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Atoll User Guide

Before Using Atoll We need some preparation before using Atoll to do the planning or simulation, as listed below:  Digital map data; including DTM, clutter, vector data, road map, etc  Site information data; which is including the site name, longitude, latitude, antenna height, antenna azimuth (bearing), frequency and BSIC for GSM simulation, antenna tilt etc  Antenna data; this includes the vertical/horizontal polarization, gain, and beamwidth. We can download this data from the antenna manufacturer website.  Equipment data; such as feeder length, feeder loss, equipment (BTS) transmit power, etc, which is needed to do link budget simulation.

Atoll Installation 1. Start Atoll installation by running the Atoll.us.2.8.0.2808.exe and follow the instructions. You must restart your computer after the installation. 2. Copy Sx32w.dll into C:\Program Files\Forsk\Atoll after you restart the computer. 3. Atoll should be working now.

Starting Atoll Project – GSM/GPRS This guide will cover how to start GSM project. Below is detailed explanation: 

Start Atoll and choose File -> New -> From a Document Template. Choose one of the Project Templates according to your project. In this case we will use GSM GPRS EGPRS template.

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Before we start importing such as digital map or site info data we have to set the coordinate and its format. Go to Tools -> Options. The Options dialogue box will appear.

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We must choose the right Projection and Display (coordinate system) in order to get the correct position of the map and the sites. For Projection and Display coordinate system you must refer to the README file of the map you’re using. They usually provide the coordinate system in that file (for example: WGS50 North hemisphere). Practically, you might need to do some experiment with some projection until you find the correct one (in case the map don’t provide you with this.

Importing Digital Map Data   

We assume in this case we have three digital map, which are: Clutter, Height, and Vector. Go to File -> Import to open the digital map file. In the File of type choose Planet ® Database. The Planet data to be imported will appear. Locate the DTM, clutter, and vector index files and make sure it use the correct projection. After succesful imports, the file will be listed in the Geo tab in the Explorer window.

Importing Antenna Data Before we can work with the sites or do the simulation, we must specify the equipment that would be used with the network. One of the equipment is the antenna. The type of the antenna, the gain, the manufacturer, will affect the simulation in radio environment. Below is the step of how to import the antenna:  First, you need to specify the Antenna type for each site by make sure they exist in the cell file.  From the cell file we can go to the manufacturer website to download the antenna radiation pattern. For Andrew antennas you can go to http://www.commscope.com/andrew/eng/index.html. For Kathrein, you can find them in http://www.kathrein-scala.com/library/rplib/index.php. The easiest way is to download the Planet format. It’s basically a text document and you can open it by Excel. In this file, we can find the manufacturer, operating frequency, horizontal/vertical beamwidth, gain, and the radiation power for each angle (vertical & horizontal).

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To import or create the antenna in Atoll, right click in the Antenna in the Explorer bar and select New.

Creating new antenna and Antenna Properties

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Antenna properties dialogue box will appear, fill it according to the downloaded antenna pattern files. Be careful with the Gain value. Make sure the value in the file is already in dBi, if it is not then convert it by dBi = dBd + 2.15. To fill the Horizontal Pattern, first we have to copy the radiation pattern (0 - 360˚) from downloaded antenna file. Paste the 360 degree pattern into Co-Polar Section according to the Angle and Att. Please make sure you click in the red square before paste.

Copy from antenna file

Click in the red rectangle and paste

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The Vertical Pattern is the same with the horizontal. For the beamwidth in the Other Properties, fill it according to the value from antenna file (such as 65 or 90 deg). After that confirm it by clicking OK. The antenna names will then appear in the Antennas data tab. We can check it by double-clicking the Antenna name, below is the example (65 deg Andrew antenna) :

Importing Site Info Data     

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We can use the existing site info data to be imported in Atoll. The easiest way is to save the site info in TXT or CSV format so Atoll can read it. Prepare your site info data (XLS) and save it into TXT or CSV. Make sure all the important parameters are included in the file. Go to the Data tab in the Explorer window and right click in the Sites. Choose Open Table. Right click in the window that appear and choose Import. Locate the TXT files containing the site info and open it. The Import dialogue box will appear. Do some correction in the Field Mapping box by checking the Source and Destination, whether it’s needed or whether it’s being mapped to the correct column. We can ignore the other unused column. Atoll will not import those ignored column. Please note, that in this step the most important things is the SiteName (Name) and the Longitude/Latitude column (they must be exist), while the rest can be ignored.

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After check all the column, click Import. The sites should be plotted correctly in place. If it’s not, then make a check at the Coordinate System setting. You can (optionally) do some configuration with the appearances of the sites. Simply right click in the Sites in the Explorer bar and choose Properties. Then you can modify the font, symbol, etc in the Display tab.

Importing the Transmitter Data     

In Atoll, importing Site is just importing the site location or position. The rest parameter such as antenna, frequency plan, azimuth, etc must be imported into the Transmitters. Go to the Data tab and right click at the Transmitters, choose Open Table. Right click in the new window and choose Import. Locate your TXT/CSV file and open it. The Import dialogue box will appear. Do some correction in the Field Mapping box by checking the Source and Destination, whether it’s needed or whether it’s being mapped to the correct column.

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Below is the most important column that is needed for simulation in Atoll. You can also find the explanation. Make sure these columns exist in your cell info.

Column Site Transmitter Active Antenna Height (m) Azimuth (deg) Mechanical Downtilt (deg) Additional Electrical Downtilt (deg) EIRP (dBm) Power (dBm) Losses (dB) Feeder Equipment Transmission Feeder Length (m) BCCH BSIC

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Explanation The site name e.g. 161001 CellName or sector e.g. 161001_1 On air status Antenna type, must be listed in the Antenna data tab Antenna height Azimuth or bearing MDT EDT Antenna EIRP BCCH power Leave this blank, calculated later Feeder diameter e.g. 7/8" Height + 5 (m) BCCH ARFCN BSIC=NCC+BCC

After the entire Transmitter is correctly imported, we can make some adjustment to the sites appearance by right click at Transmitters and choose Properties. Go to the Display tab in the Transmitters properties dialogue box. Choose Automatic in Display type and we can change the transmitter display by clicking in the cells that contains arrow image. One case if your cell info data contain BCCH power or BTS power, then this column must be mapped into the Power (dBm) in Atoll. But, if the power not appears after importing

then we should do this. First, import the BCCH power from the cell file as EIRP (dBm). Then click in the EIRP (dBm) column header and Ctrl+C. Second, click Power (dBm) column header and Ctrl + V.

Copy data from EIRP (dBm) and paste in Power (dBm) 

After the import success, we must calculate the Losses. Right click in the Transmitter and select Equipment -> Recalculate Losses. We can check the

Propagation Model This guide assumes that the propagation model is uniform in the entire network. However in the real case the propagation model should be different according to the clutter type: urban, suburban, or rural. The commonly used propagation model is Okumura – Hata. Below is how to set Okumura-Hata as the propagation model.  Right click in the Transmitter and select Properties.  In the Propagation tab, select Okumura-Hata in the Main Matrix; Propagation Model drop-down list.

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Change the Radius or Resolution depends on the simulation and digital map resolution.

COVERAGE AND INTERFERENCE SIMULATION 

Go to the Explorer bar, Data tab, and right click in Predictions. Select Properties.

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Choose the Default Propagation Model and Default Resolution. Confirm it by clicking OK. Right-click in the Predictions and select New.

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Select Coverage by Signal Level in Study Types then confirm it by OK. The new dialogue box will appear. In the General tab fill the Name and Resolution according to your previous setting.

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In the Condition tab, set the parameter as below: o Server : Best Signal Level o Shadowing taken into account : checked o With a margin : 4 dB or own setting o Indoor Coverage : checked in the urban/suburban simulation o Cell Edge Prob : 90% for dense city, 85% other o Reception from Subcells : BCCH

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In the Display tab choose Display Type: Value intervals and Field: Signal Level (dBm). We can modify the range and color using the Actions button to match with the operator needs. Confirm by OK. The new prediction should appear under the Predictions. Right-click in the new prediction and select Calculate. Atoll should be starting to calculate and might take several minutes to complete.

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Coverage simulation

Interference Simulation (C/I)  

Right click in the Predictions and select New. In the Study Types dialogue box select Coverage by C/I Level.

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Fill the Name and Resolution according to your previous setting.

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In the Condition tab, set the parameter as below: o Server : Best Signal Level o Shadowing taken into account : checked o With a margin : 4 dB or own setting o Indoor Coverage : checked in the urban/suburban simulation o Cell Edge Prob : 90% for dense city, 85% other o Interfered Subcells : BCCH

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Display tab: we can adjust it according to the operator needs.

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The new prediction should appear under the Predictions. Right-click in the new prediction and select Calculate. Atoll should be starting to calculate and might take several minutes to complete.

Interference simulation