient LTE Network Optimization Capability
Cell
Name
Value on
the Live
Network
Baseline
Value
Optimization
Suggestion
Cell A X1 Y1 X1–Y1
Cell B X1 Y1 X2–Y1
Cell C X2 Y1 X2–Y1
Issue 3: Poor batch delivery and high labor cost due to the current
optimization platform which provides only process data for
analysis, but no clear analysis results and closure actions.
Issue 4: High network risk and O&M cost due to experience-based
adjustment or uniform optimization using baseline values
Issue 2: Optimization bottlenecks caused by limited optimization
methods due to insufficient in-depth analysis capability
of RF problems in LTE networks
Bottleneck!
Building
new sites
Neighboring
cell
Capacity
expansion
Suggestions
not
differentiated
Increase the
value as an
attempt. If
KPIs
deteriorate,
decrease the
value again.
SmartRNO:
1. Supporting neighboring cell planning
checks (topology analysis only)
FMA:
1. Supporting NE fault analysis and top
cell filtering
2. Cannot provide optimization
suggestions
FMA
Issue 1: As an end-to-end network KPI, LTE throughput may
fluctuate due to various factors.
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Optimization Scheme
Perform end-to-end analysis and
associate the impact of various
network nodes on LTE throughput
Select top cell groups based on
customer concerns and focus on
top sites
Perform in-depth analysis to
identify air interface root causes
and problematic scenarios
Optimization suggestion for
different root causes
Low spectral
efficiency
Low throughput Poor user experience
MME
Transmission
RF SP
TCP/IP
Problem isolation &
demarcation
Root cause identification
Optimization
Missing neighboring cells
Delayed handovers
Uplink/downlink
imbalance
PCI conflicts
PCI confusion
Pilot pollution
Overshoot island coverage
Azimuth exceptions
Network interference
due to coverage overlap
Key parameter adjustment PCI adjustment Channel check ACP antenna adjustment
MRF
MRF, alarms, and CHR
CHR, MRs, engineering
parameters, and configurations
Identification of
problematic cells
RF root
causes
Deeper weak coverage No primary serving cells
The blue blocks invoke other topics.
KPIs evaluation and Identification
of problematic cells
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Top Cell Identification
Select top N (configurable) cells that have the worst performance indicated by the specified KPIs
Cell KPIs such as throughput, channel quality, MCS level, rank 2 ratio, and BLER are displayed.
Use the total duration of downlink data transmission in a cell to calculate a more accurate average cell throughput in the downlink.
Calculate the downlink bearer throughput per UE according to 3GPP specifications and exclude the traffic in the last TTI to obtain a more
accurate result.
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End-to-End Problem Isolation by Segment
UE Root Cause
1. UE capability
2. QCI
configurations
3. AMBR rate
1. Hardware
performance
2. MME
configurations
Air interface Root Cause
Air interface channels:
1. Air interface encoding
(MCS/MIMO/IBLER)
2. Air interface resources
(Grant/RB)
3. Weak
coverage/interference
1. Incorrect parameter
settings
2. Limited traffic capacity
3. Poor coverage
4. Interference
5. Handover exceptions
eNodeB Root Cause
1. eNodeB rate
restriction
2. eNodeB processing
capability
3. Algorithm feature
restrictions
1. Incorrect parameter
settings
2. Incorrect projects
3. eNodeB exceptions
4. Version quality
problems
Non-Air Interface
Factors
Root Cause
Bearer network
transmission channels:
1. Bandwidth restriction
2. Long delay and jitter
3. Packet loss and
disorder
1. Incorrect
parameter settings
2. Limited capacity
or capability
3. Transmission
quality problems
CN Root Cause
1. Registration
configurations
2. Rate
restriction
3. Packet
disorder
1. Incorrect
parameter settings
2. Device faults
3. Version quality
problems
Public Network Root Cause
1. NEs with flow
control
2. Public network
bandwidth
restrictions
1. Incorrect TCP
parameter settings
2. Capacity
restrictions
SP Root Cause
1. Server
capability
2. TCP parameter
settings
3. Software
configurations
1. Hardware
performance
2. Incorrect
parameter
settings
Uu
1
Note: Problems related to public networks and SP servers cannot be analyzed currently.
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Problem Type Root Cause Analysis and Troubleshooting Method Automatic Analysis Applicable Remarks
SP server
Server capability
If possible, connect the test PC directly to the SP server to test low throughput cells
where a certain service is used by a large number of UEs or the download speed of a
certain website is slow.
No
Information about SP servers in commercial use cannot be obtained. Such tests can be
performed only on FTP servers or servers for China Mobile-owned services.
TCP parameters Check the TCP window size. No None
Software configurations Enable the firewall. SP servers do not support TCP port extension. No None
Public network
NEs with flow control Check DPI nodes. The GGSN communicates with the OCS at a too high frequency. No None
Public bandwidth limitation None No None
Core network
Registration configurations Analyze MME CHR data. No, but technically feasible. MMEs must have MV capability for analysis if they are provided by other vendors.
Rate limitation Analyze MME CHR data. No, but technically feasible. None
Packet disorder Analyze MME CHR data. No, but technically feasible. None
Insufficient equipment
capacity
Check the CN equipment capacity usage.
No. The capacity depends on
traffic statistics on the core network.
Check whether such counters as static resource usage, signaling processing resource
usage, forwarding resource usage (SAU/PDP), forwarding bandwidth usage (Mbit/s or
pps), comprehensive resource usage, and average CPU usage are available on the CN
side.
Incorrect parameter
settings
Set core network parameters.
No. The capacity depends on MML
commands on the core network.
None
Software defects This problem only occurs in the area covered by equipment provided by a sole vender. No None
Equipment incompatibility This problem only occurs in the area covered by equipment provided by a sole vender. No None
Transmission
Bandwidth limitation Analyze IPPM and GTPU counters. Yes
Prerequisites of performing such analyses:
1. IPPM counters must be available.
2. The core network equipment in use must be provided by Huawei.
Long delay and large jitter Analyze IPPM and GTPU counters. Yes
Prerequisites of performing such analyses:
1. IPPM counters must be available.
2. The core network equipment in use must be provided by Huawei.
Packet loss and disorder Analyze IPPM and GTPU counters. Yes
Prerequisites of performing such analyses:
1. IPPM counters must be available.
2. The core network equipment in use must be provided by Huawei.
Too many eNodeBs in the
same access ring
Check the bandwidth usage of the eNodeB access ring. (This counter is unavailable
on the wireless network side.)
No
Check whether there are multiple eNodeBs in the same access ring by querying the XML
files of the eNodeB. You can perform the check manually, because automatic analyses
may be inaccurate due to inaccurate data sources.
Bandwidths occupied by
services on the access ring
Check the bandwidth usage of the eNodeB access ring. (This counter is unavailable
on the wireless network side.)
No This is a counter on the transmission side, which may be unavailable.
Incorrect UGW
configurations
Check the quintet configuration and related feature switches. Packets are lost due to
high instant rate of the UGW output port.
No Information about UGW configurations is needed for such analysis.
Root Cause Tree of LTE Throughput Problems
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Problem
Type
Root Cause Analysis and Troubleshooting Method
Automatic
Analysis
Applicable
Remarks
NE
eNodeBs fail or their capability
degrades
Analyze relevant alarms. Yes
The alarm list was complete and consistent with that of X Solutions for PS
Data Transmission Optimization in the LTE Network.
eNodeB rate restriction Check the licensed traffic volume. Yes This method is not verified.
eNodeB processing capability
Analyze traffic statistics (Check whether the CPU usage is
excessive).
Yes
The analysis results of the CPU usage counter were consistent with that of X
Solutions for PS Data Transmission Optimization in the LTE Network.
Algorithm and feature restrictions
Check known problems. Check whether features have any gain.
Check the strategies for enabling features.
Yes
Part of the analysis results were verified. (Analysis results of MLB were
verified in Hangzhou.)
eNodeB capacity restricted Check the usages of CCE, SRS, PUCCH, and PRB resources. Yes
The analysis results of these usage counters were consistent with that of X
Solutions for PS Data Transmission Optimization in the LTE Network.
Antenna
Antenna faults and alarms Analyze relevant alarms. Yes None
Reverse connection or connection
with crossed pairs for antennas
Another document is dedicated to this problem.
Invoke the
corresponding
document.
None
Uplink interference Another document is dedicated to this problem. Yes The analysis results are accurate, which have been verified in Hangzhou.
Imbalanced channels
Check whether there is path loss imbalance of dual-channel
components in indoor distributed eNodeBs with two antennas.
No None
Air
interface
Air interface resources (Grant/RB) Analyze traffic statistics. Yes None
Weak coverage Analyze the measurement report. Yes The MR analysis results are accurate, which have been verified in Hangzhou.
Interference Analyze the measurement report. Yes The MR analysis results are accurate, which have been verified in Hangzhou.
UE
UE capability Analyze CHR signaling. Yes The analysis results are accurate, which have been verified in Hangzhou.
QCI configurations Analyze CHR signaling. Yes The analysis results are accurate, which have been verified in Hangzhou.
AMBR rate Analyze CHR signaling. Yes The analysis results are accurate, which have been verified in Hangzhou.
UE main and diversity reception
imbalance
Perform UE trace test, because a background analysis is not
available.
No
Data sources for such analysis are unavailable and the analysis results
cannot be verified.
Root Cause Tree of LTE Throughput Problems
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End-to-End Problem Isolation by Segment
Perform comprehensive checks on factors affecting LTE throughput to
reduce missing detections
Comprehensive analysis on transmission, hardware, antennas, UEs,
and capacity
Automatic problem identification, highlight of problematic items
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Weak coverage scenarios:
Missing configurations of neighboring cells/delayed
handovers/island coverage/no primary servicing cells/link
imbalance/weak intensive coverage
Identification of
weak coverage
root causes
Delayed
handovers
No primary
serving
cells
Link
imbalance
Weak
intensive
coverage
Island
coverage
Missing
configurations
of neighboring
cells
Serving cell Target cell
UE
Low RSRP of the serving cell and high RSRP of the target cell.
Unconfigured neighbor relationships: If the distance between the UE
and the serving eNodeB is smaller than the average inter-site
distance, the root cause of low throughput is missing configuration of
neighboring cells.
If the distance between the UE and the serving cell is greater than the
average inter-site distance, the root cause of low throughput is island
coverage.
If neighbor relationships are configured and the root cause of low
throughput is delayed handover, adjust handover parameters based
on the signal level difference between the neighboring cell and the
serving cell.
Weak Coverage Root Cause Location
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At the coverage border of multiple neighboring cells that have small
difference in the signal level, there is no primary serving cells with strong
signals, increasing the probability of ping-pong handovers.
Serving cell
Neighboring cell 1
UE
Neighboring cell 2
-102 dBm
-101 dBm
-104 dBm
Weak Coverage Root Cause Location
Serving cell
UE
Due to link reciprocity in LTE TDD networks, path loss imbalance occurs
between the uplink and downlink. As a result, downlink signals may be too
weak for UEs far from eNodeBs to receive, causing link exceptions. This root
cause does not lead to problems to LTE FDD cells.
Serving cell UE
UEs close to the serving eNodeB are in weak coverage areas. This
phenomenon is called coverage hole. This occurs because of a coverage
hole, mostly in indoor scenarios close to eNodeBs
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Interference scenarios:
overshoot coverage/PCI mod 3 conflicts/pilot
pollution/azimuth exceptions
Identification
of air interface
root causes
Pilot
pollution
Overshoot
coverage
PCI mod 3
conflicts
Azimuth
exceptions
UE
Serving cell
Neighboring cell 1
Neighboring cell 2
The RSRP of the serving cell is high, but the channel quality is low.
If the serving cell has an intra-frequency neighboring cell with a similar
RSRP value, intra-frequency interference has a large impact on the
throughput. If PCI mod 3 conflicts occur, the SINR deteriorates.
If the serving cell has no intra-frequency neighboring cells or its
neighboring cells have low RSRP, inter-RAT interference may occur,
such as intermodulation interference of GSM 1800 band to band F and
outband interference from PAS.
Interference Root Cause Location
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Interference Root Cause Location
If PCI mod 3 conflicts occur between the serving cell and neighboring cells and
the reception level of the serving cell is lower than 6 dB, interference occurs in
pilot channels. As a result, the SINR on the RS channel deteriorates, and intra-
frequency PCI mod 3 conflicts occur, affecting the throughput.
Serving cell Neighboring cell
UE
PCI: 0
PCI: 6
-80 dBm -84 dBm
Interference due to azimuth exceptions occurs if the following conditions are met at the
same time:
• Relative locations between the serving cell and neighboring cells do not cause
overlapping coverage.
• UEs receive signals from the neighboring cells.
• PCI mod 3 conflicts occur.
• The reception level of the serving cell is lower than 6 dB.
Method of checking the azimuths of cells (relative locations between cells)
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Interference cell
Serving cell
Neighboring cell
UE
PCI: 0
PCI: 6
-80 dBm
-84 dBm
Overshoot coverage of interference cells occurs when signals
from a remote cell passing through neighboring cells in between
cause interfere to the serving cell.
If PCI mod 3 conflicts do not occur in multiple cells but
the RSRP of these cells are close, there is a probability
that carriers for data service transmission collide with
the RS channel, causing interference to the carriers. As
a result, the SINR deteriorates, and the throughput of
the serving cell decreases, causing pilot pollution.
Interference Root Cause Location
UE
Serving cell Neighboring cell 1
Neighboring cell 2
-80 dBm
-82 dBm
-83 dBm
PCI: 0
PCI: 2
PCI: 1
Interference
cell
Serving cell
Neighboring cell
UE
PCI: 0
PCI: 6
-90 dBm
-91 dBm
Overshoot coverage of the serving cell occurs when signals from
the serving cell passing through neighboring cells in between
cause overlapping coverage with a remote cell.
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Accurate Location of Un Interface Problems
Calculate the number of RF root causes by cell and obtain the distribution of weak coverage and interference root cause percentages
Cause classification of interference problems
Cause classification of weak coverage problems
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Root Cause-based Optimization Suggestions
Provide targeted optimization
methods for different problems to
ensure optimization effect.
Perform intensive parameter
management to lower the
maintenance cost and ensure
healthy network operation.
Perform regular check on
parameters and neighboring cells to
detect minor and potential problems,
ensuring optimal network
configurations.
Perform quantitative analyses on RF
problems and accurately measure
the percentage of weak coverage
and interface root causes to resolve
problems.
Accurate optimization
on neighboring cell
configurations
Missing
configurations of
neighboring cells
Island coverage
Accurate
optimization on
handover parameters
Delayed
handovers
No primary
serving cells
Accurate
optimization on
feature parameters
Link imbalance
Quantitative
optimization on
antenna parameters
Overshoot
coverage
Weak intensive
coverage
Pilot pollution
PCI optimization
PCI mod 3
conflicts
Azimuth
exceptions
1. Find the exact missing
neighbor relationships,
instead of performing
topology-based search
2. Quantize handover
parameters (CIO)
1. Identify incorrect handover
parameter settings based on air
interface quality
2. Perform targeted optimization for
different handover parameters
(magnetic hysteresis parameters
and CIO)
1. Check and optimize channels
and TMAs to address the
problem of severe path loss
imbalance between the uplink
and downlink
1. Provide optimization
suggestions on antenna
downtilts for cells
experiencing overshoot
coverage or weak intensive
coverage
1. Provide accurate frequency
optimization suggestions
based on interference
measurement results and
changes associated with PCI
optimization
RF root causes
Parameter classification for optimization in specific problematic scenarios
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Introduction to Themes on the OMStar
1. Start the OMStar.
2. Create a project. 3. Select a theme.
Tool: OMStar V500R012C00
Download address:http://support.huawei.com/carrier/navi#col=software&allProduct=true&path=PBI1-7275736/PBI1-9855723/PBI1-7497478/PBI1-59728
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Introduction to Themes on the OMStar
4. Import data.
Import data using one of the following
methods:
Import NIC packages in batches.
Import different types of data collected
from the M2000/U2000 one by one
Data Source (Data Marked
with Asterisks Are
Mandatory.)
Specifications
* External CHR data (SIG) 8 GB
*Performance data (MRF) 50 MB
*Configuration file (XML) 500 MB
*Engineering parameters
(XLS/XLSX)
20 MB
Operation log 500 MB
Alarm log (CSV) 50 MB
License file (TXT) 50 MB
Number of cells 300
Data collection period
6 busy hours in
three days
(3 days x 2 busy
hours)
High
efficiency in
importing NIC
packages
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Introduction to Themes on the OMStar
5. Create an analysis task. 6. Select NEs for analysis.
Analyzing all NEs, manually selecting NEs,
and analyzing cell groups are supported.
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Introduction to Themes on the OMStar
7. Set required parameters. 8. Select the time period of performance data for analysis.
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LTE Throughput Rate Optimization Delivery Guide
• Input
Theme-related data sources (XML configuration data, engineering parameters, MRF
performance data, SIG file, alarm data, operation log, and license query record)
Parameter configuration rules
Automatic analysis on the OMStar
• Output
TopN cell evaluation reports
Problem analysis reports
Optimization suggestions
• NE versions supported by OSs
BTS3900 V100R008C00
BTS3900 V100R008C01
BTS3900 V100R009C00
Field Name Description Remarks
eNodeBID Indicates the ID of an eNodeB. Mandatory
Cellid Indicates the ID of a cell. Mandatory
PCI Indicates the physical cell ID. Mandatory
CellName Indicate the name of a cell. Optional
Uarfcn Indicates the cell frequency. Mandatory
Longitude
Indicates the longitude where
an eNodeB is deployed.
Mandatory
Latitude
Indicates the latitude where an
eNodeB is deployed.
Mandatory
Azimuth Indicates the azimuth of a cell. Mandatory
IsOutDoor
Indicates whether a cell is an
outdoor cell.
Yes indicates outdoor,
and No indicates indoor.
Description of engineering parameter fields
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Optimization Report Interpretation
Non-Air Interface Problem Optimization Suggestion Sheet
Parameter check Parameter Check Result
Transmission issue Transmission Related Problem Advice
NE fault Hardware Related Problem Advice
Antenna channel Antenna Channel Related Problem Advice
Cell capacity congestion Cell Capacity Problem Advice
UE UE Problem Advice
Mapping between demarcation results and optimization suggestions
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Root Cause Optimization Suggestion Sheet Filtering Condition
Missing configuration of neighboring cells Adding neighboring cells
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting missing configurations of neighboring cells is higher than 5%.
Overlap coverage Adding neighboring cells
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting overshoot island coverage p is higher than 5%.
Handover delay
Cell-level optimization suggestions on delayed
handovers and cell-specific optimization
suggestions on delayed handovers
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting delayed handovers is higher than 5%.
Link exception
Adding optimization suggestions on link
exceptions
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting link exceptions is higher than 5%.
No primary serving cell
Adding optimization suggestions for no
primary serving cell problems
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting no primary serving cell is higher than 5%.
In-depth weak coverage
Adding optimization suggestions for in-depth
weak coverage problems.
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting intensive weak coverage is higher than 5%.
Edge weak coverage
Adding optimization suggestions for edge
weak coverage problems.
The proportion of MRs reporting poor service quality due to weak coverage is higher than 2%.
The proportion of MRs reporting intensive weak coverage is higher than 5%.
Handover-based interference due to missing
configurations of inter-frequency neighboring cells
Adding optimization suggestions for the
neighboring cells
The proportion of MRs reporting poor service quality due to interference is higher than 2%. The
proportion of MRs reporting missing configurations of inter-frequency neighboring cells is higher
than 5%.
Handover-based interfere due to inter-frequency
handover delays
Adding cell-level optimization suggestions,
and cell-to-cell optimization suggestions for
handover delay problems
The proportion of MRs reporting poor service quality due to interference is higher than 2%. The
proportion of MRs reporting interference due to delayed inter-frequency handovers is higher than
5%.
Overlap interference
Adding optimization suggestions for overlap
interference problems
The proportion of MRs reporting poor service quality due to interference is higher than 2%. The
proportion of MRs reporting overshoot coverage is higher than 5%. The proportion of MRs
reporting interference from neighboring cells to the serving cell is higher than 5%.
Interference due to azimuth exceptions
PCI check result
The proportion of MRs poor service quality due to interference is higher than 2%. The proportion
of MRs reporting azimuth exceptions of a single cell is higher than 5%.
PCI mod 3 interference
Pilot pollution
Adding optimization suggestions for pilot
pollution problems
The proportion of MRs reporting poor service quality due to interference is higher than 2%. The
proportion of MRs reporting pilot pollution is higher than 5%.
Mapping between root cause locating results and optimization suggestions
Optimization Report Interpretation
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Appendix 1: Throughput Rate Calculation Principles
• Total number of symbols
› 100 RBs x 12 Carriers x14 Symbols
• Cell-specific RS
› 16 resource elements (REs) are available for each subframe in cells have two-port antennas. Overhead = 16/(14 x 12)
= 9.5%
• P-SCH and S-SCH
› The center bandwidth 1.08 MHz is occupied, where the signal occupies 62 subcarriers and five carriers at each side
act as protection zones.
› Overhead = 2 x [(65 + 5 + 5) x 2/(14 x 12 x 100)]/10 ms = 0.2%
• PDCCH
› The PDCCH occupies one to three OFDM symbols. The estimated number of OFDM symbols is the average value 2:
(1 + 2 + 3)/3 = 2.
› Overhead = (2 x 12 – 14)/(14 x 12) = 12% (excluding REs occupied by the RS)
• PCFICH and PHICH
› The PCFICH occupies four REGs, and the PHICH occupies three REGs.
› Overhead = (4 x 4 + 3 x 4)/(14 x 12 x 100) = 0.17%
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• Broadcast channel
› PBCH: The first four OFDM symbols for each wireless frame with slot No. 1 are obtained: [(4 x 72)/(14 x 12 x 100)]/10 ms =
0.2%
› The SIB-1 period is 20 ms, the number of occupied RBs is 13, and the occupation overhead is calculated: (13/100)/20 ms =
0.65%
› The SI-1 period is 40 ms, the number of occupied RBs is 12, and the occupation overhead is calculated: (12/100)/40 ms =
0.3%
› The SI-2 period is 80 ms, the number of occupied RBs is 19, and the occupation overhead is calculated: (19/100)/80 ms =
0.24%
› The SI-3 period is 80 ms, the number of occupied RBs is 41, and the occupation overhead is calculated: (41/100)/80 ms =
0.51%
› The SI-4 period is 160 ms, the number of occupied RBs is 32, and the occupation overhead is calculated: (32/100)/160 ms
= 0.2%
› The SI-5 period is 160 ms, the number of occupied RBs is 32, and the occupation overhead is calculated: (32/100)/160 ms
= 0.2%
› Delivering information about SI from 1 to 5 is optional. The half overhead value is calculated and SIB-1 is added so the total
overhead is 1.375%.
• FDD peak value
› If the coding rate is 1 and 64QAM modulation mode used (each RE occupies 6 bits), the peak rate is calculated using the
following formula in 20 MHz LTE signal 2 x 2 MIMO: [100 x 12 x 14 x (1 – 9.5% – 0.2% – 12% – 0.17% – 0.2% – 1.375%) x
6 x 2]/1 ms = 154.33 Mbit/s
Appendix 1: Throughput Rate Calculation Principles
33. HISILICON SEMICONDUCTOR
HUAWEI TECHNOLOGIES CO., LTD. Page 33
HUAWEI Confidential
Attached RS
Positions
0
l
0
R
0
R
0
R
0
R
6
l 0
l
0
R
0
R
0
R
0
R
6
l
One
antenna
port
Two
antenna
ports
Resource element (k,l)
Not used for transmission on this antenna port
Reference symbols on this antenna port
0
l
0
R
0
R
0
R
0
R
6
l 0
l
0
R
0
R
0
R
0
R
6
l 0
l
1
R
1
R
1
R
1
R
6
l 0
l
1
R
1
R
1
R
1
R
6
l
0
l
0
R
0
R
0
R
0
R
6
l 0
l
0
R
0
R
0
R
0
R
6
l 0
l
1
R
1
R
1
R
1
R
6
l 0
l
1
R
1
R
1
R
1
R
6
l
Four
antenna
ports
0
l 6
l 0
l
2
R
6
l 0
l 6
l 0
l 6
l
2
R
2
R
2
R
3
R
3
R
3
R
3
R
even-numbered slots odd-numbered slots
Antenna port 0
even-numbered slots odd-numbered slots
Antenna port 1
even-numbered slots odd-numbered slots
Antenna port 2
even-numbered slots odd-numbered slots
Antenna port 3