The document provides definitions, influencing factors, analysis processes, optimization methods, and test methods for optimizing the inter-RAT handover success rate between 2G and 3G networks. It introduces the recommended formulas for calculating the success rates of incoming and outgoing inter-RAT handovers. Potential influencing factors that could decrease the success rates are discussed, including hardware failures, transmission problems, version upgrades, MS problems, improper parameter settings, unbalanced traffic volumes, interference, and coverage issues. Optimization processes and methods for locating problems and checking specific issues are also outlined.
This documents will help to understand the details procedure of GSM IDLE Mode Behavior. GSM Idle mode behavior starting from PLMN selection, GSM Cell Camp, Cell Selection, Cell Reselection, Location Update, Paging, System Information to Measurements procedures have been captured in this document.
Call Setup Success Rate Definition and Troubleshooting Assim Mubder
The CSSR indicates the probability of successful calls initiated by the MS. The CSSR is an important KPI for evaluating the network performance. If this KPI is too low, the subscribers are not likely to make calls successfully. The user experience is thus affected.
. Overview
2. Handover Causes & Priorities
3. Threshold Comparison Process
4. Target Cell Evaluation Process
5. Handover Algorithms
Power Budget (PBGT)
Level & Quality (RXLEV & RXQUAL)
Umbrella (& Combined Umbrella/PBGT)
MS Speed (FMMS & MS_SPEED_DETECTION)
6. Imperative Handovers
Distance
Rapid Field Drop (RFD) & Enhanced Rapid Field Drop (ERFD)
7. Handover Timers
Call continuity - to ensure a call can be maintained as a MS moves geographical location from the coverage area of one cell to another
Call quality - to ensure that if an MS moves into a poor quality/coverage area the call can be moved from the serving cell to a neighbouring cell (with better quality) without dropping the call
Traffic Reasons - to ensure that the traffic within the network is optimally
distributed between the different layers/bands of a network
If 2 or more handover (PC) criteria are satisfied simultaneously the following priority list
is used in determining which process is performed;
. Uplink and downlink Interference
2. Uplink quality
3. Downlink quality
4. Uplink level
5. Downlink level
6. Distance
7. Enhanced (RFD)
8. Rapid Field Drop (RFD)
9. Slow moving MS
10. Better cell i.e. Periodic check (Power Budget HO or Umbrella HO)
11. PC: Lower quality/level thresholds (UL/DL)
12. PC: Upper quality/level thresholds (UL/DL)
Pci mod3,6,30 analysis and auto optimizationShuangquan Lei
This presentation introduce a network optimization platform, and with this application, system will support you to find 4G LTE cells which have PCI MOD(3), MOD(6) and MOD(30) collision, and then can generate candidate value list by big data analysis.
Please send email to me if this application can make your work more effective.
my email address: lei.shuangquan@gmail.com
This documents will help to understand the details procedure of GSM IDLE Mode Behavior. GSM Idle mode behavior starting from PLMN selection, GSM Cell Camp, Cell Selection, Cell Reselection, Location Update, Paging, System Information to Measurements procedures have been captured in this document.
Call Setup Success Rate Definition and Troubleshooting Assim Mubder
The CSSR indicates the probability of successful calls initiated by the MS. The CSSR is an important KPI for evaluating the network performance. If this KPI is too low, the subscribers are not likely to make calls successfully. The user experience is thus affected.
. Overview
2. Handover Causes & Priorities
3. Threshold Comparison Process
4. Target Cell Evaluation Process
5. Handover Algorithms
Power Budget (PBGT)
Level & Quality (RXLEV & RXQUAL)
Umbrella (& Combined Umbrella/PBGT)
MS Speed (FMMS & MS_SPEED_DETECTION)
6. Imperative Handovers
Distance
Rapid Field Drop (RFD) & Enhanced Rapid Field Drop (ERFD)
7. Handover Timers
Call continuity - to ensure a call can be maintained as a MS moves geographical location from the coverage area of one cell to another
Call quality - to ensure that if an MS moves into a poor quality/coverage area the call can be moved from the serving cell to a neighbouring cell (with better quality) without dropping the call
Traffic Reasons - to ensure that the traffic within the network is optimally
distributed between the different layers/bands of a network
If 2 or more handover (PC) criteria are satisfied simultaneously the following priority list
is used in determining which process is performed;
. Uplink and downlink Interference
2. Uplink quality
3. Downlink quality
4. Uplink level
5. Downlink level
6. Distance
7. Enhanced (RFD)
8. Rapid Field Drop (RFD)
9. Slow moving MS
10. Better cell i.e. Periodic check (Power Budget HO or Umbrella HO)
11. PC: Lower quality/level thresholds (UL/DL)
12. PC: Upper quality/level thresholds (UL/DL)
Pci mod3,6,30 analysis and auto optimizationShuangquan Lei
This presentation introduce a network optimization platform, and with this application, system will support you to find 4G LTE cells which have PCI MOD(3), MOD(6) and MOD(30) collision, and then can generate candidate value list by big data analysis.
Please send email to me if this application can make your work more effective.
my email address: lei.shuangquan@gmail.com
Comparison of Different Control Strategies for Rotary Flexible Arm Jointomkarharshe
The problem of joint flexibility was of critical importance since the use of robot started in the fields such as space science and surveillance. This work investigates different control strategies to find the optimal solution to the problem. Sliding mode controller with Proportional- Integral state observer proves to be the best technique.
that can address this issue and compares the performance to d for addresses this issue by applying a stabilizing control law, ensuring robustness against plant uncertainties and disturbances.
A Study of Traffic Management Detection Methods & ToolsMartin Geddes
This scientific report was commissioned by the UK telecoms regulator, Ofcom, from Predictable Network Solutions Ltd. It evaluates the suitability of different traffic management techniques for regulatory use. The conclusions are very significant for the "net neutrality" debate, since it points out many common misconceptions about how broadband actually works.
Global Available to Promise with SAP: Functionality and ConfigurationSandeep Pradhan
• Master core functionalities and configuration techniques
• Explore how global ATP works and integrates with other key SAP software
• Optimize your global ATP functionalities to suit specific business processes
Automatic Detection of Performance Design and Deployment Antipatterns in Comp...Trevor Parsons
Enterprise applications are becoming increasingly complex. In recent times they have moved away from monolithic architectures to more distributed systems made up of a collection of heterogonous servers. Such servers generally host numerous soft- ware components that interact to service client requests. Component based enterprise frameworks (e.g. JEE or CCM) have been extensively adopted for building such ap- plications. Enterprise technologies provide a range of reusable services that can assist developers building these systems. Consequently developers no longer need to spend time developing the underlying infrastructure of such applications, and can instead concentrate their efforts on functional requirements.
Poor performance design choices, however, are common in enterprise applications and have been well documented in the form of software antipatterns. Design mistakes generally result from the fact that these multi-tier, distributed systems are extremely complex and often developers do not have a complete understanding of the entire ap- plication. As a result developers can be oblivious to the performance implications of their design decisions. Current performance testing tools fail to address this lack of system understanding. Most merely profile the running system and present large vol- umes of data to the tool user. Consequently developers can find it extremely difficult to identify design issues in their applications. Fixing serious design level performance problems late in development is expensive and can not be achieved through ”code op- timizations”. In fact, often performance requirements can only be met by modifying the design of the application which can lead to major project delays and increased costs.
This thesis presents an approach for the automatic detection of performance design and deployment antipatterns in enterprise applications built using component based frameworks. Our main aim is to take the onus away from developers having to sift through large volumes of data, in search of performance bottlenecks in their applica- tions. Instead we automate this process. Our approach works by automatically recon- structing the run-time design of the system using advanced monitoring and analysis techniques. Well known (predefined) performance design and deployment antipat- terns that exist in the reconstructed design are automatically detected. Results of ap- plying our technique to two enterprise applications are presented.
The main contributions of this thesis are (a) an approach for automatic detection of performance design and deployment antipatterns in component based enterprise frameworks, (b) a non-intrusive, portable, end-to-end run-time path tracing approach for JEE and (c) the advanced analysis of run-time paths using frequent sequence mining to automatically identify interesting communication patterns between com- ponents.
Similar to 16 gsm bss network kpi (inter rat handover success rate) optimization manual[1].doc (20)
Cosmetic shop management system project report.pdfKamal Acharya
Buying new cosmetic products is difficult. It can even be scary for those who have sensitive skin and are prone to skin trouble. The information needed to alleviate this problem is on the back of each product, but it's thought to interpret those ingredient lists unless you have a background in chemistry.
Instead of buying and hoping for the best, we can use data science to help us predict which products may be good fits for us. It includes various function programs to do the above mentioned tasks.
Data file handling has been effectively used in the program.
The automated cosmetic shop management system should deal with the automation of general workflow and administration process of the shop. The main processes of the system focus on customer's request where the system is able to search the most appropriate products and deliver it to the customers. It should help the employees to quickly identify the list of cosmetic product that have reached the minimum quantity and also keep a track of expired date for each cosmetic product. It should help the employees to find the rack number in which the product is placed.It is also Faster and more efficient way.
Saudi Arabia stands as a titan in the global energy landscape, renowned for its abundant oil and gas resources. It's the largest exporter of petroleum and holds some of the world's most significant reserves. Let's delve into the top 10 oil and gas projects shaping Saudi Arabia's energy future in 2024.
Industrial Training at Shahjalal Fertilizer Company Limited (SFCL)MdTanvirMahtab2
This presentation is about the working procedure of Shahjalal Fertilizer Company Limited (SFCL). A Govt. owned Company of Bangladesh Chemical Industries Corporation under Ministry of Industries.
HEAP SORT ILLUSTRATED WITH HEAPIFY, BUILD HEAP FOR DYNAMIC ARRAYS.
Heap sort is a comparison-based sorting technique based on Binary Heap data structure. It is similar to the selection sort where we first find the minimum element and place the minimum element at the beginning. Repeat the same process for the remaining elements.
Understanding Inductive Bias in Machine LearningSUTEJAS
This presentation explores the concept of inductive bias in machine learning. It explains how algorithms come with built-in assumptions and preferences that guide the learning process. You'll learn about the different types of inductive bias and how they can impact the performance and generalizability of machine learning models.
The presentation also covers the positive and negative aspects of inductive bias, along with strategies for mitigating potential drawbacks. We'll explore examples of how bias manifests in algorithms like neural networks and decision trees.
By understanding inductive bias, you can gain valuable insights into how machine learning models work and make informed decisions when building and deploying them.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
NO1 Uk best vashikaran specialist in delhi vashikaran baba near me online vas...Amil Baba Dawood bangali
Contact with Dawood Bhai Just call on +92322-6382012 and we'll help you. We'll solve all your problems within 12 to 24 hours and with 101% guarantee and with astrology systematic. If you want to take any personal or professional advice then also you can call us on +92322-6382012 , ONLINE LOVE PROBLEM & Other all types of Daily Life Problem's.Then CALL or WHATSAPP us on +92322-6382012 and Get all these problems solutions here by Amil Baba DAWOOD BANGALI
#vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore#blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #blackmagicforlove #blackmagicformarriage #aamilbaba #kalajadu #kalailam #taweez #wazifaexpert #jadumantar #vashikaranspecialist #astrologer #palmistry #amliyaat #taweez #manpasandshadi #horoscope #spiritual #lovelife #lovespell #marriagespell#aamilbabainpakistan #amilbabainkarachi #powerfullblackmagicspell #kalajadumantarspecialist #realamilbaba #AmilbabainPakistan #astrologerincanada #astrologerindubai #lovespellsmaster #kalajaduspecialist #lovespellsthatwork #aamilbabainlahore #Amilbabainuk #amilbabainspain #amilbabaindubai #Amilbabainnorway #amilbabainkrachi #amilbabainlahore #amilbabaingujranwalan #amilbabainislamabad
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
Hybrid optimization of pumped hydro system and solar- Engr. Abdul-Azeez.pdffxintegritypublishin
Advancements in technology unveil a myriad of electrical and electronic breakthroughs geared towards efficiently harnessing limited resources to meet human energy demands. The optimization of hybrid solar PV panels and pumped hydro energy supply systems plays a pivotal role in utilizing natural resources effectively. This initiative not only benefits humanity but also fosters environmental sustainability. The study investigated the design optimization of these hybrid systems, focusing on understanding solar radiation patterns, identifying geographical influences on solar radiation, formulating a mathematical model for system optimization, and determining the optimal configuration of PV panels and pumped hydro storage. Through a comparative analysis approach and eight weeks of data collection, the study addressed key research questions related to solar radiation patterns and optimal system design. The findings highlighted regions with heightened solar radiation levels, showcasing substantial potential for power generation and emphasizing the system's efficiency. Optimizing system design significantly boosted power generation, promoted renewable energy utilization, and enhanced energy storage capacity. The study underscored the benefits of optimizing hybrid solar PV panels and pumped hydro energy supply systems for sustainable energy usage. Optimizing the design of solar PV panels and pumped hydro energy supply systems as examined across diverse climatic conditions in a developing country, not only enhances power generation but also improves the integration of renewable energy sources and boosts energy storage capacities, particularly beneficial for less economically prosperous regions. Additionally, the study provides valuable insights for advancing energy research in economically viable areas. Recommendations included conducting site-specific assessments, utilizing advanced modeling tools, implementing regular maintenance protocols, and enhancing communication among system components.
NUMERICAL SIMULATIONS OF HEAT AND MASS TRANSFER IN CONDENSING HEAT EXCHANGERS...ssuser7dcef0
Power plants release a large amount of water vapor into the
atmosphere through the stack. The flue gas can be a potential
source for obtaining much needed cooling water for a power
plant. If a power plant could recover and reuse a portion of this
moisture, it could reduce its total cooling water intake
requirement. One of the most practical way to recover water
from flue gas is to use a condensing heat exchanger. The power
plant could also recover latent heat due to condensation as well
as sensible heat due to lowering the flue gas exit temperature.
Additionally, harmful acids released from the stack can be
reduced in a condensing heat exchanger by acid condensation. reduced in a condensing heat exchanger by acid condensation.
Condensation of vapors in flue gas is a complicated
phenomenon since heat and mass transfer of water vapor and
various acids simultaneously occur in the presence of noncondensable
gases such as nitrogen and oxygen. Design of a
condenser depends on the knowledge and understanding of the
heat and mass transfer processes. A computer program for
numerical simulations of water (H2O) and sulfuric acid (H2SO4)
condensation in a flue gas condensing heat exchanger was
developed using MATLAB. Governing equations based on
mass and energy balances for the system were derived to
predict variables such as flue gas exit temperature, cooling
water outlet temperature, mole fraction and condensation rates
of water and sulfuric acid vapors. The equations were solved
using an iterative solution technique with calculations of heat
and mass transfer coefficients and physical properties.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
1. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Product Name Confidentiality Level
G3BSC INTERNAL
Product Version Total 25 pages
GSM BSS Network KPI (Inter-RAT Handover
Success Rate) Optimization Manual
(For internal use only)
Prepared by Zhao Kang, WCDMA&GSM Network
Performance Research Dept.
Date
2009-03-24
Reviewed by Date
Reviewed by Date
Granted by Date
Huawei Technologies Co., Ltd.
All rights reserved
2014-6-18 Huawei Technologies Proprietary Page 1 of 25
2. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Contents
1 Definition of the Inter-RAT Handover Success Rate.............................................................7
1.1 Definition..................................................................................................................................................................7
1.1 Definition..................................................................................................................................................................7
1.2 Recommended Formulas.........................................................................................................................................7
1.2 Recommended Formulas.........................................................................................................................................7
1.2.1 Success Rate of Incoming Inter-RAT Inter-Cell Radio Handover......................................................................7
1.2.1 Success Rate of Incoming Inter-RAT Inter-Cell Radio Handover......................................................................7
1.2.2 Success Rate of Outgoing Inter-RAT Inter-Cell Radio Handover......................................................................8
1.2.2 Success Rate of Outgoing Inter-RAT Inter-Cell Radio Handover......................................................................8
1.3 Signaling Procedure and Measurement Points.........................................................................................................8
1.3 Signaling Procedure and Measurement Points.........................................................................................................8
2 Influencing Factors......................................................................................................................10
2.1 Hardware Failure....................................................................................................................................................10
2.1 Hardware Failure....................................................................................................................................................10
2.2 Transmission Problems...........................................................................................................................................10
2.2 Transmission Problems...........................................................................................................................................10
2.3 Version Upgrade.....................................................................................................................................................10
2.3 Version Upgrade.....................................................................................................................................................10
2.4 MS Problems...........................................................................................................................................................11
2.4 MS Problems...........................................................................................................................................................11
2.5 Improper Parameter Settings..................................................................................................................................11
2.5 Improper Parameter Settings..................................................................................................................................11
2.6 Unbalanced Traffic Volume....................................................................................................................................13
2.6 Unbalanced Traffic Volume....................................................................................................................................13
2.7 Intra-Network and Inter-Network Interference......................................................................................................14
2.7 Intra-Network and Inter-Network Interference......................................................................................................14
2.8 Coverage Problems................................................................................................................................................14
2.8 Coverage Problems................................................................................................................................................14
3 Analysis Process and Optimization Method..........................................................................15
3.1 Analysis Process.....................................................................................................................................................15
3.1 Analysis Process.....................................................................................................................................................15
2014-6-18 Huawei Technologies Proprietary Page 2 of 25
3. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
3.2 Problem Location and Optimization Methods........................................................................................................16
3.2 Problem Location and Optimization Methods........................................................................................................16
3.2.1 Checking the Hardware Status of the Cells with High Inter-RAT Handover Success Rate.............................16
3.2.1 Checking the Hardware Status of the Cells with High Inter-RAT Handover Success Rate.............................16
3.2.2 Checking the Transmission in the Cells with High Inter-RAT Handover Success Rate..................................17
3.2.2 Checking the Transmission in the Cells with High Inter-RAT Handover Success Rate..................................17
3.2.3 Checking the Problems Caused by BSC Version Upgrade and BTS Version Upgrade....................................18
3.2.3 Checking the Problems Caused by BSC Version Upgrade and BTS Version Upgrade....................................18
3.2.4 Checking the Parameter Settings in the Cells with High Inter-RAT Handover Success Rate..........................18
3.2.4 Checking the Parameter Settings in the Cells with High Inter-RAT Handover Success Rate..........................18
3.2.5 Checking the Interference in the Cells with High Inter-RAT Handover Success Rate....................................19
3.2.5 Checking the Interference in the Cells with High Inter-RAT Handover Success Rate....................................19
3.2.6 Checking the Conditions of Coverage, Antenna, and Balance Between Uplink and Downlink in the Cells
with High Inter-RAT Handover Success Rate...........................................................................................................20
3.2.6 Checking the Conditions of Coverage, Antenna, and Balance Between Uplink and Downlink in the Cells
with High Inter-RAT Handover Success Rate...........................................................................................................20
3.2.7 Checking the Repeaters in the Cells with Low Inter-RAT Handover Success Rate.........................................21
3.2.7 Checking the Repeaters in the Cells with Low Inter-RAT Handover Success Rate.........................................21
4 Test Methods................................................................................................................................22
5 Optimization Cases....................................................................................................................23
5.1 Case 1: Data Configuration....................................................................................................................................23
5.1 Case 1: Data Configuration....................................................................................................................................23
5.2 Case 2: Inter-RAT Handover Success Rate Decreasing Caused by Data Configuration.......................................24
5.2 Case 2: Inter-RAT Handover Success Rate Decreasing Caused by Data Configuration.......................................24
6 Information Feedback ................................................................................................................25
2014-6-18 Huawei Technologies Proprietary Page 3 of 25
4. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Revision Record
Date Version Description Author
2008-12-25 V10 Initial draft Zhao Kang
References
SN Document Author Date
1 GSM BSS Network KPI (Inter-RAT Handover Success Rate)
Baseline
Wu Zhen
Zhao Jinjin
2014-6-18 Huawei Technologies Proprietary Page 5 of 25
5. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Network KPI (Inter-RAT Handover Success Rate) Optimization
Manual
Keywords: Inter-RAT handover success rate
Abstract: This document introduces the definition, test methods, and optimization methods of
the inter-RAT handover success rate.
Acronyms and Abbreviations:
Abbreviation Full Spelling
2014-6-18 Huawei Technologies Proprietary Page 6 of 25
6. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
1 Definition of the Inter-RAT Handover
Success Rate
1.1 Definition
The success rate of incoming inter-RAT inter-cell radio handover refers to the ratio of the total
number of successful handovers from 3G cell to 2G cell triggered by all causes to the total
number of handover requests from 3G cell to 2G cell triggered by all causes.
The success rate of outgoing inter-RAT inter-cell radio handover refers to the ratio of the total
number of successful handovers from 2G cell to 3G cell triggered by all causes to the total
number of handover commands from 2G cell to 3G cell triggered by all causes.
Both the success rate of incoming inter-RAT inter-cell radio handover and the success rate of
outgoing inter-RAT inter-cell radio handover are important retainability KPIs. The KPIs
directly affect the experience of 2G/3G users and are most significant KPIs for the operators
to appraise the 2G/3G network interoperability.
1.2 Recommended Formulas
1.2.1 Success Rate of Incoming Inter-RAT Inter-Cell Radio
Handover
The success rate of incoming inter-RAT inter-cell radio handover is obtained on the basis of
the traffic measurement. The recommended formula is as follows:
Number of successful incoming inter-RAT inter-cell handovers/Number of incoming inter-
RAT inter-cell handover responses.
In the BSC6000, the recommended formula is as follows:
Success rate of incoming inter-RAT inter-cell radio handover = Number of successful
incoming inter-RAT inter-cell handovers/Number of Incoming inter-RAT inter-cell handover
responses x 100% = CH363/CH361 x 100%
2014-6-18 Huawei Technologies Proprietary Page 7 of 25
7. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
1.2.2 Success Rate of Outgoing Inter-RAT Inter-Cell Radio
Handover
The success rate of outgoing inter-RAT inter-cell radio handover is obtained on the basis of
the traffic measurement. The recommended formula is as follows: Number of successful
outgoing inter-RAT inter-cell handovers/Number of outgoing inter-RAT inter-cell handovers.
In the BSC6000, the recommended formula is as follows:
Success rate of outgoing inter-RAT inter-cell radio handover = Number of successful
outgoing inter-RAT inter-cell handovers/Number of outgoing inter-RAT inter-cell handovers x
100% = CH353/CH351 x 100%
For details, refer to the GSM BSS Network KPI (2G/3G Interoperability) Baseline.
1.3 Signaling Procedure and Measurement Points
Where:
A1 – Number of incoming inter-RAT inter-cell handover requests
B1 – Number of incoming inter-RAT inter-cell handover responses
C1 – Number of successful incoming inter-RAT inter-cell handovers
2014-6-18 Huawei Technologies Proprietary Page 8 of 25
8. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Where:
A2 - Number of outgoing inter-RAT inter-cell handover requests
B2 – Number of outgoing inter-RAT inter-cell handovers
C2 – Number of successful outgoing inter-RAT inter-cell handovers
The measurement points of 2G/3G interoperability KPIs are presented as follows:
Success rate of incoming inter-RAT inter-cell radio handover: C1/B1
Success rate of outgoing inter-RAT inter-cell radio handover: C2/B2
2014-6-18 Huawei Technologies Proprietary Page 9 of 25
9. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
2 Influencing Factors
According to user complaints and network optimization experience, the major factors that
affect the inter-RAT handover success rate are as follows:
Hardware failure
Transmission problems
Version upgrade
MS problems
Improper parameter settings
Unbalanced traffic volume
Intra-network and inter-network interference
Coverage problems
2.1 Hardware Failure
During the test, when a large number of terrestrial resources are unavailable or devices are
faulty, seizing the TCH becomes difficult. As a result, the inter-RAT handover success rate
decreases.
2.2 Transmission Problems
The inter-RAT handover success rate decreases in any of the following conditions: (1) The
transmission quality is bad on the A or Abis interface due to various reasons. (2) Transmission
links are unstable.
2.3 Version Upgrade
All the current versions of the BSC6000 of Huawei support the handover between the GSM
and the 3G UTRAN FDD system. The initial field trial release and later versions, that is, the
BSC6000V9R3 and later versions, support the handover between the GSM and the 3G
UTRAN TDD system. However, if the following restrictions exist, that is, a version does not
support the inter-RAT handover in FFD or TDD mode, the inter-RAT handover may fail. As a
result, the inter-RAT handover success rate decreases.
2014-6-18 Huawei Technologies Proprietary Page 10 of 25
10. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
2.4 MS Problems
Now, many operators take the sales strategy of presenting an MS for free after a subscriber
subscribes to 3G network services. Thus, most MSs are customized multi-mode MSs. To
implement special functions and features of operators, operators add and reduce some
functions from the MSs. In the network, when a type of MS always incurs handover failure,
the failure can be located through the MS-related support capability and parameter settings.
2.5 Improper Parameter Settings
The settings of some parameters of BSC and MSC also affect the inter-RAT handover success
rate. The main parameters include:
3G System
Information
Data Table
3G Search PRIO: Indicates whether the BISC is allowed to search for a
3G cell when the BISC must be decoded. Default value: Yes
Qsearch C: Indicates the signal level threshold for cell search in
connection mode. When the signal level in the serving cell is below (0–
7) or above (8–15), the MS starts to search for 3G cells.
Serving Band Reporting: Indicates the number of cells that are
contained in the best cell list in the current serving band.
FDD MULTIRAT Reporting: Indicates the number of UTRAN FDD
cells that are contained in the measurement report.
3G BA2 Table Provides the frequencies, scrambling codes, and diversity indication of
3G UTRAN FDD neighboring cells, and the basis for sorting 3G cells.
If the parameter is not set, the handover to 3G cell is impacted.
Early Classmark
Sending Control
(ECSC)
Indicates whether the MSs in a cell use early classmark sending. You
can send classmark 3 with the MS to determine whether the MS
supports 3G.
3G HO Data
table
Inter-RAT In BSC Handover Enable/Inter-RAT Out BSC Handover
Enable: Indicates whether the handover from 2G to 3G is allowed.
Recommended value during the 2G/3G interoperability: Yes
Better 3G Cell HO Allowed: Indicates whether the better 3G cell
handover algorithm is allowed. Yes indicates the handover algorithm is
allowed, and No indicates the handover algorithm is not allowed.
Recommended value during the 2G/3G interoperability: Yes
Inter-RAT HO Preference: Indicates whether an MS is preferentially
handed over to a 2G cell or a 3G cell.
HO Preference Threshold for 2G Cell: If the Inter-RAT HO
Preference parameter is set to Preference for 2G Cell By Threshold,
and if the receive level of the first candidate cell among 2G candidate
cells is lower than or equal to the HO Preference Threshold for 2G
Cell, the 3G cell handover is preferred; otherwise, the 2G cell handover
is preferred.
RSCP Threshold for Better 3G Cell HO: If Outgoing-RAT HO
Allowed is set to Yes and Better 3G Cell HO Allowed is also set to
Yes, a better 3G cell handover is triggered when the RSCP of a
2014-6-18 Huawei Technologies Proprietary Page 11 of 25
11. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
neighboring 3G cell is greater than RSCP Threshold for Better 3G
Cell HO. Default value: 50
Ec/No Threshold for Better 3G Cell HO: If Outgoing-RAT HO
Allowed is set to Yes and Better 3G Cell HO Allowed is also set to
Yes, a better 3G cell handover is triggered when the Ec/No of a
neighboring 3G cell is greater than Ec/No Threshold for Better 3G
Cell HO. Default value: 35
3G External
Cell
Indicates how to configure a 3G external cell and the neighboring cell
relation between the cell and a 2G cell.
During the 2G/3G interoperability, improper parameter settings affect cell reselection. As a
result, the subscriber distribution is impacted.
The parameters that affect the 2G/3G inter-RAT cell reselection are as follows:
Parameter Parameter Configuration
Inter-RAT Cell
Reselection Enable
Inter-RAT Cell Reselection Enable: Indicates whether the
reselection from a 2G cell to a 3G cell is allowed.
Recommended value during the 2G/3G interoperability: Yes
Equivalent PLMN Table Equivalent PLMN refers to the PLMN that can provide the
same services to subscribers as the current network does. This
parameter is set on the core network side. Set the peer PLMNs
of both 2G core network and 3G core network to Equivalent
PLMN.
3G BA1 Table To implement 2G/3G inter-RAT cell reselection, add the
corresponding cells to the neighboring cell table, and
configure the neighboring relation. The settings include the
downlink frequency, whose value ranges from 0 to 16383, of
the neighboring 3G cell, the scrambling code, whose value
ranges from 0 to 511, of the neighboring 3G cell, and the
diversity indication, whose value ranges from 0 to 1, of the
neighboring 3G cell. This parameter is set in the advanced idle
parameter table.
3G System Information
Data Table
MSC Version Information: Indicates the protocol version of
the MSC that works with the BSC. The supported signaling
varies with the protocol versions. Value range: R98 or R98
below and R99 or R99 above. Default value: R98 or R98
below.
This parameter is set in the advanced call-control parameter
table according to the actual MSC protocol version.
2014-6-18 Huawei Technologies Proprietary Page 12 of 25
12. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Parameter Parameter Configuration
Qsearch I: When the parameter is set to 0–7, the MS starts to
search for 3G cells if the signal level of the current serving
cell is lower than the level corresponding to the parameter.
When the parameter is set to 8–15, the MS starts to search for
3G cells if the signal level of the current serving cell is higher
than the level corresponding to the parameter. If this parameter
is set to 7, the MS searches for 3G cells all the time. If this
parameter is set to 15, the MS does not search for 3G cells at
all. The values 0 to 6 map to the following signal levels
respectively: –98 dBm, –94 dBm, –90 dBm, –86 dBm, –82
dBm, –78 dBm, and –74 dBm. The values 8 to 14 map to the
following signal levels respectively: –78 dBm, –74 dBm, –70
dBm, –66 dBm, –62 dBm, –58 dBm, and –54 dBm.
Qsearch C Initial: Specifies the mode in which an MS
searches for 3G cells. Value range: Always, Use Qsearch_I. If
this parameter is set to Always, an MS always searches for
neighboring 3G cells. If this parameter is set to Use
Qsearch_I, an MS starts to search for neighboring 3G cells
only when it meets the Qsearch I. Default value: Use
Qsearch_I
FDD Q Offset: Indicates that a 3G cell can become a
candidate cell for reselection only when the average receive
level of the 3G cell is FDD Q Offset greater than the average
receive level of the current serving cell. Value range: 0–15. If
the parameter is set to 0, it indicates that the reselection is
allowed as long as the FDD neighboring cell exists. The
values 1 to 15 correspond to the following levels respectively:
–28 dB, –24 dB, –20 dB, –16 dB, –12 dB, –8 dB, –4 dB, 0 dB,
4 dB, 8 dB, 12 dB, 16 dB, 20 dB, 24 dB, and 28 dB. Default
value: 0
FDD Qmin: Indicates that a 3G cell can become a candidate
cell for reselection only when the receive level of the 3G cell
is greater than FDD_Qmin. Value range: 0–7. The values 0 to
7 map to the following levels respectively: –20 dB, -19 dB, –
18 dB, -17 dB, –16 dB, -15 dB, –14 dB, and -13 dB. Default
value: 0 (-20 dB).
2.6 Unbalanced Traffic Volume
Traffic volume is unevenly distributed in the network in the test environment, such as burst
traffic. This causes the 3G or 2G network congestion. As a result, the inter-RAT handover
success rate decreases.
2014-6-18 Huawei Technologies Proprietary Page 13 of 25
13. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
2.7 Intra-Network and Inter-Network Interference
If inter-network interference and repeater interference exist, or if severe intra-network
interference occurs because of tight frequency reuse, call drops may occur on SD or TCH
channels due to bad QoS. This affects the inter-RAT handover success rate.
The following types of interference may occur:
1. Inter-network interference from scramblers or privately installed antennas
2. Repeater interference
3. Intermodulation interference from BTSs
4. Intra-network co-channel and adjacent-channel interference
5. Three-phrase intermodulation interference from other inter-network systems
2.8 Coverage Problems
The following coverage problems may affect the inter-RAT handover success rate:
1. Discontinuous coverage (blind areas)
In complex terrains covered by 3G BTSs and complex radio transmission environment, and at
the early construction stage of the 3G network, the inter-RAT handover success rate decreases
because of the discontinuous coverage of 3G signals.
2. Poor indoor coverage
Densely distributed buildings and thick walls cause great attenuation. In addition, the 2G and
3G signal loss difference causes 2G and 3G signal coverage difference. As a result, the inter-
RAT handover success rate decreases during a call.
3. Insufficient coverage
At the late construction stage of the 3G network, if the site is selected incorrectly, the signals
from antennas are blocked or the BCCH TRX is faulty. As a result, the inter-RAT handover
success rate decreases because of discontinuous coverage.
2014-6-18 Huawei Technologies Proprietary Page 14 of 25
14. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
3 Analysis Process and Optimization
Method
3.1 Analysis Process
2014-6-18 Huawei Technologies Proprietary Page 15 of 25
A problem in the whole network?
Antenna faulty? Adjust the antenna.
Add coverage optimization RF indexes.
Locate interference source.
Replace the version or install a patch.
Start
Data configuration problem?
Interference exists?
N
o
Yes
否
Insufficient coverage or blind area?
Transmission problem or hardware fault?
Adjust handover parameters
Solve the problem.
Yes
Traffic unevenly distributed? Optimize handover reselection parameters
Yes
End
Yes
Caused by version upgrade?
N
o
N
o
N
o
N
o
Yes
Yes
Yes
Yes
15. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
3.2 Problem Location and Optimization Methods
General ideas
To analyze an inter-RAT handover success rate problem, determine whether the problem
exists in a cell or in the whole network first of all. If the problem of low handover success rate
exists in the whole network, the relevant parameter may be set incorrectly. You must check
the parameter settings.
First, determine whether the problem is an outgoing inter-RAT handover problem or an
incoming inter-RAT handover problem through the analysis of traffic measurement.
Preliminarily find the handover failure causes through the analysis of the traffic statistics.
Secondly, if the problem exists in some cells in a certain area, you need to find the detailed
causes. Check whether the software version supports the 3G inter-RAT handover. Or view the
product release description of inter-RAT handover. Rectify the problems caused by the
defective software, version upgrade or version itself.
After rectifying the preceding problems, check whether the hardware and transmission in
these cells incur error, whether relevant alarms are generated, and whether these cells are in
normal status.
Check whether the traffic volume bursts or is congested. In this way, rectify the antenna
problem, insufficient coverage problem, and interference problem. Thus, finally rectify the
inter-RAT handover success rate problem.
Specific analysis methods and ideas
First, determine the handover failure scope through the analysis of traffic measurement. If the
inter-RAT handover success rate is low in all the cells, you need to rectify the problem by
checking the inter-RAT handover characteristics parameters, circuits on the A interface, and
BSC clock.
Secondly, classify the cells into the cells with low inter-RAT handover success rate and TOPN
cells, and then perform the following steps to rectify the problem.
Thirdly, check the success rate of outgoing inter-RAT inter-cell handover and success rate of
incoming inter-RAT inter-cell handover in the inter-RAT handover measurement.
Subsequently, analyze the outgoing/incoming inter-RAT inter-cell handover measurement of
faulty cells to find the cells to which handover failure occurs. Analyze the failure causes, and
make statistics of the distribution of these causes.
Fourthly, check the TRX availability of faulty cells to determine whether the failure is caused
by faulty devices.
Fifthly, check the number of A interface failures during TCH seizure and the number of
terrestrial link disconnections to determine whether the failure is caused by faulty terrestrial
link devices.
3.2.1 Checking the Hardware Status of the Cells with High Inter-
RAT Handover Success Rate
If a TRX or a combiner is faulty or if an RF cable is incorrectly connected, seizing the
SDCCH becomes difficult, and thus the inter-RAT handover success rate decreases.
2014-6-18 Huawei Technologies Proprietary Page 16 of 25
16. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
You can check whether hardware is faulty by viewing BTS alarms or viewing the hardware
state on the Site Device Panel of the LMT. The following table lists the major BSC alarms
related to hardware failures:
Alarm ID Alarm Name
1000 LAPD_OML fault
2204 TRX communication alarm
4414 TRX VSWR alarm
3606 DRU hardware alarm
In addition, you can locate the fault by checking the traffic measurement related to hardware
failures, as shown in the following table.
Cause BSC Level Cell Level
Equipment
faults
BSC Measurement -> Access
measurement per BSC ->
Congestion Ratio on SDCCH per
BSC
SDCCH Availability per BSC
Channel Measurement ->
Analyzed Measurement of Available
Channels (SDCCH)
Call Measurement -> Call Drop
Measurement
Call Drops due to Equipment Failure
(Signaling Channel)
3.2.2 Checking the Transmission in the Cells with High Inter-
RAT Handover Success Rate
Poor transmission quality, unstable transmission links, or insufficient resources on the Abis
and A interfaces may lead to the decrease of the inter-RAT handover success rate. You can
check the transmission conditions by viewing the alarms related to transmission. If a large
number of transmission alarms are generated, you can infer that transmission failures occur.
Then, you should check the transmission connections.
The following table lists the BSC alarms related to transmission failures:
Alarm ID Alarm Name
1000 LAPD_OML fault
11270 LAPD alarm
11278 E1 local alarm
11280 E1 remote alarm
20081 Loss of E1/T1 signals (LOS)
20082 Loss of E1/T1 frames (LOF)
2014-6-18 Huawei Technologies Proprietary Page 17 of 25
17. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
In addition, you can locate the fault by checking the traffic measurement related to
transmission failures, as shown in the following table.
Cause BSC Level Cell Level
Transmis
sion
failure
BSC Measurement -> LAPD
Measurement
Call Measurement -> Channel Activation
Measurement ->
CHAN ACTIV NACK Messages Sent by BTS
Channel Activation Timeouts
Call Measurement -> Call Drop Measurement
Measurement of Call Drops Due to Abis Link
Failure
3.2.3 Checking the Problems Caused by BSC Version Upgrade
and BTS Version Upgrade
If the inter-RAT handover success rate drops greatly after the BSC version or BTS version is
upgraded, you should check whether the BTS version is compatible with the BSC version and
whether the parameters and algorithms in the new version are changed.
To locate the problem, you can check the version description document and the related
documents, or provide the feedback to the Maintenance Team to learn whether the new
version has known defects. If the new version has defects, you should replace it with another
version or install a patch.
3.2.4 Checking the Parameter Settings in the Cells with High
Inter-RAT Handover Success Rate
The parameter settings on the BSC side and MSC side may affect the inter-RAT handover
success rate. You should check the settings of the following parameters for a faulty cell:
Outgoing-RAT HO Allowed: Indicates whether the outgoing system handover from 2G to
3G is allowed. Recommended value during the 2G/3G interoperability: Yes
Better 3G Cell HO Allowed: Indicates whether the better 3G cell handover algorithm is
allowed. Yes indicates the handover algorithm is allowed, and No indicates the handover
algorithm is not allowed. Recommended value during the 2G/3G interoperability: Yes
Inter RAN Load Information Allowed: Indicates whether to use the information about the
load of 3G neighboring cells for load handover decision.
Recommended value during the 2G/3G interoperability: Yes
Inter-RAT HO Preference: Indicates whether an MS is preferentially handed over to a 2G
cell or a 3G cell.
HO Preference Threshold for 2G Cell: If Inter-RAT HO Preference is set to HO
Preference Threshold for 2G Cell, and if the receive level of the first candidate cell among
2014-6-18 Huawei Technologies Proprietary Page 18 of 25
18. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
2G candidate cells is less than or equal to Pre_2G_CellThres, the 3G cell handover is
preferred; otherwise, the 2G cell handover is preferred.
RSCP Threshold for Better 3G Cell HO: If Outgoing-RAT HO Allowed is set to Yes and
Better 3G Cell HO Allowed is also set to Yes, a better 3G cell handover is triggered when the
RSCP of a neighboring 3G cell is greater than RSCP Threshold for Better 3G Cell HO.
Default value: 50
Ec/No Threshold for Better 3G Cell HO: If Outgoing-RAT HO Allowed is set to Yes and
Better 3G Cell HO Allowed is also set to Yes, a better 3G cell handover is triggered when the
Ec/No of a neighboring 3G cell is greater than Ec/No Threshold for Better 3G Cell HO.
Default value: 35
3G Search PRIO: Indicates whether the BISC is allowed to search for a 3G cell when the
BISC must be decoded. Default value: Yes
QSearch C: Indicates the signal level threshold for cell search in connection mode. When the
signal level in the serving cell is below (0–7) or above (8–15), the MS starts to search for 3G
cells.
Serving Band Reporting: Indicates the number of cells that are contained in the best cell list
in the current serving band.
FDD MULTIRAT Reporting: Indicates the number of UTRAN FDD cells that are contained
in the measurement report.
3.2.5 Checking the Interference in the Cells with High Inter-RAT
Handover Success Rate
If inter-network interference and repeater interference exist, or if severe intra-network
interference occurs because of tight frequency reuse, call drops may occur on SD or TCH
channels due to bad QoS. This affects the inter-RAT handover success rate.
The uplink interference information can be obtained on the basis of the interference band
distribution in the traffic measurement results. A large proportion of interference levels belong
to interference bands 3–5, you can infer that the uplink has strong interference. In this case,
you can view the interference band distribution at the TRX level based on the SD or TCH
measurement report.
The interference elimination can be classified into intra-network interference elimination and
inter-network interference elimination. For details about interference elimination, see the G-
Guide to Eliminating Interference.
2014-6-18 Huawei Technologies Proprietary Page 19 of 25
19. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
Cause TRX Level
Interference
MR Measurement ->
Interference Band Measurement ->
Mean Number of SDCCHs in Interference Band 1
Mean Number of SDCCHs in Interference Band 2
Mean Number of SDCCHs in Interference Band 3
Mean Number of SDCCHs in Interference Band 4
Mean Number of SDCCHs in Interference Band 5
MR Measurement ->
Interference Band Measurement ->
Mean Number of TCHFs in Interference Band 1
Mean Number of TCHFs in Interference Band 2
Mean Number of TCHFs in Interference Band 3
Mean Number of TCHFs in Interference Band 4
Mean Number of TCHFs in Interference Band 5
MR Measurement ->
Interference Band Measurement ->
Mean Number of TCHHs in Interference Band 1
Mean Number of TCHHs in Interference Band 2
Mean Number of TCHHs in Interference Band 3
Mean Number of TCHHs in Interference Band 4
Mean Number of TCHHs in Interference Band 5
3.2.6 Checking the Conditions of Coverage, Antenna, and Balance
Between Uplink and Downlink in the Cells with High Inter-RAT
Handover Success Rate
In the cells with high inter-RAT handover success rate, you can check the network coverage
through DT and CQT. Coverage problems or imbalance problems between UL and DL exist if
the following phenomena occurs: DL receive level is low; the difference between the UL level
and DL level is large in the measurement report viewed through the signaling, level quality
deteriorates gradually, the DL measurement report is lost, and call access is performed for a
long time.
In the cell where the preceding problems exist, the call establishment success rate and
handover success rate are impacted. The deteriorated receive quality is also reflected in the
quality traffic measurement. In addition, you can analyze the cell coverage based on the drive
test route and geographical condition, and troubleshoot the antenna system based on a fault
symptom. Some cell coverage problems and imbalance problems between UL and DL are
caused by the coverage direction and tilt angle of antennas, and damage, water penetration,
and loose connector of antenna feeders.
To rectify the preceding problems, see the following documents: GSM BSS Network KPI
(Coverage) Optimization Manual and GSM BSS Network KPI (Uplink and Downlink
Balance) Optimization Manual.
2014-6-18 Huawei Technologies Proprietary Page 20 of 25
20. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
3.2.7 Checking the Repeaters in the Cells with Low Inter-RAT
Handover Success Rate
Check whether the parameter Directly Magnifier Site Flag is set to Yes in the data
configuration on the LMT and whether the signaling channel handover is enabled. If this
parameter is set to Yes, you can infer that the cell is configured with repeaters. If this
parameter is set to No, you should check whether other operators' repeaters are installed near
the cell.
If repeaters are installed, check whether the type, operating frequency band and operating
bandwidth (broadband or narrowband) of the repeaters impact the inter-RAT handover
success rate. If it is, check whether the UL/DL magnifying coefficient is excessively high. If it
is, reduce the coefficient. If the impact is serious, disable the repeater.
In addition, you should check whether a repeater is faulty and whether the uplink/downlink
gain is set to a too great/small value. If this problem exists, the actual coverage area of the
BTS may different from the planed coverage area. Thus, the call drop rate increases.
If repeater problems exist in a cell, the TA distribution varies greatly in the traffic
measurement results. The following table lists the traffic measurement counters related to
repeaters.
Cause Cell Level TRX Level
Repeater None
MR Measurement ->
Number of MRs Based on TA
2014-6-18 Huawei Technologies Proprietary Page 21 of 25
21. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
4 Test Methods
The inter-RAT handover success rate can be obtained through the registration or reporting of
the related traffic measurement counters. Because the 3G system belongs to different
manufacturers, the inter-RAT handover may have cooperation problems. Thus, you need to
adjust the relevant parameters of the 3G system, and troubleshoot the 2G system based on the
preceding check.
2014-6-18 Huawei Technologies Proprietary Page 22 of 25
22. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
5 Optimization Cases
5.1 Case 1: Data Configuration
Problem description: In a site, the GSM network and UMTS network coexist. A customer
requires enabling the reselection from a 2G cell to a 3G cell, and disabling the handover from
the 2G cell to the 3G cell.
Problem analysis and handling: Based on the preceding analysis, set the BSC-related
parameters as follows:
1. Make a 3G external neighboring cell datasheet, and then import the datasheet to the BSC
through the mass import function of the LMT.
2. Set Inter-System Handover Enable to Yes.
3. Set the relevant parameters in the parameter table that is displayed by choosing Call
Control -> UTRAN System Message, thus ensuring the reselection from a 2G cell to a
3G cell. The parameters related to cell reselection contain Qsearch I, FDD Q Offset,
and FDD Qmin. The specific value can be set as required and the operation is beyond
the scope of this document.
The preceding settings ensure the reselection from a 2G cell to a 3G cell. Then, we
disable the handover from a 2G cell to a 3G cell:
4. Set Qsearch C to 15, which indicates that no 3G cell is searched in connection mode.
5. Set Inter-RAT HO Preference in the UTRAN FDD handover datasheet to Preference
for 2G Cell. That is, a 2G neighboring cell is selected preferentially in accordance with
the handover strategy.
6. Set the parameters in the 3G external neighboring table as follows:
Min RSCP Threshold = 63
Min Ec/No Threshold = 49
RSCP Threshold for Layer Of 3G Cell = 63
Ec/No Threshold for Layer Of 3G Cell = 49
Setting the RSCP threshold to 63 (maximum value) indicates that a 3G neighboring cell
cannot become a candidate neighboring cell until its receive level is greater than 63, that
is, -25 dBm. Setting the Ec/No threshold to 49 (maximum value) indicates that a 3G
neighboring cell cannot become a candidate neighboring cell until its signal-to-noise
ratio is greater than 0 dB. In this way, the handover from a 2G cell to a 3G cell is
disabled, because no 3G neighboring cell can meet so rigid RSCP and Ec/No thresholds
in practice. Then, by viewing the outgoing handover traffic measurement from a GSM
cell to a UMTS cell for a week, you can find that no handover request from a 2G cell to a
2014-6-18 Huawei Technologies Proprietary Page 23 of 25
23. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
cell 3G cell is initiated. It indicates that the preceding settings make us achieve expected
objectives.
5.2 Case 2: Inter-RAT Handover Success Rate Decreasing
Caused by Data Configuration
Problem description: The operator M in S country had used Huawei 2G equipment for two
years in Al kharj area. The network run normally and the network KPIs were stable. On
March 16, 2008, we suddenly found that the incoming BSC handover success rate of the
BSC132 had decreased drastically from 97% to 40% during KPI statistics.
Problem analysis and handling: After communicating with M's optimization department, we
find that the competitor A has deployed and powered on its 3G equipment in the area without
informing Huawei in advance, resulting in high failure rate of Huawei inter-BSC handover.
Huawei equipment version in the existing network:
BSC version:
G3BSC32V300R002C13SP54
BTS version:
BTS : GBT312G3BTS32V302R007C07B001
In the existing network, Huawei BSC132 is mounted on the MSC102 of competitor E, and the
RNC16 of competitor A is mounted on the MSC104 of competitor E. As a result, the inter-
RAT interoperability problem occurs between two systems of three manufacturers. Upon
coordination, three manufacturers performed the first combined DT on March 20, and drove
from a 2G/3G co-sited cell to a 2G coverage area. In addition, Huawei OMC was required to
trace signaling on the A interface and user plane at the same time. In the test process, we
found that the 3G UE sent a 2D event to the system and requested the handover when the
RSCP was weak, but the UE receives no response until the call was dropped. Through
analysis, it was found that Huawei BSC did not respond to the handover request. After
location, we found that the problem was concentrated on data configuration.
To check the data configuration of the BSC, first check the following aspects:
1. Encryption algorithm
2. MSC version supported by the BSC
3. Configuration of the external LAC
4. Enabling state of inter-RAT handover
After confirmation between Huawei and engineers of competitors A and E, we found that the
3G system adopted A5/1 algorithm, the current MSC version was R99, and the external LAC
had been added. Finally, the problem was concentrated on the setting of the inter system HO
allowed parameter in the Modify BSC Interface Phase ID table. After the parameter was set
to Yes, the inter-RAT handover was normal. Through CN signaling trace, the MSC104
received the handover complete message from the MSC102, and the success rate of Huawei
inter-BSC handover increases to the normal level.
2014-6-18 Huawei Technologies Proprietary Page 24 of 25
24. GSM BSS Network KPI (Inter-RAT Handover Success Rate) Optimization Manual INTERNAL
6 Information Feedback
If the call drop rate is high and technical support is required, fill in the following form:
Information Remarks Purpose
Software version Software versions of the BSC and
BTS
Check whether the software version is defective.
Data
configuration
table
*.dat files Check the network optimization parameters and
power configuration.
Alarm
information
Alarm information related to
hardware, clock, and transmission
(self-check)
Check whether such alarms are generated in the
faulty cell. Such alarms should be cleared.
Traffic
measurement
Causes of inter-RAT handover
failure
Incoming/outgoing inter-RAT handover
measurement
Signaling RSL signaling tracing data Check the causes of call drops.
DT data *.log (*.CELL) files or *.ant files Based on the drive test data, determine whether
interference or coverage problems exist.
Others Engineering parameter tables and
e-maps
Facilitate the checking of the geographical
information by the NASTAR tool.
2014-6-18 Huawei Technologies Proprietary Page 25 of 25