1. ATDI Propagation Models in ICS telecom

2. identify which radio propagation models are implemented in ICS telecom
Webinar aim:
identify which radio propagation models
are implemented in ICS telecom
Including:
Propagation model limitations
Clutter settings
What calculations take place
Identifying the most appropriate model
Examining the useful / popular radio propagation models
nb. Due to time constraints the lesser known radio propagation models including corrections such as rain, gas and reflections will not be covered.

3. ATDI implementation & comments
Webinar aim: present propagation models in a similar form to ITU-R P
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Name of Method in ICS Telecom
Where the application is used eg. Broadcast, areonautical etc
Point- to- point or point to area
Field strength, pathloss
Valid frequency range of operation
Valid distance (s)
% time factored into calculation
% locations factored into calculation
Valid range of terminal heights
Data required to operate the propagation calculation
Comments on implementation in ICS Telecom
A guide to radio propagation models in ICS telecom
will be published shortly.

4. Definitions
Digital Terrain Model (DTM) – bare ground height – man-made modifications tend to be ignored such as cuttings and embankments, etc
Clutter – What is on the bare ground including trees, buildings (suburban, urban)
Absorption
Diffraction
T = transmitter
R = receiver
Power absorbed by obstacle
Diffraction loss

5. How clutter is used Clutter code 9 Used for “building
layers” – not covered
in this presentation
Applies factor to clutter
height ie, if forrest 15m
high diffraction point
= 0.6 x 15 = 9m
Clutter height
Applied at all locations
dB/km applied every time
clutter is in transit
Flat attenuation
Applied only at
Receiver pixel

6. Clutter settings Clutter T/R over ground spot RX Over Clutter
relaxed
Clutter
Over
Ground RX
Ground

7. General Concept Represents pixel of clutter urban
Represents pixel of ground (DTM)

8. Represents pixel of ground (DTM)
Represents pixel of clutter suburban
Represents pixel of clutter urban

9. dB/km Diffraction loss From last diffraction point
Represents pixel on ground (DTM)
Represents pixel of clutter urban
with clutter height x and dB/km y
Absorption loss = 4 x y / DTM raster size
Clutter attenuation = MIN (diffraction loss , absorption loss)
Clutter attenuation = Diffraction loss + Absorption loss

10. Diffraction loss
from last diffraction
point A B
Flat attenuation
Absorption loss = 4 x y / DTM raster size
At Location A (RX height > Clutter height)
Clutter attenuation = MIN(Diffraction loss , Absorption loss)
Clutter attenuation = Diffraction loss + Absorption loss
At Location B (RX height < Clutter height)
Clutter attenuation = MIN(Diffraction loss , Absorption loss) + Flat attenuation
Clutter attenuation = Diffraction loss + Absorption loss + Flat attenuation

11. Flat + absorption Diffraction loss from last diffraction point
10dB
10dB
Represents pixel of ground (DTM)
Represents pixel of clutter urban
with clutter height x and dB/km y
Clutter attenuation = MIN (Diffraction loss , Absorption loss = summation of flat loss for
each separate obstacle)
Clutter attenuation = Diffraction loss + Absorption loss which is summation of flat loss for
Each separate obstacle

12. Clutter height 8m
Clutter height 30m
10dB

13. Flat + diffraction mode
Diffraction loss
Only if RX > clutter height
Flat + diffraction mode
If RX height < Clutter height Clutter loss = diffraction + clutter attenuations
into RX pixel)

14. Clutter when using DSM or DEM
Clutter not used in calculation
Clutter might be used to identify
Roof tops / street levels

15. Other Clutter modes
CCIR and UER are similar to flat + diffraction, except with standard values for mobiles (CCIR) and TV reception (UER)
TSB-88 Mode (NTIA report TSB-88-B similar to flat + diffraction except clutter attenuation need to change with frequency (clutter height should be set to zero)
USER same as flat + diffraction except where RX height > clutter height in which case it is diffraction + flat attenuation into last pixel
Clutter code 9 has a specific role and is used as identification for building layer
Building layers are not covered in this webinar
Demonstrate best way to test clutter settings and attenuations.
DEMO

16. Radio Propagation Models
Main Models
ITU-R 525/526 Deygout
ITU-R 525/526 Bullington
ITU-R
ITU-R
ITU-R 452
Other Useful Models
Okumura/ Hata / Davids
ITU-R 528 (optional add on)
These models will be covered in detail during this webinar.

17. These models will not be covered
Other models
Fresnel method +
Wojnar method
Wein method
ITU-R 370
ITU-R 1225
Medium Frequency
3GPP – LTE Rural
3GPP – LTE urban
SUI method
Hata – Cost 231
Cost 231 Open
Skywave LF & MF
Add-on models
Itm122 - Irregular Terrain Model
ITM_NTIA Longley Rice (ITM)
Ground wave – ITU-R P368-7
RRC04
Skywave ITU-R P.435, ITU-R P.1147
Tropospheric Scatter
These models will not be covered
during the webinar . The applicability
of these models will be covered in the
Guide to Radio Propagation models

18. ICS Telecom / HTZ Warfare Radio Propagation model settings
In concept
Some propagation models do not
split into these 3 conditions easily;
in some cases they do not apply TX
Location
RX Location(s)

19. ATDI implementation & comments
ITU-R 525 / 526 Deygout
Standard model in ICS telecom since version 1
Three worst-case intrusions into the Fresnel zone taken into account
ATDI updated method with Deygout94 diffraction where multiple intrusions are taken into account
The ITU have now updated method
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Rec ITU-R P.525
All services
Point-to- point
Field strength
100 MHz to 100 GHz
Not specified
Not applicable
No Limits specified
Frequency Distance
Implemented
Rec ITU-R P and earlier
30 MHz to 100 GHz
Radio horizon
Not applicable (50% time only)
Path profile data Frequency Distance
Implemented, This model takes into account a maximum of 3 intrusions into the Fresnel zone and is a Dygout model

20. effective Diffraction point
ITU-R 525/ Bullington
526 model uses the following parts of
Spherical earth section 3.2
Bullington model section 4.5
Rounded earth, knife edge,
multiple obstacles , smooth earth
not implemented because it causes
discontinuities as models switch
Bullington model uses single
effective Diffraction point

21. ATDI implementation & comments
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Rec ITU-R P.525
All services
Point-to- point
Field strength
100 MHz to 100 GHz
Not specified
Not applicable
No Limits specified
Frequency Distance
Implemented
Rec ITU-R P and latter
10 MHz to 100 GHz
Radio horizon
Not applicable (50% time only)
Path profile data Frequency Distance
Implemented, This model takes into account the worst intrusions and develops and single representative intrusion and uses Bullington model

22. ATDI implementation & comments
ITU-R 452
Point to Point calculation
Based on ITU-R P. 525 / (Deygout)**
For 50 to 0.001% time
Settings must be correct in ICS telecom
2 clutter variables in the calculation ha and dk.
- ha is set in clutter heights
dk value applied is based on clutter code
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Rec. ITU-R P.452
Services employing stations on the surface of the Earth; interference
Point-to- point
Path loss
100 MHz to 50 GHz
Not specified but up to and beyond the radio horizon
0.001 to 50 Average year and worst month
Not applicable
No limits specified
Path profile data Frequency Percentage time Tx antenna height Rx antenna height Latitude and longitude of Tx Latitude and longitude of Rx Meteorological data
Implemented. Note do NOT tick “Flat earth profile sent to DLL”
** Note this will be changed to Bullington in near future

23. The codes 2,3,4,5,8,10 are fixed for a given clutter
e.g. if you have coniferous trees it must be code 8 , then fill in height = 20m.
Similarly, .dk is derived from a lookup – DON’T enter it.
If clutter code=8 (Coniferous trees), dk=0.05;
If clutter code=5 (Tropical rain forest), dk=0.03;
If clutter code=2, 3 or 4 (Urban), dk=0.02;
If clutter code=10 (Industrial zone), dk=0.05.
For the remaining clutters, fill in the heights and it will use the corresponding value of dk:
If clutter height=4m, dk=0.1;
If clutter height=5m, dk=0.07;
If clutter height=15m, dk=0.05;
If clutter height=9m, dk=0.025;
If clutter height=12m, dk=0.02;
If clutter height=25m, dk=0.02;
ha must be set in the clutter dialogue box

24. ITU-R P.453 (Fig 4-7) or P. 452-14 (Fig 11)
MUST be un-ticked
ITU-R P.453 (Fig 1,2) or (Fig 13)
ITU-R P.453 (Fig 4-7) or P (Fig 11)
Recommended clutter settings based on
Table 4
ATDI recommends that
ATDI standard clutter
designations are used
Note 1: Clutter level 6 must be sea / water
Note 2: Ofcom has modified version of Infotera Clutter to use with P.452 model.

25. ITU-R 1546 Broadcast / International Coordination / Interference
Related to ITU-R 370
Only considers terrain within 15km of transmitter
Uses clutter and takes off angle to modify prediction
Uses propagation curves for different frequencies / % time
Not symmetrical (loss A  B  Loss B  A )
If not standard then ATDI clutter codes
will need to be set up

26. ATDI implementation & comments
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Rec. ITU-R P.1546
Terrestrial services
Point-to-area
Field strength
30 to 3 000 MHz
1 to 1 000 km
1 to 50
1 to 99
Tx/base: effective height from less than 0 m to 3 000 m Rx/mobile: ³ 1 m
Terrain height and ground cover (optional) Path classification Distance Tx antenna height Frequency Percentage time Rx antenna height Terrain clearance angle Percentage locations Refractivity gradient
Implemented. Clutter needs to be loaded and clutter heights and calculation method defined. This has also been extended for GE06 (separate DLL file) use with warm/cold sea definition. Note this model in non- reciprocal

27. ATDI implementation & comments
ITU-R
This is a combination of ITU-R P.452, P525, P and is for point to area calculations
This is the only propagation model that takes clutter into account at both ends of the path
Method
Application
Type
Output
Frequency
Distance
% time
% location
Terminal height
Input data
ATDI implementation & comments
Rec. ITU-R P.1812
Terrestrial services
Point-to-area
Field strength
30 MHz to MHz
Not specified but up to and beyond the radio horizon
1 to 50
1 to 99
No limit
Path profile data Frequency Percentage time Tx antenna height Rx antenna height Latitude and longitude of Tx Latitude and longitude of Rx Meteorological data
Implemented. Clutter heights need to be defined for mid path clutter height, Clutter values used with terminal heights from table 2 as standard for terminal clutter losses

28. ITU-R P.1812-2 Terminal clutter height is related to Clutter code
(ITU-R P Table 2)
ATDI Clutter
code 6 1
2,3,4,5,8 7

29. Okumura Hata
Mobile operators tend to use this model and fine tune it with drive tests
Model is based on clutter not terrain, so is designed for small ranges
The extended Hata model has not been implemented yet. If required please let ATDI know. NB. this model is for SRD with ranges in meters and for indoor and outdoor.
To use this model effectively on a DTM a high resolution map would be required (1 -5 m / pixel)

30. Propagation Regions Line of sight (LOS) Diffraction Tropospheric
Loss
Distance
Note: This propagation model is an add on to ICS Telecom and needs to be
Purchased separately

31. Other Corrections to Propagation Models
Rain - World based on ITU-R P.538 and UK rain on Ofcom data
Snow – Isotherm level (level at which water freezes) if path passes though this level this correction is applied
Fog – ITU-R 840
Gas – ITU-R 676 (Note ITU-R F.1820 is Gas attenuation from HAP at 47GHz)
Wave height - (applies an effective clutter height depending on wind strength)
Reflections

32. Comparison of Radio Propagation models in ICS telecom
DEMO

33. Thank you for attending today Any questions
Thank you for attending today Any questions? ATDI Limited The Beehive – City Place – Gatwick West Sussex – RH6 0PA – UK Tel +44 (0) Fax +44 (0)