Influence of Antenna Performance and Propagation Channel on Pulsed UWB Signals

The main objective of UWB antennas is capability of radiation over very wide bandwidth. But this is not a sufficient condition for proper operation with a pulse based system because different antennas radiate the pulses in different forms. That is why a temporal behavior of an antenna has to be also taken into account during the design. Also during propagation in a real environment the radiated signal will undergo additional distortion due to multi path propagation effects. In this paper firstly the quality measures of an UWB antenna are described followed by the description of main radiation principles supported by examples and measurement results. The focus will be put on relationship between antenna types and applicability to UWB systems. Next possibilities to model an UWB channel are described followed by a discussion of it's influence on UWB system performance.