Policy on Intellectual Property Right (IPR)
Annex Wide-range propagation model Description of the calculation
method
1
Introduction
1.1
Applicability
1.2
Reciprocity, and the designation of terminals
1.3
Iteration
1.4
Organization of the document
1.5
Style of description
2
Inputs
2.1
Terrain profile
2.2
Other inputs
2.3
Constants
3
Preliminary calculations
3.1
Limited percentage times
3.2
Path length, intermediate points, and fraction over sea
3.3
Antenna altitudes and path inclination
3.4
Climatic parameters
3.4.1
Refractivity in the lowest 1 km
3.4.2
Refractivity in the lowest 65 m
3.4.3
Precipitation parameters
3.5
Effective Earth-radius geometry
3.6
Wavelength
3.7
Path classification and terminal horizon parameters
Case 1. Path is LoS
Case 2. Path is NLoS
Continue for both cases
3.8
Effective heights and path roughness parameter
3.9
Tropospheric-scatter path segments
3.10
Gaseous absorption on surface paths
3.11
Free-space basic transmission loss
3.12
Knife-edge diffraction loss
4
Obtaining predictions for the principal sub-models
4.1
Sub-model 1. Normal propagation close to the surface of the Earth
4.2
Sub-model 2. Anomalous propagation
4.3
Sub-model 3. Troposcatter propagation
4.4
Sub-model 4: Sporadic-E
5
Combining sub-model results
5.1
Combining sub-models 1 and 2
5.2
Combining sub-models 1 + 2, 3 and 4
5.3
Combining sub-models within a Monte-Carlo simulator
Appendix A Diffraction loss
A.1
Introduction
A.2
Spherical-Earth diffraction loss
A.3
First-term spherical-Earth diffraction loss
Start of calculation to be performed twice
A.4
Bullington diffraction loss for actual profile
Case 1. Path is LoS for effective Earth curvature not exceeded for p%
time
Case 2. Path is NLoS for effective Earth curvature not exceeded for p%
time
A.5
Bullington diffraction loss for a notional smooth profile
Case 1. Path is LoS for effective Earth radius exceeded for p% time
Case 2. Path is NLoS for effective Earth radius exceeded for p% time
Appendix B Clear-air enhancements and fading
B.1
Introduction
B.2
Characterize multi-path activity
For LoS path:
For NLoS path:
B.3
Calculation of the notional zero-fade annual percentage time
B.4
Percentage time a given clear-air fade level is exceeded on a surface
path
B.5
Percentage time a given clear-air fade level is exceeded on a
troposcatter path
Appendix C Precipitation fading
C.1
Introduction
C.2
Preliminary calculations
C.3
Percentage time a given precipitation fade level is exceeded
C.4
Melting-layer model
C.5
Path-averaged multiplier
Appendix D Anomalous/layer-reflection model
D.1
Characterize the radio-climatic zones dominating the path
Large bodies of inland water
Large inland lake or wet-land areas
D.2
Point incidence of ducting
D.3
Site-shielding losses with respect to the anomalous propagation
mechanism
D.4
Over-sea surface duct coupling corrections
D.5
Total coupling loss to the anomalous propagation mechanism
D.6
Angular-distance dependent loss
D.7
Distance and time-dependent loss
D.8
Basic transmission loss associated with ducting
Appendix E Troposcatter
E.1 Introduction
E.2
Climatic classification
E.3
Calculation of troposcatter basic transmission loss
Appendix F Attenuation due to gaseous absorption
F.1
Introduction
F.2
Gaseous absorption for surface path
F.3
Gaseous absorption for a troposcatter path
F.4
Gaseous absorption for terminal/common-volume troposcatter path
F.5
Water-vapour density in rain
F.6
Specific sea-level attenuations
Appendix G Sporadic-E propagation
G.1
Derivation of foEs
G.2
1-hop propagation
G.3
2-hop propagation
G.4
Basic transmission loss
Appendix H Great-circle path calculations
H.1
Introduction
H.2
Path length and bearing
H.3
Calculation of intermediate path point
Appendix I Iterative procedure to invert a cumulative distribution
function
I.1
Introduction
I.2
Iteration method
Stage 1: setting the search range
Stage 2: binary search
Appendix J Structure of the wide-range propagation model
J.1
Introduction
J.2
Combining the sub-models