Since the 1970s, efforts have been made to limit emissions from motor vehicles in order to minimize the release of harmful combustion components for both humans and nature. In 1992, a standardized rolling test cycle, the NEDC, was established in the EU as the basis for emissions measurement. However, since the NEDC is a very static rolling test, a more dynamic emissions test, the WLTP, has been introduced in the EU starting in 2017. This consists of a dynamic rolling test, the WLTC, and an RDE test conducted on public roads. To incorporate these measured RDE emissions into a program called PHEM (Passenger car and Heavy duty Emission Model) in the future, this work was created. Initially, a needs assessment for the simulation was conducted, highlighting areas for improvement in measurement and simulation content. Based on the identified improvements, RDE tests were subsequently conducted. These tests can illustrate improvements or deteriorations in certain aspects/areas. Finally, the parameterization of the vehicle models is discussed.