Definitions of parameters within different materials used
When I checked the penetration parameters of different materials, I found that there are three parameters:
- Transmission
- Reflection
- Diffraction
The unit of above parameters are dB. But I think that an attenuation parameter should have a unit also including thickness, for example, 6.5dB/meter.
The three loss values: transmission, reflection and diffraction are defined per material type and per thickness of each material type. Furthermore, under the description of each material in the database there is a specified thickness. This essentially means that 0.1m Medium Dry Wall, 0.2m Dry Wall and 0.3m Dry Wall would all by defined as different materials within the tool.
The reason for this is that an increase in material thickness does not result in a directly proportional increase in the loss value for that material and would require a level of interpolation / 'guess work' which could introduce some inherent inaccuracies into the building model.
Thickness is not consider again in the the prediction in our current propagation engine. We already considered this parameter in the Transmission, Reflection and Diffraction Loss.