propagation model tuning in ics telecom - atdi · propagation model tuning in ics telecom page 5 of...
TRANSCRIPT
PROPAGATION MODEL
TUNING in ICS Telecom
ADVANCED
TOPOGRAPHIC
DEVELOPMENT
& IMAGES
SOFTWARE DESIGNERS: P & D MISSUD
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 2 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
VERSIONS HISTORY
Version Date Writer
PROPAGATION MODEL TUNING in ICS Telecom
version
Remarks
1.0 14/11/2013 GALAS
Jarosław 12.2.6
The present version of the document covers the features available in the release v.12.3.6. This document will be upadted at regulars intervals to ensure that it considers the latest uptates of ICS Telecom.
Limited Warranty
This manual is subject to the limited warranty conditions as specified by the general operating license of the whole package. ATDI reserves the right to modify this manual without prior warning.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 3 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
TABLE OF CONTENTS Versions History .................................................................................................................................... 2
Table of Contents ................................................................................................................................. 3
1. Scope .............................................................................................................................................. 4
2. Propagation model tuning ........................................................................................................... 4
2.1. Clutter tuning .......................................................................................................................... 4
2.1.1. Configuration of Clutter tuning ..................................................................................... 4
2.1.2. Clutter tuning report and results .................................................................................. 6
2.2. Subpath tuning ....................................................................................................................... 7
2.2.1. Configuration of Subpath tuning .................................................................................. 7
2.2.2. Subpath tuning report and results ............................................................................... 9
3. Example ....................................................................................................................................... 11
3.1. Project setup ........................................................................................................................ 11
3.1.1. Cartographic data ........................................................................................................ 11
3.1.2. Base station configuration .......................................................................................... 12
3.1.3. Base configuration of clutter and propagation model ............................................. 12
3.2. Measurements data ............................................................................................................ 14
3.2.1. Conversion factor for measurements ........................................................................ 14
3.3. Propagation model tuning .................................................................................................. 15
3.3.1. Correlation before model tuning ................................................................................ 15
3.3.2. Clutter tuning ................................................................................................................ 16
3.3.3. Subpath tuning ............................................................................................................. 18
3.3.4. Conclusion .................................................................................................................... 20
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 4 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
1. SCOPE Designing a network using a planning tool is meaningful as soon as the results obtained can be considered as reliable. The ATDI Planning tool provides dedicated functions for:
- comparison of the measurement data (drive tests, punctual measurements…) and the prediction, - tuning propagation model.
This paper will detail a new automated propagation model tuning functions .
With this new function it is possible to tune propagation model in a two different ways:
- clutter tuning (diffraction factor, clutter attenuation in dB, clutter attenuation in dB/km), - modify subpath attenuation calculation method.
2. PROPAGATION MODEL TUNING
2.1. Clutter tuning
The new clutter tuning function is available in the menu ‘Measure � Tuning � Measurements…’
2.1.1. Configuration of Clutter tuning
Figure 1: Clutter tuning – generic format
Measurement file name : The Clutter tuning – generic format function requires a standard ASCII file following the structure: X [Separator] Y [Separator] FS <CR>
Input format : display first line of loaded measurement file
Separator symbol: The type of separator (, ;) can be specified by the user.
X and Y are inverted : should be checked when the X and Y coordinates are inverted in the measurement file
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 5 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Coordinate code: it is specified by the user, enabling the measurement file to be compatible with any coordinate code handled by the ATDI tools.
Conversion to dBu (+-dB) : this applies an offset to measured values, in order to convert them into dBµV/m (conversion from dBm values into dBµV/m for instance)
Min range (measurement) : The user can define minimum value of measurements that will be taken into account. This value can be updated from measurement file by clicking upd button
Max range (measurement): The user can define maximum value of measurements that will be taken into account. This value can be updated from measurement file by clicking upd button
Threshold (dBu): The user specifies a value in dBµV/m below which all measured values will not be imported on screen
Rx antenna height (m): receiving antenna height in m used during measurements
Number of values : display number of values in measurement file. This value can be updated from measurement file by clicking upd button
Set clutter to 0 on measurement point : clutter code in the location of the measurement point is modified to code 0. Measurement point is considered as open area
Move measurements on vector line : if a vector line is present, the measurement point will be relocated on the vector line.
Clutter selection (tuning) : in this box the user can define which clutters will be tuned
Choice of clutter parameter to be tuned:
Clutter height tuning (diffraction factor): with this option clutter tuning function will tune clutter height (diffraction factor) parameter. The user need to set: minimum diffraction factor, maximum diffraction factor and step.
During the clutter height tuning for a given measurement point program will calculate coverage for each clutter code with a diffraction factor (from a given range, with a given step) and compare it with measurements.
Clutter attenuation tuning (dB): with this option clutter tuning function will tune clutter attenuation (dB) parameter. The user need to set: minimum attenuation (dB), maximum attenuation (dB) and step (dB).
During the clutter attenuation tuning (dB) for a given measurement point program will calculate coverage for each clutter code with a clutter attenuation (dB) (from a given range, with a given step) and compare it with measurements.
Clutter attenuation tuning (dB/km): with this option clutter tuning function will tune clutter attenuation (dB) parameter. The user need to set: minimum attenuation (dB/km), maximum attenuation (dB/km) and step (dB).
During the clutter attenuation tuning (dB/km) for a given measurement point program will calculate coverage for each clutter code with a clutter attenuation (dB/km) (from a given range, with a given step) and compare it with measurements.
From Clutter tuning – generic format dialog box user has also access to clutter parameters, propagation model selector, calculation distance, station list.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 6 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
2.1.2. Clutter tuning report and results After the clutter tuning function finish calculations Report listing window appear:
Figure 2: Clutter tuning – Report listing
The report list for each clutter code and for tuned parameter (from min/max range):
- Mean delta (dB): mean delta in dB between measurements and prediction for a given clutter code and value of tuned parameter
- Pc < 6 dB : percent of values (delta between measurements and prediction) that are lower than 6 dB for a given clutter code and value of tuned parameter
Report can be exported to CSV file by Listing button.
Result of clutter tuning:
Clutter tuning function will automatically update clutter parameters (Diffraction factor, Attenuation (dB) or attenuation (dB/km) according to the best Pc < 6 dB results.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 7 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 3: Clutter parameters. Diffraction factor after clutter tuning
2.2. Subpath tuning
2.2.1. Configuration of Subpath tuning The new subpath tuning function is available in the menu ‘Measure � Tuning � Subpath methods…’
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 8 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 4: Subpath tuning – generic format
Measurement file name : The Clutter tuning – generic format function requires a standard ASCII file following the structure: X [Separator] Y [Separator] FS <CR>
Input format : display first line of loaded measurement file
Separator symbol: The type of separator (, ;) can be specified by the user.
X and Y are inverted : should be checked when the X and Y coordinates are inverted in the measurement file
Coordinate code: it is specified by the user, enabling the measurement file to be compatible with any coordinate code handled by the ATDI tools.
Conversion to dBu (+-dB) : this applies an offset to measured values, in order to convert them into dBµV/m (conversion from dBm values into dBµV/m for instance)
Min range (measurement) : The user can define minimum value of measurements that will be taken into account. This value can be updated from measurement file by clicking upd button
Max range (measurement): The user can define maximum value of measurements that will be taken into account. This value can be updated from measurement file by clicking upd button
Threshold (dBu): The user specifies a value in dBµV/m below which all measured values will not be imported on screen
Rx antenna height (m): receiving antenna height in m used during measurements
Number of values : display number of values in measurement file. This value can be updated from measurement file by clicking upd button
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 9 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Set clutter to 0 on measurement point : clutter code in the location of the measurement point is modified to code 0. Measurement point is considered as open area
Move measurements on vector line : if a vector line is present, the measurement point will be relocated on the vector line.
During the subpath tuning for a given measurement point program will calculate coverage with a different subpath methods and compare it with measurements.
From Subpath tuning – generic format dialog box user has also access to clutter parameters, propagation model selector, calculation distance, station list.
2.2.2. Subpath tuning report and results After the subpath tuning function finish calculations Report listing window appear:
Figure 5: Subpath tuning – Report listing
The report list for each subpath model:
- Mean delta (dB): mean delta in dB between measurements and prediction, - Percentage 6 dB : percent of values (delta between measurements and prediction) that are lower
than 6 dB for a given clutter code and value of tuned parameter Report can be exported to CSV file by Listing button.
Result of subpath tuning:
Subpath tuning function will automatically update Subpath attenuation model in Propagation model configuration according to the best Pc < 6 dB results.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 10 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 6: Propagation models. Subpath attenuations model after subpath tuning
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 11 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
3. EXAMPLE Let’s consider an example of propagation model tuning based on WiMAX network.
3.1. Project setup
3.1.1. Cartographic data
Figure 7: From the top let corner: 1m resolution DTM, clutter layer, building layer and BING image layer
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 12 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
3.1.2. Base station configuration Configuration of base station that was used for measurements.
Figure 8: Base station configuration
3.1.3. Base configuration of clutter parameters and propagation model Base configuration of clutter parameters and propagation model used for simulation before model tuning.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 13 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 9: Base configuration clutter parameters
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 14 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 10: Base configuration of propagation model
3.2. Measurements data
Measurements data should be delivered in CSV file with fallowing structure:
X [Separator] Y [Separator] FS <CR>
Sample of measurements:
21.998072;50.034898;-73 21.998212;50.034733;-73 21.998287;50.034645;-73 21.99842;50.034472;-78 21.998485;50.034388;-78 21.998652;50.034193;-80
3.2.1. Conversion factor for measurements If measurements are in dBm unit it is necessary convert it to dBµV/m . Without using this conversion factor it will be not possible to correctly display and use measurements. To calculate conversion factor Field strength converter could be used.
Menu ‘Tools � Field strength converter…’
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 15 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
In this example 12 dB antenna gain was used for measurements.
Figure 11: Field strength converter
Calculated conversion factor is equal to + 136 dB.
3.3. Propagation model tuning
In this example propagation model tuning will be made in a two steps:
- clutter tuning - diffraction factor tuning, - subpath tuning.
3.3.1. Correlation before model tuning Correlation between measurements and prediction before tuning of propagation model. Menu ‘Measure � Correlation � Generic (X Y E)…’
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 16 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 12: Correlation function settings
Figure 13: Correlation results before propagation model tuning
Correlation before model tuning:
- correlation factor is 0.70, - standard deviation is 4.07%, - 78.39% values* < 6 dB (* - delta between measurement and prediction in each point)
3.3.2. Clutter tuning First step in propagation model tuning is clutter height tuning (diffraction factor) for Vegetation layers only.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 17 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Menu ‘Measure � Tuning � Measurements…’
Clutter tuning function is configured as below:
Figure 14: Clutter tuning settings – diffraction factor tuning
After that clutter tuning is finished will automatically create report and update diffraction factor for vegetation layers in clutter parameters. After tuning coverage must be recalculated.
Figure 15: Report from clutter tuning
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 18 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 16: Correlation results after clutter tuning
Correlation after clutter height tuning:
- correlation factor is 0.77, - standard deviation is 3.57%, - 88.19% values* < 6 dB (* - delta between measurement and prediction in each point)
3.3.3. Subpath tuning Second step in propagation model tuning is subpath attenuation methods tuning.
Menu ‘Measure � Tuning � Subpath methods…’
Subpath attenuation method tuning function is configured as below:
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 19 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 17: Subpath tuning settings
After that subpath tuning is finished program will automatically create report and update subpath attenuation method in Propagation model settings. After tuning coverage must be recalculated.
Figure 18: Report from subpath tuning
As it is shown on a picture above, the best correlation is for Subpath attenuation method set to coarse integration. This option is automatically set in propagation model settings.
PROPAGATION MODEL TUNING IN ICS TELECOM
Page 20 of 20 The following manual is copyright protected and remains the exclusive property of ATDI. No part of this manual, in whole or in part, may be copied or reproduced in any way without prior written authorization of ATDI.
Figure 19: Correlation results after clutter and subpath tuning
Correlation after clutter and subpath tuning:
- correlation factor is 0.77, - standard deviation is 3.56%, - 93.97% values* < 6 dB (* - delta between measurement and prediction in each point)
3.3.4. Conclusion As it was shown in this example the best results of propagation model tuning are after bought clutter tuning and subpath tuning.
END OF THE DOCUMENT