Atoll 3.1.2 Automatic Cell Planning Module.pdf

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Automatic Cell Planning Module Atoll 3.1.2

1. Introduction

2. Parameters Used by ACP

3. Network Reconfiguration Process

4. Site Selection Process

5. Other Topics


Training Programme

1. Introduction

Automatic optimisation tool for GSM, UMTS, CDMA, LTE and WIMAX networks

To improve existing networks by tuning parameters that can be easily changed remotely

• Antenna electrical tilt

• Power (BCCH for GSM, Pilot for UMTS, Reference Signal for LTE, Preamble for WiMAX)

To optimise a network still in the planning phase by:

• Selecting antennas

• Changing the antenna azimuth

• Changing the mechanical downtilt of the antenna

• Changing the antenna height

• Selecting sites among a list of candidate sites

Combined GSM/UMTS/LTE optimisation can be performed


1. Introduction

Principle

Optimisation of quality indicators

By automatic adjustments of network parameters

• Power (BCCH for GSM, Pilot for UMTS/CDMA, RS for LTE and Preamble for WiMAX)

• Antenna parameters:

• Type of antenna

• Azimuth

• Mechanical downtilt

• Electrical downtilt

• Height


GSM

• BCCH coverage

• Dominance of Best Server

UMTS/CDMA

• RSCP (Pilot) coverage

• CPICH Ec/Io

LTE

• Reference Signal coverage

• Reference Signal CINR

WIMAX

• Preamble coverage

• Preamble CINR

1. Introduction

Principle

Optimisation process based on a cost function

The cost function depends on quality figures

• In GSM: the cost decreases when the BCCH coverage and the Best Server’s dominance increase

• In UMTS/CDMA: the cost decreases when the Pilot coverage and Pilot quality increase

• In LTE: the cost decreases when the RS coverage and RS CINR increase

• In WIMAX: the cost decreases when the Preamble coverage and Preamble CINR increase

Iterative algorithm is used

• Each iteration corresponds to one network parameter change

• Then, changes are ranked from the change with the most benefit to the change with the least benefit


1. Introduction




5. Other Topics


Training Programme

2. Parameters used by ACP

Requirements

Existing and valid path loss matrices

Recommendations

Creating a Computation Zone

• Used to define the default area where the ACP calculates statistics on performance indicators

Creating a Focus Zone

• Used to define the default area in which are the cells to be optimised


Computation zone

= Zone used to compute statistics on performance indicators (by default)

Focus zone

= Area where the optimisation will be performed (by default)

1. Introduction




5. Other Topics


Training Programme


Creating an Optimisation Setup

Defining Optimisation Parameters and Objectives

Running an Optimisation Process

Viewing Optimisation Results

Analysing Optimisation Results


Creating an Optimisation Setup


To run the optimisation immediately

To save the defined optimisation parameters and run the optimisation later

Defining Optimisation Parameters (1/9)

Selection of layers to be optimised


Layer(s) configuration Several in case of Multi-RAT networks (GSM+UMTS+LTE)


Selection of zones to be optimised


Zones definition

Possibility to define zones to be specifically optimized, using:

• Clutter Classes,

• Hot Spots zones,

• .shp files


Choice between quality or financial cost based optimisation


No cost control: the optimisation is only based on quality

Useful when planning a new network

Possibility to limit the financial cost of the optimisation:

• Maximum financial cost allowed • Compromise between the financial cost and the quality

Useful when improving an existing

network

Definition of the financial cost for: • Each parameter change • Each site visit • etc...


Selection of transmitters/cells to be optimised

Definition of parameters that can be modified by ACP


To define Cells’ Optimisation parameters (Subcells power in GSM, Pilot power in UMTS, RS power in

LTE and Preamble power in WiMAX)


By default, GSM-UMTS-LTE transmitters sharing the same antenna parameters are linked

An auto-Link function based on site coordinates, antenna height, azimuth and mechanical tilt is provided



Definition of Antenna Groups

To give some directives when reconfiguring the antenna type or the electrical tilt


Multi band “Physical Antenna”

Dual 900 1800 – 65deg17dBi Multi band “Physical Antenna”

Dual 900 1800 – 36deg20dBi

Antenna Element 65deg17dBi@900

Antenna Element 65deg17dBi@1800


Step 1 : Create “Antenna Element” (using radiating patterns)


• An “Antenna Element” is defined by one gain, one

beamwidth and one frequency band

• For a given frequency band, a given beamwidth and a given

gain, the “Antenna element” is a group of antenna patterns

obtained with different electrical tilt values

Antenna patterns table


Step 2 : Create “Physical Antennas” (using Antenna Elements)

To define multiband antennas


Multi band “Physical Antenna”

Antenna Elements


Step 3 : Create “Antenna Groups” (using Physical Antennas)

To define groups of Physical Antennas that will be then assigned to transmitters in the reconfiguration tab


Antenna groups to be assigned to TXs in the Reconfiguration tab

Created Physical Antennas

Defining Objectives (1/11)

ACP allows you to define Quality and Coverage objectives for each technology

Objectives are assessed over a “Target Zone” (Computation Zone, by default)


Objectives defined by the user Indicators to be optimized


Objective & Zone weighting

Objectives and Zones can be weighted according to their relative importance


Give priorities to specific Zones *

(* Priorities only apply if the “Zone Weighting” option is checked)

Give a priority to each objective


Traffic weighting (per objective)

ACP is able to focus more specifically on areas with a high traffic


Default option: NONE the traffic is assumed to be uniform

The quality indicator measured on each pixel has the same weight

Selection of traffic maps (non-uniform traffic) to weight map pixels

The quality indicators measured on each pixel can be weighted by using the traffic density on that pixel


Example: Defining UMTS objectives

Coverage objectives : UMTS RSCP Coverage


Define the Minimum Pilot Signal Level to

get on each pixel of the

“Target Zone”

Coverage to be respected while

meeting the RSCP coverage

conditions



Quality objectives : UMTS EcIo


Define the Minimum Pilot Quality to get on each pixel of the “Target

Zone”

Coverage to be respected while

meeting the Pilot Quality

conditions



UMTS Objectives Parameters

For each indicator to optimize, ACP settings (display configuration, shadowing margin…) can be:

• Either, taken from an existing prediction

• Or, defined manually



Summary of the indicators that can be optimized for each technology


GSM

• BCCH coverage

• Dominance of Best Server (= Number of potential servers must be < 4)

UMTS/CDMA

• RSCP (Pilot) coverage

• CPICH Ec/Io

• Pilot Pollution (= Number of cells in the Active Set > 3)

LTE

• Reference Signal coverage (or RSRP)

• Reference Signal CINR (or RS C/N, RSRQ)

• Overlap (= Number of potential servers must be < 4)

WIMAX

• Preamble coverage

• Preamble CINR

• Overlap

Load balancing (Optional)

ACP enables you to create and manage capacity planning objectives

• To prevent load imbalance between sectors and thus avoid the degradation of some KPIs

Example: Optimisation of a UMTS network by ACP without Load Balancing

The Load balancing feature relies on 2 performance indicators:

• The “Average Load” improvement (%), measures how the average load improves from the initial value

• The “Load Balance” (%), measures the dispersion of cells loads



Cell A: Up-tilt (2°)

Cell B: Down-tilt (1°)

• Traffic served

• Cell load

- DL Total Power

- UL Noise Rise

• Interference

• Risk of congestion

Cell Load A = 75% ; Cell Load B = 60%

Solution: Load Balancing !

Cell A Cell A

Cell B Cell B

Cell Load A = 98% ; Cell Load B = 45%

(Statistics on Cell A)



Can be activated in the “Objectives” tab under “Load Balancing”


Recommendation: Keep the default

configuration

Allows you to select the layers for which load

balancing is performed



Traffic related to capacity planning can be defined in the “Capacity” tab


Traffic can be considered as uniform (evenly spread on each

service area) or, generated from traffic

maps



ACP is designed to perform load balancing across multiple layers and technologies


For each service used, traffic is balanced across

all the available layers and technologies

For each service and

each technology, define the minimum quality required by a cell to provide the service

To increase traffic density specifically on some

zones. Traffic is scaled according to the weights

defined in the “Zone Weighting” tab.

Running an Optimisation Process (1/4)

Graphical display of the optimisation progress

“Graphs” tab: Variation of performance objectives in real time with iterations


The optimisation process can be paused or stopped early



“Changes” tab: Type and number of changes




“Quality” tab: Coverage and Quality improvements (variations)




“Objectives” tab: To see at a glance if the objective is achieved or not


Select the objective to be

analysed (coverage and

quality indicators)

Viewing Optimisation Results (1/5)

Optimisation results are stored in the optimisation folder

Results available in 7 tabs

“Statistics” tab: synthesised view of optimisation results for each objective

Statistics provided for the “Target zone”

• To get statistics on the other zones select “Show Detailed Zone Results”


Statistics for each objective

Global report available in “Excel” format


“Graph” and “Quality” tabs


Histogram displaying statistics within the computation zone or the focus zone

Coverage and Quality maps before and after the optimisation


“Capacity” tab

Provides capacity load statistics for the initial and the optimised network


The graph shows the ratio of cells with a capacity load that is smaller

than a given capacity load value (%).

Usually, the best result that you can get is a final curve (blue curve) on top of the initial curve (red curve).

Statistics based on the values displayed in the table (on the right)


“Change Details” tab

Analysis of improvements according to the number of changes

Changes are ordered by “profitability”

• The most “profitable” changes will be applied first


Slider to select a subset of all changes and view the corresponding

performance improvement on the graph (global improvement and improvement of each objective)

List of changes ranked from the change with the most effect to the change with

the least effect

Selected changes are displayed in green


“Commit” tab

To commit changes that you allowed in the “Change Details” tab


Transmitters/cells with parameter changes are

displayed in green

Initial and final cell parameters displayed

Revert the network to its state before the optimisation was run

Apply the set of selected changes

Analysing Optimisation Results (1/5)

Process

Quick validation of optimisation results using the ACP maps

• First analysis available without having to commit ACP results

• Based on the entire set of proposed changes

Deeper analysis with coverage predictions available in the predictions folder

• After committing ACP results

ACP Maps Available

Quality analysis maps

• Display of Coverage and Quality maps

Coverage analysis

• Status of the coverage according to the defined objectives used in the optimisation

Change analysis

• Analysis of changes: antenna, tilt, azimuth

Best server analysis

• Absolute values of changed parameters



Analysis with ACP Maps


ACP maps are automatically calculated and inserted into

the folder containing the optimisation results



Tiptext available for any ACP map

• The exact calculated value is displayed on each pixel

Display properties of ACP maps

• Automatic update of the ACP map after changing colours or range of values




Histogram available on ACP maps

Comparison tool

• Available to compare ACP maps from the same optimisation or from a different optimisation



Analysis with coverage predictions from the predictions folder

Requirement: Commit results of the optimisation

Calculating prediction studies before and after the optimisation

Generating reports on the predictions studies before and after the optimisation in order to check if network quality figures have been improved

Possibility to “Roll back to Initial State”


1. Introduction




5. Other Topics


Training Programme


Overview

Defining Candidate Sites

Viewing Optimisation Results


Overview (1/2)

Examples of Site Selection process

Scenario 1: using ACP to select the best site among several candidates on a given geographical area

• 3 candidate sites available

• Candidate sites are assigned to a group where the minimum and the maximum site occurrence is set to “1”

Among the 3 candidates, the ACP is forced to select only one site

Scenario 2: using ACP to deploy the LTE technology on a given area using existing UMTS sites

• About 40 UMTS sites (i.e. 40 candidate sites) available on the target area

• Candidate sites are assigned to a group where the minimum site occurrence is set to “10” and the maximum to “20”

Among the 40 candidates, the ACP is forced to select between 10 and 20 sites to reach objectives


Overview (2/2)

General process similar to the site reconfiguration process:

Creating an optimisation setup

Defining “Candidate” sites

Defining objectives and parameters to be optimised

• Note: The “Reconfiguration” mode is available (not mandatory) during the Site Selection process.

Running an optimisation process

Viewing optimisation results

Analysing optimisation results


Defining Candidate Sites (1/3)

By using pre-defined sites

Prerequisite: Stations to be processed by ACP must be defined in the Atoll document with a given status


Two status for sites:

• “Existing”:

The site is an active site in the current network. ACP can remove the whole site or

one or more sectors of the site to improve the network quality

• “Candidate”:

The site is not on-air in the initial network (i.e. all TXs are deactivated). ACP can add the site

or only one or more sectors of the site to improve the network quality

Check “Current Site Selection” to allow changes (site / sector removal) among “existing” sites

Check “Current Site Selection” to display deactivated sites. Then, define groups of sites with a min. and a max. number of sites to be

added during the optimisation (“Group” column)


By using pre-defined sites


“Advanced” tab:

Allows you to apply the same locking options to a set of sites,

and to manage groups

“Reconfiguration” column:

Select “Disable” to prevent ACP from making any changes to the Transmitters or to the Cells,

as defined in the Transmitters and the [Technology] Cells tabs

In case of network reconfiguration, you can preserve the current angular separation

between antennas, and the relative height difference between them


By importing a list of candidate sites


Option 1: import a text file (*.txt) containing at least candidates’ name and coordinates

Option 2: import a list of candidate sites from the Atoll project

To allocate a station template to each candidate site

Viewing Site Selection Results (1/3)

Statistics Report


Statistics and status of the optimisation (Achieved or Failed) for each objective

Select “Show Change Statistics” to get statistics on the sites/sectors added or

removed, and all the changes made during the optimisation process


Implementation Plan Analysis


Sites/TXs/Cells added or removed

List of changes (antennas, tilts, etc.) if “Reconfiguration” mode selected


Transmitters/Cells Modifications Analysis


List of candidate TXs/cells to be added

List of TXs/cells to be removed

List of changes (antennas, tilts, etc.), if “Reconfiguration” mode

selected

1. Introduction




5. Other Topics


Training Programme

6. Other Topics

Combined GSM/UMTS/LTE Optimisation (in case of several .atl documents)

Data Loading and Validity Control

Saving Settings to Configuration Files

Configuring Default Settings


Combined GSM/UMTS/LTE Optimisation (1/2)

Requirements (in case of several .atl documents)

Several Atoll projects (GSM, UMTS and/or LTE .atl files) that must be opened in the same Atoll session

General process similar to a classic optimisation

Creating the optimisation setup

Defining optimisation parameters

Running the optimisation process

Viewing optimisation results

Analysing optimisation results


Combined GSM/UMTS/LTE Optimisation (2/2)

Procedure (in case of several .atl documents)

Step 1: Create the optimisation setup in one single technology document (a LTE document for ex.)

Step 2: Import other(s) network(s)’ configuration by importing associated project(s)


Data Loading and Validity Control (1/2)

Data used when running an optimisation process

Radio data (antennas, sites, transmitters)

Traffic parameters (services, terminals, etc.)

Geographic maps (DTM, clutter class and clutter height maps)

Traffic maps

Path loss matrices


Loaded when creating an optimisation setup

Direct access when running the optimisation process

Data Loading and Validity Control (2/2)

Data validity control when running an optimisation process

Atoll checks the consistency between the optimisation setup, the actual state of the network and path loss matrices

If inconsistencies => existing optimisation setups are locked and new optimisation process cannot be run

Incoherence with existing setup when:

Data changes are performed after creating the setup (e.g. New transmitter, transmitter deactivated, different transmitter settings, etc.)

Optimisation results have been committed

Path loss matrices are missing or not valid


Saving Settings to Configuration Files

Save or load a given Setup Configuration


Optimisation settings saved in a .PRJ file (objectives per clutter class, lists of cells

to be reconfigured, reconfiguration settings, etc.)

Import the configuration file containing optimisation settings

Used to apply the same settings when you create a new optimisation setup

Configuring User Preferences


Trade-off between speed and quality

Enables you to activate the “Multi-Storey” and

the “EMF Exposure” extensions

Setup Template Configuration


Define default values of the Optimisation Setup

Configuring Path Loss Matrices Storage


Define the folder to be used by ACP to store Path Loss Matrices

(used in case of Antenna Height optimisation)


Thank you

Documents

Atoll 3.1.2 Automatic Cell Planning Module.pdf