The recent interest in ultra-wideband (UWB) systems requires an accurate modelling of the radio channel characteristics. Among these, the fading properties of the UWB channel are of particular interest in the development of the air interface. This paper reports on an experiment designed to study spatial and temporal fluctuations of the UWB signal conjoindy in the 3.1 to 11 GHz frequency band, in a typical indoor office environment. The proposed analysis of the small-scale amplitude distribution shows significant differences between the two concepts and provides novel results that complement the available studies