Radiometrisk fjärrmätning av isbildning på vägytor

Abstract

This report investigates the ability to determine road conditions with radiometric remote sensors, in order to detect ice or water at a distance. The project consists of the development of a theoretical model, with associated assumptions and delimitations, numerical simulations in COMSOL Multiphysics as well as experimental measurements to verify or dementiate the theoretical model. The concept of detection uses the surface dielectric constant’s dependance of material, which means that radiation from the atmosphere will be polarized differently upon reflection. Experiments were made using artificial road surfaces similar to real road conditions. In order to carry out the experimental measurements, a radiometer was constructed. The conclusion is that the concept has the potential to differentiate between the road surfaces asphalt, water and a thick and smooth layer of ice. Some exact thresholds for polarization difference require further measurements. For layer structures that have a rough uppermost layer the theoretical model of the project has great difficulty to predict the polarization difference, but potentially further development can help model these cases better.