In order to make correctly calculations using the Longley-Rice propagation, model should take into account a number of input parameters describing the weather phenomena, system parameters, sitting criteria, statistical criteria which was shown in the table below.
Figure 476: GUI of the Longley Rice
Table 91: Longley Rice propagation model
Description | Symbol | Type | Unit | Comments | |
Variation | - | B | - | Variation in path loss takes into account the uncertainty of building design, furniture, room size, etc. | |
Mean surface refractivity (Ground refractivity) | - | S | Ns | Equatorial | 360 |
Terrain irregularity parameter | - | S | M | Flat Hills | 0 90 500 |
Electrical ground Conductivity | - | S | S/m | Average ground | 0.005 0.001 0.020 0.010 |
Relative permittivity | - | S |
| Average ground | 15 |
Polarisation | - | List | - | 0 – horizontal, 1- vartical | |
Sitting Criteria | - | List | - | Random, Careful, Very Careful | |
Radio climate | - | List | - | Equatorial | |
Time percentage | - | D or S | % | 0.01 – 0.99 | |
Location percentage | - | D or S | % | 0.01 – 0.99 | |
Confidential percentage | - | D or S | % | 0.01 – 0.99 | |
Mode of variability | - | List | - | Single, individual, broadcast | |
Standard deviation | Std. dev. | S | dB |
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