Rural, ITU P.1546

Calculate propagation in a rural scenario for the ITU P.1546 standard.

ITU P.1546 Standard

The ITU P.1546 standard is used for radio broadcasting propagation predictions for terrestrial services in the frequency range, 30 to 3000 MHz. It is intended for the use of tropospheric radio circuits over land, water, or mixed land-water paths up to 1000 km.

Model Type

In this rural/suburban scenario, the geometry is described by topography (elevation) and clutter (land usage such as forest, open area, residential). In the tree view, click Topography to view the topography database or Clutter/Morpho to view the land usage.



Figure 1. Topography for the rural area.

Sites and Antennas

The topography includes two sites with omnidirectional antennas. The first site is denoted “Raichberg Tower” and placed at a height of 1093 m. The second site is denoted “TV Tower Stuttgart” and placed at a height of 685 m (relative to sea level).
Tip: Click Project > Edit Project Parameter and click the Sites tab to view the sites and antennas.
The transmitter power is 1000 W, and the carrier frequency is 225.65 MHz.

Computational Method

The computation uses the ITU P.1546 broadcasting propagation model. The method is based on interpolation/extrapolation from empirically derived field-strength curves as functions of distance, antenna height, frequency, and percentage time. The calculation procedure also includes corrections to account for terrain clearance and terminal clutter obstructions. Location probability refers to the spatial statistics of local ground cover variations. Time variability allows for the validation of the model for a percentage of times within the range of 0 to 50%. Special settings distinguish between urban, non-urban, and sea areas.

In addition, the knife edge diffraction model provides an efficient extension for the coverage prediction beyond the line of sight.

Tip: Click Project > Edit Project Parameter and click the Computation tab to change the model.

Results

Results are computed for each transmitter at a prediction plane of 1.5 m. Propagation results in this project include power coverage of each transmitting antenna (that is the power which a hypothetical isotropic receiving antenna would receive) and the minimum number of interactions for both sites. As an example, the minimum number of interactions to reach any point for the “TV Tower Stuttgart” are as shown in Figure 2.



Figure 2. Minimum number of interactions required to reach any point for the “TV Tower Stuttgart”.