This document provides guidelines for LTE radio frequency (RF) network optimization. It describes the network optimization process including single site verification and RF optimization. Key optimization objects are defined such as reference signal received power (RSRP), signal to interference plus noise ratio (SINR), and handover success rate. Common coverage issues like weak coverage, coverage holes, lack of a dominant cell, and cross coverage are explained along with methods to resolve them. The document also outlines RF optimization preparations, methods, and troubleshooting techniques.
This document outlines Huawei's radio network planning and optimization work flow. It includes processes for pre-planning, network planning, optimization, and network acceptance. The network planning process includes RF surveys, planning concepts, and practical planning. Optimization includes drive test optimization, KPI optimization, and network monitoring. The document provides details on each stage of the process and refers to other documents for more specific guidelines. It is intended to standardize and improve the workflow for radio network planning.
The key performance indicators for measuring 3G cell performance include accessibility metrics like RRC success rate, RAB success rate, and CSSR. Retainability is measured by dropped call rates for speech, video, and packet switched connections. Mobility is measured by handover success rates between cells and between 3G and 2G networks. Factors that affect HSDPA throughput include downlink power, the number of downlink codes allocated for HSDPA, and transport channel capacity. Tuning parameters like increasing the number of HSDPA codes or changing the scheduling algorithm can improve HSDPA throughput.
TEMS tools are used at various stages of radio network design, rollout, operation and improvement. During the design and rollout phase, TEMS is used for network integration testing, initial tuning, and GPRS performance verification. In the operation and improvement phase, it is used for traditional optimization and network feature optimization. TEMS allows measurement of key performance indicators, analysis of issues like low signal strength, interference, handover problems and call setup failures. It helps identify root causes and evaluate potential solutions.
LTE uses various frequency bands and duplexing techniques to provide high-speed data and peak download speeds of up to 300 Mbps. It supports mobility of up to 350 km/h and uses advanced technologies like OFDM, SC-FDMA, MIMO and turbo coding to achieve low latency and high bandwidth. LTE specifications define channel bandwidths of 1.4, 3, 5, 10, 15 and 20 MHz with modulation schemes of QPSK, 16QAM and 64QAM.
This document discusses optimization of GSM networks through adjusting various network parameters. It covers topics such as single band optimization philosophy, the network optimization process, optimization phases, BSS optimization parameters like cell selection and reselection, power control, and handover control. Drive testing and analysis are also involved in the optimization process.
This document provides a troubleshooting guide for UMTS access KPI issues. It includes:
1. An overview of the UMTS access signaling flow and definitions of related performance statistics and KPIs.
2. A classification of RRC access failure root causes such as resource congestion, RF problems, and equipment alarms.
3. Guidance on analyzing access failure data and counters to diagnose issues related to causes like CE congestion, power limitations, or code shortages.
4. Recommended solutions for optimizing access performance issues related to resource congestion.
1) The document describes key performance indicators (KPIs) for measuring the performance of an LTE radio network. It discusses KPIs related to accessibility, retainability, mobility, and latency.
2) Accessibility KPIs measure aspects like call setup success rate, RRC setup success rate, and E-RAB setup success rate. Retainability KPIs measure call drop rate and call setup completion rate. Mobility KPIs measure handover success rates within LTE and between LTE and other technologies.
3) For each KPI, the document provides a definition, calculation formula, and description of which network events and counters are needed to measure the KPI. Baseline
Wcdma Radio Network Planning And OptimizationPengpeng Song
The document discusses WCDMA radio network planning and optimization, including key topics such as:
1) Fundamentals of WCDMA link budget analysis and radio interface protocol architecture.
2) Radio resource utilization techniques like power control, handover control, and congestion control.
3) Issues of coverage and capacity planning as well as enhancement methods.
4) The process of WCDMA radio network planning including dimensioning, detailed planning, and optimization aspects to address interference.
Wcdma dt analysis using TEMS InvestigationMichael Ofili
The document discusses drive test and call quality test procedures for analyzing mobile network coverage and service performance. It provides an introduction to the test tools used, including phones and data cards that support UMTS, HSDPA, HSUPA, EDGE, and GPRS technologies. Key metrics analyzed include signal strength, quality, throughput rates, call setup success, handover success, call drops, and delays. Issues examined include overshooting, pilot pollution, and missing neighbors. Potential solutions involve adjusting antenna parameters, modifying configuration settings, and optimizing base station placement and power levels.
The document discusses optimization of 3G radio networks, focusing on the RF Optimization phase. It describes the various stages of network optimization including single site verification, RF optimization of clusters of sites, parameter optimization testing, and ongoing reference route testing and analysis. The RF Optimization process involves preparing clusters and drive routes, analyzing data to identify issues, determining solutions such as antenna adjustments, implementing changes, and retesting. Analysis approaches discussed include examining cell dominance, coverage, interference, uplink coverage, pilot pollution, neighbor lists, soft handover performance, and drop calls.
The document discusses several topics related to LTE cell planning including:
1. The general LTE cell planning process includes information collection, pre-planning, detailed planning, and cell planning which focuses on frequency, tracking area (TA), physical cell ID (PCI), and physical random access channel (PRACH) planning.
2. There are several new frequency bands for LTE including 700MHz, AWS, 2.6GHz, and reusing existing GSM bands.
3. Topics like interference coordination (ICIC), TA planning to reduce signaling, PCI planning requirements, cyclic prefix impact on symbol energy, and PRACH parameters and configurations are covered.
The document describes traffic counter systems in RNCs (Radio Network Controllers) and cells in 3G WCDMA networks. It discusses key performance indicators for traffic, including Erlang load, throughput, number of radio bearers, and more. Counters are grouped by their measurement location (RNC or cell) and type (traffic, radio bearers, HSDPA, transmit power). The purpose is to understand and monitor traffic patterns and performance at different levels of the 3G network.
This document outlines key metrics and tests for a single cell functional test (SCFT). The SCFT checks:
1) Basic cell functionality like scrambling code identification, cell broadcast name, landline-mobile calls, and mobile-mobile calls between the same and other networks.
2) Radio channel quality metrics like BLER, EcNo, RSCP, and RSSI and whether values are within expected ranges.
3) Handover configurations and whether intra-site, inter-site, 3G-2G, and 2G-3G handovers occur as expected.
4) Data throughput tests including checking available data rates and latency via ping tests.
The document discusses various parameters used in LTE drive testing including:
- RSRP, RSRQ, SINR, RSSI, CQI, PCI, BLER, and throughput which provide information on signal strength, quality, and performance. Phone-based drive testing allows monitoring of these parameters and correlation with data performance. MIMO and handovers between LTE and other technologies can also be evaluated. Key metrics include coverage, capacity, and end-user experience.
This document discusses key performance indicators (KPIs) for evaluating 3G networks. It describes various KPIs for measuring accessibility, retainability, mobility, coverage, service integrity, availability, and traffic. Formulas for calculating several KPIs are provided. Troubleshooting methods and examples are given for accessibility, retainability, and mobility-related issues. Sample daily reports and the Gsmart optimization tool interface are also shown.
This document discusses WCDMA RF optimization processes, policies, and case studies. It describes the three steps of the WCDMA RF optimization process: single station check, base station group optimization, and whole network optimization. It then discusses common RF problems, analysis, and optimization policies for issues like call drops, discontinuity, and access failures. Finally, it presents five case studies of WCDMA network optimization including issues like handover problems, coverage gaps, high site interference, and neighbor cell list configuration errors.
3 g interview question & answer by telsol360Tel sol
3G (WCDMA) Interview Question and answer asked by Top recruiters like NSN global and Ericsson global.
Prepare yourself for the Interview by the help this Documents specially designed by Telsol360 technical team .
The document discusses drive test analysis for mobile networks. It describes the key elements of an effective drive test program including understanding network performance using call and data metrics. The drive test process involves defining test routes and clusters, collecting data, analyzing key performance indicators (KPIs) like call setup success rate and throughput, and troubleshooting issues. Defining test cases, KPIs, and categorizing failures is important for understanding genuine network problems versus measurement errors.
The document contains questions and answers related to GSM and LTE drive test parameters. It discusses key topics like reference signal receive power (RSRP), reference signal receive quality (RSRQ), signal to noise ratio (SINR), received signal strength indicator (RSSI), physical cell ID (PCI), channel quality indicator (CQI), block error rate (BLER), downlink and uplink throughput, and WCDMA/3G questions and answers related to link budget, TMA, processing gain, and calculating maximum number of users.
Lte drivetest guideline with genex probeRay KHASTUR
1. Drive testing involves collecting radio frequency data through a test device to evaluate network coverage and quality of service parameters.
2. Major LTE key performance indicators measured include accessibility, retainability, mobility, and integrity. Key parameters measured are RSRP, SINR, and throughput.
3. To perform an effective drive test, the tester must understand parameter definitions, avoid duplicate routes, analyze events like call drops, and strategically test throughput in stable conditions.
The Yo.Vi project aims to integrate victims and victim protection within restorative justice practices for youth offenders. It is funded by the EC and coordinated by the Italian Ministry of Justice. The project involves partners from 7 EU countries and includes national research, development of guidelines, workshops, and a final conference. The Yo.Vi website provides information on reports, guidelines, newsletters, and opportunities to join the stakeholder network.
Presentación sobre las alternativas de virtualizacion presentada en el curso de Arquitectura del Computaador en la UNIVERSIDAD NACIONAL TECNOLÓGICA DE LIMA SUR.
O documento descreve o projeto Yo.Vi, que promove modelos integradores de justiça restaurativa para vítimas e jovens. O projeto é financiado pela Comissão Europeia e coordenado pelo Ministério da Justiça Italiano. Ele envolve parceiros de sete países da UE e tem como objetivo apoiar a integração e proteção das vítimas no âmbito das práticas de justiça restaurativa no sistema de justiça juvenil.
Nas últimas décadas nas áreas de Compras, Logística, Materiais, Suprimentos e atualmente no conceito moderno chamado de Supply Chain, me deparei com muitos colegas, chefes, colaboradores e consultores que necessitam conhecer, aplicar metodologias e trabalhar com estratégias. Nos orçamentos e planejamentos anuais, trabalhando com implementações dos mesmos ou em treinamentos, alguns destes profissionais me confidenciaram dois tipos de problemas:
The document summarizes Cultivate's 2016 residency program. It provides important dates like the May 15 application deadline and July-December program dates. It describes program locations in Eastern and Southern Africa and the opportunities in areas like communications, media, and IT. The program aims to help residents work skillfully, think missionally, grow spiritually, and impact globally over the 6-month experience through placements based on their skills and immersion in international Christian communities.
This document discusses field insights from real-world deployments of multi-vendor heterogeneous networks. It summarizes deployment experiences in Russia and a major European city involving over 270 small cells from multiple vendors interconnected via X2 and managed by a third-party core network. Results showed over 99% mobility success rates and up to a 10x throughput improvement when optimizing hotspot deployment locations. Addressing deployment challenges involves leveraging an ecosystem of partners for site acquisition, backhaul, installation and maintenance.
Este documento presenta información sobre el planeamiento estratégico y los planes operativos en el contexto de un hospital. Define los planes operativos como documentos que enumeran los objetivos y directrices a corto plazo de una organización por un período de un año. Explica que los planes operativos se derivan de los planes estratégicos y directores. También define el planeamiento estratégico como un proceso para visionar el futuro de una organización y desarrollar las acciones para lograr esa visión. A continuación, presenta los objetivos, misión,
Ericsson important optimization parametersPagla Knight
The document lists important optimization parameters for Ericsson including parameters related to system configuration, capacity management, directed retry, handover, HSDPA/EUL, IRAT, and idle mode selection and reselection. It provides descriptions of over 50 parameters that control aspects such as power levels, admission limits, thresholds for cell reselection, and criteria for measurements.
The document provides an overview and analysis flow for optimizing the performance of a mobile network. It discusses various problems that can occur like low availability of control channels, congestion on signaling and traffic channels, and high drop call rates. For each problem, it lists probable causes and recommends actions to identify the issue and solutions to resolve it, such as adjusting configuration parameters, adding network capacity, or improving frequency planning. MML commands are also provided to check device logs, resources, and performance statistics for troubleshooting purposes.
Especificaciones tecnicas generales para lineas de alta tensionCarolina Díaz
Este documento presenta las especificaciones técnicas generales para líneas de alta tensión. Detalla los requisitos para materiales como cables conductores, de guardia, aisladores, soportes de madera, hormigón y acero, así como accesorios, empalmes y equipos de prueba. También cubre aspectos del diseño de proyectos de líneas como distancias de seguridad, cruces, disposición de cables y presentación de planos. Por último, describe los procedimientos de ejecución, pruebas y documentación requerida.
The document discusses using the Atoll radio planning software to design a UMTS mobile network to provide coverage for the town of Seville, Spain. Atoll allows modeling network traffic based on user profiles and services. It also incorporates detailed maps of Seville for terrain and land use data needed for radio propagation modeling and network optimization. The document defines user profiles for adolescents and young people with different expected usage patterns for voice, MMS, internet access, and video calling services.
This document provides quality guidelines and recommendations for Samsung's Small Cell Field Test (SCFT) process. It outlines objectives to ensure accurate SCFT validation and improve quality. Guidelines are provided for circles, central SCFT optimizers, and the WCC2 quality assurance team. Key points addressed include throughput thresholds, handling of KPI failures, drive route guidelines, escalation processes, and responsibilities of various roles. The overall goal is to minimize errors and re-drives to accelerate the WCC approval process.
The document discusses the need for new wireless technologies to support increasing demand for data and high-speed services. It notes that technologies need to focus on using more spectrum, improving spectral efficiency, employing smaller cell sizes like femtocells, and incentivizing off-peak traffic. The rest of the document provides details on how LTE wireless technology addresses these needs through technical specifications and network architecture, including the use of an Evolved Packet Core and separating the user and control planes.
UMTS ... is 3G technology and concepts. It introduced a new radio access network called UTRAN and a new air interface called WCDMA. The core network was initially based on GSM/GPRS but was expanded with new nodes. UMTS defined four quality of service classes and new protocols were introduced for the user plane and control plane in UTRAN and between network elements. Key concepts included serving and drift RNCs for soft handover, and SRNS relocation for changing the serving RNC.
This document provides an overview of VoLTE features and functions on various eNodeB types. It describes basic VoLTE functions such as speech codecs, radio bearer management, and admission control. It also covers enhanced features for capacity, coverage, quality, and power saving. Finally, it includes engineering guidelines for deploying and monitoring VoLTE performance.
The document provides information about conducting a Single Cell Functional Test (SCFT) procedure. It outlines the objectives of the SCFT, which are to understand how to perform the test and understand the workflow management system. It describes who should attend the training, including field engineers, drive test engineers, and area managers. The agenda covers topics like the SCFT process, preparations required, the drive test, using the testing tools, and important notes.
This document provides guidelines for optimizing LTE radio frequency (RF) networks during and after project implementation. It discusses the network and RF optimization process, including single site verification and RF optimization of clusters. Key RF optimization objects like coverage, signal quality, and handover success rate are examined. Methods for adjusting parameters like transmit power, antenna tilts and heights are provided to resolve issues like weak coverage, lack of a dominant cell, and cross coverage between sites. Drive testing and analyzing metrics like RSRP, SINR and handover rates are recommended for identifying problem areas.
This document provides guidelines for optimizing LTE radio frequency (RF) networks. It describes the network optimization process, including single site verification and RF optimization. RF optimization aims to control pilot pollution while optimizing signal coverage, handover success rates, and radio signal distribution. The document defines key performance indicators for LTE RF optimization including reference signal received power (RSRP), signal to interference plus noise ratio (SINR), and handover success rate. It also provides methods for adjusting parameters like antenna tilt, transmit power, and neighbor lists to troubleshoot issues related to coverage, signal quality, and handover rates.
The document introduces LTE network planning and RNP solutions. It discusses the flat LTE network architecture and protocols including OFDM and MIMO. LTE network planning includes coverage and capacity planning using link budget and capacity estimation. The RNP solution introduces tools for performance enhancement like interference avoidance and co-antenna analysis.
The document summarizes the key concepts in planning and deploying a 3G WCDMA mobile network. It describes the network architecture including nodes like RNC, Node B and interfaces. It also explains radio network planning phases and considerations like frequency planning, link budget calculations, coverage and capacity planning. The document discusses technologies like HSDPA that enhance data capabilities and presents LinkIT, a planning tool developed to understand network planning mathematics.
1.LTE Network Architecture
2.LTE Radio Interface Overview
3.E-UTRA Features and Interfaces
4.Radio Interface Techniques
5.FDD and TDD
6.Spectrum Usage in LTE
7.Radio and Network Identities
OFDM, OFDMA and SC-FDMA Basic Principles
1. OFDMA Principle
2.Signal generation and processing
3.Inter Symbol Interference
4.OFDM Problems
5.SC-FDMA
6.Frequency Hopping
7.Proposed use in LTE
8.Pros and Cons with OFDM and SC-FDMA
This third webinar discusses the fundamentals of LTE Carriers and how LTE mobiles communicate with the network including what factors affect performance.
Powerful business model for fixed wireless data using outdoor antennas - PaperAndre Fourie
Paper presented at the 2nd Africa Radio Comms Conference in Johannesburg - Nov 2015
By Andre Fourie
The revenue that can be generated by an LTE base station is influenced by the quality of the signal received by the customer premise equipment (CPE). Most CPE come with omni-directional indoor antennas, but have provision for the connection to external antennas.
Substituting the indoor antennas for directional outdoor antennas has a marked effect on the data transfer speeds of the network. There are two reasons for this. Firstly, outdoor antennas are physically larger than their indoor counterparts and thus have a higher gain. The increase in antenna gain translates directly to an increase in received signal strength. The second advantage is that the outdoor antenna sits in an environment that has much better propagating properties than the indoor antenna. Tests have shown that data speeds 3-5 times faster are possible using external antennas compared to indoor antennas.
It is shown, using a primitive financial model that fairly large financial gains can be made by equipping CPE devices with external antennas.
Rohit Choudhary is a RF engineer with over 7 years of experience in telecom network optimization. He has worked with various companies including Vodafone, Idea, Airtel, and Jio on 2G, 3G, and 4G network optimization projects in India. His responsibilities included drive testing, analyzing reports, identifying issues, optimizing sites, planning new sites, and achieving key performance indicators. He is proficient with various RF software tools and has skills in areas such as coverage optimization, interference management, neighbor planning, and handover tuning.
150154357 umts-multi-carrier-strategy-training-150514091047-lva1-app6892Walter Dono Miguel
Huawei provides strategies for multi-carrier networks including preferred camping and random camping. Preferred camping prioritizes certain carriers for idle mode camping and connections while random camping allows camping and connections on all carriers randomly. The strategies aim to balance considerations like system capacity, voice quality, and load balancing. Network operators can evaluate existing strategies using tools and adjust strategies based on key performance indicators to better meet their priorities such as capacity or coverage needs.
Huawei provides strategies for multi-carrier networks including preferred camping and random camping. Preferred camping prioritizes certain carriers for idle users and services while random camping allows users to camp on any carrier randomly. The document discusses pros and cons of each strategy and provides examples of analyzing network strategies using audit tools, adjusting strategies based on key performance indicators, and configuring parameters for mobility, load balancing, and carrier selection policies in multi-carrier networks.
Carrier aggregation allows LTE networks to aggregate multiple component carriers to increase bandwidth and peak data rates. It is a key technology in LTE-Advanced. Three carrier aggregation was standardized in Release 10 and improvements were made in Releases 11 and 12. Implementing carrier aggregation poses design challenges for user equipment due to requirements for complex transceiver architectures capable of simultaneously transmitting and receiving on multiple frequency bands, which can cause issues like intermodulation distortion. It also impacts higher layers with changes to RRC signaling and the addition of cross-carrier scheduling capabilities. Thorough testing is needed to validate performance under realistic radio frequency impairment conditions.
The document discusses key performance indicators (KPIs) for 2G and 3G networks such as call blocking, call drops, and handover success rates. It provides optimization strategies recommended by major telecom vendors like Ericsson, Huawei, and NSN to improve these KPIs by adjusting network parameters related to frequency reuse, power control, handover configurations, and radio resource management. The parameter optimizations are aimed at enhancing voice call performance for 2G networks while also balancing throughput, capacity, and radio quality between 2G and 3G networks to ensure a seamless transition between the radio access technologies.
LTE network planning includes coverage and capacity planning. Key aspects of LTE network planning covered in the document include the flat LTE network architecture, use of OFDM in the physical layer, and introduction of techniques like MIMO, ICIC, link budget analysis, and capacity estimation. The document also provides an overview of RNP solutions for interference avoidance, co-antenna analysis, and other performance enhancement features.
A collection of several vital configuration tips and tricks which are widely implemented across mid-size to large enterprise WLAN. Primary focus would be on Security as well as Performance characteristics of Aruba WLAN networks. Check out the webinar recording where this presentation was used.
https://community.arubanetworks.com/t5/Wireless-Access/Technical-Webinar-Recording-Slides-Aruba-controller-features/td-p/279274
Register for the upcoming webinars: https://community.arubanetworks.com/t5/Training-Certification-Career/EMEA-Airheads-Webinars-Jul-Dec-2017/td-p/271908
Lte tdd femto cell for usage of tv white spaceYoung Hwan Kim
This document discusses using TV white space spectrum and technologies like Super WiFi (802.11af), 802.22, and LTE-TDD to support wireless internet hotspots. It compares Super WiFi and LTE-TDD for supporting hotspots and outlines both the technical and business challenges of using LTE-TDD femtocells deployed on TV white space to provide wireless internet access, such as developing an O&M system, satisfying spectrum regulations, and finding partners and customers.
2 g and 3g kpi improvement by parameter optimization (nsn, ericsson, huawei) ...Jean de la Sagesse
The document discusses key performance indicators (KPIs) for 2G and 3G networks and how top telecom vendors like Ericsson, Huawei, and NSN optimize parameters to improve these KPIs. It outlines techniques for reducing TCH blocking, SD blocking, TCH drop, HOSR, TASR, SD drop, and improving paging success rate through actions like changing configuration parameters, enabling features, addressing hardware issues, and optimizing cells physically. The optimization of these parameters can help maintain balance between network throughput, capacity and radio quality while ensuring a seamless transition between 2G and 3G.
A DAS is a network of antennas connected by cable that provides wireless coverage inside buildings. DAS are needed for public safety to improve coverage and reliability for first responders. The benefits of a public safety DAS include 95% building coverage, high quality of service, and improved reliability. Proper DAS design is important to ensure adequate coverage levels are met based on standards from NFPA and IFC. Components like filtered repeaters, backup power, and antennas supporting all public safety frequencies are important. New FCC rules require registration of bi-directional amplifiers used on public safety networks.
This document discusses optimization of radio parameters in WCDMA networks. It describes the process of parameter optimization including collecting configuration, signaling, drive test and statistics data. It then lists common radio parameter optimization cases such as coverage, handover, call drop rates, access control and signal quality. Specific cases covered in more detail include increasing PCPICH power to improve coverage, increasing the maximum DL power of AMR to reduce call drops, increasing FACH power to improve RRC setup success rates, and optimizing the T300 timer to further improve RRC success rates.
Similar to Hwlte rf-optimization-guide-140704020836-phpapp02 (20)
The document provides an overview of telecommunication networks and their components. It discusses:
1) The major components of telecommunication networks including transmission facilities, local loops, interoffice facilities, switching systems, and customer premise equipment.
2) How transmission facilities such as local loops and trunks connect different parts of the network and carry traffic.
3) Analog and digital transmission methods, including frequency division multiplexing, time division multiplexing, and pulse code modulation to convert analog signals to digital formats.
This document provides information and instructions for performing drivetest, which is a process of collecting network performance data using testing equipment while driving along predetermined routes. It discusses what drivetest is, differences between tuning and optimization, purposes of drivetest, types of drivetest, tools used for drivetest, and best practices for performing drivetest. The document also provides screenshots and exercises for setting up the TEMS Investigation software for drivetest data collection and configuration.
This document provides an overview of analyzing SDCCH drop rate as a key performance indicator. It discusses the causes of SDCCH drops, investigation procedures, and troubleshooting techniques. Tools described include Business Objects, ZXG10 OMCR, TEMS Investigation, and MCOM 4.2. The technical procedure outlines analyzing SDCCH availability, causes, alarms, measurements, parameters, and drive testing. Examples demonstrate addressing hardware problems, interference, transmission issues, and parameter changes.
This document outlines the WCDMA physical layer design. It discusses the WCDMA network architecture and physical layer in detail. Specifically, it describes the uplink and downlink physical channels, transport channels, logical channels, spreading techniques, channelization codes, scrambling codes, and frame structure used in WCDMA. It provides information on uplink and downlink dedicated and common physical channels, and the various coding, modulation, and multiplexing schemes used in the WCDMA physical layer.
This document describes a training course on analyzing handover issues in cellular networks. It covers measurement points for intra-BSC and inter-BSC handovers, how handover data is processed, common types and causes of handover problems, and two case studies of handover issues and their resolution. The goal is for readers to understand handover principles, analyze problems, and solve issues.
This document provides an agenda and procedures for conducting cluster optimization tests. It describes drive routes that cover all sectors of each base station in the cluster. Key tests include FTP uplink/downlink calls, VoLTE calls, and checks of coverage, mobility, accessibility and voice quality. The objectives are to validate RF design, handover performance, retainability, and identify worst areas for improvement through two drive tests and analysis of call logs and KPIs. Attendees should be RF and drive test engineers familiar with the XCAL tool and SCFT procedures.
This document discusses a case study of call drops occurring in the second sector of base station C. Through analyzing traffic statistics and conducting drive tests, it was found that interference was the cause of the high call drop rate. Specifically, a broadband repeater transmitting nearby digital signals was amplifying interference into the sector. Lowering the power of the repeater resolved the call drop issue.
This document discusses WCDMA channels at different levels including logical channels, transport channels, and physical channels. It provides details on:
- Logical channels describe the type of information transferred and include control and traffic channels.
- Transport channels describe how logical channels are transferred over the interface and include dedicated and common channels.
- Physical channels provide the transmission medium and are defined by specific codes. They include channels like DPDCH, DPCCH, PDSCH, PRACH, and CPICH.
- The document also discusses the radio frame structure in WCDMA and details on different physical channel types and their characteristics.
This document provides an overview of Huawei's UMTS O&M system and guidance on planning and configuring the O&M network. It introduces the key components of the UMTS network and O&M system, including the M2000 platform, CN-PS devices like SGSN9810, CN-CS devices such as MSOFTX3000, and RAN devices including BTS3812. It also covers establishing the O&M network through various IP bearer modes, applying security solutions, and following best practices for O&M network planning.
This document is the confidential property of NORTEL MATRA CELLULAR and provides engineering guidelines for dimensioning the Abis interface between BTS and BSC in a GSM network. It includes guidelines for dimensioning signaling links, transmission channels, and redundancy requirements. The document has undergone several revisions to incorporate comments and modifications.
This document compares the key RF radio parameters of 2G, 3G, and 4G cellular networks, including normal value ranges for RxLevel, RxQual, C/I metrics in 2G, RSRP, RSRQ in 3G/4G, and SQI, SNR, CQI metrics. It also provides a brief explanation that RxLevel depends on factors like BTS transmission power, antenna gain, and path loss.
Literature Reivew of Student Center DesignPriyankaKarn3
It was back in 2020, during the COVID-19 lockdown Period when we were introduced to an Online learning system and had to carry out our Design studio work. The students of the Institute of Engineering, Purwanchal Campus, Dharan did the literature study and research. The team was of Prakash Roka Magar, Priyanka Karn (me), Riwaz Upreti, Sandip Seth, and Ujjwal Dev from the Department of Architecture. It was just a scratch draft made out of the initial phase of study just after the topic was introduced. It was one of the best teams I had worked with, shared lots of memories, and learned a lot.
A brief introduction to quadcopter (drone) working. It provides an overview of flight stability, dynamics, general control system block diagram, and the electronic hardware.
Exploring Deep Learning Models for Image Recognition: A Comparative Reviewsipij
Image recognition, which comes under Artificial Intelligence (AI) is a critical aspect of computer vision,
enabling computers or other computing devices to identify and categorize objects within images. Among
numerous fields of life, food processing is an important area, in which image processing plays a vital role,
both for producers and consumers. This study focuses on the binary classification of strawberries, where
images are sorted into one of two categories. We Utilized a dataset of strawberry images for this study; we
aim to determine the effectiveness of different models in identifying whether an image contains
strawberries. This research has practical applications in fields such as agriculture and quality control. We
compared various popular deep learning models, including MobileNetV2, Convolutional Neural Networks
(CNN), and DenseNet121, for binary classification of strawberry images. The accuracy achieved by
MobileNetV2 is 96.7%, CNN is 99.8%, and DenseNet121 is 93.6%. Through rigorous testing and analysis,
our results demonstrate that CNN outperforms the other models in this task. In the future, the deep
learning models can be evaluated on a richer and larger number of images (datasets) for better/improved
results.
In May 2024, globally renowned natural diamond crafting company Shree Ramkrishna Exports Pvt. Ltd. (SRK) became the first company in the world to achieve GNFZ’s final net zero certification for existing buildings, for its two two flagship crafting facilities SRK House and SRK Empire. Initially targeting 2030 to reach net zero, SRK joined forces with the Global Network for Zero (GNFZ) to accelerate its target to 2024 — a trailblazing achievement toward emissions elimination.
A vernier caliper is a precision instrument used to measure dimensions with high accuracy. It can measure internal and external dimensions, as well as depths.
Here is a detailed description of its parts and how to use it.
Response & Safe AI at Summer School of AI at IIITHIIIT Hyderabad
Talk covering Guardrails , Jailbreak, What is an alignment problem? RLHF, EU AI Act, Machine & Graph unlearning, Bias, Inconsistency, Probing, Interpretability, Bias
2. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 2
Change History
Date Version Description Author
0.5 LTE RNPS
1.0 LTE RNPS
3. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 3
Preface
To meet customers' requirements for high-quality networks, LTE trial
networks must be optimized during and after project implementation. Radio
frequency (RF) optimization is necessary in the entire optimization process.
This document provides guidelines on network optimization for network
planning and optimization personnel.
5. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 5
Network Optimization Flowchart
New site
on air
Single site
verification
Are clusters
ready?
RF optimization
Service test and
parameter optimization
Are KPI
requirements met?
No Yes Yes
No
End
6. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 6
Network Optimization Process
Single site verification
Single site verification, the first phase of network optimization, involves
function verification at each new site. Single site verification aims to
ensure that each site is properly installed and that parameters are
correctly configured.
RF optimization
RF (or cluster) optimization starts after all sites in a planned area are
installed and verified. RF optimization aims to control pilot pollution
while optimizing signal coverage, increase handover success rates, and
ensure normal distribution of radio signals before parameter
optimization. RF optimization involves optimization and adjustment of
antenna system hardware and neighbor lists. The first RF optimization
test must traverse all cells in an area to rectify hardware faults.
7. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 7
RF Optimization Flowchart
Data collection:
Drive test
Indoor measurement
eNodeB configuration data
Problem analysis:
Coverage problem analysis
Handover problem analysis
Adjustment & implementation:
Engineering parameter
adjustment
Neighboring cell parameter
adjustment
Do the RF KPIs meet the KPI
requirements?
Y
End
N
Start
Test preparations:
Establish optimization objectives
Partition clusters
Determine test routes
Prepare tools and materials
8. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 8
Preparations for RF Optimization
Checklist
Network plan, network structure diagram, site distribution, site
information, and engineering parameters
Drive test results (such as service drop points and handover
failure points) in the current area
Reference signal received power (RSRP) coverage diagram
Signal to interference plus noise ratio (SINR) distribution diagram
Measured handover success rates
Areas to be optimized can be determined by comparing the
distribution of RSRPs, SINRs, and handover success rates with
the optimization baseline.
9. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 9
Network Optimization Methods
RF optimization involves adjustment of azimuths, tilts, antenna height, eNodeB transmit
power, feature algorithms, and performance parameters. Optimization methods in different
standards are similar, but each standard has its own measurement definition.
Network
Optimization
Azimuth AdjustmentTilt Adjustment
Feature Configuration
Reselection and
Handover
Parameter Adjustment
Power Adjustment
Antenna Height
11. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 11
LTE RF Optimization Objects and
Target Baseline
What are
differences
between LTE
and 3G
optimization?
Text
RSRP
SINR
Handover
success rate
How are
these
counters
defined?
LTE
optimization
objects
12. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 12
RSRP
Note: Different from GSM or TD-SCDMA systems, TD-LTE systems have multiple subcarriers multiplexed.
Therefore, the measured pilot signal strength is the RSRP of a single subcarrier (15 kHz) not the total
bandwidth power of the frequency.
The RSRPs near a cell, in the middle of a cell, and at the edge of a cell are determined based on the
distribution of signals on the entire network. Generally, the RSRP near a cell is -85 dBm, the RSRP in the
middle of a cell is -95 dBm, and the RSRP at the edge of a cell is -105 dBm.
Currently, the minimum RSRP for UEs to camp on a cell is -120 dBm.
Empirical RSRP at the edge of a cell:
The RSRP is greater than -110 dBm in 99% areas at the TD-LTE site in Norway.
The RSRP is greater than -110 dBm in 98.09% areas in the Huayang field in Chengdu.
Reference signal received power (RSRP), is determined for a
considered cell as the linear average over the power
contributions (in [W]) of the resource elements that carry cell-
specific reference signals within the considered measurement
frequency bandwidth.
3GPP
definition
13. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 13
SINR
The SINR is not specifically defined in 3GPP specifications. A common formula is as
follows:
SINR = S/(I + N)
S: indicates the power of measured usable signals. Reference signals (RS) and physical
downlink shared channels (PDSCHs) are mainly involved.
I: indicates the power of measured signals or channel interference signals from other
cells in the current system and from inter-RAT cells.
N: indicates background noise, which is related to measurement bandwidths and receiver
noise coefficients.
Empirical SINR at the edge of a cell:
The SINR is greater than -3 dB in 99% areas in Norway.
The SINR is greater than -3 dB in 99.25% areas in the Huayang field in Chengdu.
14. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 14
Handover Success Rate
According to the signaling process in 3GPP TS 36.331,
eNodeB statistics
(1) Handover success rate = Number of handovers/Number of handover
attempts x 100%
(2) Number of handover attempts: indicates the number of eNodeB-
transmitted RRCConnectionReconfiguration messages for handovers.
(3) Number of handovers: indicates the number of eNodeB-received
RRCConnectionReconfigurationComplete messages for handovers.
Handover success rate
The handover success rate is greater than 97% at the TD-LTE site in
Norway.
The handover success rate is 100% in the Huayang field in Chengdu.
15. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 15
Power Adjustment Method
Service power configuration (calculating PDSCH power based
on RS power)
RS power PA and PB are delivered using RRC signaling. For
two antennas, PA is ρA and ρB is calculated based on the right
table. PDSCH power is calculated based on PA and PB.
Currently, it is recommended that PB be set to 1 dB and PA be
set to -3 dB. That is, the pilot power for symbols including pilot
symbols accounts for 1/3. This setting optimizes network
performance and ensures that the pilot power for Type A and
Type B symbols is equivalent to the service channel power. In
scenarios with special requirements, for example, in rural
scenarios requiring low edge rates, PB can be set to 2 or 3 dB to
enhance coverage.
Subcarriers share the transmit power of an eNodeB, and therefore the transmit power
of each subcarrier depends on the configured system bandwidth (such as 5 MHz and 10
MHz). A larger bandwidth will result in lower power of each subcarrier. LTE uses PA and
PB parameters to adjust power.
ρA: indicates the ratio of the data subcarrier power of OFDM symbols excluding pilot
symbols to the pilot subcarrier power.
ρB: indicates the ratio of the data subcarrier power of OFDM symbols including pilot
symbols to the pilot subcarrier power.
Definitions in
3GPP
specifications
Control channels
Power of PDCCHs, PHICHs, PCFICHs,
PBCHs, primary synchronization channels,
and secondary synchronization channels is
set using an offset from RS power.
17. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 17
Classification of Coverage Problems
(RSRP is mainly involved)
Weak coverage and
coverage holes Cross coverage
Imbalance between
uplink and downlink
Lack of a
dominant cell
Continuous
coverage must be
ensured.
The actual
coverage must be
consistent with the
planned one to
prevent service
drops caused by
isolated islands
during handovers.
Uplink and
downlink losses
must be balanced
to resolve uplink
and downlink
coverage
problems.
Each cell on a
network must
have a dominant
coverage area to
prevent frequent
reselections or
handovers
caused by signal
changes.
18. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 18
Factors Affecting Coverage
1
Downlink:
•Equivalent isotropic
radiated power (EIRP)
•Total transmit power
•Combining loss
•Path loss (PL)
•Frequency band
•Distance between a receive
point and an eNodeB
•Scenarios (urban and
suburban areas) and terrains
(plains, mountains, and hills)
of electric wave propagation
•Antenna gain
•Antenna height
•Antenna parameters
(antenna pattern)
•Antenna tilt
•Antenna azimuth
2
Uplink:
•eNodeB receiver sensitivity
•Antenna diversity gain
•UE transmit power
•Propagation loss of uplink
radio signals
•Impact of tower-mounted
amplifiers (TMAs) on uplink
19. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 19
Weak Coverage and Coverage Holes
The signal quality in cells is poorer than the optimization baseline in an area.
As a result, UEs cannot be registered with the network or accessed services
cannot meet QoS requirements.
If there is no network coverage or coverage levels are excessively low in an area, the
area is called a weak coverage area. The receive level of a UE is less than its
minimum access level (RXLEV_ACCESS_MIN) because downlink receive levels in a
weak coverage area are unstable. In this situation, the UE is disconnected from the
network. After entering a weak coverage area, UEs in connected mode cannot be
handed over to a high-level cell, and even service drops occur because of low levels
and signal quality.
Weak
coverage
Coverage holes
20. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 20
Resolving Weak Coverage Problems
Analyze geographical
environments and check the
receive levels of adjacent
eNodeBs.
Analyze the EIRP of each
sector based on parameter
configurations and ensure
EIRPs can reach maximum
values if possible.
Increase pilot power.
Adjust antenna azimuths and
tilts, increase antenna height,
and use high-gain antennas.
Deploy new eNodeBs if
coverage hole problems
cannot be resolved by
adjusting antennas.
Increase coverage by
adjacent eNodeBs to achieve
large coverage overlapping
between two eNodeBs and
ensure a moderate handover
area.
Note: Increasing coverage
may lead to co-channel and
adjacent-channel
interference.
Use RRUs, indoor
distribution systems, leaky
feeders, and directional
antennas to resolve the
problem with blind spots in
elevator shafts, tunnels,
underground garages or
basements, and high
buildings.
Analyze the impact of
scenarios and terrains on
coverage.
21. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 21
Case: Searching for a Weak Coverage Area by
Using a Scanner or Performing Drive Tests on
UEs
Weak
coverage
area
Perform drive tests in zero-
load environments to obtain
the distribution of signals on
test routes. Then, find a
weak coverage area based
on the distribution, as
shown in the figure.
Adjust RF parameters of the
eNodeB covering the area.
22. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 22
Lack of a Dominant Cell
In an area without a dominant cell, the receive level of the serving cell is similar to the
receive levels of its neighboring cells and the receive levels of downlink signals between
different cells are close to cell reselection thresholds. Receive levels in an area without a
dominant cell are also unsatisfactory. The SINR of the serving cell becomes unstable
because of frequency reuse, and even receive quality becomes unsatisfactory. In this
situation, a dominant cell is frequently reselected and changed in idle mode. As a result,
frequent handovers or service drops occur on UEs in connected mode because of poor
signal quality. An area without a dominant cell can also be regarded as a weak coverage
area.
Lack of a
dominant
cell
23. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 23
Resolving Problems with Lack of a
Dominant Cell
…
Adjust engineering
parameters of a cell that can
optimally cover the area as
required.
Determine cells covering an
area without a dominant cell
during network planning, and
adjust antenna tilts and
azimuths to increase coverage
by a cell with strong signals
and decrease coverage of
other cells with weak signals.
24. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 24
Symptom
UEs frequently perform cell reselections
or handovers between identical cells.
Analysis
Analysis can be based on signaling
procedures and PCI distribution.
According to PCI distribution shown in
the figure, PCIs alternate in two or more
colors if there is no dominant cell.
Solution
According to the coverage plan, cell 337
is a dominant cell covering the area and cell
49 also has strong signals. To ensure
handovers between cells 337 and 49 at
crossroads, increase tilts in cell 49.
1.PCI distribution in cluster xx
Lack of a
dominant
cell
Case: Searching for an Area
Without a Dominant Cell
25. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 25
Cross Coverage
Cross coverage means that the coverage scope of an eNodeB exceeds the planned one and
generates discontinuous dominant areas in the coverage scope of other eNodeBs. For
example, if the height of a site is much higher than the average height of surrounding
buildings, its transmit signals propagate far along hills or roads and form dominant
coverage in the coverage scope of other eNodeBs. This is an “island” phenomenon. If a call
is connected to an island that is far away from an eNodeB but is still served by the eNodeB,
and cells around the island are not configured as neighboring cells of the current cell when
cell handover parameters are configured, call drops may occur immediately once UEs leave
the island. If neighboring cells are configured but the island is excessively small, call drops
may also occur because UEs are not promptly handed over. In addition, cross coverage
occurs on two sides of a bay because a short distance between the two sides. Therefore,
eNodeBs on two sides of a bay must be specifically designed.
Cross
coverage
26. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 26
Resolving Cross Coverage Problems
…
Adjust antenna tilts or
replace antennas with large-tilt
antennas while ensuring
proper antenna azimuths. Tilt
adjustment is the most
effective approach to control
coverage. Tilts are classified
into electrical tilts and
mechanical tilts. Electrical tilts
are preferentially adjusted if
possible.
Adjust antenna azimuths
properly so that the direction
of the main lobe slightly
obliques from the direction of
a street. This reduces
excessively far coverage by
electric waves because of
reflection from buildings on
two sides of the street.
Decrease the antenna
height for a high site.
Decrease transmit power of
carriers when cell
performance is not affected.
27. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 27
Case: Cross Coverage Caused
by Improper Tilt Settings
Symptom
As shown in the upper right figure, cross
coverage occurs in a cell whose PCI is
288. Therefore, the cell interferes with
other cells, which increases the
probability of service drops.
Analysis
The most possible cause for cross
coverage is excessively antenna height
or improper tilt settings. According to a
check on the current engineering
parameter settings, the tilt is set to an
excessively small value. Therefore, it is
recommended that the tilt be increased.
Solution
Adjust the tilt of cell 288 from 3 to 6. As
shown in the lower right figure, cross
coverage of cell 288 is significantly
reduced after the tilt is adjusted.
28. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 28
Case: Inverse Connections Involved
in the Antenna System
Symptom
The RSRPs of cells 0 and 2 at the Expo Village site are low and high respectively in
the red area shown in the figure. The signal quality of cells 0 and 2 is satisfactory in
the areas covered by cells 2 and 0 respectively.
Analysis
After installation and commissioning are complete, the RSRP in the direction of the
main lobe in cell 0 is low. After cell 0 is disabled and cell 2 is enabled, the RSRP in cell
2 is normal and the SINR is higher than that tested in cell 0. Therefore, this problem
may occur because the antenna systems in the two cells are connected inversely.
Test results are as expected after optical fibers on the baseband board are swapped.
Solution
Swap optical fibers on the baseband board or adjust feeders and antennas properly. It
is recommended that optical fibers on the baseband board be swapped because this
operation can be performed in the equipment room.
Suggestions
Network planning personnel must participate in installation. Alternatively, customer
service personnel have detailed network planning materials and strictly supervise
project constructors for installation. After installation is complete, labels must be
attached and installation materials must be filed.
29. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 29
Imbalance Between Uplink and
DownlinkWhen UE transmit power is less than eNodeB transmit power, UEs in idle mode may receive
eNodeB signals and successfully register in cells. However, the eNodeB cannot receive
uplink signals because of limited power when UEs perform random access or upload data.
In this situation, the uplink coverage distance is less than the downlink coverage distance.
Imbalance between uplink and downlink involves limited uplink or downlink coverage. In
limited uplink coverage, UE transmit power reaches its maximum but still cannot meet the
requirement for uplink BLERs. In limited downlink coverage, the downlink DCH transmit
code power reaches its maximum but still cannot meet the requirement for the downlink
BLER. Imbalance between uplink and downlink leads to service drops. The most common
cause is limited uplink coverage.
Imbalance
between
uplink and
downlink
Uplink coverage area
Downlink coverage area
coverage area
30. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 30
Resolving Problems with Imbalance
Between Uplink and Downlink
…
If no performance data is available for
RF optimization, trace a single user in the
OMC equipment room to obtain uplink
measurement reports on the Uu interface,
and then analyze the measurement
reports and drive test files.
If performance data is available, check
each carrier in each cell for imbalance
between uplink and downlink based on
uplink and downlink balance
measurements.
If uplink interference leads to imbalance
between uplink and downlink, monitor
eNodeB alarms to check for interference.
Check whether equipment works properly
and whether alarms are generated if
imbalance between uplink and downlink is
caused by other factors, for example, uplink
and downlink gains of repeaters and trunk
amplifiers are set incorrectly, the antenna
system for receive diversity is faulty when
reception and transmission are separated,
or power amplifiers are faulty. If equipment
works properly or alarms are generated,
take measures such as replacement,
isolation, and adjustment.
32. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 32
Signal Quality (SINR is mainly
involved)
① Frequency
plan
③ Site
selection
④ Antenna
height
⑤ Antenna
azimuths
⑥ Antenna tilts
② Cell layout
33. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 33
Resolving Signal Quality Problems
Caused by Improper Parameter Settings
Change and optimize frequencies based on drive test and
performance measurement data.
Optimizing
frequencies
Adjust antenna azimuths and tilts to change the distribution of signals in an
interfered area by increasing the level of a dominant sector and decreasing levels of
other sectors.
Adjusting the
antenna
system
Increase power of a cell and decrease power of other cells to form a dominant
cell.
Decrease RS power to reduce coverage if the antenna pattern is distorted because
of a large antenna tilt.
Power adjustment and antenna system adjustment can be used together.
Adding
dominant
coverage
Adjusting
power
34. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 34
Case: Adjusting Antenna Azimuths and Tilts
to Reduce Interference
Symptom
Cross coverage occurs at sites 1, 2, 3, 7, 8, 9, 10, 11, and 12, and co-channel interference occurs
in many areas.
Analysis
According to the analysis of engineering parameters and drive test data, cell density is large in
coverage areas. Coverage by each cell can be reduced by adjusting antenna azimuths and tilts.
Solution
Change the tilt in cell 28 from 2 degrees to 4 degrees so that the direction points to a
demonstration route. Change the tilt in cell 33 from 3 degrees to 6 degrees so that the direction
points to the Wanke Pavilion. Change the tilt in cells 50 and 51 from 3 degrees to 6 degrees so
that the direction points to the Communication Pavilion. Decrease the transmit power in cell 33 by
3 dB to reduce its interference to overhead footpaths near China Pavilion.
SINR before optimization in Puxi SINR after optimization in Puxi
Poor signal
quality before
optimization
35. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 35
Case: Changing PCIs of Intra-frequency Cells
to Reduce Interference Symptom
Near Japan Pavilion, UEs access a cell whose PCI is 3 and SINRs are low. UEs are about 200 m away from the
eNodeB. This problem may be caused by co-channel interference.
Analysis
This problem is not caused by co-channel interference because no neighboring cell has the same frequency as the
current cell. Cell 6 interferes with cell 3. SINRs increase after cell 6 is disabled. In theory, staggered PCIs can
reduce interference.
Solution
Change PCI 6 to PCI 8. Test results show that SINRs increase by about 10 dB.
SINR when cell 6 is enabled SINR when cell 6 is disabled SINR when PCI 6 is changed to PCI 8
36. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 36
Case: Handover Failure Caused by
Severe Interference
Symptom
During a test, handovers from PCI 281 to PCI 279 fail.
Analysis
Cell 281 is a source cell and is interfered by cells 279 and 178. Delivered handover
commands always fail and cannot be received correctly by UEs. Cell 279 is a target cell
for handover, and its coverage is not adjusted preferentially because the signal strength
in the handover area can ensure signal quality after handovers. Therefore, cell 178 must
be adjusted to reduce its interference to cell 281.
Solution
Adjust antenna tilts to decrease coverage by cell 178.
38. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 38
Analysis of Handover Success Rate
Problems
Neighboring cell optimization must be performed to ensure that UEs in idle or
connected mode can promptly perform reselection to or be handed over to
optimal serving cells. This helps achieve continuous coverage. In addition,
problems with delay, ping-pong, and non-logical handovers can be resolved by
optimizing coverage, interference, and handover parameters.
Poor handovers
Handover validity
1. Neighboring cell validity
2. Average receive level for
handovers
3. Average receive quality for
handovers
4. Ratio of the number of handovers
to the number of calls
5. Measurements on neighboring cell
handovers not defined
Interference
1. Uplink interference bands
2. Receive level and quality of
carriers
3. Number of handovers
because of poor uplink and
downlink quality
4. Average receive level and
power level for handovers
Coverage
1. Cross coverage
2. Imbalance between uplink and
downlink
3. Receive level measurements
4. Receive quality measurements
5. Receive levels of neighboring cells
6. Average level and TA when
service drops occur
39. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 39
Handover Problem Analysis
Checking handover validity
Obtain source and target cells using drive test software and then check whether handovers are
performed between two cells that are geographically far using Mapinfo.
Checking interference
Check interference in both source and target cells because handover failures may be caused
by uplink or downlink interference.
Checking coverage
Check source and target cells for cross coverage, imbalance between uplink and downlink, and
carrier-level receive quality and level.
Check contents
Check handovers based on RSRPs measured in UE drive tests.
1. Verify that RSRPs in the expected source and target cells are maximum.
2. Verify that the absolute RSRPs in the source and target cells are reasonable at a
handover point. In other words, handovers are not allowed if signal quality is excessively
poor. Specific RSRPs are determined based on the entire RSRPs on a network.
40. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 40
Case: Service Drops Caused by Missing
Neighboring Cell Configuration
Symptom
As shown in the upper right figure, a
UE sends multiple measurement
reports but is not handed over,
which may be caused by missing
neighboring cell configuration.
Analysis
According to measurement reports,
the UE sends an A3 report of cell
64. However, the
RRCConnectionReconfiguration
message in the lower right figure
shows that the current cell is cell
278 (the first cell) and cell 64 is not
included in the message. This
indicates that cells 278 and 64 are
not configured as neighboring cells.
Neighboring cell configuration on
live networks can be checked for
further confirmation.
Solution
Configure cells 278 and 64 as
neighboring cells.
41. HUAWEI TECHNOLOGIES CO., LTD. Huawei Confidential Page 41
Summary
RF optimization involves adjustment of neighboring cell lists and engineering parameters.
Most coverage and interference problems can be resolved by taking the following measures
(sorted in descending order by priority):
Adjusting antenna tilts
Adjusting antenna azimuths
Adjusting antenna height
Adjusting antenna position
Adjusting antenna types
Adding TMAs
Adjusting site position
Adding sites or RRUs
This document describes what are involved in the RF optimization phase of network optimization. RF optimization
focuses on improvement of signal distribution and provides a good radio signal environment for subsequent
service parameter optimization. RF optimization mainly use drive tests, which can be supplemented by other tests.
RF optimization focuses on coverage and handover problems, which can be supplemented by other problems. RF
optimization aims to resolve handover, service drop, access, and interference problems caused by these
problems. Engineering parameters and neighboring cell lists are adjusted in the RF optimization phase, while cell
parameters are adjusted in the parameter optimization phase.