Clutter Loss Options

Within SignalPro we have several different ways to apply excess clutter pathloss. To include a clutter loss option, you will need to be sure to “switch on” the appropriate option from within the propagation model menu. You can get to the propagation model menu by going to Studies>Propagation models. See dialogue box below:

Each clutter option is different and what you use depends on the system/scenario you are modeling. There are 3 options:

Add Clutter Loss
Add clutter pass-through loss
Add clutter height to terrain height

These three options control how excess pathloss is applied for the clutter. Each option uses different values from the attenuation file.

Please note: If you make changes to the attenuation file for a certain value, for example Loss from clutter at receiver, and your study results are not affected, this could be a result of using a clutter loss that does not correspond to the value that was changed in the attenuation file.

Description of clutter loss options:

The Add Clutter Loss option applies a fixed amount of additional pathloss based on the clutter type at the UE/mobile unit only (this does not look at clutter along the path). The 'Loss from clutter at receiver' table within the attenuation file adjusts the loss taken into account at the mobile unit, but only if the 'Add Clutter Loss' option is checked. This is generally used for situations where the Transmitter sites are elevated above the clutter but the mobile/remote unit is down within the clutter and you expect most clutter-based loss is local to the mobile.

The 'Add clutter pass-through loss' treats the clutter as a lossy screen. It evaluates the clutter heights along the path and applies excess pathloss in dB/Km when the line of sight path is within the height of the clutter. The amount of loss is controlled by the 'Pass-through clutter loss' table in the attenuation file. This is typically used for situations where transmitter tower heights are low and clutter loss is due to obstructions anywhere along the propagation path, instead of just local to the mobile.

The 'Add clutter height to terrain height' option will treat the clutter as a solid obstacle to be diffracted over; excess pathloss is based on the diffraction angle as the path goes over the top of the clutter. The heights of the clutter are set in the attenuation file (assuming that you're not using a .CHT clutter height file instead). This is most often used for back-haul planning or situations where you want to treat clutter as pessimistically as possible. If the mobile unit is below the height of the clutter, this model tends to be very conservative and is not appropriate for most mobile planning.

Clutter loss options displayed in path profiles

Below is what a path will look like with only the Add clutter loss option switched on:

Path profile with Add pass-through clutter loss switched on. As you can see, the clutter heights are taken into effect. However, the path will pass-though the clutter and take the pass-through loss into account as explained above:

This last path profile is Add clutter height to terrain height switched on. The clutter heights are taken into effect. However, the path treats the clutter heights as a knife edge to diffract over, as explained above:

For any additional assistance with the clutter loss options, please submit a support ticket. You can use the following link to create a support ticket: https://edxwireless.atlassian.net/servicedesk/customer/portal/2