Rural, Ray Tracing

Calculate propagation in a rural scenario using rural ray tracing (RRT).

Benefits of Rural Ray Tracing Over 3D Ray Tracing

This example uses the RRT, which is a deterministic multi-path propagation method. This method considers phenomena, such as multiple reflections and diffractions. For each receiver pixel, the rays always travel in the 2D vertical plane between transmitter and receiver. This makes the method faster than full 3D ray tracing.

Model Type

The geometry is described by topography (elevation), see Figure 1. The RRT requires the conversion of the topography data from pixel format (points specifying elevation) into a 3D vector data format (triangles describing the terrain). This step can be done using the conversion functions available in WallMan (File > Convert Topo Database). In this process, you specify the .tdb file which is the file with pixel description of the terrain, as well as the name of the .tdv file (vector description destination file) and other info when prompted. You can also add buildings (additional vector objects).

After completing the conversion process, the rural vector database is written to this .tdv file.

Figure 1. Topography for the rural area.

Sites and Antennas

The model contains a single site with one omnidirectional antenna. The antenna is placed at a height of 45 m and operates at 450 MHz. The transmitter power is 40 dBm. The site and antenna are placed outside the prediction area (displayed in red). The prediction area contains a few buildings (additional vector objects) for which the received power and shadowing are of interest.

Computational Method

The RRT is selected by clicking Project > Edit Project Parameter and clicking the Computation tab.


Propagation results show at every location the received power by a hypothetical isotropic receiving antenna. Figure 2 shows the power results. Due to edge diffraction, the shadowing behind the buildings is limited.

Figure 2. Power results of Site 1, Antenna 1.