Input parameters

Description

Symbol

Type

Unit

Comments

Variation

-

boolean

-

Variation in path loss.

Diffraction only

-

boolean

-

Select to compute only the diffraction component of the propagation model

Water concentration

ρ

S

g/m³

water vapour density (default 3 g/m³)

Surface pressure

P

S

hPa

Surface pressure (default 1013.25 hPa)

Refraction index gradient

ΔN

S

1/km

The average radio-refractive index lapse-rate through the lowest 1 km of the atmosphere, provides the data upon which the appropriate effective Earth radius can be calculated. Note that ΔN is a positive quantity.

Surface temperature

T

S

Degree Celsius

Surface temperature (default 15 degree Celsius)

Latitude

S

Degree

Latitude of the path-centre location between Tx and Rx

Antenna gain at the Tx

G_t

S

dB

Antenna gain of the Tx in the direction of the horizon along the great-circle interference path (dBi)

Antenna gain at the Rx

G_r

S

dB

Antenna gain of the Rx in the direction of the horizon along the great-circle interference path (dBi)

Sea level surface refractivity

N₀

S

-

The sea-level surface refractivity used by the troposcatter model as a measure of location variability of the troposcatter scatter mechanism. The correct values of ΔN and N₀ are given by the path-centre values as derived from the appropriate maps.

Time Percentage

p

D

%

Percentage time variability for which the basic transmission loss is not exceeded.

Local clutter conditions at Tx/Rx

Predefined set of clutter (ground-cover) categories that the user can choose from: Suburban, Dense suburban, Urban, Dense urban, High-rise urban, and Industrial zone.

User specified clutter nominal heights at Tx/Rx

ha_t, ha_r

S

m

Clutter nominal heights specified by user if different from above

User specified clutter nominal distance from Tx/Rx

dk_t, dk_r

S

m

Nominal clutter distances from Tx/Rx antenna, specified by user if different from above