Ultra-wideband signals have a variety of applications. An upcoming medical application is the detection of the heart rateofpatients. However, current UWB systems provide poor resolution and are only able to detect vessels with a large diameter, e.g. the aorta. The detection and quantification of vascular dilation of thinner vessels is essential to develop wearable ultra-wideband based devices for real-time detection of cardiovascular conditions of the extremities. The reflection and transmission processesofthose signals within inhomogeneous bodies are complex and their prediction is challenging. Inthis paper, wepresent an experimental setup (UWB system; phantom) for the detection of vascular dilation within soft tissues. Furthermore, we suggest a theoretical simulation model for the prediction of the reflection of ultra-wideband pulses and compare these simulated predictions to results of measurements within the phantom. The results verify that we are able to identify vascular dilation within the simulation model and the experimental setup, depending on the depth of the vessel (20 mm, 40 mm, 60mm).