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This document contains confidential and proprietary information of Mentum S.A. This document contains confidential and proprietary information of Mentum S.A. and may not be copied, transmitted, stored in a retrieval system, or reproduced in and may not be copied, transmitted, stored in a retrieval system, or reproduced in any format or media, in whole or in part, without the prior written consent of any format or media, in whole or in part, without the prior written consent of Mentum S.A. Information contained in this document supersedes that found in any Mentum S.A. Information contained in this document supersedes that found in any previous manuals, guides, specifications data sheets, or other information that may previous manuals, guides, specifications data sheets, or other information that may have been provided or made available to the

have been provided or made available to the useruser. This document is provided for. This document is provided for informational purposes only, and Mentum S.A. does not warrant

informational purposes only, and Mentum S.A. does not warrant or guarantee theor guarantee the accuracy

accuracy, adequacy, quality, adequacy, quality, validity, completeness or suitability , validity, completeness or suitability for any for any purpose thepurpose the information contained in this document. Mentum S.A. may update, improve, and information contained in this document. Mentum S.A. may update, improve, and enhance this document and the products to which it relates at any time without enhance this document and the products to which it relates at any time without prior notice to the

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Trademark rademark AcknowledgementAcknowledgement

Mentum and Mentum CellPlanner are registered trademarks owned by Mentum Mentum and Mentum CellPlanner are registered trademarks owned by Mentum S.A. TEMS is a registered trademark of As

S.A. TEMS is a registered trademark of Ascom Network Tcom Network Testing AB. This documentesting AB. This document may contain other trademarks, trade names, or service marks of other

may contain other trademarks, trade names, or service marks of other organizations, each of which is

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This document contains confidential and proprietary information of Mentum S.A. This document contains confidential and proprietary information of Mentum S.A. and may not be copied, transmitted, stored in a retrieval system, or reproduced in and may not be copied, transmitted, stored in a retrieval system, or reproduced in any format or media, in whole or in part, without the prior written consent of any format or media, in whole or in part, without the prior written consent of Mentum S.A. Information contained in this document supersedes that found in any Mentum S.A. Information contained in this document supersedes that found in any previous manuals, guides, specifications data sheets, or other information that may previous manuals, guides, specifications data sheets, or other information that may have been provided or made available to the

have been provided or made available to the useruser. This document is provided for. This document is provided for informational purposes only, and Mentum S.A. does not warrant

informational purposes only, and Mentum S.A. does not warrant or guarantee theor guarantee the accuracy

accuracy, adequacy, quality, adequacy, quality, validity, completeness or suitability , validity, completeness or suitability for any for any purpose thepurpose the information contained in this document. Mentum S.A. may update, improve, and information contained in this document. Mentum S.A. may update, improve, and enhance this document and the products to which it relates at any time without enhance this document and the products to which it relates at any time without prior notice to the

prior notice to the useruser. MENTUM S.A. M. MENTUM S.A. MAKES NO WARRANTIES, EXPRESSED ORAKES NO WARRANTIES, EXPRESSED OR IMPLIED, INCLUDING,

IMPLIED, INCLUDING, WITHOUT LIMITAWITHOUT LIMITATION, THOSE OF TION, THOSE OF MERCHANTABILITY ANDMERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THIS DOCU

FITNESS FOR A PARTICULAR PURPOSE, WITH RESPECT TO THIS DOCU MENT OR THEMENT OR THE

INFORMATION CONTAINED HEREIN. INFORMATION CONTAINED HEREIN.

T

Trademark rademark AcknowledgementAcknowledgement

Mentum and Mentum CellPlanner are registered trademarks owned by Mentum Mentum and Mentum CellPlanner are registered trademarks owned by Mentum S.A. TEMS is a registered trademark of As

S.A. TEMS is a registered trademark of Ascom Network Tcom Network Testing AB. This documentesting AB. This document may contain other trademarks, trade names, or service marks of other

may contain other trademarks, trade names, or service marks of other organizations, each of which is

organizations, each of which is the property of its respective owner.the property of its respective owner.

Last updated October 14, 2010 Last updated October 14, 2010

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Navigation

Use the buttons to navigate between link jumps in the Manuals.

Assumed Knowledge

This documentation presumes that you have good knowledge about radio network planning principles and the radio technology to plan.

Document Conventions

Product history and versions

Up to and including version 9.1.x, this product was branded as a TEMS™ product, named TEMS CellPlanner. Since version 10.0 it belongs to Mentum and is branded as Mentum CellPlanner. In some text on version dependencies, the short name “CellPlanner” is used to not complicate the compatibility descriptions.

Abbreviated component names

The product consists of the following components: • Mentum CellPlanner Client, the planning application • Mentum CellPlanner Enterprise Server

• Mentum CellPlanner Zero Admin Server • Mentum CellPlanner User Administration • Mentum CellPlanner License Server

For increased readability, the manuals might abbreviate long names:

• Mentum CellPlanner without any component name refers to the Mentum CellPlanner Client only.

• Full names may be abbreviated, for example CellPlanner Enterprise Server, or Enterprise Server, abbreviates Mentum CellPlanner Enterprise Server.

• Mentum CellPlanner Server, or CellPlanner Server, stands for either Mentum CellPlanner Enterprise Server or Mentum CellPlanner Zero Admin Server. Window names, button names, and keyboard keys are displayed as bold text. Example: Click

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Common Features User’s Guide

Common Features Technical Reference Manual

Map Import Wizard User’s Guide

LTE User’s Guide

LTE Technical Reference Manual

GSM User’s Guide

GSM Technical Reference Manual

WiMAX User’s Guide

Describes the CellPlanner software components, system requirements, how to install components, how to obtain licenses, and how to check out licenses for off-line work. The procedures must be performed by a user with administrator privileges on the local computer. Some procedures require that you are an authorized Mentum CellPlanner administrator.

Includes work with projects, the explorer objects used for more than one radio technology, how to add sites and use site tools, filters, plots, neighbors, using survey data, AMI, tuning propagation models, ASMT, puncturing, export and import of common data, and how to administer and work with projects on server.

Describes radio technology independent algorithms, parameters and file formats.

GeoData User’s Guide

Describes geodata concepts, supported geodata formats, conversion between different map formats, how to use map data tools in Mentum CellPlanner. The chapters about providing and importing map data are intended for administrators of map data. Other chapters are intended for users of map data.

Describes how to import map data using a generic wizard similar to the one provided with Mentum LinkPlanner. The intended reader is administrator of map data.

Describes how to use LTE functions of Mentum CellPlanner, including analysis, and creation of plots and reports.

Describes LTE network planning principles, analysis details for advanced users, and physical cell ID (PCI) planning principles.

WCDMA User’s Guide

How to use WCDMA functions of Mentum CellPlanner, including analysis, and creation of plots and reports.

WCDMA Technical Reference Manual

Describes concepts and overviews of WCDMA algorithms, and how HSPA and MBMS are used in Mentum CellPlanner. Describes how to use the GSM functions of Mentum CellPlanner, including analysis, and creation of plots and reports. Describes overlaid/underlaid cell structures, reuse patterns, manual frequency planning, automatic frequency planning (AFP), automatic hopping frequency set (HFS) planning, optimization of BSIC, HSN and MAIO, fractional load planning, and effective subscriber modeling. Also describes the GSM algorithms and file formats used in Mentum CellPlanner.

Describes how to use the WiMAX functions of Mentum CellPlanner, including analysis, and creation of plots and reports. Glossary of terms, how

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This chapter provides an overview of the Mentum CellPlanner product.

Topics Page

About Mentum CellPlanner . . . 1-2 Installation . . . 1-2 Product Packaging. . . 1-2 Licenses. . . 1-3 Support and FAQ. . . 1-4 Send Us Your Comments. . . 1-6

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About Mentum CellPlanner

Mentum CellPlanner is a licensed graphical Windows based application for Mentum CellPlanner is a licensed graphical Windows based application for

designing, implementing, and optimizing mobile radio networks using geodata and designing, implementing, and optimizing mobile radio networks using geodata and optional drive test data. It assists you in performing complex tasks, including optional drive test data. It assists you in performing complex tasks, including network dimensioning, traffic planning, site configuration, frequency planning, and network dimensioning, traffic planning, site configuration, frequency planning, and network optimization. Mentum CellPlanner can be used stand-alone or in a client/ network optimization. Mentum CellPlanner can be used stand-alone or in a client/ server environment, and licenses may be in

server environment, and licenses may be installed locally or on a license serstalled locally or on a license serverver..

Installation

The

The Installation GuideInstallation Guide describes how to download and install software and how to describes how to download and install software and how to manage

manage LicensesLicenses..

Product Packaging

The product package includes the sof

The product package includes the software components listed below.tware components listed below.

What is actually installed depends on your selection in the installation wizard. What is actually installed depends on your selection in the installation wizard.

Some components require a license, see

Some components require a license, see Licensed ComponentsLicensed Components on page 1-3 on page 1-3.. The

The Installation GuideInstallation Guide provides an overview of each component and how the provides an overview of each component and how the components relate to

components relate to each other.each other. P

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• ManualsManuals

• Map tools, geodata conversion software, • Map tools, geodata conversion software,

demo maps, filters, scripts demo maps, filters, scripts •

• Citrix software - relevant only if you areCitrix software - relevant only if you are going to offer the Mentum CellPlanner going to offer the Mentum CellPlanner installation as a Citrix service

installation as a Citrix service

The main application, the most The main application, the most commonly used part of the suite of commonly used part of the suite of CellPlanner programs.

CellPlanner programs.

Named “CellPlanner Client” where Named “CellPlanner Client” where needed to distinguish from

needed to distinguish from CellPlanne

CellPlanner Server or r Server or otherother CellPlanne

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Care

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Licenses

The

The Installation GuideInstallation Guide describes concepts and use of Mentum CellPlanner licenses. describes concepts and use of Mentum CellPlanner licenses. •

• License installation License installation types - types - stand-alone and stand-alone and floatingfloating •

• License lock keys License lock keys for stand-alone licenses - for stand-alone licenses - USB dongle locked USB dongle locked and PC lockedand PC locked •

• How How to to install install licenseslicenses •

• How to How to activate activate licensed featurlicensed featureses •

• License commuting - License commuting - how to check how to check out floating licenses out floating licenses for off-line work for off-line work usingusing

Licensed Components

The following three

The following three Product ComponentsProduct Components are licensed: are licensed:

Radio Technology Features

Each of the radio technology software modules listed below require an installed and Each of the radio technology software modules listed below require an installed and activated license. How to use the radio technology software is described in adherent activated license. How to use the radio technology software is described in adherent user guides and technical reference manuals.

user guides and technical reference manuals. • GSM • GSM • WCDMA • WCDMA • WiMAX • WiMAX • LTE • LTE

Planning Features

Additional planning features can be used together with the radio technology Additional planning features can be used together with the radio technology software. These additional software modules require a license for the feature itself software. These additional software modules require a license for the feature itself and a license for the adherent radio technology:

and a license for the adherent radio technology: C

CeellllPPllaannnneerr TTo o ssttaarrt t CCeellllPPllaannnneer r yyoou u nneeeed d a a lliicceennsse e ffoor r aatt least one of the

least one of the Radio Technology FeaturesRadio Technology Features.. Additional licenses are required for each of the Additional licenses are required for each of the Radio

Radio TTechnology Featuresechnology Features and and PlanningPlanning

Features

Features to use. to use.

named “CellPlanner Client” in named “CellPlanner Client” in some contexts

some contexts

E

Enntteerrpprriisse e SSeerrvveerr LLiicceennsse e rreeqquuiirreed d tto o ssttaarrt t tthhe e sseerrvveerr Z

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• Automatic Frequencequency Plany Planningning RequirRequires GSM les GSM licensicense. This le. This license icense is reqis requireduired also for automatic HFS planning.

also for automatic HFS planning. • Automatic Measurement

• Automatic Measurement Integration and ASMT Integration and ASMT

Requires license for at least one of the

Requires license for at least one of the RadioRadio

Technology Features

ASMT = Automatic Sector Model Tuning ASMT = Automatic Sector Model Tuning ..

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Support and FAQ

Mentum Customer Care

Visit Customer

Visit Customer Care’Care’s website ats website at www.mentum.com/customer-carewww.mentum.com/customer-careto register,to register, enter the Self-Service Portal, or download software or documents.

enter the Self-Service Portal, or download software or documents.

Download

T

To download software o download software you need youryou need your

Manuals are included in the software package, but to download additional Manuals are included in the software package, but to download additional documents you need your

documents you need your

Self-Service

T

To enter the Self-Service portal to enter the Self-Service portal to read FAQ or submit or view cases, you need o read FAQ or submit or view cases, you need youryour customer

customer andand

Phone or E-mail

When you call or e-mail for technical support, ensure that you have your When you call or e-mail for technical support, ensure that you have your number and know which version

number and know which version of the software you are running. of the software you are running. YYou can obtainou can obtain this information using the About command from the Help menu.

this information using the About command from the Help menu. Phone: +1 866 921-9219 (toll free), +1 819 483-7094

Phone: +1 866 921-9219 (toll free), +1 819 483-7094 Fax: +1 819 483-7050

Fax: +1 819 483-7050 E-mail:

E-mail: [email protected]@mentum.com

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Hours: 9am – 7pm EST/EDT (Monday-Friday(Monday-Friday, excluding local holidays), excluding local holidays) Phone: +33 1 39264642

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Phone: +852 2593 1287 Fax: +852 2593 1234 Fax: +852 2593 1234 E-mail:

Hours: 9am – 6pm

Hours: 9am – 6pm HKT (Monday-FridayHKT (Monday-Friday, excluding local holidays), excluding local holidays)

When you request technical support outside of regular business hours, a Product When you request technical support outside of regular business hours, a Product Support Specialist will respond the next working day by telephone or e-mail, Support Specialist will respond the next working day by telephone or e-mail, depending upon the nature of the request.

depending upon the nature of the request. product ID

product ID andand passwordpassword.. product ID

product ID number. number.

product ID

product ID numbernumber user name user name password password..

product ID product ID

North America North America

Europe

Europe Middle Middle East East and and AfricaAfrica

Asia Pacific Asia Pacific

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Technical Information

When contacting Mentum Customer Care, you might be requested to provide technical information on your installation to facilitate troubleshooting. Do as follows to extract the technical information from your computer:

1. Select Help from the main window. The About

window appears as in the following example:

2. Click to open the window as in the example

below. Most information is automatically retrieved from your installation. About Mentum CellPlanner

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3. Enter the following information:

-- Your

- Problem description

4. To include the log file from the Logfile folder, select option

Select

5. To include the project file from the Project folder, select option

6. Enter the path of the

7. Click

troubleshooting Mentum CellPlanner are created in the specified folders.

8. Send the information in the

contact.

Send Us Your Comments

Feedback is important to us. Please take the time to send comments and

suggestions on the product you received and on the user documentation shipped with it. Send your comments to:

[email protected]

Product ID associated with your license

Contact person name or other contact information E-mail address

Include log file. Compress log to decrease the file size.

Include project file. Select Compress project to decrease the file size.

Output directory where the information will be stored. Collect information. A set of files with information relevant for

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2 LTE Network Planning Principles

This chapter provides an overview of LTE air interface properties and their influence on network planning principles applied in Mentum CellPlanner. In this document it is assumed that the reader has a general knowledge on the LTE air interface. Information on handling of fixed subscribers in the LTE Analysis is also described here. Current limitations in LTE network planning are summarized in the last section.

Topic Page

LTE Air interface Modeling in Mentum CellPlanner. . . 2-2 LTE Spectrum Flexibility . . . 2-2 LTE Multi-user Access and Channel Structure . . . 2-3 LTE Transmission Schemes . . . 2-4 Radio Channel Models for LTE . . . 2-5 Spectral Efficiency Techniques . . . 2-6 Data Rate Mappings . . . 2-7 LTE Frequency Band, Terminals, Bearers and Traffic Cases . . . 2-8 Planning of Fixed Subscribers in LTE. . . 2-10 Current Limitations in LTE System Modeling. . . 2-11

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2.1 LTE Air interface Modeling in Mentum CellPlanner

The LTE analysis functions in Mentum CellPlanner allow you planning of an LTE network based on geographical data, analyzing the network plan and presenting analysis results in plots and reports.

The air interface properties of LTE influence to a large extent the way an LTE network is simulated and analyzed in planning tools like Mentum CellPlanner.The following chapters provide an overview on these planning principles.

2.2 LTE Spectrum Flexibility

The LTE air interface is designed for high spectrum flexibility and capabilities of using a wide variety of different spectrum allocations. The LTE standard is based on a frequency allocation technique called Orthogonal Frequency Division Multiplexing -OFDM, which allows the use of a number of narrow-band channels for UL and DL transmissions. The frequency separation between these channels is chosen such that the different channels do not interfere with each other, even if used in adjacent order. Therefore, the channels are orthogonal to each other and there is no need for frequency planning in LTE as was done for e.g. GSM.

Unlike in WCDMA, where orthogonality between the different channels is achieved by orthogonal channelization codes, LTE provides orthogonality already in the radio frequency channel allocation. As a consequence, there is no code or power

planning required in the same manner as for e.g. in WCDMA.

Furthermore, the amount of sub-channels that can be allocated to UL and DL transmissions can be varied so that different spectrum bandwidths can be deployed, reaching from 1.4 MHz to 20 MHz.

In Mentum CellPlanner you can plan any LTE frequency band and spectrum

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2.3 LTE Multi-user Access and Channel Structure

The LTE air interface provides means for multiple users to access the system independently in UL and DL transmission. The corresponding access schemes are called Orthogonal Frequency Division Multiple Access (OFDMA) in DL and Single Carrier Frequency Division Multiple Access (SC-FDMA) in UL.

The main property of these access schemes is that multiple users can share parts of the assigned spectrum at the same time but on different sub-channels of the assigned LTE frequency band.

The channel structure of LTE is designed in such a way that the channels are

provided in the time domain as time slots, and in the frequency domain as a number of sub-channels (time/frequency matrix) over which the information is sent. The basic air interface resource in LTE is called a Resource Block (RB). It consists of 12 sub-carriers of 15 kHz bandwidth each (sums up to 180 kHz) in a time slot of 0.5 ms. As the scheduler allocates radio resources on a 1 ms sub frame basis (2 time slots) the TTI of the LTE air interface is 1 ms.

Based on the radio conditions in terms of signal quality, on the transmission schemes supported by the LTE network equipment (eNodeB) and on the terminal capabilities the scheduler will assign a certain number of RBs to each of the terminals connected to a cell. The resource allocation is in that way mainly

controlled by the scheduling function in the eNodeB. There is no channel switching in LTE as was the case for e.g. WCDMA.

For capacity planning this is an important advantage as th e available cell capacity in UL and DL is provided in number of RBs. Each RB is able to carry a certain amount of data on the physical layer, Layer 1. The actual amount of data carried is

depending on the signal quality of the UL and DL and on the Modulation and Coding Scheme (MCS) supported by the cells and by the terminals.

For network planning the achievable data rates are calculated for Layer 1 only. They are retrieved from so-called data rate mapping tables , which provide measured data rates per RB for different transmission schemes, multiplexing and coding schemes, terminal types and signal quality parameters (Signal to interference plus noise ratio C/(I+N)) as well as for different radio channel models.

In the current implementation of Mentum CellPlanner these data rate mapping tables are hard-coded and cannot be edited by the user. The main reason is the complexity of these tables and the fact that there are no large-scale deployments and measurements of real LTE performance available yet. As more vendor

independent measured data rates become available these tables will be updated and will also be available for user-defined parameter settings.

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2.4 LTE Transmission Schemes

Already in WCDMA/HSPA higher order modulation schemes were applied to increase the spectrum efficiency of the air interface. The more modulation and coding schemes that are available for the link adaptation algorithms, the more flexible the radio interface can be controlled in terms of achievable bit rate under varying radio conditions. Especially for users in good radio conditions the use of higher order modulation and less complex coding schemes leads to a higher data rate and higher spectrum efficiency of the transmission.

In addition to the modulation and coding schemes, several transmit and/or receive paths can be used in the air interface to increase the amount of information that can be transported over a physical radio channel. Depending on the antenna configuration and on the capabilities of terminals and eNodeB cells, advanced transmission schemes can be applied.

For LTE the use of multiple antennas at both the base station and the terminal side has been standardized. Such configuration allows the application of diversity transmission, diversity reception and spatial multiplexing using MIMO.

Using spatial multiplexing and advanced signal processing in both the transmitters and receivers, the data stream can be split into several layers, with each layer transporting the same amount of physical data. This way, the data rate for the user can be increased up to four times for 4 Tx and 4 Rx antennas and the spectrum efficiency increases up to four times as well.

Currently the LTE Analysis supports the following transmission schemes:

The choice of transmission scheme during network planning of an LTE system depends on the achieved signal quality of the best serving cell for each position covered by the network. The LTE Analysis algorithm calculates the achieved C/(I+N) for the best server coverage area of all cells and evaluates the best possible

transmission scheme to be applied for data rate calculations. The corresponding data rate tables are then selected from th e terminal capabilities. The DL transmission scheme and rank are provided in the DL Transmission Scheme Plot (as described in the Mentum CellPlanner LTE User’s Guide ) after the LTE Analysis has been done successfully.

Transmission scheme Used in Description

1x2 MRC, also called SIMO

DL and UL Single transmit antenna at the eNodeB

and receiver diversity at the terminal

2x2 Tx diversity DL Two transmit antennas with transmit

diversity at the eNodeB and receiver diversity at the terminal

2x2 Tx diversity combined with 2x2 MIMO

DL Two transmit antennas at the eNodeB

with transmission of separate data streams on each antenna and

corresponding spatial multiplexing at the terminal side

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2.5 Radio Channel Models for LTE

One important parameter for simulation of the radio interface in LTE is the actual radio channel bandwidth that is used for LTE data transmissions. The radio channel of LTE can cover up to 20 MHz of radio signal bandwidth, which is four times as much as WCDMA uses. Consequently, it can be expected, that the radio channel frequency response is different from the one modeled in the ITU channel models for WCDMA. 3GPP has, therefore, decided to extend the existing ITU channel models to cater for the larger delay spread of the wider band radio channels in LTE.

The channel models are called Extended ITU Models and cover the following types: • Extended Pedestrian A - EPA

• Extended Typical Urban - ETU • Extended Vehicular A - EVA

In CellPlanner the channel models are selected in connection with the data rate mapping tables in the terminal editor, see figure below. For details refer to options for UL and DL data rate mappings in the Mentum CellPlanner LTE User’s Guide . The choice of channel model defines the set of data rate mapping tables that are applied for calculation of the achieved UL and DL data rates in Mentum CellPlanner.

Depending on the speed of the terminal a certain doppler shift applies to the carrier frequency. The Extended ITU Channel Models reflect the different doppler shifts of 5 Hz (low shift), 70 Hz (medium shift) and 300 Hz (high shift), which correspond to terminal velocities of approximately 2, 30 and 130 km/h respectively.

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2.6 Spectral Efficiency Techniques

eNodeB transmitters send reference signals to UEs, which measure the radio conditions and report back the highest pos sible modulation and coding scheme for the moment. The spectral efficiency technique applied in the eNodeB decides how to use the UE feedback, which affects the data rate and potentially the capacity. The spectral efficiency techniques supported in Mentum CellPlanner are as follows:

• Closed-loop MIMO requires frequent feedback from the UEs to select an optimal coding in every moment, quickly adapting the transmitter’s pre-coding to the channel conditions. This technique yields high performance in low-speed environments, but is not suitable for connections with fast moving UEs as the heavy signaling makes it sensitive to channel variations.

• Open-loop MIMO uses a fixed pre-coding and does not require any fast feedback from the UEs, hence this technique is suitable in high-speed environments.

In real networks this technique is configured as a system parameter, but in Mentum CellPlanner it is modeled as a terminal parameter together with the channel model. Irrespective of spectral efficiency technique, a MIMO capable eNodeB dynamically applies the most efficient transmission scheme according to the channel conditions. Spatial multiplexing with different data streams on each antenna can be applied under good conditions, while antennas switch over to transmit diversity with the same data stream on both antennas when the channel quality is lower.

The selection of spectral efficiency technique is relevant only when calculating DL data rate for 2x2 MIMO connections.

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2.7 Data Rate Mappings

Each supported combination of UE speed (corresponding to doppler shift), channel model, and spectral efficiency technique has its own data rate mapping table in UL and DL respectively, with values from a link curve . Link curves map the data rate per RB as a function of SINR.

The LTE Analysis retrieves the highest possible bit rate per cell from the link curve corresponding to the selected data rate mapping of the terminal, considering the configured cell capabilities in terms of number of tx antennas and MIMO support. Each downlink data rate mapping table contains mappings for 2x2 MIMO (one for closed-loop MIMO, one for open-loop MIMO), 2x2 Tx diversity and SIMO. Which mapping that will be used depends on the capability of the cell. If the cell is capable of using both 2x2 Tx diversity and 2x2 MIMO, the best of those schemes will automatically be selected dependant on the SINR. At high SINR, the data rate mapping corresponding to the selected spectral efficiency technique of 2x2 MIMO is applied. At low SIR, Mentum CellPlanner selects 2x2 Tx diversity automatically when this gives higher data rate.

Each uplink data rate mapping table contains a mapping only for SIMO (also called 1x2 MRC), hence there is no 2x2 MIMO or Tx diversity in the uplink. The algorithms and link curves assume that cells use 2 Rx antennas. In case you have configured a cell to use 1 Rx antenna, the calculated SINR is decreased by 3 dB to find the corresponding UL data rate. Also, if you have configured use of 4 Rx antennas, the same mapping as for 2 Rx antennas will be used (limitation in current version).

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2.8 LTE Frequency Band, Terminals, Bearers and Traffic

Cases

For the LTE Analysis as well as for Plot and Report Generation different properties of the LTE system, of base stations and of terminals need to be combined. This chapter provides background information on how these properties relate to each other and in which context they are used in Mentum CellPlanner.

A general overview on how system and equipment properties are mapped to each other is provided in the following figure:

The LTE Analysis takes terminal, base station and system parameters into account and generates plots and reports for -so called- Traffic Cases. A Traffic Case is a combination of an LTE bearer and a terminal. This way, the network planner can evaluate the expected performance of the network for different terminals using LTE bearers with different QoS and priority settings. A Traffic Case is -in other words- a representation of a subscriber class that is using a certain terminal type and a certain LTE bearer.

The Monte Carlo Simulator in the LTE Analysis generates mobile terminals based upon a traffic demand mix. In a traffic demand mix one or several traffic cases are combined with their respective traffic demand (either with uniform or with a map-based or area-map-based distribution).

An LTE bearer comprises of an LTE frequency band. Some of the properties of the LTE Frequency Band are defined by the LTE Carrier Mapping.

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The terminal comprises of a terminal category and LTE specific parameters. Such parameters are data rate mapping tables and radio related parameters, some of which can be edited by the user.

During the LTE analysis all above parameters are applied in an appropriate manner. For details on how the different parameters influence the results of the LTE Analysis refer to chapter Influence of Parameter Settings on Analysis Results on page 3-15.

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2.9 Planning of Fixed Subscribers in LTE

Mentum CellPlanner allows advanced analysis of fixed subscribers in an LTE

network. The properties of fixed subscribers differ from those of mobile terminals. The following attributes are considered in the LTE Analysis for fixed subscribers:

• Fixed subscriber positions are edited manually or imported using a Mentum CellPlanner import function.

• Fixed subscribers may use a directional antenna, which provides a certain side-lobe attenuation for interfering cells that are not co-located with the best serving cell. The side lobe attenuation of the terminal antenna is set in the terminal editor. For the serving cell of a fixed subscriber the full antenna gain without side lobe attenuation is applied in the algorithms.

• Fixed subscribers may use the same LTE band, LTE terminal types and LTE bearers as the mobile terminals. There is no need to assign separate bands or bearers to fixed terminals. The traffic cases us ed for mobile terminals may also be applied to fixed subscribers.

• The pathloss and best server calculations for fixed subscribers are part of the LTE Analysis algorithm, including plot and report generation. For details see chapter Simulator Structure for LTE Analysis on page 3-5.

• Simulation of random fading is not applied for fixed terminals as they do not move in the network.

• Slow fade margins (log-normal fading) are applied to fixed subscribers in the same manner as for mobile terminals. The fade margin is position (bin) dependent.

• User scheduling and resource allocation is during the LTE Analysis combined with the resource allocation of mobile terminals depending on the traffic cases selected. Only fixed subscriber positions that allow simultaneous UL and DL connection to the serving cell are allowed to compete with mobile terminals for resources in accordance with their QoS and priority setting s.

• The position of fixed subscribers is unchanged during the entire simulation of the LTE network, unlike mobile terminals, the position of which may be

generated for each trial in a random fashion.

• The traffic demand for fixed subscribers is derived from the density of subscribers as defined by their location in the LTE network coverage area. • Fixed subscribers are during the LTE Analysis not part of the traffic demand mix

(as defined for mobile terminals) since their traffic demand is handled

separately. This is connected to the requirement of fixed positions, which has an influence on how the random user generation algorithm of the Monte Carlo Simulator generates and distributes mobile terminals.

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2.10 Current Limitations in LTE System Modeling

LTE Systems are currently being deployed in large network roll-outs. The LTE system performance parameters that are available today for netw ork planning are derived mainly from link and system simulations. Adjustments of these parameters are required as soon as more real network performance data becomes available. Furthermore, the 3GPP Standards for LTE support a wide range of different functions and features for LTE eNodeB and terminal equipment. Not all of these functions are implemented in currently available equipment.

For these reasons Mentum CellPlanner has the following limitations: • Multi-user MIMO not supported

The current implementation of MIMO modeling does not cater for multi-user detection functions.

• Interference Rejection Combining not supported

This function is currently not modeled in Mentum CellPlanner. • Inter-cell Interference Coordination not supported

This function is currently not modeled in Mentum CellPlanner. • Maximum 2 Rx antennas in cells

4 Rx antennas may be configured, but this setting will be ignored and calculations will use 2 Rx antennas.

The planning algorithms and capabilities of Mentum CellPlanner will be updated as soon as there is simulated or measured performance data for these functions available.

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3 LTE Analysis - Details for Advanced Users

This chapter provides a detailed overview of the LTE Analysis Module in Mentum CellPlanner. In this document it is assumed that the reader has already general knowledge on setting basic analysis parameters and on running the LTE Analysis.

Topic Page

On Simulators for LTE Network Planning . . . 3-2 Best Server Analysis for LTE . . . 3-3 Simulator Structure for LTE Analysis . . . 3-5 Scheduler Options . . . 3-9 Round Robin Scheduler . . . 3-9 Channel Dependent Scheduler . . . 3-10 QoS Aware Scheduler. . . 3-11 Reasons for Blocking of Users during Simulation . . . 3-12 Connected . . . 3-12 Too Many Users . . . 3-12 Insufficient DL . . . 3-12 Insufficient UL . . . 3-13 Rejected in DL . . . 3-13 Rejected in UL . . . 3-13 DL GBR Not Reached . . . 3-13 UL GBR Not Reached . . . 3-13 DL Overloaded . . . 3-13 UL Overloaded . . . 3-14 Influence of Parameter Settings on Analysis Results . . . 3-15 UL Power Backoff . . . 3-15 UL Frequency Compensation . . . 3-16 Admission Control Parameters . . . 3-17 Fade Margins and Random Fading . . . 3-20 Rejecting Users on Resource Shortage . . . 3-21 Number of Transmit Antennas in a Cell . . . 3-23 Activity, Load and Utilization . . . 3-25 Bin Probing in Plot Generation . . . 3-28

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3.1 On Simulators for LTE Network Planning

The LTE System applies sophisticated algorithms of Radio Resource Management for connecting users and terminals to the network. Besides sharing the same radio resources the traffic management algorithms are designed to provide maximum spectrum efficiency, i.e. the maximum data throughput for a given radio spectrum. This involves intelligent scheduling of users in good radio conditions for high data rates while providing users in worse radio conditions with a minimum average data rate for the requested services to run properly. Some users in the network require a high Quality of Service with guaranteed bit rates for their connection while other users are satisfied with a good average bit rate, independent of th eir position in the network.

In a mobile network, users move with varying speed between the cells, which leads to an always fluctuating traffic load in the cells.

Furthermore, LTE is a packet switched data system for mobile and fixed applications. The nature of packet data traffic is bursty, with users being active or inactive at different points in time. The user activity/inactivity is hard to predict in a planning tool.

All these conditions call for a radio resource management, which takes a multitude of radio, network and user dependent parameters into account. Such user traffic handling cannot be modeled in a planning tool straight fo rward. Instead, advanced simulation algorithms are used to model the expected user and network behavior under varying traffic load and radio conditions.

The LTE Analysis algorithm in Mentum CellPlanner is based on a sophisticated Monte Carlo Simulation Engine. A large amount of random number generators models the input conditions of the simulator. The simulator engine aims at maximum spectrum efficiency of the radio network. Based on a user defined number of trials, the simulation algorithms model the mobility and activity behavior of mobile users. Once a trial has converged to a stable state, intermediate data on user connections and on achieved data rates in UL and DL are collected and a new trial with the same or a different user distribution in the network is started. After running a number of trials the calculation results are evaluated in a statistical manner, to assess the performance of the network and to optimize the network plan.

The results of the LTE Analysis are input to other planning functions in Mentum CellPlanner such as the Cell ID planning and optimization. This algorithm is described in chapter LTE Cell ID Planning in this Technical Reference Guide.

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3.2 Best Server Analysis for LTE

In a multi-cell radio network such as LTE most of the expected user positions are covered by several cells of LTE base stations. It is, therefore, important to find for every position in the network (in Mentum CellPlanner called a bin ) the best serving cell and cells that might act as second or third best server or as potential interferer. Mentum CellPlanner uses the Best Server Analysis algorithm to find such list of best servers for all bins in the network. The following figure shows an overview on the input and output functions of this algorithm.

Before the Best Server Algorithm can be run, the network and map data needs to be provided by the planner and the pathloss prediction results must be available. Based on the pathloss predictions from all cells to all bins in the network a

composite pathloss matrix (CPLM) is generated, which contains for every bin only those cells that fulfill the input requirements set by the planner.

For every traffic case, as defined in the traffic demand mix, the best server algorithm finds those cells that cover a bin for the respective traffic case(-s) with a minimum

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If the distance between a bin and a cell’s antenna (the closest antenna if there are more than one) is higher than the cell-specific cell range limit (normal or extended), the cell is removed from the Best server list of that bin. If a cell in the Best server list is a donor cell of a radio repeater, the distance between the donor cell and the radio repeater is added to the distance between the radio repeater and the bin.

As the LTE network applies a frequency re-use of 1 and there are more than one cell covering most of the bins in the network there is a risk for mutual interference between the cells. Taking the amount of cells and their corresponding signal strength into account, the best server algorithm calculates the signal quality of the best serving cell as C/(I+N) and C/N for every bin.

Cell selection and reselection as well as handover requires UEs to measure on neighboring cells. The best server algorithm calculates one of those measured qualities, the received power of the reference signal abbreviated as RSRP.

In order to serve a bin with a minimum data rate a certain signal quality from the best serving cell is required. The data rate is retrieved from the data rate mapping tables as well as from the network properties in terms of DL Transmission Scheme and taking the achieved signal quality into account.

The output of the Best Server Analysis is a list of Best and n-best servers and with the achieved C/(I+N) for every bin in the unloaded network. This information is fed into the LTE Analysis module for simulation of subscribers and traffic.

Observe that the Best Server Algorithm as described above only operates on mobile subscribers. The Best Server Analysis for fixed subscribers is part of the LTE Analysis Algorithm and is described in chapter Simulator Structure for LTE Analysis on page 3-5 .

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3.3 Simulator Structure for LTE Analysis

This chapter provides an overview on the main simulator principles implemented in the LTE Analysis of Mentum CellPlanner.

The following figure shows how the most important functions o f the simulator are designed, a simplified description of which is provided in the paragraphs below.

Based on the input data from the Best Server Analysis for LTE and on the traffic demand as specified for each traffic case in the traffic demand mix mobile terminals are generated in the best server coverage areas of the cells. The bin position of these terminals is now locked for the duration of the current simulator trial.

If the option “Use Random Fading” is selected for the LTE Analysis, the calculated signal strength values for UL and DL for th e best serving cell and all interfering cells

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mobile UE may become its best server. For fixed subscribers random fading simulation is not applied.

In case the network plan shall also cater for fixed subscribers, the planner can select fixed subscriber positions based on an imported subscriber list or manually

generated fixed subscriber positions. The LTE Analysis module runs a pathloss prediction for all fixed subscriber positions to all cells in the network and performs a best server analysis similar to the algorithm for mobile terminals. For calculation of the signal quality from the best serving cell, the possible use of directional antennas at the fixed subscriber position is considered by taking the antenna side lobe attenuation (terminal parameter) of the fixed subscriber antenna into account. In the sub-sequent algorithms the fixed and mobile subscribers are treated in a similar manner by the LTE Analysis, i.e. they have to compete on equal basis for the cell capacity resources.

If for an LTE radio bearer a non-zero value was set for the Guaranteed Bit Rate in UL and/or DL, this bearer will be treated as a QoS bearer. All fixed and mobile

subscribers using this bearer in the current trial of the simulation are now sorted in accordance with their QoS class (GBR or non-GBR). Within their QoS class the subscribers are sorted in accordance with their LTE bearer priority. The output of this function is a sorted list of subscribers with their respective traffic case, which shall now be scheduled for a connection to the network.

The scheduling starts with an UL/DL connection check for the scheduled users. If the minimum data rate for a scheduled subscriber can be achieved, the algorithm calculates an activity factor for UL and DL for this us er. If the user connection check fails, the subscriber is marked disconnected and the corresponding status flag is s et. The reasons for blocking subscribers in the LTE Analysis are described in chapter Reasons for Blocking of Users during Simulation on page 3-12.

Users are first ensured to be connected in UL. The main reason for this limitation is that DL Power Control and Link Adaptation rely on CQI measurements and

reporting of the terminals in the UL. Users that are connected and active on UL can now be scheduled also for DL connections.

If a Guaranteed Bit Rate (GBR) has been set for the Radio Bearer of the scheduled subscriber, the algorithms check whether or not this GBR can be achieved.

Depending on the capacity resources of the serving cell, the subscriber might be connected with the requested GBR or with a higher average bit rate. All cell capacity that is not used by subscribers in a cell is calculated and reported as “Not served data rate”.

A GBR-subscriber that cannot be connected on GBR is blocked and the subscriber status is recorded. The algorithm continues with the next subs criber in priority order. Subscribers with a bearer setting “Reject on resource shortage” set to true are blocked in case the cell capacity is not sufficient to connect this subscriber with the requested bit rate. The subscriber status is recorded and summarized after the simulation in the statistics report.

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For all connected users the required UL and DL received power is calculated and UL and DL transmit power is assigned. Based on the known transmit power values the UL and DL interference can be calculated for every bin.

Depending on the calculated interference, which is generated by all active

subscribers, the power assigned for cells and terminals may be adjusted within the capabilities of the terminals and cells. As long as there is an adjustment of assigned power values required, the received interference will change and a new interference calculation needs to be performed.

The convergence check evaluates changes in UL interference in the cell and in the DL transmit activity status between two consecutive iterations. If the UL interference does not change by more than the convergence limit (LTE Analysis parameter) defined in dB by the planner, the UL is considered stable and convergence is reached. For the DL convergence is reached if the DL activity status (“transmitting in DL” or “DL switched off”) did not change, i.e. the DL status is stable.

As long as there are cells that did not reach convergence a new iteration will be started, beginning with UL and DL connection checks for the subscribers. A new iteration can be initiated as long as the maximum number of iterations for each trial as defined by the planner is not reached. If the maximum number of iterations has been reached and the network has not converged to a stable state yet, the trial is set to status “unsuccessful” and a new trial is generated, starting with a new random selection of subscribers and of their position in the network.

If convergence has been reached for the network, the final power settings fo r cells and terminals are used to calculate the UL and DL interference and the received signal quality as C/(I+N). Applying the data rate mapping tables in accordance with the terminal capabilities, the achieved UL and DL data rates are calculated. For this calculation the log-normal fade margins are not considered, since it cannot be assumed that all active and connected subscribers are subject to down-fading at the same time.

If there is still one trial to be done by the simulator (maximum number of trials not reached), the next trial starts with a random generation of subscribers (UEs) in the network.

If the last trial has been performed, final calculations are done and the plots and reports are generated and stored on the hard-disk.

The final calculations include the following parameters:

• total UL and DL utilization and update of link utilization in the cell editor • number of served and blocked subscribers

• achieved data rates of served users and data rates not served or blocked. The data rate plots are generated from these values.

• cell activity parameters depending on the link utilization. The cell activity is controlled by a random algorithm and simulates changes in cell activity/ inactivity for UL and DL. This feature reflects the bursty nature of packet data

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• calculation of statistical values from all trials (minimum, maximum, average parameter values and their standard deviation). The average value of the calculated parameters is used for plot generation.

• inclusion of fade margins in plot values of signal strength and UL power margin A description of plots and reports generated by the LTE Analysis is provided in the Mentum CellPlanner LTE User’s Guide .

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3.4 Scheduler Options

The scheduler in the LTE eNodeB is an advanced algorithm for radio resource management, which assigns radio resources to subscribers while taking the following main conditions into account:

• UL and DL cell activity

• UL interference and noise rise

• achieved signal quality of individual subscriber connections (reported by terminal through CQI-messages)

• QoS requirements and priority of radio bearers

• data rate requirements in UL and DL for individual subscriber connections • number of available Resource Blocks

• number of available LTE carriers

• maximum number of allowed UL and DL users (admission control) • maximum number of simultaneous UL users (scheduling)

• options for bit rate shaping for active subscribers, i.e. the scheduler sets an upper limit on the bit rate that can be allocated to a subscriber

• resource blocks are randomly allocated per carrier according to the principle of so called random frequency allocation

The Monte Carlo Simulator in Mentum CellPlanner is designed to model these functions in order to provide a realistic evaluation of the expected LTE network performance.

This chapter describes the different scheduler options that are integrated into the simulation engine for the LTE Analysis for both UL and D L modeling.

3.4.1 Round Robin Scheduler

The Round Robin scheduling algorithm assumes that the active subscribers have equal weight and priority and assigns the UL and D L resources in such a way that as many users as possible are connected with nearly equal data rates. In this concept the subscribers are connected in random order with their average bit rate. There is no sorting of subscribers and consequently, any settings for QoS or priority

requirements are ignored by the scheduler.

The scheduler assigns capacity resources until the maximum DL load is reached. Another limiting parameter is the maximum number of subscribers per cell.

Once the capacity resource limit is reached, admission control algorithms will block new connection attempts of subscribers. Those subscribers that use LTE radio bearers with checked option “Reject on resource shortage” are blocked first. All

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In case there is a high number of connection attempts to the cells, the scheduler will divide the available capacity into approximately equal shares.

In cases of only few connection attempts and when there is unused capacity available in the cell, the scheduler randomly assigns a higher share of capacity resources to some users. One of the reasons for certain “remaining” capacity is the fact that subscribers in favorable radio conditions might not require a full (equal) share of the assigned capacity resources to achieve the requested average data rate. In such a case the “spare capacity” is distributed to users in less favorable conditions to increase their share of the resources and thereby also their achieved data rates. The Round Robin scheduler has the main focus on fairness in dis tribution of capacity resources to as many subscribers as possible.

3.4.2 Channel Dependent Scheduler

The channel dependent scheduler optimizes the capacity assignments in such a way that subscribers in favorable radio conditions get a larger share of the available capacity resources. Subscribers in less favorable radio conditions are served on a much lower data rate with the aim to satisfy their minimum data rate requirements. The main mechanism in the channel dependent scheduler is an evaluation of the achieved signal quality and an assignment of weighting coefficients for active users. Subscribers with a high achieved C/(I+N) are assigned a higher weight than

subscribers in less favorable conditions. As a result, the scheduler assigns a larger amount of capacity shares to subscribers in good radio conditions. Once these users are served on their maximum achievable data rate, the remaining capacity is shared between subscribers with lower weighting coefficients. The scheduler also

simulates sharing of the UL channel resources including bit rate shaping.

The channel dependent scheduler prioritizes maximum spectrum efficiency (highest cell throughput for a given capacity pool) at the expense of fairness in resource sharing.

The remaining functions of the scheduler are similar to the Round Robin scheduler. There is no sorting of subscribers based on QoS or priority requirements in the LTE radio bearers. Subscribers on radio bearers with the option “Reject on resource shortage” set to true are blocked first in a random fashion in case the cell load limits are reached.

The channel dependent scheduler can achieve a higher data rate for some of the users and can increase the total cell throughput as compared to the Round Robin scheduler. This results in a certain scheduling gain, which can be entered by the network planner as a parameter for the scheduler options in the LTE Analysis window.

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3.4.3 QoS Aware Scheduler

This scheduler takes QoS settings and priority for radio bearers into account. If the planner has set a non-zero value for the Guaranteed Bit Rate on UL and/or DL for a radio bearer, this bearer is considered a QoS bearer granted a certain bit rate. This has a strong influence on the sorting of subscribers in the scheduler for connection attempts. Also, the priority of the bearers is considered when sorting subscribers within the same QoS class (GBR or non-GBR).

The first operation of the scheduler is the sorting of sub scribers in accordance with their QoS and priority settings. In case the maximum number of users is exceeded, the simulator’s signaling resources are not sufficient. Those at th e end of the sorted list will be blocked first with blocking reason “Too many users” in order to allow higher priority subscribers to get connected.

The next operation of the scheduler involves evaluating if the requested bit rate can be satisfied for the scheduled subscribers. This algorithm takes the user-defined scheduling gain into account. If the requested bit rate is higher than the available one, these subscribers are blocked with the reason “UL (or DL) overloaded”. In case the load limits are still exceeded at subscriber connection attempts, non- GBR subscribers are blocked starting from the end of the sorted priority list. Those subscribers on radio bearers with the option “Reject on resource shortage” set to true are blocked first.

If these measures did not resolve the overload situation the scheduler identifies GBR-subscribers and blocks them one by one, starting with the subscribers with lowest priority, until the overload is resolved. The blocking reason is set to “DL (or UL) GBR not reached”.

In the case that all subscribers on GBR radio bearers have been served by the network in accordance with their requested bit rates, t he remaining cell capacity is shared by active subscribers on equal priority in accordance with the Round Robin scheduling principles until the maximum assigned UL and DL load is achieved. The QoS aware scheduler favors high priority subscribers with a guaranteed bit rat e assignment to the largest possible extent. Lower priority subscribers without bit rate guaranteed share the remaining resources in a fair manner (Round Robin).