The road surface monitoring system installed in the infrastructure system is very critical to calculating the braking distance that is needed for keeping a safety distance between cars. To meet this requirement, a 95GHz-band radiometer was fabricated, having innovative features that other sensors do not have, that is, an all-weather performance, night-and-day use, and passive sensor. Using the radiometer, the sky temperature, road surface brightness temperature, and road surface temperature to obtain emissivity values were measured. The graph that indicates the emissivity of the horizontally polarized wave on the horizontal axis and the difference in emissivity between the horizontally and vertically polarized wave on the vertical axis was produced. As a result, five different road surface conditions (dry, wet, water film, snow, and ice) were displayed separately, revealing that it is quite possible to discriminate between these road conditions. (A*)
Abstract