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Training Programme

1. LTE Planning Overview

2. Modelling a LTE Network

3. LTE Predictions

4. Frequency and PCI Plan Analysis

5. Monte-Carlo Based Simulations

(3)

1. LTE Planning Overview

LTE Features Supported in Atoll

LTE Workflow in Atoll

(4)

LTE Features supported in Atoll

Supports Evolved UTRA (3GPP Release 8 LTE) Networks

Various Frequency Bands

Scalable Channel Bandwidths

Resource Blocks per Channel and Sampling Frequencies

Support of TDD and FDD Frame Structures

Half-frame/Full-frame Switching Point Periodicities for TDD

Normal and Extended Cyclic Prefixes

Downlink and Uplink Control Channels and Overheads

• Downlink and uplink reference signals, PSS, SSS, PBCH, PDCCH, PUCCH, etc.

RSRP, RSSI and RSRQ Support in predictions and Simulations

(5)

LTE Features supported in Atoll

Supports Evolved UTRA (3GPP Release 8 LTE) Networks

Physical Cell IDs Implementation

Inter-Cell Interference Coordination Support

• Fractional Frequency Reuse Modelling

Support of Fractional Power Control (UL)

Support of Directional CPE Antennas

Signal Level Based Coverage Planning

CINR Based Coverage Planning

Possibility of Fixed Subscriber Database for Fixed Applications

(6)

Specific Module

LTE Features supported in Atoll

Supports Evolved UTRA (3GPP Release 8 LTE) Networks

Network Capacity Analysis using Monte Carlo Simulations

Scheduling and Resource Allocation in Two-dimensional Frames

Multiple Input Multiple Output (MIMO) Systems

• Transmit and Receive Diversity

• Single-User MIMO or spatial multiplexing • Adaptive MIMO Switch (AMS)

• Modelling of Multi-User MIMO (collaborative MIMO – UL only)

Tools for Resource Allocation

• Automatic Allocation of Neighbours • Automatic Allocation of Physical Cell IDs • Automatic Allocation of Frequencies (AFP)

Network Verification Possible using Drive Test Data

(7)

Slide 7 of 82

LTE Workflow in Atoll

© Forsk 2011 Confidential – Do not share without prior permission

Open an existing project or create a new one

Prediction Study Reports Traffic Maps

Network Configuration - Add network elements

- Change parameters

User-defined Values Automatic or Manual Neighbour Allocation

Basic Predictions (Best Server, Signal Level)

Monte-Carlo Simulations

Signal Quality and Throughput Predictions Cell Load Conditions Subscriber Lists And/or Frequency Plan Analysis

Automatic or Manual Frequency Planning Automatic or Manual Physical Cell ID Planning

(8)

Training Programme

1. LTE Planning Overview

2. Modelling a LTE Network

3. LTE Predictions

4. Frequency and PCI Plan Analysis

5. Monte-Carlo Based Simulations

(9)

2. Modelling a LTE Network

Global Settings

Frequency Band definition

Frame Structure Settings

Radio Parameters

Site

Transmitters

Cells

Equipment Parameters

User-definable reception characteristics

(10)

Global Settings (1/2)

Frequency Bands

Atoll can model multi-band networks within the same document

TDD (Time Division Duplexing) or FDD (Frequency Division Duplexing)

One frequency band assigned to each cell

(11)

LTE Frame Structure definition

System-level constants (Hard-coded)

• Width of a resource block (180 kHz) • Frame duration (10 ms)

Other control channel overheads defined by 3GPP (calculated based on 3GPP specs)

• Reference signals, PSS, SSS, PBCH, etc.

Global Settings (2/2)

© Forsk 2011 Confidential – Do not share without prior permission Slide 11 of 82

TDD option only : Switch from DL to UL

every half frame (default) or every frame Number of SD for PDCCH (0,1,2 or 3) carrying DL and UL Resource allocation information Normal (default) or extended

cyclic prefix (No. of SD per slot)  e.g.: at 15 kHz, 7 SD/slot (normal) or 6 SD/slot (extended)

Average number of resource blocks for

(12)

Radio Parameters Overview

Site

X (longitude) and Y (latitude)

Transmitters

Activity

Antenna configuration (model, height, azimuth, mechanical & electrical tilts...)

UL & DL Losses / UL Noise Figure

Propagation (Model, Radius and resolution)

Cells

Frequency Band & Channel

PCI

Power definition

Min RSRP

UL & DL Load

Diversity Support

Neighbours

© Forsk 2011 Confidential – Do not share without prior permission Slide 12 of 82 Presented in General Features

(13)

Transmitter Parameters

© Forsk 2011 Confidential – Do not share without prior permission Slide 13 of 82

Propagation settings Antenna Configuration and Losses

parameters

Cells parameters (see next slide)

Antenna Configuration DL and UL total losses, UL noise figure

(14)

Cell Parameters

Inputs of the neighbour allocation algorithm

Neighbour list

Cell activity

Power and energy offsets from computed

reference signal Cell’s frequency band

Channel number in the frequency band (and

allocation status)

DL traffic load Physical Cell ID + resulting PSS/SSS (and allocation status)

MIMO Configuration Min RSRP used as cell

coverage limit

UL noise rise due to surrounding mobiles

© Forsk 2011 Confidential – Do not share without prior permission Slide 14 of 82

ICIC and Fractional Power Control Parameters

(Advanced)

Load Conditions

(15)

Equipment Parameters (1/2)

Bearers (Modulation and Coding Schemes) definition

User-definable bearer efficiencies

(useful bits per resource element)

Bearer selection thresholds for link adaptation

Quality indicator graphs

BLER used to model the effect of errors in data reception

(16)

Equipment Parameters (2/2)

Multiple Input Multiple Output Systems

Diversity and SU-MIMO gains

• Definable per bearer and antenna configuration • Depend on the clutter class where users are located

MU-MIMO gain

• Definable per cell or

• Calculated during Monte Carlo simulations using intelligent multi-user scheduling on two antenna ports (Layered Space-time Scheduling)

(17)

Training Programme

1. LTE Planning Overview

2. Modelling a LTE Network

3. LTE Predictions

4. Frequency and PCI Plan Analysis

5. Monte-Carlo Based Simulations

(18)

3. LTE Predictions

Introduction

Parameters used in Predictions

Prediction Settings

Fast Link Adaptation Modelling

Coverage Prediction Examples

Point Analysis Studies

(19)

Introduction

Coverage Predictions

General Studies based on Downlink Reference Signal Levels

• Best server plot based on downlink reference signal levels

• Multiple server coverage based on downlink reference signal levels • Reference signal level plots

• Reference signal CNR plots

• RSRP (Average Reference Signal Level Received Power per Subcarrier) plots

LTE UL and DL Specific Studies

• SS, PDSCH, PBCH, PDCCH and PUSCH/PUCCH Signal Level Plots • SS, PDSCH, PBCH, PDCCH and PUSCH/PUCCH CNR Plots

• Quality Studies (RSSI – Received Signal Strength Indicator, RSRQ – Reference Signal Received Quality, Reference Signal, SS, PDSCH, PBCH, PDCCH and PUSCH/PUCCH CINR and interference plots, UL Allocated Bandwidth, UL Transmission Power)

• Best Bearer and Modulation Plots based on PDSCH and PUSCH CINR Levels

• Throughput and Cell Capacity per pixel plots based on PDSCH and PUSCH CINR levels • Peak RLC, Effective RLC, and Application Channel Throughputs

• Peak RLC, Effective RLC, and Application Throughputs averaged per User • Peak RLC, Effective RLC, and Application Cell Capacities

• Peak RLC, Effective RLC, and Application Aggregate Cell Throughputs

• Peak RLC, Effective RLC, and Application Allocated Bandwidth Throughputs (UL)

Point Predictions

(20)

Introduction

Principles of the studies based on traffic

Study calculated for

• Given load conditions • UL noise rise • DL traffic load • A non-interfering user with

• A service • A mobility

• A terminal type (in case of a directive antenna , it is oriented towards the serving cell)

(21)

Load Conditions

Load conditions are defined in the cells table

Values taken into consideration in

predictions for each cell

(22)

Service Properties

Parameters used in predictions

Highest bearers in UL and DL

Body loss

Application throughput parameters

(23)

Mobility Properties

Parameters used in Predictions

Mapping between mobilities and thresholds in bearer and quality indicator determination (as

radio conditions depend on user speed).

(24)

Terminal Properties

Parameters used in Predictions

Minimum & Maximum terminal power

Gain and losses

Noise figure

Antenna settings (incl. MIMO support)

Number of Antenna ports in UL and DL in case of MIMO

support

© Forsk 2011 Confidential – Do not share without prior permission Slide 24 of 82

Support of MIMO Min & Max

Power + Noise Figure +

(25)

Prediction Settings

Coverage Prediction Plots

Standard predictions

• Best server plot

• Coverage by signal level • Multiple server coverage

Reference signal, SS, PDSCH, PBCH, PDCCH and PUSCH/PUCCH signal level and quality

predictions

• Selection of a mobility, a service, a terminal (possibly directional antenna oriented towards the serving cell)

• Reference signal, SS, PDSCH, PBCH, PDCCH and PUSCH CNR plots

• RSRP (Average Reference Signal Level Received Power per Subcarrier) plots

(26)

Prediction Settings

Coverage Prediction Plots

CINR, Throughput and Quality Indicator predictions

• Based on user-defined cell loads or on Monte-Carlo simulation results

• Selection of a mobility, a service, a terminal (possibly directional antenna oriented towards the serving cell)

• RSSI – Received Signal Strength Indicator and RSRQ – Reference Signal Received Quality • Reference Signal, SS, PDSCH, PBCH, PDCCH and PUSCH/PUCCH CINR and interference plots • UL Allocated Bandwidth, UL Transmission Power)

• Best bearer plots based on PDSCH and PUSCH CINR levels

• Throughput and cell capacity per pixel plots based on PDSCH and PUSCH CINR levels • Peak RLC, effective RLC, and application channel throughputs

• Peak RLC, effective RLC, and application throughputs averaged per user • Peak RLC, effective RLC, and application cell capacities

• Peak RLC, effective RLC, and application aggregate cell throughputs

(27)

Fast Link Adaptation Modelling

Atoll determines, on each pixel, the highest bearer that each user can obtain

No soft handover

Connection to the best server in term of reference signal level (C)

Bearer chosen according to the radio conditions (PDSCH and PUSCH CINR levels)

Process : prediction done via look-up tables

© Forsk 2011 Confidential – Do not share without prior permission Slide 27 of 82

Best Server Area determination (min RSRP)

Radio Conditions estimation (PDSCH and PUSCH CINR

calculation)

Throughput &

Quality Indicator (BER and BLER) predictions

Reference Signal Level (C) evaluation

(28)

Interference Estimation

Atoll calculates PDSCH and PUSCH CINR according to:

The victim traffic (PUSCH or PDSCH) power

The interfering signals impacted by:

• The interferers powers

• The path loss from the interferers to the victim • Antenna gain

• Losses from interferers (incl. Shadowing effect and indoor losses)

The interference reduction factor applied to interfering base stations transmitting on adjacent

channels (adjacent channel suppression factor)

The interference reduction factor due to interfering base stations’ traffic load

The interference reduction due to Fractional Frequency Reuse (and consequently the mutual

overlap between the channel fractions of the victim and the interfering base stations)

(29)

Prediction Examples (General Studies)

Coverage by signal level

(Based on reference signal power)

Number of servers

(Based on reference signal power)

(30)

Prediction Examples (Dedicated Studies)

© Forsk 2011 Confidential – Do not share without prior permission Slide 30 of 82

Coverage by PDSCH CINR

(Isotropic receiver antenna)

Coverage by PDSCH CINR

(Directional receiver antenna)

(31)

Prediction Examples (Dedicated Studies)

© Forsk 2011 Confidential – Do not share without prior permission Slide 31 of 82

Coverage by PUSCH CINR

(Isotropic receiver antenna)

Coverage by PUSCH CINR

(Directional receiver antenna)

(32)

Radio Reception Diagnosis at a Given Point : Reception Analysis

Point Analysis Tool: Reception

© Forsk 2011 Confidential – Do not share without prior permission Slide 32 of 82

Choice of UL&DL load conditions : if (Cells Table) is selected  Analysis based on DL load and UL noise rise from cells table

Definition of a user-definable “probe" receiver, indoor or not

Cell bar graphs (best server at the top)

Analysis detail on reference signals, PDSCH and PUSCH Reference Signals, PDSCH and PUSCH availability (or not) Selection of the value to be

displayed (RS, SS, PDSCH, RSRP)

(33)

Radio Interference Diagnosis at a Given Point : Interference Analysis

Point Analysis Tool: Interference

© Forsk 2011 Confidential – Do not share without prior permission Slide 33 of 82

Choice of UL&DL load conditions :

if (Cells Table) is selected  Analysis based on DL load and UL noise rise from cells table

Definition of a user-definable “probe" receiver, indoor or not

Selection of the value to be displayed (RS, SS, PDSCH, RSRP) Serving Cell (C) Total Level of Interference (I + N)

(34)

Training Programme

1. LTE Planning Overview

2. Modelling a LTE Network

3. LTE Predictions

4. Frequency and PCI Plan Analysis

5. Monte-Carlo Based Simulations

(35)

4. Frequency Plan Analysis

Channel and Physical Cell ID Search Tools

Physical Cell ID Allocation Audit

Physical Cell ID Histograms

(36)

Search Tool Overview

Tool to visualise channel and PSS ID reuse on the map

Possibility to find cells which are assigned a given :

• Frequency band + channel • Physical Cell ID

• PSS ID • SSS ID

Way to use this tool

Create and calculate a coverage by transmitter with a colour display by transmitter

Open the “Find on Map” tool available in the Edit menu

(or directly in the toolbar )

(37)

Channel Search Tool

Channel Reuse on the Map

© Forsk 2011 Confidential – Do not share without prior permission Slide 37 of 82

Colours given to transmitters • Red: co-channel transmitters

• Yellow: multi-adjacent channel (-1 and +1) transmitters • Green: adjacent channel (-1) transmitters

• Blue: adjacent channel (+1) transmitters • Grey thin line: other transmitters Frequency band and Channel number Resource Selection

(38)

Physical Cell ID, PSS ID and SSS ID Reuse on the Map

Physical Cell ID Search Tool

Colours given to transmitters

• Red or Grey thin line: if the transmitters carries or not the specified resource value (Physical Cell ID, PSS ID

or SSS ID)

© Forsk 2011 Confidential – Do not share without prior permission Slide 38 of 82

Resource Type and

Value Resource Selection

(39)

PCI Allocation Audit (1/2)

Verification of the allocation inconsistencies

Respect of a minimum reuse distance

Respect of neighbourhood constraints (two neighbour cells must have different PCI)

Respect of SSS ID allocation strategy

(40)

PCI Allocation Audit (2/2)

Audit results

Inconsistencies are displayed in the default text editor

© Forsk 2011 Confidential – Do not share without prior permission Slide 40 of 82

The minimum distance constraint is fulfilled

Cells BRU010_L1 & BRU116_L2 are Neighbour cells but have been allocated

the same PCI

These 13 sites do not fulfil the SSS ID allocation strategy:

on each site, allocated PCI do not have the same SSS ID

(41)

Physical Cell ID Histograms

View of the Physical Cell ID Distribution

Dynamic pointer

(42)

Training Programme

1. LTE Planning Overview

2. Modelling a LTE Network

3. LTE Predictions

4. Frequency and PCI Plan Analysis

5. Monte-Carlo Based Simulations

(43)

5. Monte-Carlo Based Simulations

Traffic modelling

Monte Carlo Simulations

(44)

44

Traffic Modelling (1/2)

Traffic Data

Traffic maps and subscriber lists

Various types of traffic maps:

• Raster traffic maps • Vector traffic maps • Live traffic maps • Traffic density maps

Live Traffic Data

Vector Traffic Data

Raster Traffic Data

Subscribers

(45)

45

Traffic Modelling (2/2)

Subscriber Lists

Lists of subscribers with fixed locations and specific parameters

Can be created using the mouse or imported from txt and csv files

Can be displayed on the map according to different parameters

Main parameters:

• Location: X and Y coordinates • Antenna height

• Azimuth and tilt (user-defined or calculated) • Serving cell (user-defined or calculated) • User profile

• Terminal type

Prediction calculations can be carried out

on subscribers (points)

• Predicted results include reception levels, CINR, throughputs, etc.

(46)

46

Monte Carlo Simulations (1/3)

Monte Carlo Simulations

For studying network capacity

Network behaviour under given traffic

Can be based on traffic data from traffic maps

and subscriber lists

Distribution of mobile users and services

Calculation of user parameters (CINR, power control,

noise rise, resource allocation, etc.)

Scheduling and radio resource allocation

based on service priorities and scheduling methods:

• Proportional Fair • Proportional Demand • Max Aggregate Throughput

(47)

47

Monte Carlo Simulations (2/3)

Simulation Results

For each cell

• UL and DL traffic loads • UL noise rise

• UL and DL aggregate cell throughputs • Traffic input and connection statistics

• …

For each mobile

• Serving transmitter and cell

• Azimuth and tilt (towards the serving cell)

• Reference signal, SCH/PBCH, PDSCH, and PUSCH signal levels

• Reference signal, SCH/PBCH, PDSCH, and PUSCH CINR and interference levels • Best bearers based on PDSCH and PUSCH CINR levels

• Cell throughputs, cell capacities, and user throughputs PDSCH and PUSCH CINR levels • Connection status and rejection cause

(48)

48

Monte Carlo Simulations (3/3)

(49)

References

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