The anticipated convergence of wireless communications and the internet demands for ever increasing data rates on radio air-interfaces for short range indoor as well as medium to wide range outdoor communications systems. This research activitiy aims at the development of key technologies and know how for the design of the radio links of future high-speed mobile systems. The characterization of the mobile radio channel is one of the key requirements for a successful system design. Channel measurement techniques and channel models are investigated in this project. On the transmission side, the focus lies on advanced signaling techniques, considering spread spectrum, OFDM (orthogonal frequency devision multiplexing), and UWB (ultra wideband) radio technologies. Here the primary goal lies in the development of signal processing algorithms that are needed for the robust detection of the wideband data streams in the presence of multipath, noise, multi-user interference, and other disturbances.