Ultrawideband propagation channels and their impact on system design

The performance of ultrawideband (UWB) communications systems is determined by the propagation channels they operate in. This paper gives an overview of UWB channels and their impact on system design. The emphasis lies on (i) multiple-antenna systems and (ii) body-area networks. We discuss the frequency dependence of angular power spectra and show that spatial multiplexing can be used for achieving very high data rates in MIMO-UWB systems. For body-area networks, we And small delay spreads, so that high-rate communications can be supported with relatively simple receiver structures. Finally, we argue that the clustering structure and "soft onset" property of UWB power delay profiles strongly influence the design of ranging systems.