Session 5.7
Supporting Network Planning Tools II
by
Roland Götz
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Modern Radio Network Planning Tools
Radio Network Planning Tool
Data Management
Data / Result Output
Network Processor
Interference Analysis
Propagation Prediction
Graphical User Interface
Data Management
Geo Information System
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Data Management
Data Management
What is the Minimum Set of Data you need to perform a
Basic Coverage Prediction?
• Coordinates of the Transmitter
• Radiated Power
• Frequency
• Antenna Pattern
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What other kind of Data have to be managed and Why?
Data describing the Transmitter
Antenna
all technical parameters (power range, frequency range, sensitivity...)
Data describing the Network
Sites
Cells, Sectors, links
neighbouring relations
frequency plans, frequency rasters
Data describing Interfering Networks
same service other operators
other services
in other countries
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Data Management
Data Management
What other kind of Data have to be managed and Why?
for Tool Administration
User / Role
Password
System Layout
Result Data Base
Coverage Maps
Interference Relations
Network Analysis
Libaries
Antenna Equipment
Transmitter Equipment
Receiver Equipment
...
which have been performed in the past
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Example: Microwave Link
Data Management
Gain
Gain
Pathloss
Antenna
EIRP
Feeder Loss
Feeder Loss
Branching Loss
Branching Loss
Connector Loss
Connector Loss
Tx Power
Tx
Device
Site 1
Rx
Receive Level
Site 2
Operator
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Example: Microwave Link
Data Management
Microwave Link
Site A
Site B
Operator A
Operator B
Frequency Raster
Antenna
Receiver
Device
Diversity Antenna
Transmitter
Antenna
Receiver
Device
Diversity Antenna
Transmitter
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Database Concepts
Information Database
Data Management
Information Database
Central DB
Update IDB (area or project status)
Update your WDB (area or project status)
Work Database
Work Database
Client B
Client A
Working Database
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Live
Planning Tool Demonstration
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Data Management
Detailed Data Information
are necessary to perform comprehensive network analysis / optimisations
An comprehensive Data Management
allows keeping all network data in one central data base
makes daily work easier (Libraries)
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Modern Radio Network Planning Tools
Radio Network Planning Tool
Graphical User Interface
Data / Result Output
Network Processor
Interference Analysis
Propagation Prediction
Graphical User Interface
Data Management
Geo Information System
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Spreadsheets
Spreadsheets offer a view on database tables.
Graphical User Interface
All records of the related database table (e.g all sectors) can be edited:
Each row contains
information for one
object e.g Antenna
type, antenna
height, azimuth etc.
for a specific sector
Each column stands for one specific database field e.g Antenna Height
The following options are available to work with spreadsheets
Edit functions
Query Functions
Functions to change the layout of the spreadsheet
Functions for graphical display of the spreadsheet data
Import / Export Functions
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Editors
Editor views allow to edit all data related to a specific object
Graphical User Interface
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Working Window
Graphical User Interface
Menu
Toolbar
Working map
Value display
(status bar)
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Task: Creating new Sites
Graphical User Interface
1. Graphically on a map:
Activate the site tool
Click on a pixel on the map
Co-ordinates from
selected position on map
2. In the site table:
Enter co-ordinates
manually
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Live
Planning Tool Demonstration
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Modern Radio Network Planning Tools
Radio Network Planning Tool
Propagation Prediction
Data / Result Output
Network Processor
Interference Analysis
Propagation Prediction
Graphical User Interface
Data Management
Geo Information System
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Wave Propagation Effects
Propagation Prediction
refraction
tropospheric effects
Atmospheric Absorption Loss
f>10 GHz
free space propagation
Rain Attenuation
f>5GHz
diffraction
scattering
reflection
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Refraction
The refraction of the VHF/UHF signal in the troposphere causes an
enhancement of the radio horizon compared to the geometric horizon
n
1
n
2
θ
Propagation Prediction
Low density
K=1,
homogene Atmosphere
2
θ
K= 4/3 Standard
Atmosphere
High density
1
Earth Radius
0
4
Distance in km
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12
16
20
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Diffraction
Diffraction:
Propagation Prediction
a signal could be received even if there is no line of sight
diffraction means also an attenuation of the wave.
higher frequency -> higher diffraction attenuation.
replace obstacles by Knife-edges
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Reflection
Propagation Prediction
d1 = d + (hR − hT )
d2 = d2T + d2R
2
2
d 2 = d 2 + (hR + hT )
2
d1
hT
θi
d2T
θr
d2R
hR
εr
d
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Scattering
Propagation Prediction
from point
from rough surface
Ei
from volume
Ei
Ei
Es
analytical model for sphere
numerical techniques
Es
Es
modified reflection coefficient
radiative transfer theory
statistical models
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Wave Propagation Models VHF/UHF
Modern Radio Network Planning Tools offer a wide range of
Propagation Models
Propagation Prediction
Information models
Sight Check
Sight Check (Fresnel)
Physical models
Free space
Epstein-Peterson
Empirical models
Okumura-Hata
Mixed models
Longley-Rice
ITU-R P.370
ITU-R P.1546
GEG
L&S VHF/UHF
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Models and Frequency Ranges
1,5GHz
Okumura Hata Model 2
2 GHz
ITU530 Microwave Model
800MHz
70GHz
ITU452 Microwave Model
800MHz
70GHz
800MHz
Walfish Ikegami Model
150MHz
Okumura Hata Model 1
2GHz
1,5GHz
Longley Rice Model
30MHz
Aeronautical Model
30MHz
Flat Earth Model
30MHz
10GHz
Egli Urban Model
30MHz
10GHz
HCM Model
30MHz
ITU370 Model
30MHz
1GHz
ITU 567 Model
30MHz
1 GHz
CEPT Model
30MHz
3MHz
ITU533 Shortwave Model
150kHz
Sky Wave Model
30GHz
2GHz
250 MHz
30MHz
1,7MHz
10 kHz
Ground Wave Model
40GHz
30 MHz
Free Space Model
30 Hz
300 Hz
3KHz
VLF
30KHz
LF
300 KHz
MF
3 MHz
HF
30 MHz
300 MHz
3 GHz
30 GHz
VHF UHF SHF EHF
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300 GHz
Version 15.05.2002 FF
Sight Check
performs line of sight (LOS) check
result
Propagation Prediction
sight
no sight
TX
profile
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Sight Check (Fresnel)
performs extended line of sight (LOS) check
Propagation Prediction
sight, no obstacles within 1st Fresnel zone
result
sight, but obstacle within 1st Fresnel zone
no sight
TX
profile
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Free Space
Propagation Prediction
180
ERP
ERP
ERP
ERP
160
E [dBuV/m]
140
120
=
=
=
=
1W
10 W
100 W
1 kW
100
80
propagation over a flat earth
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40
20
0
0
10
20
30
40
50
60
70
80
90
100
d [km]
Determines the field strength value purely on the basis of the loss due to the
distance d from the transmitter
Selected calculation mode affects the k-factor for the calculation (see sight check)
Additionally the consideration of morphological classes is possible if available; the
clutter heights of the urban and rural morphologic classes are added to the
topological heights
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Propagation Model ITU-R 370
latest version 1995
Propagation Prediction
coordination model ⇒ tends to overestimate fieldstrength
basis:
measured data from North America, Europe, North Sea (cold) and Mediterranean
Sea (warm)
condensed to a set of curves: fieldstrength E over a homogenous terrain as a
function of distance d (10 km ... 1 000 km) for ...
frequency ranges VHF (30 ... 250 MHz) and UHF (450 ... 1 000 MHz)
power of 1kW ERP
effective transmitter antenna height 37.5 m ... 1 200 m (3 km ≤ d ≤ 15 km)
terrain roughness ∆h = 50 m (10 km ≤ d ≤ 50 km)
receiver location over land, cold sea or warm sea
receiver antenna height hR = 10 m
50 % location probability
1%, 5%, 10% and 50% time probability
Used for highest compatibility with international planning procedures
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ITU-R 370 - Definition heff
Propagation Prediction
heff = hsite, asl + hantenna - hav
hav:
average terrain height between 3 km and 15 km from transmitter
Transmitter
heff
0
3 km
15 km
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ITU-R 370 - Definition ∆h
∆h is the difference between terrain heights exceeded by 10% and
90% of the values between 10 km and 50 km from the transmitter
50 km
800
800
700
700
600
600
500
∆h
h [m]
h [m]
10 km
500
300
400
300
200
200
100
100
400
0
0
Propagation Prediction
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34
45
55
67
77
distance from transmitter d [km]
0
90%
10%
1
10 20 29 39 49 58 68 77 87 97
% (10 km ... 50 km)
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ITU-R 370 – Propagation Curves
Propagation Prediction
Free space propagation
heff = 150 m
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Free space propagation
heff = 150 m
propagation curve 50% time
propagation curve 1% time
(steady or continuous)
(tropospheric)
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ITU-R 370 – Implementations
Propagation Prediction
3 different Implementations for ITU-R 370 Models
ITU-R 370 Database
effective antenna height from database
∆h = const. from user
ITU-R 370 Transmitter
effective antenna height from database
∆h dynamically from digital terrain data
ITU-R 370 Terrain
effective antenna from digital terrain data
∆h dynamically from digital terrain data
-> see Live Demo
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The New Model: ITU-R 1546
Propagation Prediction
Major changes between ITU-R 370 and ITU-R 1546
Interpolation and extension in frequency (between 3 curves from 30 MHz ... 3
000 MHz)
Extension to distances below 10 km from transmitter (1 km)
Terrain roughness is no longer a parameter
More complex calculation near the transmitter
calculation procedure for negative heff, curves extended to 10 m
Interpolation for time variability (between curves)
Location's standard deviation as a function of frequency
More complex land sea path calculation
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Okumura-Hata
Propagation Prediction
empirical model for propagation along flat and homogenous urban terrain
based on measurements for vertical polarization by Okumura and ...
interpolated formulas by Hata
Extensions to Okumura-Hata
calculation of effective transmitter antenna height
hT → hT,eff (different options)
additional diffraction term for paths without sight
consideration of morphological heights in diffraction term
subdivision of the 4 morphological classes of Okumura-Hata into 16 classes
(morphological gain with respect to urban areas)
correction for non flat earth (terrain slope)
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Okumura-Hata
Model parameters for Extended Hata Model
Edit
Editcoefficients
coefficientsof
of
hata
equation
hata equation
Set
Setfrequency
frequencyand
and
receiver
heigth
receiver heigth
Enable
Enableearth
earth
curvature
curvature
correction
correction
Enable
Enablediffraction
diffractionmodel
model
-Deygout
(ITU)
-Deygout (ITU)
-Epsteint
-EpsteintPetersen
Petersen
enhanced for speed)
-Deygout
(
-Deygout (enhanced for speed)
Propagation Prediction
Edit
Editparameter
parameter
for
for
tangent
tangentfitting
fitting
Select
Select
environment
environment
correction
correction
Set
Setparameter
parameter
for
morpho
for morpho
model
model
Select
Selectmorpho
morpho
model
model
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Micro Cell Model
Propagation Prediction
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Prediction Models
Propagation Prediction
Non-Terrain Based
• Use of "effective antenna height"
• Monotonous decline of field strength with
increasing distance to transmitter
Example: ITU-R P. 370
DTM Based
• Diffraction, shading, reflection
• Terrain elevation and land use (morphology)
• 2D and 3D models
Examples:
"Epstein-Peterson", "Longley&Rice",
"Okumura-Hata"
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Live
Planning Tool Demonstration
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